WorldWideScience

Sample records for based district heating

  1. Model-based control of district heating supply temperature

    Energy Technology Data Exchange (ETDEWEB)

    Saarinen, Linn

    2010-11-15

    A model-based control strategy for the supply temperature to a district heating network was tested during three weeks at Idbaecken's CHP plant. The aim was to increase the electricity efficiency by a lower supply temperature, without risking the delivery reliability of heat to the district heating customers. Simulations and tests showed that at high loads, the mean supply temperature could be reduced by 4 deg C and the electricity production could be increased by 2.5%

  2. Upscaling a district heating system based on biogas cogeneration and heat pumps

    NARCIS (Netherlands)

    van Leeuwen, Richard Pieter; Fink, J.; Smit, Gerardus Johannes Maria; de Wit, Jan B.

    2015-01-01

    The energy supply of the Meppel district Nieuwveense landen is based on biogas cogeneration, district heating, and ground source heat pumps. A centrally located combined heat and power engine (CHP) converts biogas from the municipal wastewater treatment facility into electricity for heat pumps and

  3. Upscaling a district heating system based on biogas cogeneration and heat pumps

    NARCIS (Netherlands)

    Leeuwen, van Richard P.; Fink, Jiří; Wit, de Jan B.; Smit, Gerard J.M.

    2015-01-01

    The energy supply of the Meppel district Nieuwveense landen is based on biogas cogeneration, district heating, and ground source heat pumps. A centrally located combined heat and power engine (CHP) converts biogas from the municipal wastewater treatment facility into electricity for heat pumps and h

  4. Upscaling a district heating system based on biogas cogeneration and heat pumps

    NARCIS (Netherlands)

    van Leeuwen, Richard Pieter; Fink, J.; Smit, Gerardus Johannes Maria; de Wit, Jan B.

    2015-01-01

    The energy supply of the Meppel district Nieuwveense landen is based on biogas cogeneration, district heating, and ground source heat pumps. A centrally located combined heat and power engine (CHP) converts biogas from the municipal wastewater treatment facility into electricity for heat pumps and h

  5. GIS based analysis of future district heating potential in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    2013-01-01

    The physical placement of buildings is important when determining the potential for DH (district heating). Good locations for DH are mainly determined by having both a large heat demand within a certain area and having access to local heat resources. In recent years, the locations of buildings...... in Denmark have been mapped in a heat atlas which includes all buildings and their heat demands. This article focuses on developing a method for assessing the costs associated with supplying these buildings with DH. The analysis is based on the existing DH areas in Denmark. By finding the heat production...

  6. Geothermal district heating systems

    Science.gov (United States)

    Budney, G. S.; Childs, F.

    1982-06-01

    Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

  7. Life cycle assessment of base-load heat sources for district heating system options

    Energy Technology Data Exchange (ETDEWEB)

    Ghafghazi, Saeed [University of British Columbia, Vancouver; Sowlati, T. [University of British Columbia, Vancouver; Sokhansanj, Shahabaddine [ORNL; Melin, Staffan [Delta Research Corporation

    2011-03-01

    Purpose There has been an increased interest in utilizing renewable energy sources in district heating systems. District heating systems are centralized systems that provide heat for residential and commercial buildings in a community. While various renewable and conventional energy sources can be used in such systems, many stakeholders are interested in choosing the feasible option with the least environmental impacts. This paper evaluates and compares environmental burdens of alternative energy source options for the base load of a district heating center in Vancouver, British Columbia (BC) using the life cycle assessment method. The considered energy sources include natural gas, wood pellet, sewer heat, and ground heat. Methods The life cycle stages considered in the LCA model cover all stages from fuel production, fuel transmission/transportation, construction, operation, and finally demolition of the district heating system. The impact categories were analyzed based on the IMPACT 2002+ method. Results and discussion On a life-cycle basis, the global warming effect of renewable energy options were at least 200 kgeqCO2 less than that of the natural gas option per MWh of heat produced by the base load system. It was concluded that less than 25% of the upstream global warming impact associated with the wood pellet energy source option was due to transportation activities and about 50% of that was resulted from wood pellet production processes. In comparison with other energy options, the wood pellets option has higher impacts on respiratory of inorganics, terrestrial ecotoxicity, acidification, and nutrification categories. Among renewable options, the global warming impact of heat pump options in the studied case in Vancouver, BC, were lower than the wood pellet option due to BC's low carbon electricity generation profile. Ozone layer depletion and mineral extraction were the highest for the heat pump options due to extensive construction required for these

  8. GIS Based Analysis of future district heating potential in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    2012-01-01

    The physical placement of buildings is important when determining the future potential for district heating (DH). Good locations for DH are mainly determined by having a large heat demand within a certain area combined with an access to local resources. In Denmark, the placement of buildings...... and their heat demand has in recent years been assessed in a heat atlas including all buildings in Denmark. The focus in this article is to further develop a method for assessing the costs associated with supplying these buildings with DH. The analysis takes departure in the existing DH areas in Denmark....... By finding the heat production cost within these areas, and adding transmission and distribution costs, the economic feasibility of supplying areas with DH is found. The result of the analysis is that the DH potential differs from area to area. In many areas it is economically feasible to expand DH, while...

  9. Comparison of district heating expansion potential based on consumer-economy or socio-economy

    DEFF Research Database (Denmark)

    Grundahl, Lars; Nielsen, Steffen; Lund, Henrik

    2016-01-01

    Recent studies show that a high share of district heating is an important part of a future sustainable energy system or smart energy system with a high renewable energy penetration. These studies also show socio-economic benefits of expanding the district heating coverage. However, in order...... to implement such an expansion, district heating needs to be economically feasible for the heat consumers. This aspect is often not investigated and hence it is unknown if calculations based on consumer-economy, where tax payment is included, will yield the same potential of expansion. This study identifies...... the differences in the expansion potential of district heating calculated with a socio-economic and a consumer-economic approach, respectively, in a case study of Denmark. By also investigating the consumer-economy of expanding district heating, a deeper insight is obtained of possible locations for expanding...

  10. Comparison of district heating expansion potential based on consumer-economy or socio-economy

    DEFF Research Database (Denmark)

    Grundahl, Lars; Nielsen, Steffen; Lund, Henrik;

    2016-01-01

    Recent studies show that a high share of district heating is an important part of a future sustainable energy system or smart energy system with a high renewable energy penetration. These studies also show socio-economic benefits of expanding the district heating coverage. However, in order...... to implement such an expansion, district heating needs to be economically feasible for the heat consumers. This aspect is often not investigated and hence it is unknown if calculations based on consumer-economy, where tax payment is included, will yield the same potential of expansion. This study identifies...

  11. Groundwater and geothermal: urban district heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Mounts, R.; Frazier, A.; Wood, E.; Pyles, O.

    1982-01-01

    This report describes how several cities use groundwater and geothermal energy in district heating systems. It begins with groundwater, introducing the basic technology and techniques of development, and describing two case studies of cities with groundwater-based district heating systems. The second half of the report consists of three case studies of cities with district heating systems using higher temperature geothermal resources.

  12. Boise geothermal district heating system

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, P.J.

    1985-10-01

    This document describes the Boise geothermal district heating project from preliminary feasibility studies completed in 1979 to a fully operational system by 1983. The report includes information about the two local governments that participated in the project - the City of Boise, Idaho and the Boise Warm Springs Water District. It also discusses the federal funding sources; the financial studies; the feasibility studies conducted; the general system planning and design; design of detailed system components; the legal issues involved in production; geological analysis of the resource area; distribution and disposal; the program to market system services; and the methods of retrofitting buildings to use geothermal hot water for space heating. Technically this report describes the Boise City district heating system based on 170/sup 0/F water, a 4000 gpm production system, a 41,000 foot pipeline system, and system economies. Comparable data are also provided for the Boise Warm Springs Water District. 62 figs., 31 tabs.

  13. District heating and gas engine heat pump: Economic analysis based on a case study

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Noro, M. [Department of Management and Engineering, University of Padova, Stradella, S. Nicola, 3, 36100 Vicenza (Italy)

    2006-02-01

    'S. Nicola' HVAC plant in Vicenza features innovative and significant energy savings characteristics. It has been set up by a gas engine heat pump (coupled to two condensing boilers) whose performances are here evaluated during three years of operation. Due to a grid expansion, the University received the offer of being connected to the district heating grid. This possibility that is often considered advantageous was economically evaluated. As a result of this, a significant increasing of the building annual energy bill was demonstrated in case of acceptance. (author)

  14. Remote Sensing-Based Characterization of Settlement Structures for Assessing Local Potential of District Heat

    Directory of Open Access Journals (Sweden)

    Michael Nast

    2011-07-01

    Full Text Available In Europe, heating of houses and commercial areas is one of the major contributors to greenhouse gas emissions. When considering the drastic impact of an increasing emission of greenhouse gases as well as the finiteness of fossil resources, the usage of efficient and renewable energy generation technologies has to be increased. In this context, small-scale heating networks are an important technical component, which enable the efficient and sustainable usage of various heat generation technologies. This paper investigates how the potential of district heating for different settlement structures can be assessed. In particular, we analyze in which way remote sensing and GIS data can assist the planning of optimized heat allocation systems. In order to identify the best suited locations, a spatial model is defined to assess the potential for small district heating networks. Within the spatial model, the local heat demand and the economic costs of the necessary heat allocation infrastructure are compared. Therefore, a first and major step is the detailed characterization of the settlement structure by means of remote sensing data. The method is developed on the basis of a test area in the town of Oberhaching in the South of Germany. The results are validated through detailed in situ data sets and demonstrate that the model facilitates both the calculation of the required input parameters and an accurate assessment of the district heating potential. The described method can be transferred to other investigation areas with a larger spatial extent. The study underlines the range of applications for remote sensing-based analyses with respect to energy-related planning issues.

  15. Determining the Optimal Capacities of Renewable-Energy-Based Energy Conversion Systems for Meeting the Demands of Low-Energy District Heating, Electricity, and District Cooling

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend; Dincer, Ibrahim

    2015-01-01

    This chapter presents a method for determining the optimal capacity of a renewable-energy-based energy conversion system for meeting the energy requirements of a given district as considered on a monthly basis, with use of a low-energy district heating system operating at a low temperature, as lo...

  16. Rehabilitation of district heating networks

    Energy Technology Data Exchange (ETDEWEB)

    Ottosson, Peter [AaF-Energikonsult Syd AB (Sweden)

    1996-11-01

    Often the choice is between reparation or exchange of a damaged section of the network. If the exchange is based on the wrong assumptions, large sections of undamaged pipelines could be removed. Most important for the district heating company is to decide which strategy to use for the future exchange of the pipelines. Whichever strategy used, it has to based on an assessment of the network and/or assumptions based on that assessment. The question if it is possible extend the life span of the pipelines arises. What is the most economical choice, the exchange or the renovation. (au)

  17. Solar heat storages in district heating networks

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K. (Ellehauge og Kildemoes, AArhus (DK)); Engberg Pedersen, T. (COWI A/S, Kgs. Lyngby (DK))

    2007-07-15

    This report gives information on the work carried out and the results obtained in Denmark on storages for large solar heating plants in district heating networks. Especially in Denmark the share of district heating has increased to a large percentage. In 1981 around 33% of all dwellings in DK were connected to a district heating network, while the percentage in 2006 was about 60% (in total 1.5 mio. dwellings). In the report storage types for short term storage and long term storages are described. Short term storages are done as steel tanks and is well established technology widely used in district heating networks. Long term storages are experimental and used in connection with solar heating. A number of solar heating plants have been established with either short term or long term storages showing economy competitive with normal energy sources. Since, in the majority of the Danish district heating networks the heat is produced in co-generation plants, i.e. plants producing both electricity and heat for the network, special attention has been put on the use of solar energy in combination with co-generation. Part of this report describes that in the liberalized electricity market central solar heating plants can also be advantageous in combination with co-generation plants. (au)

  18. Future Services for District Heating Solutions in Residential Districts

    Directory of Open Access Journals (Sweden)

    Hannele Ahvenniemi

    2014-06-01

    Full Text Available The underlying assumption of this study is that in order to retain the competitiveness while reaching for the EU targets regarding low-energy construction, district heating companies need to develop new business and service models. How district heating companies could broaden their perspective and switch to a more service-oriented way of thinking is a key interest of our research. The used methods in our study are house builder interviews and a questionnaire. With the help of these methods we discussed the potential interest in heating related services acquiring a comprehensive understanding of the customer needs. The results indicate the importance of certain criteria when choosing the heating system in households: easiness, comfort and affordability seem to dominate the house builders’ preferences. Also environmental awareness seems to be for many an important factor when making a decision about the heating of the house. Altogether, based on the results of this study, we suggest that the prospects of district heating could benefit from highlighting certain aspects and strengths in the future. District heating companies need to increase flexibility, readiness to adopt new services, to invest in new marketing strategies and improving the communication skills.

  19. Wind Energy Integration through District Heating. A Wind Resource Based Approach

    Directory of Open Access Journals (Sweden)

    George Xydis

    2015-03-01

    Full Text Available The aim of this paper is to examine if the surplus of wind energy could be added to electricity-to-heat conversion systems when there is increased congestion in the grid or when there is wind power curtailment. In this way, the produced power can be utilized for contributing to the local district heating (DH system needs. After examining scenarios, optimized energy distribution is recommended. A case study near Kozani, Greece with an onshore wind farm (WF to be installed was thoroughly investigated exploring the options for increased wind energy integration analyzing thermal utilization possibilities based on the local DH needs. A wind resource assessment for the area was done, which optimizes the WF planning and links the DH system with the operation of the WF. The utilization rate between the electric and the DH grid was examined in order to describe the optimal way of the energy to be distributed reassuring profitability for the power producer and robust energy management for the system. It was found that the curtailed wind energy can be locally utilized in a DH system, by covering part of the demand that the diesel-based peak load boiler system does currently.

  20. Integration of Space Heating and Hot Water Supply in Low Temperature District Heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2014-01-01

    District heating makes it possible to provide heat for many consumers in an efficient manner. In particular, district heating based on combined heat and power production is highly efficient. One disadvantage of district heating is that there is a significant heat loss from the pipes to the surrou......District heating makes it possible to provide heat for many consumers in an efficient manner. In particular, district heating based on combined heat and power production is highly efficient. One disadvantage of district heating is that there is a significant heat loss from the pipes...... to the surrounding ground. In larger networks involving both transmission and distribution systems, the heat loss is most significant from the distribution network. An estimate is that about 80-90 % of the heat loss occurs in the distribution system. In addition, the heat loss is naturally highest from the forward...

  1. Heat pumps in district heating networks

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    constraints limit the power plants. Efficient heat pumps can be used to decouple the constraints of electricity and heat production, while maintaining the high energy efficiency needed to match the politically agreed carbon emission goals. The requirements in terms of COP, location, capacity and economy...... are calculated using an energy system model which includes power plants, heat pumps and district heating consumption profiles. The model is developed with focus on accurate representation of the performance of the units in different locations and operating modes. The model can assist in investment decisions...... and strategic planning in the energy sector. The paper presents a case study of optimal implementation of heat pumps in the present energy system of the Copenhagen area. By introduction of the correct capacity of heat pumps, a 1,6 % reduction in fuel consumption for electricity and heat production can...

  2. Nuclear power pilot plant for district heating on tne base of the ARBUS reactor

    Energy Technology Data Exchange (ETDEWEB)

    Tsykanov, V.A.; Chechetkin, Yu.V.; Kormushkin, Yu.P.; Polivanov, I.F.; Pochechura, V.P.; Yakshin, E.K.; Makin, R.S.; Rozhdestvenskaya, L.N.; Buntushkin, V.P.

    1981-06-01

    Problems and perspectives of using reactors with organic coolant for district heating are discussed. Data obtained during plant operation on the base of ARBUS reactor, in which ditolylmethane is used as a coolant, are presented. The principal flow sheet and main parameters of the plant and characteristics of the reactor during operation at different levels thermal power are given. It is concluded that the plant, with the ARBUS reactor is simple and convenient in operation, it permits to quickly increase and decrease loadings and does not require numerous personnel. Standard equipment and accessories used in oil-chemical industry can be the basis for development of plant equipment. Low vapour pressure of the coolant and its weak corrosion activity permit to successfully apply thin-wall tubes and equipment made of carbon steels for the primary circuit. Level of radiation fields from the equipment is not essential during operation and shut-down of the plant and it does not create additional difficulties in operation and maintenance.

  3. Influencing Swedish homeowners to adopt district heating system

    Energy Technology Data Exchange (ETDEWEB)

    Mahapatra, Krushna; Gustavsson, Leif [Ecotechnology, Mid Sweden University, Akademigatan 1, 831 25 Oestersund (Sweden)

    2009-02-15

    Improved energy efficiency and greenhouse gas mitigation could be achieved by replacing resistance heaters with district heating system. In 2005, only about 8% of the Swedish detached houses had district heating system. The expansion of such systems largely depends on homeowners' adoption decisions. And, to motivate homeowners to adopt district heating, it is essential to understand their decision-making process. In this context, in June 2005 we carried out a questionnaire survey of about 700 homeowners who lived in the city of Oestersund in houses with resistance heaters (baseline survey). About 84% of the respondents did not intend to install a new heating system. Since then these homeowners were influenced by (a) an investment subsidy by the Swedish government to replace resistance heaters with district heating, a brine/water-based heat pump, or a biomass-based heating system and (b) a marketing campaign by the municipality-owned district heating company. This paper analyses how these two measures influenced about 78% of the homeowners to adopt the district heating system. For this purpose we carried out a follow-up survey of the same homeowners in December 2006 (resurvey). Results showed that the investment subsidy and the marketing campaign created a need among the homeowners to adopt a new heating system. The marketing campaign was successful in motivating them to adopt the district heating system. The marketing strategy by the district heating company corresponds to the results obtained in the baseline survey. (author)

  4. Alternative solutions for inhibiting Legionella in domestic hot water systems based on low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2015-01-01

    Abstract District heating is a cost-effective way of providing heat to high heat density areas. Low-temperature district heating (LTDH) is a promising way to make district heating more energy-efficient and adaptable to well-insulated buildings with low heating demand in the future. However, one....... The alternative design approach can eliminate the risk factors of Legionella by local temperature boosting and restricting system volume. Decentralized substations, micro heat pumps, electric heating elements and electric heat tracing are all investigated as alternative designs. With regard to sterilization...... systems. They have the additional benefit of reducing the heat loss of the hot water system. The alternative design solutions both enrich our options for water sanitation and improve the energy efficiency of our energy systems....

  5. Local business models for district heat production; Kaukolaemmoen paikalliset liiketoimintamallit

    Energy Technology Data Exchange (ETDEWEB)

    Hakala, L.; Pesola, A.; Vanhanen, J.

    2012-12-15

    Local district heating business, outside large urban centers, is a profitable business in Finland, which can be practiced with several different business models. In addition to the traditional, local district heating business, local district heat production can be also based on franchising business model, on integrated service model or on different types of cooperation models, either between a local district heat producer and industrial site providing surplus heat or between a local district heat producer and a larger district heating company. Locally available wood energy is currently utilized effectively in the traditional district heating business model, in which a local entrepreneur produces heat to consumers in the local area. The franchising model is a more advanced version of the traditional district heating entrepreneurship. In this model, franchisor funds part of the investments, as well as offers centralized maintenance and fuel supply, for example. In the integrated service model, the local district heat producer offers also energy efficiency services and other value-added services, which are based on either the local district heat suppliers or his partner's expertise. In the cooperation model with industrial site, the local district heating business is based on the utilization of the surplus heat from the industrial site. In some cases, profitable operating model approach may be a district heating company outsourcing operations of one or more heating plants to a local entrepreneur. It can be concluded that all business models for district heat production (traditional district heat business model, franchising, integrated service model, cooperative model) discussed in this report can be profitable in Finnish conditions, as well for the local heat producer as for the municipality - and, above all, they produce cost-competitive heat for the end-user. All the models were seen as viable and interesting and having possibilities for expansion Finland

  6. Performance analysis of hybrid district heating system

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Khavin, Gennadii

    2013-01-01

    as problems related to transportation, storage and environmental impacts of biomass and waste utilisation. Implementation of heat storages in district heating systems could contribute to integration of intermittent energy sources. Hybridisation of heat production facility combines two or more different energy...... that combines different energy sources for heat production will be used. The work has been carried out in scope of 4th Generation District Heating Technologies and Systems project.......District heating system could contribute to more efficient heat generation through cogeneration power plants or waste heat utilization facilities and to increase of renewable energy sources share in total energy consumption. In the most developed EU countries, renewable energy sources have been...

  7. Energy savings based on solar heating and improved cooling of the district heating water; Energibesparelser baseret paa solvarme og bedre afkoeling af fjernvarmevandet. Projektrapport

    Energy Technology Data Exchange (ETDEWEB)

    Fafner, K.; Kristjansson, H.; Hansen, Karl Erik

    2009-08-15

    The report analyses and compares the potential for savings in the heat supply, namely use of solar heating and better cooling of the circulating water in the district heating system. The analyses shows that better cooling in the users' heating systems, i.e. lower district heating temperature, should have higher priority than installation of a solar heating system. The report also demonstrates that solar heating continues to have a large un-utilized potential in the Danish heat supply in general, but for the individual building owner installation of a solar heating system will be far more expensive than buying a part of a large-scale solar heating system. However, lowering the return temperature in the district heating transmission pipes is economically more attractive for the building owners than solar heating.

  8. District Heating System Using Heat Pump Installations and CHP

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2015-12-01

    Full Text Available The article describes the district heating system, in which part of the heat of return water thermal power is used to supply heat to the district heating puThe article describes the district heating system, in which part of the heat of return water thermal power is used to supply heat to the district heating pumps, evaporators heating and hot water. Heat pumps use carbon dioxide as refrigerant. During the transitional period of the year, and the summer heat pump for preparing hot-water supply system uses the heat of the surrounding air. The heat of the ambient air is used in the intermediate heat exchanger between the first and second stages of the heat pump to cool the gas after the first stage of the compressor of the heat pump.

  9. The role of district heating in future renewable energy systems

    DEFF Research Database (Denmark)

    Lund, Henrik; Möller, Bernd; Mathiesen, Brian Vad

    2010-01-01

    heating options, including district heating as well as individual heat pumps and micro CHPs (Combined Heat and Power). The study includes almost 25 per cent of the Danish building stock, namely those buildings which have individual gas or oil boilers today and could be substituted by district heating...... or a more efficient individual heat source. In such overall perspective, the best solution will be to combine a gradual expansion of district heating with individual heat pumps in the remaining houses. Such conclusion is valid in the present systems, which are mainly based on fossil fuels, as well......Based on the case of Denmark, this paper analyses the role of district heating in future Renewable Energy Systems. At present, the share of renewable energy is coming close to 20 per cent. From such point of departure, the paper defines a scenario framework in which the Danish system is converted...

  10. Design and System Analysis of Quad-Generation Plant Based on Biomass Gasification Integrated with District Heating

    DEFF Research Database (Denmark)

    Rudra, Souman

    . Different biomass resources are used to generate heat and electricity, to produce gas fuel like bio-SNG (synthesis natural gas) and also to produce liquid fuels, such as ethanol, and biodiesel. Due to the fact that the trend of establishing new and modern plants for handling and processing biomass......This thesis presents the development of energy system for simulation, techno-economic optimization and design of a quad-generation energy system based on biomass gasification. An efficient way of reducing CO2 emission from the environment is by increasing the use of biomass in the energy sector......, it possible to lay a foundation for future gasification based power sector to produce flexible output such as electricity, heat, chemicals or bio-fuels by improving energy system of existing DHP(district heating plant) integrating gasification technology. The present study investigate energy system...

  11. 4th Generation District Heating (4GDH)

    DEFF Research Database (Denmark)

    Lund, Henrik; Werner, Sven; Wiltshire, Robin

    2014-01-01

    This paper defines the concept of 4th Generation District Heating (4GDH) including the relations to District Cooling and the concepts of smart energy and smart thermal grids. The motive is to identify the future challenges of reaching a future renewable non-fossil heat supply as part...... of the implementation of overall sustainable energy systems. The basic assumption is that district heating and cooling has an important role to play in future sustainable energy systems – including 100 percent renewable energy systems – but the present generation of district heating and cooling technologies will have...

  12. Industrial excess heat for district heating in Denmark

    DEFF Research Database (Denmark)

    Bühler, Fabian; Petrovic, Stefan; Karlsson, Kenneth Bernard

    2017-01-01

    the potential for using them for district heating. In this way the theoretical potential of using the excess heat for covering the heating demand of buildings is determined. Through the use of industry specific temperature profiles the heat usable directly or via heat pumps is further found. A sensitivity...... analysis investigates the impact of future energy efficiency measures in the industry, buildings and the district heating grid on the national potential. The results show that for the case study of Denmark, 1.36 TWh of district heat could be provided annually with industrial excess heat from thermal...

  13. Corrosion Rate Monitoring in District Heating Systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Nielsen, Lars Vendelbo; Andersen, A.

    2005-01-01

    Quality control in district heating systems to keep uniform corrosion rates low and localized corrosion minimal is based on water quality control. Side-stream units equipped with carbon steel probes for online monitoring were mounted in district heating plants to investigate which techniques would...... be applicable, and if on-line monitoring could improve the quality control. Water quality monitoring was applied as well as corrosion rate monitoring with linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), electrical resistance (ER) technique, mass loss and a crevice corrosion...... cell for localized corrosion risk estimation. Important variations in corrosion rate due to changes in make-up water quality were detected with the continuous monitoring provided by ER and crevice cell, while LPR gave unreliable corrosion rates. The acquisition time of two-three days for EIS...

  14. Corrosion Rate Monitoring in District Heating Systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Nielsen, Lars Vendelbo; Andersen, A.

    2005-01-01

    Quality control in district heating systems to keep uniform corrosion rates low and localized corrosion minimal is based on water quality control. Side-stream units equipped with carbon steel probes for online monitoring were mounted in district heating plants to investigate which techniques would...... be applicable, and if on-line monitoring could improve the quality control. Water quality monitoring was applied as well as corrosion rate monitoring with linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), electrical resistance (ER) technique, mass loss and a crevice corrosion...... cell for localized corrosion risk estimation. Important variations in corrosion rate due to changes in make-up water quality were detected with the continuous monitoring provided by ER and crevice cell, while LPR gave unreliable corrosion rates. The acquisition time of two-three days for EIS...

  15. Performance Analysis of a Hybrid District Heating System

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Duic, Neven

    2015-01-01

    Hybridisation of district heating systems can contribute to more efficient heat generation through cogeneration power plants or through the share increase of renewable energy sources in total energy consumption while reducing negative aspects of particular energy source utilisation. In this work......, the performance of a hybrid district energy system for a small town in Croatia has been analysed. Mathematical model for process analysis and optimisation algorithm for optimal system configuration has been developed and described. The main goal of the system optimisation is to reduce heat production costs....... Several energy sources for heat production have been considered in 8 different simulation cases. Simulation results show that the heat production costs could be reduced with introduction of different energy systems into an existing district heating system. Renewable energy based district heating systems...

  16. Optimal usage of low temperature heat sources to supply district heating by heat pumps

    DEFF Research Database (Denmark)

    Pieper, Henrik; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    This paper presents a theoretical study on the optimal usage of different low temperature heat sources to supply district heating by heat pumps. The study is based on data for the Copenhagen region. The heat sources were prioritized based on the coefficient of performance calculated for each hour....... Groundwater, seawater and air heat sources were compared with each other as well as to a scenario consisting of a combination of these heat sources. In addition, base load and peak load units were included. Characteristic parameters were the coefficient of performance, the number of full load hours...

  17. District heating substations - design and installation

    Energy Technology Data Exchange (ETDEWEB)

    2004-12-15

    These technical regulations for district heating substations are sector-wide regulations for the Swedish district heating sector, describing the design, installation, use and maintenance of substations. If a district heating substation is to operate in the best possible way, the building's space heating and domestic hot water systems must comply with the requirements in these regulations and with those issued by public authorities. These regulations also describe aspects that must be considered when substations need to be replaced. The use then of correct values for the building energy requirements ensures that the new substation will be properly matched to its duties. These regulations are intended for use by: - those responsible for contacts between the district heating supplier and the customer. - those who own, operate and/or administer a building or facility that is heated by district heating. - those who design, manufacture, purchase, test or install substations. It is recommended that enquiries should refer to the Swedish District Heating Association's technical regulations when specifying requirements. The procurement criteria described in these regulations should be applied when evaluating tenders

  18. Toward 4th generation district heating

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend; Dalla Rosa, Alessandro

    2014-01-01

    In many countries, district heating (DH) has a key role in the national strategic energy planning. However, tighter legislation on new and future buildings requires much less heating demand which subsequently causes relative high network heat loss. This will make current DH system uneconomical co...

  19. Optimising corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.; Andersen, A.

    2002-01-01

    A three-year project - financially supported by the Nordic Industrial Fund - on monitoring of corrosion in district heating systems has been initiated with participation of researchers and industrial partners in Denmark, Finland, Iceland, Norway and Sweden. The primary objective of the project...... is to improve the quality control in district heating systems by corrosion monitoring. In Danish systems electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR), high-sensitive electrical resistance (ER) technology, crevice corrosion probes, as well as weight loss coupons...

  20. Performance analysis of hybrid district heating system

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Khavin, Gennadii

    2013-01-01

    as problems related to transportation, storage and environmental impacts of biomass and waste utilisation. Implementation of heat storages in district heating systems could contribute to integration of intermittent energy sources. Hybridisation of heat production facility combines two or more different energy...... more extensively used in district heating systems either separately or as a supplement to traditional fossil fuels in order to achieve national energy policy objectives. However, they are still facing problems such as high intermittences, high energy production costs and low load factors as well...

  1. District heating and cooling : review of technology and potential enhancements

    Energy Technology Data Exchange (ETDEWEB)

    Rezaie, B.; Rosen, M.A. [Univ. of Ontario Inst. of Technology, Oshawa, ON (Canada). Faculty of Engineering and Applied Science

    2010-07-01

    This study reviewed the economic and environmental aspects of district energy systems in order to facilitate research into expanded thermal networks. The work is part of a broader research program by the authors regarding the use of integrated thermal networks, based on expanded district heating and cooling systems, to meet the thermal requirements for various buildings and applications with greater efficiency and less environmental impact than traditional systems. This paper presented various definitions, classifications and applications of district cooling and heating and described the elements of a district energy system. The study investigated the integration of combined heat and power (CHP) with district energy, permitting the cogeneration of electricity and heat. Environmental benefits are among the main advantages of district heating and cooling systems. This paper described the economics of a thermal network system, as a major factor in the justification for any project from industrial, governmental and societal perspectives. Related regulations at government levels were also suggested based on various investigations. The efficiency of district energy was discussed and exergy analysis was shown to be an effective method for calculating the efficiency of a thermal network. 38 refs., 2 tabs., 2 figs.

  2. Renewable-based low-temperature district heating for existing buildings in various stages of refurbishment

    DEFF Research Database (Denmark)

    Brand, Marek; Svendsen, Svend

    2013-01-01

    and, for 98% of the year, to below 60 °C. However for the temperatures below 60 °C a low-temperature DH substation is required for DHW (domestic hot water) heating. This research shows that renewable sources of heat can be integrated into the DH system without problems and contribute to the fossil...

  3. Conversion of individual natural gas to district heating

    DEFF Research Database (Denmark)

    Möller, Bernd; Lund, Henrik

    2010-01-01

    Replacing individual natural gas heating with district heating based to increasing shares of renewable energy sources may further reduce CO2-emissions in the Danish Building mass, while increasing flexibility of the energy system to accommodate significantly larger amounts of variable renewable...... energy production. The present paper describes a geographical study of the potential to expand district heating into areas supplied with natural gas. The study uses a highly detailed spatial database of the built environment, its current and potential future energy demand, its supply technologies and its...... location relative to energy infrastructure. First, using a spatially explicit economic model, the study calculates the potentials and costs of connection to expanded district heating networks by supply technology. Then a comprehensive energy systems analysis is carried out to model how the new district...

  4. District heating by radiant heat recovery from cement kilns

    Energy Technology Data Exchange (ETDEWEB)

    Caputo, Antonio C.; Palumbo, Mario; Pelagagge, Pacifico M.; Salini, Paolo [University of L' Aquila, Monteluco (Italy). Dept. of Mechanical, Energy and Management Engineering]. E-mail: caputo@ing.univaq.it; palumbo@ing.univaq.it; pelmar@ing.univaq.it; salini@ing.univaq.it

    2008-07-01

    Heat loss from rotary kilns may represent a significant percentage of the total energy input especially in high energy-intensive industrial sectors such as cement production. In this paper the technical and economic feasibility of recovering radiant heat lost through the kiln surface, by means of a secondary external shell acting as a heat exchanger for a transfer fluid, is evaluated for district heating purposes. At first the system architecture is outlined and a technical and economical model addressing both the performances and cost estimation for the heat exchanger and the district heating network is developed. Subsequently, a parametric profitability analysis is carried out with reference to some relevant parameters characterizing the available recoverable waste heat and the size of the heat distribution network, namely the distance between kiln and user area and extension of the district heating network. This is made to obtain a mapping of the conditions were the proposed heat recovery system is economically feasible. In the paper it is demonstrated that the relevant heat consumption of cement production may make the district heating option for heat recovery a viable one even in case of low density of inhabitants in the surroundings of the plant. Furthermore significant fuel savings and emission reductions are achieved respect the adoption of traditional residential boilers. author)

  5. Industrial Heat Pump for a High Temperature District Heating Application

    DEFF Research Database (Denmark)

    Poulsen, Claus Nørgaard

    2013-01-01

    by excess thermal energy from thermal solar panels. An industrial heat pump system using the natural refrigerant ammonia, is extracting the thermal energy from the storage when needed, and produce hot water at 85°C, for the district heating grid. The heat pump also acts as contributor to electricity grid...

  6. Economic and environmental efficiency of district heating plants

    DEFF Research Database (Denmark)

    Agrell, Per J.; Bogetoft, Peter

    2005-01-01

    heat, have arbitrary valuation.This study concerns the most developed European district heating and cogeneration system, the Danish.By assessing environmental and economic ef¿ciency, the impact of governmental, market and managerial imperfections are estimated.The principal methodological base...

  7. District heating in Italy; Genesi ed evoluzione del district heating in Italia

    Energy Technology Data Exchange (ETDEWEB)

    Sacchi, E. [Milan Politecnico (Italy). Dip. di energetica

    1998-12-01

    The legislative act establishing the electric monopoly virtually shut out the district heating associated with electricity cogeneration, while other laws, issued to counteract the effects of oil shocks, allowed municipal utilities to do so. Thus, district heating has experienced some development, though well below its possibilities. The article analyses the reasons for this lagging, reports district heating data and projects its forecasts against the Kyoto Protocol objectives. [Italiano] La legge istitutiva del monopolio elettrico ha di fatto impedito il district heating associato alla cogenerazione di elettricita`, mentre le leggi tese a contrastare gli effetti delle crisi energetiche lo hanno reso possibile ad opera delle aziende municipali: un certo sviluppo si e` verificato, seppure ben al di sotto delle possibili potenzialita`. L`articolo analizza i motivi di questo rallentato sviluppo, riporta i dati del district heating e ne proietta le previsioni lungo gli obiettivi del Protocollo di Kyoto.

  8. Demand side management for smart district heating

    DEFF Research Database (Denmark)

    Big, Oovidiu; Li, Hongwei; Svendsen, Svend

    2015-01-01

    constant. The results show that by the extensive renovation the energy consumption and the peak load could be reduced with more than 55% for two heating systems: radiant floor heating and radiators convective heating. Light renovation case has the peak load and energy consumption decreased with values...... between 25% and 35%. By making the light renovation, the heating system needs a minimum supply water temperature of 58ºC in order to cover the thermal comfort. Through extensive renovation, the supply water temperature could be reduced to 50ºC which makes it possible to transform the District Heating...

  9. Optimising corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.; Andersen, A.

    2002-01-01

    is to improve the quality control in district heating systems by corrosion monitoring. In Danish systems electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR), high-sensitive electrical resistance (ER) technology, crevice corrosion probes, as well as weight loss coupons......A three-year project - financially supported by the Nordic Industrial Fund - on monitoring of corrosion in district heating systems has been initiated with participation of researchers and industrial partners in Denmark, Finland, Iceland, Norway and Sweden. The primary objective of the project...... will be tested. Laboratory studies as well as on-line measurements in district heating systems using probes in a specially designed sidestream unit are included in the practical part of the project....

  10. Geothermal district heating: basics to success

    Energy Technology Data Exchange (ETDEWEB)

    Lunis, B.C.

    1985-01-01

    A district heating system using geothermal energy is a viable and economic option in many locations. A successful system, however, is dependent upon a variety of factors, and it is the purpose of this presentation to accent those items that are proving to have significant impact upon the successful operation of geothermal district heating systems. (These lessons can also apply to other sources of energy.) The six major basics to success that are discussed in this paper are economic viability, an adequate geothermal resource, simplicity of design, a closed loop system, a local champion, and good public relations.

  11. Corrosion Fatigue in District Heating Water Tanks

    DEFF Research Database (Denmark)

    Maahn, Ernst Emanuel

    1996-01-01

    Three candidate materials for construction of buffer tanks for district heating water have been tested for corrosion fatigue properties in a district heating water environment. The investigation included Slow Strain Rate Testing of plain tensile specimens, crack initiation testing by corrosion...... fatigue of plain tensile specimens and crack growth rate determination for Compact Tensile Specimens under corrosion fatigue conditions. The three materials are equal with respect to stress corrosion sensibility and crack initiation. Crack growth rate is increased with a factor of 4-6 relative to an inert...

  12. Houses adapted for district heating; Det fjaerrvaermeanpassade smaahuset

    Energy Technology Data Exchange (ETDEWEB)

    Walletun, Haakan; Zinko, Heimo [ZW Energiteknik AB, Nykoeping (Sweden)

    2004-07-01

    This report deals with an analysis of new types of heat loads for detached houses to be connected to district heating nets. The reason for that is that higher head loads would make the installation of a local heat distribution system economic. Therefore, the investigation studies different ways for increasing the district heating loads which for a normal detached house is about 20,000 kWh. This can be done by the following ways: a) District heating is replacing electricity b) District heating improves the comfort situation of the house c) The use of a simple heat source such as district heating creates new needs. In this report, an analysis of the energy potential and of economical aspects for different load types within these three categories is carried out. To category a) belongs whiteware such as washing machine, tumble-drier, dishwasher and absorption refrigerator. Among them is dishwasher an existing and washing machine a potentially existing product to find their way into detached houses. In addition, the tumble-drier exists, but only for larger applications (multi-family houses and laundry services). The increase of district heating load by these products will totally be 1,700 kWh per year. The introduction of air-conditioning systems based on absorption cooling (category b) can increase the district heating load in a detached house by about 850 kWh per year. Air-conditioning systems based on absorption techniques can become more common earlier than absorption refrigerators because such systems are already tested in a large number of demonstration projects. Load types according to category c) can also be of interest for the increase use of district heating in detached houses. To this category belongs melting of snow and ice on doorways and carports, heating devices for motor- and car pre-heaters, sauna and outdoor bath tube. With the exception of the sauna should those systems be connected to an secondary glycol circuit. The new energy load potential is

  13. Houses adapted for district heating; Det fjaerrvaermeanpassade smaahuset

    Energy Technology Data Exchange (ETDEWEB)

    Walletun, Haakan; Zinko, Heimo [ZW Energiteknik AB, Nykoeping (Sweden)

    2004-07-01

    This report deals with an analysis of new types of heat loads for detached houses to be connected to district heating nets. The reason for that is that higher head loads would make the installation of a local heat distribution system economic. Therefore, the investigation studies different ways for increasing the district heating loads which for a normal detached house is about 20,000 kWh. This can be done by the following ways: a) District heating is replacing electricity b) District heating improves the comfort situation of the house c) The use of a simple heat source such as district heating creates new needs. In this report, an analysis of the energy potential and of economical aspects for different load types within these three categories is carried out. To category a) belongs whiteware such as washing machine, tumble-drier, dishwasher and absorption refrigerator. Among them is dishwasher an existing and washing machine a potentially existing product to find their way into detached houses. In addition, the tumble-drier exists, but only for larger applications (multi-family houses and laundry services). The increase of district heating load by these products will totally be 1,700 kWh per year. The introduction of air-conditioning systems based on absorption cooling (category b) can increase the district heating load in a detached house by about 850 kWh per year. Air-conditioning systems based on absorption techniques can become more common earlier than absorption refrigerators because such systems are already tested in a large number of demonstration projects. Load types according to category c) can also be of interest for the increase use of district heating in detached houses. To this category belongs melting of snow and ice on doorways and carports, heating devices for motor- and car pre-heaters, sauna and outdoor bath tube. With the exception of the sauna should those systems be connected to an secondary glycol circuit. The new energy load potential is

  14. District Heating Systems Performance Analyses. Heat Energy Tariff

    Science.gov (United States)

    Ziemele, Jelena; Vigants, Girts; Vitolins, Valdis; Blumberga, Dagnija; Veidenbergs, Ivars

    2014-12-01

    The paper addresses an important element of the European energy sector: the evaluation of district heating (DH) system operations from the standpoint of increasing energy efficiency and increasing the use of renewable energy resources. This has been done by developing a new methodology for the evaluation of the heat tariff. The paper presents an algorithm of this methodology, which includes not only a data base and calculation equation systems, but also an integrated multi-criteria analysis module using MADM/MCDM (Multi-Attribute Decision Making / Multi-Criteria Decision Making) based on TOPSIS (Technique for Order Performance by Similarity to Ideal Solution). The results of the multi-criteria analysis are used to set the tariff benchmarks. The evaluation methodology has been tested for Latvian heat tariffs, and the obtained results show that only half of heating companies reach a benchmark value equal to 0.5 for the efficiency closeness to the ideal solution indicator. This means that the proposed evaluation methodology would not only allow companies to determine how they perform with regard to the proposed benchmark, but also to identify their need to restructure so that they may reach the level of a low-carbon business.

  15. Optimization of a local district heating plant under fuel flexibility and performance

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse; From, Niels

    2011-01-01

    Brovst is a small district in Denmark. Based on the case of Brovst, this paper analyses the role of district heating in future Renewable Energy Systems. The present use of fossil fuels in the Brovst DHP (district heating plant) represents an increasing environmental and climate-related load. So, ...

  16. Demand side management for smart district heating

    DEFF Research Database (Denmark)

    Big, Oovidiu; Li, Hongwei; Svendsen, Svend

    2015-01-01

    The influence on the district heating network design and operation by using the energy storage capability inside the building is studied on different types of buildings under Danish climate. The building envelope has significant role in buildings energy consumption but also in building time const...

  17. District heating in Finland 1997. Statistics; Kaukolaempoetilasto 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    The statistical data of district heating in Finland is collected and distributed yearly by the Finnish District Heating Association. The information was collected by a survey, in which 122 members and 43 utilities outside the membership participated. In the end of 1997 the association included 127 member utilities selling district heating

  18. Low Temperature District Heating Consumer Unit with Micro Heat Pump for Domestic Hot Water Preparation

    DEFF Research Database (Denmark)

    Zvingilaite, Erika; Ommen, Torben Schmidt; Elmegaard, Brian

    2012-01-01

    In this paper we present and analyse the feasibility of a district heating (DH) consumer unit with micro heat pump for domestic hot water (DHW) preparation in a low temperature (40 °C) DH network. We propose a micro booster heat pump of high efficiency (COP equal to 5,3) in a consumer DH unit...... in order to boost the temperature of the district heating water for heating the DHW. The paper presents the main designs of the suggested system and different alternative micro booster heat pump concepts. Energy efficiency and thermodynamic performance of these concepts are calculated and compared....... The results show that the proposed system has the highest efficiency. Furthermore, we compare thermodynamic and economic performance of the suggested heat pump-based concept with different solutions, using electric water heater. The micro booster heat pump system has the highest annualised investment (390 EUR...

  19. Consumer Unit for Low Energy District Heating Net

    DEFF Research Database (Denmark)

    Paulsen, Otto; Fan, Jianhua; Furbo, Simon

    2008-01-01

    A low energy/ low temperature consumer installation is designed and analyzed. The consumer type is a low energy single family house 145 m2 with annual energy consumption in the range of 7000 kWh, incl. domestic hot water in a 2800 degree day climate. The network is an extreme low temperature system...... to reduce heat loss in the network. The consumer’s installation is a unit type with an accumulation tank for smoothing the heat load related to the domestic hot water. The building heat load is delivered by an under-floor heating system. The heavy under-floor heating system is assumed to smooth the room...... heat load on a daily basis, having a flow temperature control based on outdoor climate. The unit is designed for a near constant district heating water flow. The paper describes two concepts. The analyses are based on TRNSYS (Klein et al., 2006) simulation, supplied with laboratory verification...

  20. Procedures for selecting and buying district heating equipment. Sofia district heating. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    The aim of this Final Report, prepared for the project `Procedures for Selecting and Buying DistRict Heating Equipment - Sofia District Heating Company`, is to establish an overview of the activities accomplished, the outputs delivered and the general experience gained as a result of the project. The main objective of the project is to enable Sofia District Heating Company to prepare specifications and tender documents, identify possible suppliers, evaluate offers, etc. in connection with purchase of district heating equipment. This objective has been reached by using rehabilitation of sub-stations as an example requested by Sofia DH. The project was originally planned to be finalized end of 1995, but due to the extensions of the scope of work, the project has been prolonged until end 1997. The following main activities were accomplished: Preparation of a detailed work plan; Collection of background information; Discussion and advice about technical specifications and tender documents for sub-station rehabilitation; Input to terms of reference for a master plan study; Input to technical specification for heat meters; Collection of ideas for topics and examples related to dissemination of information to consumers about matters related to district heating consumption. (EG)

  1. District heating in energetic and environmental politics

    Energy Technology Data Exchange (ETDEWEB)

    Associazione Italiana di Riscaldamento Urbano

    1989-05-01

    A review is made of what was said at the Third Bi-annual Convention (Reggio Emilia, 24-25/11/88) of AIRU (the Italian Association for District Heating). In general, the seven papers presented dealt with the following points: the technology of primary energy supply, thermal energy production, energy distribution to users, environmental engineering and socio-economic factors. Emphasis was given to the themes: district heating in Italy within the framework of the 1988 National Energy Plan and the impact on energy marketing due to the future free trade system planned for the E.E.C. in 1992. A critical analysis is made of: forecasts of primary energy demand for the year 2000, plans for the reduction of dependency on foreign supplied petroleum, the promotion of the increased use of natural gas and methane and overall energy conservation measures as called for by the National Energy Plan.

  2. Water chemistry in heat and cold supply (district heating/cooling)

    Energy Technology Data Exchange (ETDEWEB)

    Deelen-Bremer, Marga van; Vos, Frank de; Heijboer, Rob [KEMA Nederland B.V. (Netherlands)

    2010-07-01

    District heating is seen as an important pillar in the CO{sub 2} reduction. Since the Kyoto protocol with the target for reduction of greenhouse gases, a renewed interest in district heating is visible. District heating and increasingly district cooling can be used for heating/cooling of houses, but also for large buildings and greenhouses. Combined heat and power (CHP), waste incinerator, but also rest heat of industry can provide the heat for district heating. On the other hand cold surface water, groundwater, but also rest heat can be used for district cooling. With the growing heat/cold supply market, also an even larger growth in cases of damages in district heating systems is wittnessed. Damages were chemistry can play an preventing role. A good conditioning of the district heating water, combined with proper monitoring, will safeguard the integrity of the system. (orig.)

  3. Thermal performance of solar district heating plants in Denmark

    DEFF Research Database (Denmark)

    Furbo, Simon; Perers, Bengt; Bava, Federico

    2014-01-01

    The market for solar heating plants connected to district heating systems is expanding rapidly in Denmark. It is expected that by the end of 2014 the 10 largest solar heating plants in Europe will be located in Denmark. Measurements from 23 Danish solar heating plants, all based on flat plate solar...... collectors mounted on the ground, shows measured yearly thermal performances of the solar heating plants placed in the interval from 313 kWh/m² collector to 493 kWh/m² collector with averages for all plants of 411 kWh/m² collector for 2012 and 450 kWh/m² collector for 2013. Theoretical calculations show...... of the cost/performance ratio for solar collector fields, both with flat plate collectors and with concentrating tracking solar collectors. It is recommended to continue monitoring and analysis of all large solar heating plants to document the reliability of the solar heating plants. It is also recommended...

  4. Design of serially connected district heating heat pumps utilising a geothermal heat source

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    The design of two heat pumps (HP), connected in series, was investigated for operation in the district heating (DH) network of the Greater Copenhagen area, Denmark. The installation was dimensioned to supply 7.2 MW of heat at a temperature of 85 °C. The heat pumps utilise a geothermal heat source...

  5. Kaliningrad regional district heating network 2004-2006. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    This report concerns: Kaliningrad Regional District Heating Network project which was implemented from 2004 to 2006. The task of the project was to establish and operate an association for district heating companies in the region in order to transfer and distribute district heating know-how to the sector and through activities strengthen the sector. The long term aim was to contribute to establishment of an association to continue as a real association for the heat supply companies in the region. (au)

  6. Long-term impacts of heat demand reductions within the Aarhus district heating area

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    the current heat price that is taken into account. Often the long-term costs are not reflected in the heat price and since the benefits of investing in heat saving measures last for a long time, the decision should be based on long-term planning taking reinvestments in production capacity and distribution...... is decided on the basis of short-term decisions based on the payback time of the investments compared to the current heat price. Since a large share of the Danish buildings are within district heating areas with a low marginal heat price, heat saving measures have a long payback time if it is only...... in the expected production facilities of 2016 and the implementation of heat savings in three different scenarios, where heat savings of 50% are carried out gradually until 2050. The costs in all scenarios are compared though net present value calculations based on socio-economic costs. The results show...

  7. Korean district heating. Part 2: Investigation of the consumption pattern in a substation at Korea District Heating Corporation at the turn of the year 1994/95

    Energy Technology Data Exchange (ETDEWEB)

    Joensson, Mats; Olsson, Nils

    1996-05-01

    This thesis, which is the second part of two, analyses the consumption pattern and the conditions for district heating in the Republic of Korea at the turn of the year 1994-95. It is based on a study made in Seoul at Korea District Heating Corporation which is the largest district heating utility in Korea. District heating was introduced in the 80s because of the environmental advantages. In 1994 KDHC provided 340 000 households with district heating. KDHC receives most of its thermal energy from combined heat and power plants which use natural gas as fuel. One substation was chosen for the investigation and temperature, flow, and pressure were measured. A typical Korean substation has heat exchangers connected in parallel in only one step and the apartment complexes use floor heating for internal heating. The space heating load shows a linear relation to the outdoor temperature. The hot tap-water consumption shows a highly varying pattern with peak loads in the morning and evening. There were also an oscillating pattern for some of the temperatures and flows caused by poor regulation. DH suits very well to Korea with its climate and the overpopulated cities. KDHC:s expansion will help to make Korea one of the leading countries in modern district heating. 10 refs, 36 figs, 11 tabs

  8. Challenges in Smart Low-Temperature District Heating Development

    DEFF Research Database (Denmark)

    Li, Hongwei; Wang, Stephen Jia

    2014-01-01

    Previous research and development shows that low temperature district heating (LTDH) system is economic feasible for low energy buildings and buildings at sparse areas. Coupling with reduced network temperature and well-designed district heating (DH) networks, LTDH can reduce network heat loss...

  9. Geothermal district heating system feasibility analysis, Thermopolis, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Goering, S.W.; Garing, K.L.; Coury, G.; Mickley, M.C.

    1982-04-26

    The purpose of this study is to determine the technical and economic feasibility of constructing and operating a district heating system to serve the residential, commercial, and public sectors in Thermopolis. The project geothermal resource assessment, based on reviews of existing information and data, indicated that substantial hot water resources likely exist in the Rose Dome region 10 miles northeast of Thermopolis, and with quantities capable of supporting the proposed geothermal uses. Preliminary engineering designs were developed to serve the space heating and hot water heating demands for buildings in the Thermopolis-East Thermopolis town service area. The heating district design is based on indirect geothermal heat supply and includes production wells, transmission lines, heat exchanger units, and the closed loop distribution and collection system necessary to serve the individual customers. Three options are presented for disposal of the cooled waters-reinjection, river disposal, and agricultural reuse. The preliminary engineering effort indicates the proposed system is technically feasible. The design is sized to serve 1545 residences, 190 businesses, and 24 public buildings. The peak design meets a demand of 128.2 million Btu at production rates of 6400 gpm.

  10. Feasibility analysis of geothermal district heating for Lakeview, Oregon

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-23

    An analysis of the geothermal resource at Lakeview, Oregon, indicates that a substantial resource exists in the area capable of supporting extensive residential, commercial and industrial heat loads. Good resource productivity is expected with water temperatures of 200{degrees}F at depths of 600 to 3000 feet in the immediate vicinity of the town. Preliminary district heating system designs were developed for a Base Case serving 1170 homes, 119 commercial and municipal buildings, and a new alcohol fuel production facility; a second design was prepared for a downtown Mini-district case with 50 commercial users and the alcohol plant. Capital and operating costs were determined for both cases. Initial development of the Lakeview system has involved conducting user surveys, well tests, determinations of institutional requirements, system designs, and project feasibility analyses. A preferred approach for development will be to establish the downtown Mini-district and, as experience and acceptance are obtained, to expand the system to other areas of town. Projected energy costs for the Mini-district are $10.30 per million Btu while those for the larger Base Case design are $8.20 per million Btu. These costs are competitive with costs for existing sources of energy in the Lakeview area.

  11. Reno Industrial Park geothermal district heating system

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1997-04-01

    Ten miles south of Reno, on U.S. 395 near the junction of the road to historic Virginia City, is Steamboat Hot Springs, a popular stop for travelers since the mid-1800s. Legend has it that Mark Twain named the geothermal area because it looked and sounded like a chugging Mississippi River paddle-wheeler. It is said when he first saw the steam rising from the ground he exclaimed, {open_quotes}Behold! A Steamboat in the desert.{close_quotes} Over the years, the area has been used for its relaxing and curative qualities by Indians, settlers, and geothermal experts. Since the mid-1980s five geothermal power plants have been built at Steamboat Springs and in December 1996 it was announced that the proposed largest geothermal district heating system in the U.S. would supply an industrial park in the area. The active geothermal area is located within the north-south trending graben like trough between the Carson and Virginia Ranges at the southern end of Truckee Meadows. Hot springs and other geothermal features occur over an area of about one square mile. The mid-basin location is controlled by faulting more or less parallel to the major mountain-front faults. It is believed that the heat source for the system is a cooling magmatic body at depth. The Steamboat geothermal area consists of a deep, high-temperature (215{degrees}C to 240{degrees} C) geothermal system, a shallower, moderate-temperature (160{degrees}C to 18{degrees} C) system, and a number of shallow low-temperature (30{degrees}C to 80{degrees}C) subsystems. The higher temperature systems are used for electric-power generation. It is proposed that the exit fluids from the electric power plants be used for the geothermal district heating system.

  12. Primary energy and the competitiveness of district heating. Final report; Primaeaerienergia ja kaukolaemmoen kilpailukyky. Loppuraportti

    Energy Technology Data Exchange (ETDEWEB)

    Broeckl, M.; Pesola, A.; Vanhanen, J.

    2010-09-15

    Primary energy is an important topic when discussing the most efficient ways to heat buildings. It has been suggested that in the new building codes the energy consumption of buildings should be evaluated based on either their primary energy consumption or the emission of greenhouse gases. This study has an objective to analyze how the district heating primary energy coefficient, which is possibly going to be used in the new building codes, can be defined with different methods. The study also has an objective to evaluate how the competitiveness of district heating is influenced, if the future building codes are based on different values of primary energy coefficients for electricity, heating fuels and district heating. The weighting of the consumption of different energy forms in the building codes has a great deal of influence on the competitiveness of various energy forms. The way in which energy coefficients are defined is important for the competitiveness of district heating solutions when comparing it to other forms of heating, such as electricity based heating systems, e.g. various heat pumps. Similarly important issue is how the energy-coefficients of wood based heating forms, prevalent especially in the countryside, are defined. On the other hand, the definition of primary coefficients is only one aspect which influences the competitiveness of different heating solutions. The investment costs required, operating costs as well as ease of use play an important role in the choice of heating solutions. It has to be noted that the primary energy coefficients for district heating and electricity are a function of time and place. Renewable fuels also have a big impact on the energy coefficients especially when used for combined heat and electricity production. This means that in reality district heating can't be described completely unambiguously with a standard coefficient. There are in fact several ways to define and calculate primary energy coefficients

  13. Geothermal district heating in Turkey: The Gonen case study

    Energy Technology Data Exchange (ETDEWEB)

    Oktay, Zuhal [Department of Mechanical Engineering, Faculty of Engineering and Architecture, Balikesir University, 10100 Cagis-Campus, Balikesir (Turkey); Aslan, Asiye [Gonen Vocational College, Balikesir University, Gonen-Balikesir (Turkey)

    2007-04-15

    The status of geothermal district heating in Turkey and its future prospects are reviewed. A description is given of the Gonen project in Balikesir province, the first system to begin citywide operation in the country. The geology and geothermal resources of the area, the history of the project's development, the problems encountered, its economic aspects and environmental contributions are all discussed. The results of this and other such systems installed in Turkey have confirmed that, in this country, heating an entire city based on geothermal energy is a significantly cleaner, cheaper option than using fossil fuels or other renewable energy resources. (author)

  14. Efficient district heating in the future energy system. Final report; Effektiv fjernvarme i fremtidens energisystem. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    2009-07-01

    The purpose of this project is to illustrate how district heating can develop its role in the future Danish energy system, for example by reducing energy losses and the dynamic use of common technologies such as cogeneration and heat storage, and less widespread technologies such as heat pumps, geothermal heating, and cooling. The aim is also to analyse how electricity and district heating can interact more effectively, and to point out how framework conditions are important for district heating's continued development and efficiency. In the project, a linear optimization model is developed and applied as to analyse the interaction between district heating supply on the one hand, and energy savings, CO{sub 2} targets, wind power and the international electricity market on the other hand. Furthermore, more close-case operational analyses of district heating systems have been made in Ringkoebing and the metropolitan area, based on data from the district heating companies. Finally, a wide range of challenges for district heating in the long term were discussed and analysed during meetings with the project's reference group, including the need for development and demonstration projects. (ln)

  15. Efficient district heating in the future energy system. Final report; Effektiv fjernvarme i fremtidens energisystem. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    2009-07-01

    The purpose of this project is to illustrate how district heating can develop its role in the future Danish energy system, for example by reducing energy losses and the dynamic use of common technologies such as cogeneration and heat storage, and less widespread technologies such as heat pumps, geothermal heating, and cooling. The aim is also to analyse how electricity and district heating can interact more effectively, and to point out how framework conditions are important for district heating's continued development and efficiency. In the project, a linear optimization model is developed and applied as to analyse the interaction between district heating supply on the one hand, and energy savings, CO{sub 2} targets, wind power and the international electricity market on the other hand. Furthermore, more close-case operational analyses of district heating systems have been made in Ringkoebing and the metropolitan area, based on data from the district heating companies. Finally, a wide range of challenges for district heating in the long term were discussed and analysed during meetings with the project's reference group, including the need for development and demonstration projects. (ln)

  16. Smart energy systems and 4th generation district heating

    DEFF Research Database (Denmark)

    Lund, Henrik; Mathiesen, Brian Vad

    2015-01-01

    District heating and cooling are here to stay, but the district heating technology has to change. It has to adjust to the requirements of a future smart energy development. Therefore, research is essential, but not only research in university laboratories. Demonstration projects and innovation...

  17. District Heating in Areas with Low Energy Houses

    DEFF Research Database (Denmark)

    Tol, Hakan Ibrahim

    houses there being considered for renovation to houses of a low-energy class, and due to the existing heat-supply energy infrastructure there being a natural gas grid. The third case study carried out aimed at developing energy conversion systems based on use of renewable energy sources that were...... in Denmark. The second case study was aimed at solving another regional energy planning scheme, one concerned with already existing houses, the heat requirements of which were currently being met by use of a natural gas grid or a conventional high-temperature district heating network. The idea considered...... to study the improvement in efficiency achieved by use of multi-generation systems, (ii) various types of energy conversion systems, such as single-generation, cogeneration, and multi-generation systems, (iii) the long-term storage of heat energy to cope with the mismatch between the energy production from...

  18. Performance Analysis of a Hybrid District Heating System: a Case Study of a Small Town in Croatia

    Directory of Open Access Journals (Sweden)

    Robert Mikulandric

    2015-09-01

    Full Text Available Hybridisation of district heating systems can contribute to more efficient heat generation through cogeneration power plants or through the share increase of renewable energy sources in total energy consumption while reducing negative aspects of particular energy source utilisation. In this work, the performance of a hybrid district energy system for a small town in Croatia has been analysed. Mathematical model for process analysis and optimisation algorithm for optimal system configuration has been developed and described. The main goal of the system optimisation is to reduce heat production costs. Several energy sources for heat production have been considered in 8 different simulation cases. Simulation results show that the heat production costs could be reduced with introduction of different energy systems into an existing district heating system. Renewable energy based district heating systems could contribute to heat production costs decrease in district heating systems up to 30% in comparison with highly efficient heat production technologies based on conventional fuels.

  19. A multicriteria approach to evaluate district heating system options

    Energy Technology Data Exchange (ETDEWEB)

    Ghafghazi, S.; Sowlati, T. [Department of Wood Science, University of British Columbia, 2931-2424 Main Mall, Vancouver, BC (Canada); Sokhansanj, S. [Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC (Canada); Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Melin, S. [Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC (Canada); Delta Research Corporation, Delta, BC (Canada)

    2010-04-15

    District energy systems, in which renewable energy sources may be utilized, are centralized systems to provide energy to residential and commercial buildings. The aim of this paper is to evaluate and rank energy sources available for a case of district heating system in Vancouver, Canada, based on multiple criteria and the view points of different stakeholders, and to show how communication would affect the ranking of alternatives. The available energy sources are natural gas, biomass (wood pellets), sewer heat, and geothermal heat. The evaluation criteria include GHG emissions, particulate matter emissions, maturity of technology, traffic load, and local source. In order to rank the energy options the PROMETHEE method is used. In this paper, two different scenarios were developed to indicate how the communication between the stakeholders would affect their preferences about criteria weights and would change the ranking of alternatives. The result of this study shows that without communication the best energy source for the considered district energy system is different for different stakeholders. While, addressing concerns through efficient communication would result in a general consensus. In this case, wood pellet is the best energy alternative for all the stakeholders. (author)

  20. Energy and exergy analysis of low temperature district heating network

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    2012-01-01

    Low temperature district heating with reduced network supply and return temperature provides better match of the low quality building heating demand and the low quality heating supply from waste heat or renewable energy. In this paper, a hypothetical low temperature district heating network...... is designed to supply heating for 30 low energy detached residential houses. The network operational supply/return temperature is set as 55 °C/25 °C, which is in line with a pilot project carried out in Denmark. Two types of in-house substations are analyzed to supply the consumer domestic hot water demand....... The space heating demand is supplied through floor heating in the bathroom and low temperature radiators in the rest of rooms. The network thermal and hydraulic conditions are simulated under steady state. A district heating network design and simulation code is developed to incorporate the network...

  1. Uncertainties in the daily operation of a district heating plant

    DEFF Research Database (Denmark)

    Sorknæs, Peter

    Studies have found that district heating (DH) systems should play an important role in future sustainable energy systems, but that DH has to adapt to lower heat demands. This means adapting to reduced operation hours for units essential for DHs integration in other parts of the energy system...... Ringkøbing District Heating is used as a case to investigate what costs market uncertainties can incur on a DH plant. It is found that the market uncertainties in a 4 months simulated period increased Ringkøbing District Heatings costs by less than 1%. Several factors are however not included in this paper....

  2. Smart district heating system and its possibilities. Final report; Aelykaes kaukolaempoejaerjestelmae ja sen mahdollisuudet. Loppuraportti

    Energy Technology Data Exchange (ETDEWEB)

    Pesola, A.; Broeckl, M.; Vanhanen, J.

    2011-11-15

    side management. Possibilities offered by smart technology are supported by pricing models that reward the customer actions that cuts the demand peaks. Operational environment of district heating develops continuously. Hence, energy companies need to openly consider new business models and possibilities related to these. It needs to be emphasized that competitive edge of district heating is, above all, the reliability and simplicity. Customers are used to receive heat based on instant necessity. That is why it is essential that customer perspective drives the planning and implementation of new services. This is the way to develop district heating sector in the right direction where both customer and the company achieve additional benefits and district heating preserves its competitiveness also in the future. (orig.)

  3. District heating: lifeblood system systematically modernised; Lebensnerv Fernwaerme gezielt modernisiert

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This article discusses the high potential available for the reduction of operating costs in the distribution of heat to consumers via district heating networks. The modernisation of the district heating system in the Black Sea Port of Konstanza, Rumania, is discussed. In particular, the renewal of the hot-water circulation pumps and the implementation of an automated system for the control and monitoring of 132 district heating transfer stations is described. The system's functions - the supply of space heating and domestic hot water preparation - are looked at, as is its load-dependent control system and its associated communication system. The new pump speed control system is quoted as being able to permit savings of up to 60% to be made. Finally, the contributions to protecting the environment resulting from the renewal of the district heating system are noted.

  4. Integration of space heating and hot water supply in low temperature district heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2016-01-01

    is required by the consumer. We study conventional district heating at different temperatures and compare the energy and exergetic efficiency and annual heating cost to solutions that utilize electricity for supplementary heating of domestic hot water in low temperature district heating. This includes direct...... electric heating and three heat pump solutions applying R134a and R744. The results show that conventional solutions at lowest possible temperature have the highest exergetic efficiency of 28% and lowest annual cost of € 690 for a 159 m2 house. The best low temperature system is an R134a heat pump with hot......District heating may supply many consumers efficiently, but the heat loss from the pipes to the ground is a challenge. The heat loss may be lowered by decreasing the network temperatures for which reason low temperature networks are proposed for future district heating. The heating demand...

  5. Casing free district heating pipes; Mantelfria fjaerrvaermeroer

    Energy Technology Data Exchange (ETDEWEB)

    Saellberg, Sven-Erik; Nilsson, Stefan [Swedish National Testing and Research Inst., Goeteborg (Sweden)

    2005-07-01

    Previous studies have shown that polyurethane insulation (PUR foam) on district heating pipes acts as protection against water if it is of good quality, i.e. free from cracks, cavities and other defects. On the other hand water vapour easily diffuses through PUR foam. However this is not a problem as long as the steel pipe is warmer than the surface layer, since the high temperature will prevent the vapour from condensating. What will happen with the insulation of a casing free district heating pipe where the ground water level occasionally reaches above the pipe has not been studied in detail. The current project has studied to what extent moisture enters the PUR foam insulation of two approximately one meter long district heating pipes without casing which have been in the ground for four years. Occasionally, the ground-water has entirely covered the pipes. In addition, the foam has been studied with respect to damage from the surrounding backfill material. Test specimens were taken out of the casing free pipes and were analysed with respect to moisture content. Additional measurements were done with a moisture indicator, and the electric resistance between the steel pipes and the four surveillance wires in each pipe was measured. The results from the various measurement techniques were the compared. The results show that the PUR foam remains dry as long as the service pipe is hot if no defects, such as crack and cavities, are present. Close to the service pipe, the foam actually dries out over time. The moisture content of the middle layer remains more or less constant. Only the colder parts on the outside exhibit an increase in moisture content. It was also seen that defects may lead to water ingress with subsequent humidification of the foam. However, the damaged foam area is limited. This is not the case for a regular pipe with a vapour tight casing, where experience show that moisture tend to spread along the pipe. The pipes were buried in sand and no

  6. Evaluation of thermal energy storage for the proposed Twin Cities District Heating system. [using cogeneration heat production and aquifiers for heat storage

    Science.gov (United States)

    Meyer, C. F.

    1980-01-01

    The technical and economic feasibility of incorporating thermal energy storage components into the proposed Twin Cities District heating project was evaluated. The technical status of the project is reviewed and conceptual designs of district heating systems with and without thermal energy storage were compared in terms of estimated capital requirements, fuel consumption, delivered energy cost, and environmental aspects. The thermal energy storage system is based on cogeneration and the storage of heat in aquifers.

  7. Improving the performance of district heating systems by utilization of local heat boosters

    DEFF Research Database (Denmark)

    Falcone, A.; Dominkovic, D. F.; Pedersen, A. S.

    LTDH grid as they will have the strategical role of connecting the heating system with the electrical energy coming from the intermittent and fluctuating renewable energy sources such as wind and solar power. In this paper a case study of district heating system is presented and analysed. The goal......District Heating (DH) plays an important role into the Danish energy green transition towards the future sustainable energy systems. The new, 4 th generation district heating network, the so called Low Temperature District Heating (LTDH), tends to lower the supply temperature of the heat down to 40......-50°C with return temperatures of 20-30 °C. This kind of heating system has many advantages and among all of them, it allows utilization of the heat coming from low exergy heat sources, as well as to decrease the grid heat losses. Electrical energy driven heat sources are also integrated into the future...

  8. Application of Predictive Control in District Heating Systems

    DEFF Research Database (Denmark)

    Palsson, Olafur Petur; Madsen, Henrik; Søgaard, Henning Tangen

    1993-01-01

    In district heating systems, and in particular if the heat production cakes place at a combined heat and power (CHP) plant, a reasonable control strategy is to keep the supply temperature from the district heating plant as low as possible. However, the control is subject to some restrictions....... A district heating system is an example of a non-stationary system, and the model parameters have to be time varying. Hence, the classical predictive control theory has to be modified. Simulation experiments are performed in order to study the performance of modified predictive controllers. The systems ape......, for example, that the total heat requirement for all consumers is supplied at any time and each individual consumer is guaranteed some minimum supply temperature at any time. A lower supply temperature implies lower heat loss from the transport and the distribution network, and lower production costs...

  9. District heating and energy efficiency in detached houses of differing size and construction

    Energy Technology Data Exchange (ETDEWEB)

    Joelsson, Anna; Gustavsson, Leif [Ecotechnology, Department of Engineering, Physics and Mathematics, Mid Sweden University, SE-831 25 Oestersund (Sweden)

    2009-02-15

    House envelope measures and conversion of heating systems can reduce primary energy use and CO{sub 2} emission in the existing Swedish building stock. We analysed how the size and construction of electrically heated detached houses affect the potential for such measures and the potential for cogenerated district heating. Our starting point was two typical houses built in the 1970s. We altered the floor plans to obtain 6 houses, with heated floor space ranging between 100 and 306 m{sup 2}. One of the houses was also analysed for three energy standards with differing heat loss rates. CO{sub 2} emission, primary energy use and heating cost were estimated after implementing house envelope measures, conversions to other heating systems and changes in the generation of district heat and electricity. The study accounted for primary energy, including energy chains from natural resources to useful heat in the houses. We showed that conversion to district heating based on biomass, together with house envelope measures, reduced the primary energy use by 88% and the CO{sub 2} emission by 96%, while reducing the annual societal cost by 7%. The choice of end-use heating system was decisive for the primary energy use, with district heating being the most efficient. Neither house size nor energy standard did significantly change the ranking of the heating systems, either from a primary energy or an economic viewpoint, but did affect the extent of the annual cost reduction after implementing the measures. (author)

  10. Environmental and Thermal Performance of District Heating Pipes

    Energy Technology Data Exchange (ETDEWEB)

    Froeling, Morgan

    2002-06-01

    The introduction of district heating has reduced the environmental impact from local heat production in urban areas. However, in order to fit into a sustainable society, district heating must be continuously developed according to the increasing demands on activities in a society moving towards sustainability. Our technical improvements must result in environmental improvements. This thesis focuses on the environmental performance of the distribution system - the district heating pipes. The purpose of this research is to understand how the distribution system can be improved. The information presented in this thesis can be used to identify possibilities for improving the environmental performance of different life cycle phases of the distribution system as well as a baseline when evaluating new technical developments. The heat losses during use of the pipes are of large importance for the environmental impact of district heating pipes. Such heat losses can be modelled if the mass transfer parameters for gases in the polyurethane insulation and the polyethylene casing are known. The diffusion coefficients, the permeability coefficients and the solubility coefficients and their temperature dependence have been determined for cyclopentane, carbon dioxide, nitrogen, and oxygen. The same parameters have been studied for the blowing agent alternative HFC-365mfc at room temperature. The long-term thermal performance of district heating pipes has been modelled using effective permeabilities for the pipe construction. Environmental consequences of heat losses during the use phase of district heating pipes have been compared with the impacts from production of the pipes and from construction of the district heating network. The use of the district heating pipes is the most important of the studied life cycle phases. Thus, it is very important to minimise heat losses from the pipes. The heat losses will for some district heating pipes increase notably during use due to foam

  11. District heating and cooling technology selection and characterization. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Metz, P.D.; Catan, M.; Piraino, M.; Timmerman, R.W.; Gleason, J.

    1986-03-01

    This report describes the district heating and cooling (DHC) technology selection and characterization tasks performed under Part I of the project ''District Heating and Cooling Market Potential and Penetration Study'' for the USDOE. The purpose of this project is to determine the applicability of various DHC technologies to different community types and regions of the country. The results will be used by DOE to guide R and D program planning.

  12. Exergy and Energy Analysis of Low Temperature District Heating Network

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    Low temperature district heating (LTDH) with reduced network supply and return temperature provides better match of the low quality building thermal demand and the low quality waste heat supply. In this paper, an exemplary LTDH network was designed for 30 low energy demand residential houses, which...... is in line with a pilot project that is carrying out in Denmark with network supply/return temperature at 55oC/25 oC. The consumer domestic hot water (DHW) demand is supplied with a special designed district heating (DH) storage tank. The space heating (SH) demand is supplied with a low temperature radiator...

  13. District Heating Network Design and Configuration Optimization with Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Hongwei Li

    2013-12-01

    Full Text Available In this paper, the configuration of a district heating network which connects from the heating plant to the end users is optimized. Each end user in the network represents a building block. The connections between the heat generation plant and the end users are represented with mixed integer and the pipe friction and heat loss formulations are non-linear. In order to find the optimal district heating network configuration, genetic algorithm which handles the mixed integer nonlinear programming problem is chosen. The network configuration is represented with binary and integer encoding and is optimized in terms of the net present cost. The optimization results indicates that the optimal DH network configuration is determined by multiple factors such as the consumer heating load, the distance between the heating plant to the consumer, the design criteria regarding the pressure and temperature limitation, as well as the corresponding network heat loss.

  14. Low Temperature District Heating for Future Energy Systems

    DEFF Research Database (Denmark)

    Schmidt, Dietrich; Kallert, Anna; Blesl, Markus

    2017-01-01

    of the building stock. Low temperature district heating (LTDH) can contribute significantly to a more efficient use of energy resources as well as better integration of renewable energy (e.g. geothermal or solar heat), and surplus heat (e.g. industrial waste heat) into the heating sector. LTDH offers prospects......, such as combustible fuels, and minimising energy losses and irreversible dissipation. The paper presents the international co-operative work in the framework of the International Energy Agency (IEA), the Technology Cooperation Programme on District Heating and Cooling including Combined Heat and Power (DHC|CHP) Annex......The building sector is responsible for more than one third of the final energy consumption of societies and produces the largest amount of greenhouse gas emissions of all sectors. This is due to the utilisation of combustion processes of mainly fossil fuels to satisfy the heating demand...

  15. Design of A District Heating System Including The Upgrading of Residual Industrial Waste Heat

    NARCIS (Netherlands)

    Falcao, P.W.; Mesbah, A.; Suherman, M.V.; Wennekes, S.

    2005-01-01

    This study was aimed to evaluate the feasibility of using a waste heat stream from DSM for a District Heating System. A conceptual design was carried out with emphasis on the unit for upgrading the residual waste heat. Having reviewed heat pump technology, mechanical heat pump was found to be the be

  16. Design of A District Heating System Including The Upgrading of Residual Industrial Waste Heat

    NARCIS (Netherlands)

    Falcao, P.W.; Mesbah, A.; Suherman, M.V.; Wennekes, S.

    2005-01-01

    This study was aimed to evaluate the feasibility of using a waste heat stream from DSM for a District Heating System. A conceptual design was carried out with emphasis on the unit for upgrading the residual waste heat. Having reviewed heat pump technology, mechanical heat pump was found to be the

  17. Design of A District Heating System Including The Upgrading of Residual Industrial Waste Heat

    NARCIS (Netherlands)

    Falcao, P.W.; Mesbah, A.; Suherman, M.V.; Wennekes, S.

    2005-01-01

    This study was aimed to evaluate the feasibility of using a waste heat stream from DSM for a District Heating System. A conceptual design was carried out with emphasis on the unit for upgrading the residual waste heat. Having reviewed heat pump technology, mechanical heat pump was found to be the be

  18. Steady-state heat losses in pipes for low-energy district heating

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro; Li, Hongwei; Svendsen, Svend

    2010-01-01

    of low-energy DH systems. Various design concepts are considered in this paper: flexible pre-insulated twin pipes with symmetrical or asymmetrical insulation, double pipes, triple pipes. These technologies are potentially energyefficient and cost-effective solutions for DH networks in low-heat density......The synergy between highly energy efficient buildings and low-energy district heating (DH) systems is a promising concept for the optimal integration of energy saving policies and energy supply systems based on renewable energy (RE). Distribution heat losses represent a key factor in the design...... areas. We start with a review of theories and methods for steady-state heat loss calculation. Next, the article shows how detailed calculations with 2D-modeling of pipes can be carried out by means of computer software based on the finite element method (FEM). The model was validated by comparison...

  19. Biologically Inspired Optimization of Building District Heating Networks

    Directory of Open Access Journals (Sweden)

    Leiming Shang

    2013-07-01

    Full Text Available In this paper we show that a biologically inspired model can be successfully applied to problems of building optimal district heating network. The model is based on physiological observations of the true slime mold Physarumpolycephalum, but can also be used for path-finding in the complicated networks of mazes and road maps. A strategy of optimally building heating distribution network was guided by the model and a well-tuned ant colony algorithm and genetic algorithm. The results indicate that although there are not large-scale efficiency savings to be made, the biologically inspired amoeboid movement model is capable of finding results of equal or better optimality than a comparable ant colony algorithm and genetic algorithm.

  20. Impact assessment of biomass-based district heating systems in densely populated communities. Part II: Would the replacement of fossil fuels improve ambient air quality and human health?

    Science.gov (United States)

    Petrov, Olga; Bi, Xiaotao; Lau, Anthony

    2017-07-01

    To determine if replacing fossil fuel combustion with biomass gasification would impact air quality, we evaluated the impact of a small-scale biomass gasification plant (BRDF) at a university campus over 5 scenarios. The overall incremental contribution of fine particles (PM2.5) is found to be at least one order of magnitude lower than the provincial air quality objectives. The maximum PM2.5 emission from the natural gas fueled power house (PH) could adversely add to the already high background concentration levels. Nitrogen dioxide (NO2) emissions from the BRDF with no engineered pollution controls for NOx in place exceeded the provincial objective in all seasons except during summer. The impact score, IS, was the highest for NO2 (677 Disability Adjusted Life Years, DALY) when biomass entirely replaced fossil fuels, and the highest for PM2.5 (64 DALY) and CO (3 DALY) if all energy was produced by natural gas at PH. Complete replacement of fossil fuels by one biomass plant can result in almost 28% higher health impacts (708 DALY) compared to 513 DALY when both the current BRDF and the PH are operational mostly due to uncontrolled NO2 emissions. Observations from this study inform academic community, city planners, policy makers and technology developers on the impacts of community district heating systems and possible mitigation strategies: a) community energy demand could be met either by splitting emissions into more than one source at different locations and different fuel types or by a single source with the least-impact-based location selection criteria with biomass as a fuel; b) advanced high-efficiency pollution control devices are essential to lower emissions for emission sources located in a densely populated community; c) a spatial and temporal impact assessment should be performed in developing bioenergy-based district heating systems, in which the capital and operational costs should be balanced with not only the benefit to greenhouse gas emission

  1. Application of imitation steam'' systems to hot water district heating and cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Aalto, P.J.; Chen, D.B.

    1991-10-01

    Pequod Associates, Inc. and District Energy St. Paul, Inc. installed a pilot project of an innovative District Heating technology through a contract with the US DOE. This applied research was funded by the Energy Research and Development Act (94--163) for District Heating and Cooling Research. The experimental design is an intervention technique that permits hot water district heating systems to connect to buildings equipped with steam heating systems to connect to buildings equipped with steam heating systems. This method can substantially reduce conversion costs in many older buildings. The method circulates Imitation Steam, which is moist hot air, as a heating medium in standard steam radiators and steam heating coils. Based on the operation of the system during the 1989--90 and 1990--91 winter heating seasons, we conclude the following: the basic concept of using Imitation Steam was proved feasible. The performance of the system can be improved beyond the levels achieved in this installation. Imitation Steam did not cause significant corrosion in the piping system. The technology can be used by other district heating systems to lower conversion costs and increase market penetration. Among the additional benefits from this technology are: eliminating old, inefficient boilers; lower maintenance costs; improved fuel efficiency; reduced emissions.

  2. On-line corrosion monitoring in geothermal district heating systems

    DEFF Research Database (Denmark)

    Richter, S.; Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.

    2006-01-01

    General corrosion rates in the geothermal district heating systems in Iceland are generally low, of the magnitude 1 lm/y. The reason is high pH (9.5), low-conductivity (200 lm/y) and negligible dissolved oxygen. The geothermal hot water is either used directly from source or to heat up cold ground...

  3. District Heating Network Design and Configuration Optimization with Genetic Algorithm

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    2013-01-01

    and the pipe friction and heat loss formulations are non-linear. In order to find the optimal district heating network configuration, genetic algorithm which handles the mixed integer nonlinear programming problem is chosen. The network configuration is represented with binary and integer encoding...

  4. Smart energy systems and 4th generation district heating

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg; Lund, Henrik; Mathiesen, Brian Vad

    2016-01-01

    of Sustainable Energy Planning and Management. The editorial and the volume presents work on district heating system scenarios in Austria, grid optimisation using genetic algorithms and finally design of energy scenarios for the Italian Alpine town Bressanone-Brixen from a smart energy approach. © 2016, Aalborg......Energy systems are becoming increasingly complex, integrating across traditionally separate sectors such as transportation, heating, cooling and electricity. Integration through the use of district heating is the main topic of this editorial introducing volume 10 of the International Journal...

  5. Implementing Geothermal Plants in the Copenhagen District Heating System

    DEFF Research Database (Denmark)

    Jensen, Louise Overvad; Hallgreen, Christine Erikstrup; Larsen, Esben

    2003-01-01

    The possibility of implementing geothermal heating in the Copenhagen district-heating system is assessed. This is done by building up general knowledge on the geological factors that influence the development of useable geothermal resources, factors concerning the exploration and utilization...... Danish district heating system is financially sustainable. Added to the other advantages concerning flexibility and the environment, geothermal heating is considered to be a serious proposal for the future power and heating system in Eastern Denmark. Keywords: Geothermal plants, Electricity surplus...... of geothermal energy in Denmark as well as the Danish potential, which, in former investigations, has been found to be around 100.000 PJ annually, and the economical potential is less, about 15 PJ/year. Since a considerable amount of the Danish power supply is tied to weather and the demand for heating...

  6. Implementing Geothermal Plants in the Copenhagen District Heating System

    DEFF Research Database (Denmark)

    Jensen, Louise Overvad; Hallgreen, Christine Erikstrup; Larsen, Esben

    2003-01-01

    Danish district heating system is financially sustainable. Added to the other advantages concerning flexibility and the environment, geothermal heating is considered to be a serious proposal for the future power and heating system in Eastern Denmark. Keywords: Geothermal plants, Electricity surplus......The possibility of implementing geothermal heating in the Copenhagen district-heating system is assessed. This is done by building up general knowledge on the geological factors that influence the development of useable geothermal resources, factors concerning the exploration and utilization...... of geothermal energy in Denmark as well as the Danish potential, which, in former investigations, has been found to be around 100.000 PJ annually, and the economical potential is less, about 15 PJ/year. Since a considerable amount of the Danish power supply is tied to weather and the demand for heating...

  7. SUBSTATIONS OF DISTRICT HEATING SYSTEMS WITH PULSE COOLANT CIRCULATION

    Directory of Open Access Journals (Sweden)

    Andrey N. Makeev

    2017-01-01

    Full Text Available Abstract. Objectives The aim of the study is to generalise the results of the application of technologies and means for organising pulse coolant flow within a district heating system in order to increase its energy efficiency based on the organisation of local hydraulic shocks and the subsequent use of their energy to ensure the purification of heat energy equipment, intensify the heat transfer process and realise the possibility of transforming the available head from one hydraulic circuit to another. Methods Substations connecting the thermal power installations of consumers with heat networks via dependent and independent schemes are analytically generalised. The use of pulse coolant circulation is proposed as a means of overcoming identified shortcomings. Results Principal schemes of substations with pulse coolant circulation for dependent and independent connection of thermal power installations are detailed. A detailed description of their operation is given. The advantages of using pulse coolant circulation in substations are shown. The materials reflecting the results of the technical implementation and practical introduction of this technology are presented. Conclusion Theoretical analysis of the operation of the basic schemes of substations with pulse coolant circulation and the results of their practical application, as well as the materials of scientific works devoted to the use of the energy of a hydraulic impact and the study of the effect of pulse coolant flow on thermal and hydrodynamic processes, have yielded a combination of factors reflecting technical and economic rationality of application of pulse coolant circulation. 

  8. Regional Energy Planning Tool for Renewable Integrated Low-Energy District Heating Systems

    DEFF Research Database (Denmark)

    Tol, Hakan; Dincer, Ibrahim; Svendsen, Svend

    2013-01-01

    Low-energy district heating systems, operating at low temperature of 55 °C as supply and 25°C as return, can be the energy solution as being the prevailing heating infrastructure in urban areas, considering future energy schemesaiming at increased exploitation of renewable energy sources together...... with low-energy houses in focus with intensified energy efficiency measures. Employing low-temperature operation allows the ease to exploit not only any type of heat source but also low-grade sources, i.e., renewable and industrial waste heat, which would otherwise be lost. In this chapter, a regional...... energy planning tool is described considered with various energy conversion systems based on renewable energy sources to be supplied to an integrated energy infrastructure involving a low-energy district heating, a district cooling, and an electricity grid. The developed tool is performed for two case...

  9. Shortage of energy increases profitability of district heating; Energiknapphet gjoer fjernvarme mer loennsomt

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    Increased demand will cause the price of district heating to increase, but not to the level of the price of electricity. The cheapest heating alternative in Denmark, Norway and Sweden is district heating. In Norway, district heating is developed primarily for commercial buildings and housing cooperatives. Thirty per cent of all buildings under construction are prepared for district heating and the percentage will increase strongly in the coming time. The total net production of district heating in Norway in 2001 was 2000 GWh, which is only a small part of the total potential for district heating.

  10. Analysis of the Impact of Decreasing District Heating Supply Temperature on Combined Heat and Power Plant Operation

    OpenAIRE

    Bolonina Alona; Bolonins Genadijs; Blumberga Dagnija

    2014-01-01

    District heating systems are widely used to supply heat to different groups of heat consumers. The district heating system offers great opportunities for combined heat and power production. In this paper decreasing district heating supply temperature is analysed in the context of combined heat and power plant operation. A mathematical model of a CHP plant is developed using both empirical and theoretical equations. The model is used for analysis of modified CHP plant operation modes with redu...

  11. Margins in Swedish district heating systems; Marginaler i Fjaerrvaermesystem

    Energy Technology Data Exchange (ETDEWEB)

    Selinder, Patrik; Zinko, Heimo [ZW Energiteknik AB, Nykoeping (Sweden)

    2003-03-01

    occasions with power deficiency will occur more often. The lower limit for the reduction of connection power is depending on the level of comfort the customers are prepared to accept. These questions have been discussed with selected customer representatives. The mentioned practice of oversizing of the heating power deliverable to the buildings presents a relatively large margin for reduction of consumable power without decreasing the level of heating comfort too much. In the report this method is recommended under the name 'stingy' (= adequate) dimensioning; it is still according to the recommendation of the Swedish building code based on DUT20 and following the regulations of the Swedish District Heating Association for the domestic hot water dimensioning. The result will be a decrease of about 30% of the connected power in most buildings, and somewhat more in the heaviest buildings. Further reduction of the connecting power will implicate a more strong impact on the heating comfort. We call this 'deficiency dimensioning' and we cannot really recommend it apart from some special customer groups who might accept this heating quality by receiving some kind of economic compensation.

  12. Optimal phasing of district heating network investments using multi-stage stochastic programming

    Directory of Open Access Journals (Sweden)

    Romain Stephane Claude Lambert

    2016-06-01

    Full Text Available Most design optimisation studies for district heating systems have focused on the optimal sizing of network assets and on the location of production units. However, the strategic value of the flexibility in phasing of the inherently modular heat networks, which is an important aspect in many feasibility studies for district heating schemes in the UK, is almost always neglected in the scientific literature. This paper considers the sequential problem faced by a decision-maker in the phasing of long-term investments into district heating networks and their expansions. The problem is formulated as a multi-stage stochastic programme to determine the annual capital expenditure that maximises the expected net present value of the project. The optimisation approach is illustrated by applying it to the hypothetical case of the UK’s Marston Vale eco town. It was found that the approach is capable of simulating the optimal growth of a network, from both a single heat source or separate islands of growth, as well as the optimal marginal expansion of an existing district heating network. The proposed approach can be used by decision makers as a framework to determine both the optimal phasing and extension of district heating networks and can be adapted simply to various, more complex real-life situations by introducing additional constraints and parameters. The versatility of the base formulation also makes it a powerful approach regardless of the size of the network and also potentially applicable to cooling networks.

  13. Exergetic evaluation of heat pump booster configurations in a low temperature district heating network

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Elmegaard, Brian

    2012-01-01

    In order to minimise losses in a district heating network, one approach is to lower the temperature difference between working media and soil. Considering only direct heat exchange, the minimum forward temperature level is determined by the demand side, as energy services are required at a certain...... temperature. As domestic hot water is required at a temperature range where legionella is no longer a threat, forward temperatures in a traditional low temperature district heating network cannot be lowered beyond approximately 55 ºC. One solution is to boost the temperature of the forward tap water stream...... with a heat pump, as the remaining heat demands are often not required at temperature levels as high as the tap water. The scope of this work is to evaluate the power consumption and second law efficiency of booster heat pumps for tap water production in a low temperature district heating network. The heat...

  14. Co-sponsored second quarter progress review conference on district heating

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-01-01

    A summary of the progress review conference on district heating and cooling systems is presented. The agenda and lists of speakers and attendees are presented. A history of district heating and some present needs and future policies are given and an excerpt from the National District Heating Program Strategy (DOE, March 1980) is included. Following the presentation, District Heating and Cooling Systems Program, by Alan M. Rubin, a fact sheet on DOE's Integrated Community Energy Systems Program and information from an oral presentation, District Heating and Cooling Systems for Communities Through Power Plant Retrofit Distribution Network, are given. The Second Quarterly Oral Report to the US DOE on the District Heating and Cooling Project in Detroit; the executive summary of the Piqua, Ohio District Heating and Cooling Demonstration Project; the Second Quarterly Report of the Moorehead, Minnesota District Heating Project; and the report from the Moorehead, Minnesota mayor on the Hot Water District Heating Project are presented.

  15. Integration of space heating and hot water supply in low temperature district heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2016-01-01

    electric heating and three heat pump solutions applying R134a and R744. The results show that conventional solutions at lowest possible temperature have the highest exergetic efficiency of 28% and lowest annual cost of € 690 for a 159 m2 house. The best low temperature system is an R134a heat pump with hot......District heating may supply many consumers efficiently, but the heat loss from the pipes to the ground is a challenge. The heat loss may be lowered by decreasing the network temperatures for which reason low temperature networks are proposed for future district heating. The heating demand...... of the consumers involves both domestic hot water and space heating. Space heating may be provided at low temperature in low energy buildings. Domestic hot water, however, needs sufficient temperatures to avoid growth of legionella. If the network temperature is below the demand temperature, supplementary heating...

  16. Thermoeconomic Diagnosis of anUrban District Heating System based onCogenerative Steam and Gas Turbines

    OpenAIRE

    Verda, Vittorio

    2001-01-01

    The energy system diagnosis is a experimental technique applied for the detection and the location of possible anomalies. These information are obtained by comparing the values assumed by opportune variables in a operation condition with the corresponding reference values. In this thesis a procedure based on the use of thermodynamic variables, elaborated using the thermoeconomic methods, is proposed. The main originality, in comparison with other thermoeconomic diagnosis procedures, consists ...

  17. Solar energy for district heating and group centers

    Energy Technology Data Exchange (ETDEWEB)

    Wahlman, E.; Zinko, H.; Hultmark, G.; Isakson, P.; Karlsson, B.; Margen, P.

    1984-01-01

    The report presents the technique and the state of the art concerning solar energy in a district heating system by the turn of the year 1983/84. The market potential and the cost accounting and the development are discussed. An estimate of the energy production of solar collector systems is presented. 11 different pilot and demonstration plants for solar district heating are described, particularly the plants at Tumba, Knivsta, Studsvik, Torvalla, Ingelstad and Lyckebo. The experience and the general trend is expressed as a change towards large units and a reduction of cost. Continued research and development is recommended.

  18. Load Management in District Heating Operation

    DEFF Research Database (Denmark)

    Li, Hongwei; Wang, Stephen Jia

    2015-01-01

    heating load can be reduced through building demand side management. The building thermal mass can be used to shift the heating supply under the circumstance without jeopardizing the consumer thermal comfort. In this paper, the multi-agent framework is applied to a simplified building dynamic model...

  19. 1992 National census for district heating, cooling and cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-01

    District energy systems are a major part of the energy use and delivery infrastructure of the United States. With nearly 6,000 operating systems currently in place, district energy represents approximately 800 billion BTU per hour of installed thermal production capacity, and provides over 1.1 quadrillion BTU of energy annually -- about 1.3% of all energy used in the US each year. Delivered through more that 20,000 miles of pipe, this energy is used to heat and cool almost 12 billion square feet of enclosed space in buildings that serve a diverse range of office, education, health care, military, industrial and residential needs. This Census is intended to provide a better understanding of the character and extent of district heating, cooling and cogeneration in the United States. It defines a district energy system as: Any system that provides thermal energy (steam, hot water, or chilled water) for space heating, space cooling, or process uses from a central plant, and that distributes the energy to two or more buildings through a network of pipes. If electricity is produced, the system is a cogenerating facility. The Census was conducted through surveys administered to the memberships of eleven national associations and agencies that collectively represent the great majority of the nation`s district energy system operators. Responses received from these surveys account for about 11% of all district systems in the United States. Data in this report is organized and presented within six user sectors selected to illustrate the significance of district energy in institutional, community and utility settings. Projections estimate the full extent of district energy systems in each sector.

  20. A modeling approach for district heating systems with focus on transient heat transfer in pipe networks

    DEFF Research Database (Denmark)

    Mohammadi, Soma; Bojesen, Carsten

    2015-01-01

    Increasing the building energy efficiency in recent years results in noticeably reduction in their heating demand. Combined with the current trend for utilizing low temperature heat sources, it raises the necessity of introducing a new generation of district heating [DH] systems with lowered...

  1. Quantitative thermography and methods for in-situ determination of heat losses from district heating networks

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, B. [ed.

    1996-11-01

    The course and seminar summarizing application of infrared thermography in district heating systems control gathered Danish specialists with 5 contributions on the subject. Maintenance of the heat distribution pipelines and thermographic inspection of the systems are essential in order to avoid heat losses. (EG)

  2. Heat planning for fossil-fuel-free district heating areas with extensive end-use heat savings

    DEFF Research Database (Denmark)

    Harrestrup, Maria; Svendsen, S.

    2014-01-01

    is a theoretical investigation of the district heating system in the Copenhagen area, in which heat conservation is related to the heat supply in buildings from an economic perspective. Supplying the existing building stock from low-temperature energy resources, e.g. geothermal heat, might lead to oversized...

  3. Shallow burial of district heating pipes; Grund foerlaeggning av fjaerrvaermeledningar

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Stefan; Saellberg, Sven-Erik; Bergstroem, Gunnar [Swedish National Testing and Research Inst., Boraas (Sweden)

    2006-07-28

    Previous studies have shown that the investment costs for district heating installations in suburban areas can be lowered with more rational construction work. This project has studied the possibilities of decreasing the laying depth for pipes in residential-area roads without risking damage on neither pipe nor road surface. An inventory of regulations from national and local authorities and district heating companies in Sweden was done. The larger cities have specific requirements regarding laying depth in road structures. In most places, however, the guidelines issued by the Swedish District Heating Association are followed. And in smaller cities, the question is handled directly by the municipal district heating company. In some places, e.g., Goeteborg, Joenkoeping and Luleaa, the local authorities and the district heating company have agreed on a smaller laying depth under certain circumstances. An analysis of the costs related to the excavation work, backfilling and asphalt laying showed that the costs can be reduced with about 30 % by decreasing the laying depth from 600 mm to 350 mm. A field trial was done with four twin pipes of dimension 2 x DN 32/160 laid 600 mm, 380 mm, 280 mm and 180 mm below the asphalt surface in a road with heavy traffic. Apart from the laying depth, the installation work was done in accordance with the guidelines from the Swedish District Heating Association. During traffic loading, measurements of internal deformations of the pipes, wheel-track depths in the asphalt surface and load-bearing capacity of the road structure were made. The deformation of the pipes is negligible at all laying depths. This is likely due to an arching action from the backfill which supports most of the forces from the traffic load. Significant wheel-tracks were measured, but they seem to correspond directly to settlements in the new soil. Hence, a shallower pipe trench leads to less prominent wheel-tracks. Shallow pipe burial yields slightly larger heat

  4. Analysis of the Impact of Decreasing District Heating Supply Temperature on Combined Heat and Power Plant Operation

    Directory of Open Access Journals (Sweden)

    Bolonina Alona

    2014-12-01

    Full Text Available District heating systems are widely used to supply heat to different groups of heat consumers. The district heating system offers great opportunities for combined heat and power production. In this paper decreasing district heating supply temperature is analysed in the context of combined heat and power plant operation. A mathematical model of a CHP plant is developed using both empirical and theoretical equations. The model is used for analysis of modified CHP plant operation modes with reduced district heating supply temperature. Conclusions on the benefits of new operation modes are introduced.

  5. Integration of Decentralized Thermal Storages Within District Heating (DH Networks

    Directory of Open Access Journals (Sweden)

    Schuchardt Georg K.

    2016-12-01

    Full Text Available Thermal Storages and Thermal Accumulators are an important component within District Heating (DH systems, adding flexibility and offering additional business opportunities for these systems. Furthermore, these components have a major impact on the energy and exergy efficiency as well as the heat losses of the heat distribution system. Especially the integration of Thermal Storages within ill-conditioned parts of the overall DH system enhances the efficiency of the heat distribution. Regarding an illustrative and simplified example for a DH system, the interactions of different heat storage concepts (centralized and decentralized and the heat losses, energy and exergy efficiencies will be examined by considering the thermal state of the heat distribution network.

  6. Ground Source Geothermal District Heating and Cooling System

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, James William [Ball State Univ., Muncie, IN (United States)

    2016-10-21

    Ball State University converted its campus from a coal-fired steam boiler district heating system to a ground source heat pump geothermal district system that produces simultaneously hot water for heating and chilled water for cooling. This system will include the installation of 3,600 four hundred feet deep vertical closed loop boreholes making it the largest ground source geothermal district system in the country. The boreholes will act as heat exchangers and transfer heat by virtue of the earth’s ability to maintain an average temperature of 55 degree Fahrenheit. With growing international concern for global warming and the need to reduce worldwide carbon dioxide loading of the atmosphere geothermal is poised to provide the means to help reduce carbon dioxide emissions. The shift from burning coal to utilizing ground source geothermal will increase electrical consumption but an overall decrease in energy use and reduction in carbon dioxide output will be achieved. This achievement is a result of coupling the ground source geothermal boreholes with large heat pump chiller technology. The system provides the thermodynamic means to move large amounts of energy with limited energy input. Ball State University: http://cms.bsu.edu/About/Geothermal.aspx

  7. A new district heating system in the city of Bolanzo

    DEFF Research Database (Denmark)

    Mazzocato, Alessandro; Li, Hongwei; Marchiori, S.

    2014-01-01

    In the context of the EU project “Sinfonia”, that aims to reduce Bolzano’s primary energy consumption up to 40%, SEL AG, an Italian energy company is planning to extend the existing district heating and cooling (DHC) network and explore strategies to improve efficiency, environmental, and economi...

  8. Benefits of Integrating Geographically Distributed District Heating Systems

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo; Bačeković, I.; Sveinbjörnsson, Dadi Þorsteinn

    2016-01-01

    Although liberalization of the electricity day-ahead markets has gained pace throughout the Europe, district heating markets are often dominated by lack of competition between suppliers, which curbs the potential of having cheaper systems in terms of socio-economic costs, and technically better s...

  9. Comparison of corrosion monitoring techniques in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Nielsen, Lars Vendelbo; Thorarinsdottir, R.I.

    2004-01-01

    Investigations aimed at evaluating monitoring techniques as a function of the specific water chemistry has been conducted as a part of a Nordic project focused on improving the quality of corrosion monitoring in municipal district heating. A combination of techniques has been selected to measure...

  10. Cooperation in district heating networks in the Netherlands

    NARCIS (Netherlands)

    Ligtvoet, A.

    2012-01-01

    Although constructing a district heating network could be portrayed as a simple cost/benefit calculation, we suggest that other factors play an important role that cannot be ignored. In this contribution, we suggest that theories concerning cooperation (in industrial networks) roughly apply to micro

  11. A control model for district heating networks with storage

    NARCIS (Netherlands)

    Scholten, Tjeert; De Persis, Claudio; Tesi, Pietro

    2014-01-01

    In [1] pressure control of hydraulic networks is investigated. We extend this work to district heating systems with storage capabilities and derive a model taking the topology of the network into account. The goal for the derived model is that it should allow for control of the storage level and tem

  12. Plug and Play Process Control of a District Heating System

    DEFF Research Database (Denmark)

    Trangbaek, Klaus; Knudsen, Torben; Skovmose Kallesøe, Carsten

    2009-01-01

    The main idea of plug and play process control is to initialise and reconfigure control systems automatically. In this paper these ideas are applied to a scaled laboratory model of a district heating pressure control system.  First of all this serves as a concrete example of plug and play control...

  13. Magneto-Inductive Underground Communications in a District Heating System

    DEFF Research Database (Denmark)

    Meybodi, Soroush Afkhami; Nielsen, Jens Frederik Dalsgaard; Bendtsen, Jan Dimon

    2011-01-01

    Feasibility of underground data communications is investigated by employing magnetic induction as the key technology at physical layer. Realizing an underground wireless sensor network for a district heating plant motivates this research problem. The main contribution of the paper is to find...

  14. Cooperation in district heating networks in the Netherlands

    NARCIS (Netherlands)

    Ligtvoet, A.

    2012-01-01

    Although constructing a district heating network could be portrayed as a simple cost/benefit calculation, we suggest that other factors play an important role that cannot be ignored. In this contribution, we suggest that theories concerning cooperation (in industrial networks) roughly apply to micro

  15. A control model for district heating networks with storage

    NARCIS (Netherlands)

    Scholten, Tjeert; De Persis, Claudio; Tesi, Pietro

    2014-01-01

    In [1] pressure control of hydraulic networks is investigated. We extend this work to district heating systems with storage capabilities and derive a model taking the topology of the network into account. The goal for the derived model is that it should allow for control of the storage level and tem

  16. On-line Corrosion Monitoring in District Heating Systems

    DEFF Research Database (Denmark)

    Richter, Sonja; Thorarinsdottir, R.I.; Hilbert, Lisbeth Rischel

    2005-01-01

    The corrosion control in district heating systems is today performed primarily with control of the water quality. The corrosion rate is kept low by assuring low dissolved oxygen concentration, high pH and low conductivity. Corrosion failures can occur, e.g. as a result of unknown oxygen ingress...

  17. Online, real-time corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.

    2005-01-01

    The corrosion control in district heating systems is today performed primarily with control of the water quality. The corrosion rate is kept low by assuring low dissolved oxygen concentration, high pH and low conductivity. Corrosion failures can occur, e.g. as a result of unknown oxygen ingress...

  18. Feasibility study for retrofitting biogas cogeneration systems to district heating in South Korea.

    Science.gov (United States)

    Chung, Mo; Park, Hwa-Choon

    2015-08-01

    A feasibility study was performed to assess the technical and economic merits of retrofitting biogas-based cogeneration systems to district heating networks. Three district heating plants were selected as candidates for accommodating heat recovery from nearby waste treatment stations, where a massive amount of biogas can be produced on a regular basis. The scenario involves constructing cogeneration systems in each waste treatment station and producing electricity and heat. The amounts of biogas production for each station are estimated based on the monthly treatment capacities surveyed over the most recent years. Heat produced by the cogeneration system is first consumed on site by the waste treatment system to keep the operating temperature at a proper level. If surplus heat is available, it will be transported to the nearest district heating plant. The year-round operation of the cogeneration system was simulated to estimate the electricity and heat production. We considered cost associated with the installation of the cogeneration system and piping as initial investments. Profits from selling electricity and recovering heat are counted as income, while costs associated with buying biogas are expenses. Simple payback periods of 2-10 years were projected under the current economic conditions of South Korea. We found that most of the proposed scenarios can contribute to both energy savings and environmental protection.

  19. Make the heat hotter. - marketing district heating to households in detached houses

    Energy Technology Data Exchange (ETDEWEB)

    Sernhed, Kerstin; Pyrko, Jurek

    2008-09-15

    For district heating (DH) companies, to expand in low heat density areas such as detached houses, it is essential to obtain a high rate of connections to the district-heating network in order to enhance the cost effectiveness. Marketing district heating to house owners is, however, a fairly different matter from selling it to customers in industrial, commercial, and multi-family buildings. Suitable market strategies need to be developed and the need for information about potential customers' preferences and attitudes are of great importance since the house-owners often constitute a heterogeneous group where different households have different requirements. This paper investigates a case of one Swedish district heating company's marketing activities and expansion strategies in a single family house area where the customers were offered conversion of their direct resistive electric heating (DEH) into district heating (DH). 88 out of 111 houses were converted in 2002. Four years later, interviews were carried out with 23 of the households in the area, both with those who had accept-ed the district heating offer and those who had not. The study shows that apart from the economic aspects, thermal comfort, aesthetics and practicalities also affected the buying decision. Since the different economic aspects of the offer were complex, it was very difficult for the households to make a strictly rational economical decision. Statistical analysis confirmed that variables such as age, type of household and energy use level could, to some extent, be related to the decision to convert from electric heating to district heating. Timing, low prices and the total solutions presented to the households were crucial factors in the success of the marketing strategy.

  20. Regulating the price of district heating; Regulering av prisen paa fjernvarme

    Energy Technology Data Exchange (ETDEWEB)

    2010-03-15

    The price of district heating for clients in facilities subject to attachment duty, is currently regulated by the Energy Act 5-5, which says that the price of heating shall not exceed the price of electric heating in the area. The current practice of 5-5 can be improved by using a) the actual time profiles of the consumption of heat and area power prices in Nord Pool's spot market, b) actual net tariffs, energy and potential power per customer, and c) the total charges on the end use of electricity, including the funding of support schemes for renewable energy. This provides a model that is more in line with the prices customers actually pay and maintains respect for the district heating companies' finances, while it is practically manageable. On the other hand, provides an electricity price-based regulation not the right signals about the social economic value of district heating. This is because the net charges do not reflect the social-economic costs in the electricity grid through increased use of electricity for heating and that the end user fees are a poor measure of the environmental costs of production and transmission. There is a risk that the most profitable community heating projects economically is not realized, which is in violation of the energy Act. Maximum price controls alone can not be used to achieve the goal of social economic profitable development of district heating and district heating companies' finances at the same time, but requires additional measures. (AG)

  1. The economic framework of the heat market - price formation for district heating; Der wirtschaftliche Rahmen des Waermemarktes - Preisbildung fuer Fernwaerme

    Energy Technology Data Exchange (ETDEWEB)

    Wittkamp, H. [Hamburgische Electricitaets-Werke AG, Hamburg (Germany)]|[Arbeitsgemeinschaft Fernwaerme e.V., Frankfurt am Main (Germany)

    1994-12-31

    The formation of prices for district heat supply concerns is largely determined by the costs for the provision and delivery of district heating and the acceptability of the prices in the local heat market. The classical formula for calculations is `costs+profit=price`. If the calculated district heat price exceeds the acceptable level, there is a danger that district heating will be displaced from the market by the competing heat on offer, based on natural gas or heating oil. An instrument for coping with this situation could be by target cost calculation. In this process, a market-orientated cost management is built up, with the aid of which, the costs for the generation and distribution of district heating are dimensioned suitable for sale and management. The formula for calculation here is `Market price (fixed parameters)/Target profit=Target costs`. (orig.) [Deutsch] Die Preisbildung der Fernwaermeversorgungsunternehmen (FVU) wird im wesentlichen durch Kosten fuer die Bereitstellung und Lieferung von Fernwaerme sowie die Anlegbarkeit (Akzeptanz) der Preise auf dem oertlichen Waermemarkt bestimmt. Die klassische Kalkulationsformel lautet `Kosten+Gewinn=Preis`. Uebersteigt der kalkulierte Fernwaermepreis das anlegbare Niveau, besteht die Gefahr, dass die Fernwaerme von den konkurrierenden Waermedarbietungen auf der Basis von Erdgas oder Heizoel aus dem Markt gedraengt wird. Ein Instrument, dieser Situation gerecht zu werden, koennte die Zielkostenrechnung sein. Bei diesem Verfahren wird ein marktorientiertes Kostenmanagement aufgebaut, mit dessen Hilfe die Kosten fuer die Erzeugung und Verteilung von Fernwaerme, den Vertrieb und die Verwaltung angemessen dimensioniert werden. Die Kalkulationsformel lautet hier `Marktpreis (feste Groesse)/Zielgewinn=Zielkosten. (orig.)

  2. District heating : 50 years of experience in Linkoping

    Energy Technology Data Exchange (ETDEWEB)

    Ohlander, P.; Fahlstrom [Tekniska Verken (Sweden)

    2005-07-01

    Some facts about the municipality of Linkoping, Sweden were presented along with an action plan adopted by the Municipal Council in 1998 for sustainable development. Tekniska Verken in Linkoping offers electricity and power grid management; potable water and sewage management; recycling and waste to energy for district heating and cooling; biogas production from biological waste; and, communication technology and leading edge solutions for installing the required infrastructure for all grids. The installation of the first district heating pipelines took place in Linkoping in 1954 and the first waste to energy plant in Sweden was operational by 1958. A combined heat and power plant was commissioned in 1964 with a capacity of 280 MW and with an electricity output of 96 MW{sub e}. A medium sized waste to energy plant was commissioned in 1982 in which municipal waste was thermally treated for the production of district energy. In 2005, the Garstad Waste to Energy Plant was expanded to become one of the most sophisticated plants in the world, working in a combined cycle. It is used for the thermal treatment of municipal waste with a capacity of more than 350,000 metric tons. It is utilized for districting heating, district cooling and electricity generation. This presentation showed how the Tekniska Verken Group has responded to the growing need for district heating and the trend to reduce the use of fossil fuels by focusing its efforts on refining waste to energy techniques and by developing new areas for energy use, such as district cooling. The Tekniska Verken Group has also produced methane from biological waste. A schematic of the new combined heat and power (CHP) plant at Garstad was presented along with graphs of fuel mix, energy output and emissions. This presentation also discussed the development of the waste to biogas concept with reference to the production method of anaerobic digestion of sewage sludge at waste water treatment plants. The many advantages of

  3. Heat Driven Cooling in District Energy Systems; Vaermedriven Kyla

    Energy Technology Data Exchange (ETDEWEB)

    Rydstrand, Magnus; Martin, Viktoria; Westermark, Mats [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    2004-07-01

    This report is reviewing different heat driven technologies for the production of cooling. It is shown that the supply of cooling gives the highest fuel utilization if heat from CHP production is used for the production of cooling instead of maximizing the electricity output in a condensing plant. High fuel utilization is reached since the direct production of cooling from heat is a thermodynamic shortcut as compared to the production of electricity as an intermediate product before cooling is produced. At direct production of cooling from heat it is possible to obtain 70 percent of the obtainable cooling of an ideal process. If electricity is produced from heat, 70 percent electricity could be obtained as compared to an ideal process. If this electricity would be used for the production of cooling 70 percent of the obtainable cooling in an ideal process would the result. The total production of cooling from heat with electricity as an intermediate product would therefore give 50 percent cooling as compared to an ideal process. Hence, heat driven cooling will give more cooling for a given fuel input. In the review of the different heat driven cooling options it was found that there are many alternatives suitable for different applications. Absorption cooling is suitable for water distributed cooling if the latent cooling load is low. Desiccant cooling is believed to have a large market in climates (applications) with high latent cooling loads. In the energy efficiency evaluation it is found that the highest fuel utilization is given for a central production of electricity using either district heating or district cooling as the energy carrier to supply cooling. In fact the potential of district heating as the energy carrier is thought to be the largest in large cities with humid climates. Further it is found that the chiller heat sink can contribute significantly to the cost in many applications, especially if water and/or electricity consumption are issues with

  4. Optimal Operation System of the Integrated District Heating System with Multiple Regional Branches

    Science.gov (United States)

    Kim, Ui Sik; Park, Tae Chang; Kim, Lae-Hyun; Yeo, Yeong Koo

    This paper presents an optimal production and distribution management for structural and operational optimization of the integrated district heating system (DHS) with multiple regional branches. A DHS consists of energy suppliers and consumers, district heating pipelines network and heat storage facilities in the covered region. In the optimal management system, production of heat and electric power, regional heat demand, electric power bidding and sales, transport and storage of heat at each regional DHS are taken into account. The optimal management system is formulated as a mixed integer linear programming (MILP) where the objectives is to minimize the overall cost of the integrated DHS while satisfying the operation constraints of heat units and networks as well as fulfilling heating demands from consumers. Piecewise linear formulation of the production cost function and stairwise formulation of the start-up cost function are used to compute nonlinear cost function approximately. Evaluation of the total overall cost is based on weekly operations at each district heat branches. Numerical simulations show the increase of energy efficiency due to the introduction of the present optimal management system.

  5. Returns and solvency in the Norwegian district heating sector 2010; Avkastning og soliditet i fjernvarmebransjen 2010

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    On behalf of Enova Pareto conducted an analysis of returns and solvency in the district heating sector for fiscal years 2009 and 2010. The analysis focuses on a representative sample of the largest district heating companies in Norway. A total of 26 companies have been analyzed. These companies provide a total of ~ 80% of the district heating in Norway. (eb)

  6. Istra district heating system. Master plan and feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-01

    This report presents the results of the Feasibility Study of options for improving the efficiency and operating economy of Istra Large-Scale Demonstration Project includes all areas of the town of Istra. However, the Feasibility Study is confined to the five largest adjoining boilers plant areas within the borders of Istra town. The study was conducted from 1999 to 2001 and was based on information collected during this period. The city administration and the district heating company in Istra provided the data. The company RDIEE, Russian Danish Institute for Energy Efficiency, in Istra collected and processed the data under the conduction of Carl Bro a/s in Denmark. The main objectives of the study are to provide the Istra DHC with a number of options for future development of the district heating system based on technical/financial analyses and presenting the best possibilities for improved comfort, operation and business development. More concretely, one or more system improvement scenarios, which can be implemented in the near future as a first step of the recommended medium-term to long-term development, are identified. Another important objective has been to train the specialists of RDIEE in the feasibility study process and to transfer know-how, skills and tools. The model used for this study is adapted to the features and the special problems to be addressed in relation to the Istra district heating system. RDIEE and Istra DHC are thereby provided with a useful tool which may be used for continued study and development after the first phase project has been completed. As usual in the case of input/output models the quality of the results depends very much on the quality of input data. The present report is exclusively based on the consultant's understanding of the provided information. The results and the underlying inputs should be carefully considered before any final decision concerning implementation is taken. Verification of assumptions should also

  7. Large scale solar district heating. Evaluation, modelling and designing

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.

    2000-07-01

    The main objective of the research was to evaluate large-scale solar heating connected to district heating (CSDHP), to build up a simulation tool and to demonstrate the application of the tool for design studies and on a local energy planning case. The evaluation of the central solar heating technology is based on measurements on the case plant in Marstal, Denmark, and on published and unpublished data for other, mainly Danish, CSDHP plants. Evaluations on the thermal, economical and environmental performances are reported, based on the experiences from the last decade. The measurements from the Marstal case are analysed, experiences extracted and minor improvements to the plant design proposed. For the detailed designing and energy planning of CSDHPs, a computer simulation model is developed and validated on the measurements from the Marstal case. The final model is then generalised to a 'generic' model for CSDHPs in general. The meteorological reference data, Danish Reference Year, is applied to find the mean performance for the plant designs. To find the expectable variety of the thermal performance of such plants, a method is proposed where data from a year with poor solar irradiation and a year with strong solar irradiation are applied. Equipped with a simulation tool design studies are carried out spreading from parameter analysis over energy planning for a new settlement to a proposal for the combination of plane solar collectors with high performance solar collectors, exemplified by a trough solar collector. The methodology of utilising computer simulation proved to be a cheap and relevant tool in the design of future solar heating plants. The thesis also exposed the demand for developing computer models for the more advanced solar collector designs and especially for the control operation of CSHPs. In the final chapter the CSHP technology is put into perspective with respect to other possible technologies to find the relevance of the application

  8. Casing of preinsulated district heating pipes. Functional Requirements. Scientific report

    Energy Technology Data Exchange (ETDEWEB)

    Bryder, K.L.; Feld, T.; Randloev, P.; Vestergaard, J.B.; Noergaard Pedersen, H.; Palle, S.; Amby, L.

    1996-10-01

    Requirements for the wall thickness of the casing pipes in Europe were formulated to clarify the laying conditions, representative for the European district heating areas. We achieved a broad estimate by defining four scenarios for the laying of district heating pipes. It is common to the four scenarios that that all bends, branches etc. are always laid in sand. The four scenarios are differentiated by soil types. The soil types include: Uniform sand, Well graded gravel, Sand with fines and Sand with crushed stone. In the following analysis it was possible to examine the influence from following parameters: Casing thickness; Diameter of steel pipe; Diameter of casing; Material properties (PUR and PE); Soil type. The results from the model showed that uniform sand is the absolute best soil type. Based on the results from and earlier project a laboratory method has been developed. The result was a test method based on the indentation of three mandrels with a diameter of {phi}30 mm with a taper with an angle of 45 deg. and with roundings on the apex of R5 mm, R10 mm and R15 mm, respectively. The mandrels simulate stones. The examinations among other things showed that even a 1.5 mm casing demands an indentation of 20 mm with a R5 mm mandrel before it is perforated. The demanded force is 1.6 kN, which is considerably higher than the theoretically highest force in an actual situation. On this background it is recommended that the minimum requirement for the wall thickness of the casings with diameters less than 200 mm should still follow the EN 253, whereas the minimum requirement for the larger casing pipes securely can be reduced. Based on the tests and an evaluation of the safety factors it is proposed that the wall thickness for the largest pipes can be reduced 50%. Thus the wall thickness of an 800 mm casing should be 6.6 mm with a linear reduction down to 3 mm for 180 mm casing. (EG)

  9. Energy Savings Potential for Pumping Water in District Heating Stations

    Directory of Open Access Journals (Sweden)

    Ioan Sarbu

    2015-05-01

    Full Text Available In district heating stations, the heat carrier is circulated between the energy source and consumers by a pumping system. Fluid handling systems, such as pumping systems, are responsible for a significant portion of the total electrical energy use. Significant opportunities exist to reduce pumping energy through smart design, retrofitting, and operating practices. Most existing systems requiring flow control make use of bypass lines, throttling valves or pump speed adjustments. The most efficient of these options is pump speed control. One of the issues in using variable-speed pumping systems, however, is the total efficiency of the electric motor/pump arrangement under a given operating condition. This paper provides a comprehensive discussion about pump control in heating stations and analyzes the energy efficiency of flow control methods. Specific attention is also given to the selection of motor types, sizing and pump duty cycle. A comparative energy analysis is performed on the hot water discharge adjustment using throttling control valves and variable-speed drives in a district heating station constructed in Romania. To correlate the pumped flow rate with the heat demand and to ensure the necessary pressure using minimum energy, an automatic system has been designed. The performances of these control methods are evaluated in two practical applications. The results show that approximately 20%–50% of total pumping energy could be saved by using the optimal control method with variable-speed pumps. Additionally, some modernization solutions to reduce the environmental impact of heating stations are described.

  10. On-line corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Richter, Sonja; Thorarinsdottir, R.I.; Hilbert, Lisbeth Rischel

    2004-01-01

    Traditionally corrosion monitoring in district heating systems has been performed offline via weight loss coupons. These measurements give information about the past and not the present situation and require long exposure time (weeks or months). The good quality of district heating medium makes...... corrosion monitoring a challenge. Under normal conditions the pH is high (app. 9), conductivity is low (app. 10-200 µS/cm) and the concentration of dissolved oxygen is negligible. The low corrosion rates (in the order of µm/y) are difficult to measure and furthermore, factors such as hydrogen sulphide......), Electrochemical Noise (EN) and Zero Resistance Ammetry (ZRA). Electrochemical Resistance (ER) has also been used to measure corrosion. The method traditionally only measures corrosion off-line but with newly developed high-sensitive ER technique developed by MetriCorr in Denmark, on-line monitoring is possible...

  11. On-line corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Richter, Sonja; Thorarinsdottir, R.I.; Hilbert, Lisbeth Rischel

    2004-01-01

    complicates the chemistry of the environment. Hydrogen sulphide is present in geothermal systems and can be formed as a by-product of sulphate-reducing-bacteria (SRB). The application of electrochemical methods makes on-line monitoring possible. These methods include: Linear Polarization Resistance (LPR......), Electrochemical Noise (EN) and Zero Resistance Ammetry (ZRA). Electrochemical Resistance (ER) has also been used to measure corrosion. The method traditionally only measures corrosion off-line but with newly developed high-sensitive ER technique developed by MetriCorr in Denmark, on-line monitoring is possible......Traditionally corrosion monitoring in district heating systems has been performed offline via weight loss coupons. These measurements give information about the past and not the present situation and require long exposure time (weeks or months). The good quality of district heating medium makes...

  12. On-line Corrosion Monitoring in District Heating Systems

    DEFF Research Database (Denmark)

    Richter, Sonja; Thorarinsdottir, R.I.; Hilbert, Lisbeth Rischel

    2005-01-01

    The corrosion control in district heating systems is today performed primarily with control of the water quality. The corrosion rate is kept low by assuring low dissolved oxygen concentration, high pH and low conductivity. Corrosion failures can occur, e.g. as a result of unknown oxygen ingress......, precipitation of deposits or crevices. The authors describe methods used for on-line monitoring of corrosion, cover the complications and the main results of a Nordic project....

  13. Online, real-time corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.

    2005-01-01

    The corrosion control in district heating systems is today performed primarily with control of the water quality. The corrosion rate is kept low by assuring low dissolved oxygen concentration, high pH and low conductivity. Corrosion failures can occur, e.g. as a result of unknown oxygen ingress......, precipitation of deposits or crevices. The authors describe methods used for on-line monitoring of corrosion, cover the complications and the main results of a Nordic project....

  14. Magneto-Inductive Underground Communications in a District Heating System

    DEFF Research Database (Denmark)

    Meybodi, Soroush Afkhami; Nielsen, Jens Frederik Dalsgaard; Bendtsen, Jan Dimon

    2011-01-01

    Feasibility of underground data communications is investigated by employing magnetic induction as the key technology at physical layer. Realizing an underground wireless sensor network for a district heating plant motivates this research problem. The main contribution of the paper is to find the ...... the optimal design for transmitter and receiver coil antennas, assuming predefined wire gauge and length at both sides. Analytical results show that the transmitter coil should have the smallest possible radius while the converse is true for the receiver coil....

  15. The Convenience Benefits of the District Heating System over Individual Heating Systems in Korean Households

    Directory of Open Access Journals (Sweden)

    Hyo-Jin Kim

    2017-08-01

    Full Text Available Koreans usually prefer the district heating system (DHS to the individual heating system (IHS because DHS can give them convenience and safety within their living environment. The Korean government thus plans to expand the DHS and requires information about the value that consumers place on the DHS over the IHS, which has not been dealt with in academic literature. This paper attempts to investigate Korean households’ willingness to pay (WTP for DHS over IHS, for residential heat (RH. To this end, the authors apply the dichotomous choice contingent valuation to assessing additional WTP for DHS using a survey of 1000 randomly selected households living in buildings with IHS. A mixture model is applied to deal with the zero WTP responses. The WTP distribution is specified as a mixture of two distributions, one with a point mass at zero and the other with full support on the positive half of the real line. The results show that the mean additional WTP for DHS-based RH over IHS-based RH is estimated to be KRW 5775 (USD 5.4 per Gcal. This value can be interpreted as the consumer’s convenience benefits of DHS over IHS, and amounts to approximately 6.0% of the average price: KRW 96,510 (USD 90.4 per Gcal in 2013, for IHS-based RH. This information is useful for evaluating changes to the method used for supplying RH from IHS to DHS.

  16. Long-term Green Innovation Opportunities Within the Hungarian District Heating Sector Towards 2030

    Directory of Open Access Journals (Sweden)

    Horvath Balint

    2016-07-01

    Full Text Available Natural gas is still the primary input of the Hungarian heating and cooling systems, therefore it still makes most of the overheads. One of the main obstacles of a competitive district heating system is the public opinion which still considers this service more expensive than the traditional heating forms. According to the absolute numbers this assumption might be valid but from a more accurate economic perspective, heat production has more aspects to stress. Most people forget about the simple fact that the maintenance costs of natural gas based systems are rather outsourced to the consumer than in the case of district heating. Furthermore, the uneven rate of the fixed and variable costs of this technology does not prove to be optimal for service developments. Investigating the future tendencies highlight that encouraging the efficiency improvement of district heating and the spread of technological innovation in the sector does not belong to the top priorities. Still, avoiding this problem it could lead serious deadweight losses in the case of the heating sector.

  17. Optimal Hierarchical Decision-Making for Heat Source Selection of District Heating Systems

    Directory of Open Access Journals (Sweden)

    Fang Fang

    2014-01-01

    Full Text Available With the rapid development of China’s urbanization, the proportion between the heating consumption and the energy consumption of the whole society keeps rising in recent years. For a district heating system, the selection of the heat source makes significant impact on the energy efficiency and the pollutant emissions. By integrating the methods of the Analytic Hierarchy Process (AHP and the Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE, a multiple-attribute decision-making scheme for the heat source selection of district heating systems is proposed in this paper. As a core part of this scheme, a comprehensive benefit index with hierarchical parallel structure is constructed. The economic benefit, environment benefit, and technical benefit can be reflected with a certain percentage in the comprehensive benefit index. To test the efficiency of the proposed scheme, a case study for a large-scale district heating system in Beijing is carried out, where five kinds of heat sources (water source heat pump, ground source heat pump, gas-fired boiler, coal-fired boiler, and oil-fired boiler are taken into account. The analysis and instructions for the final sorting result are also demonstrated.

  18. Electricity eliminates rust from district heat pipes. The new deoxidation method works on radiators

    Energy Technology Data Exchange (ETDEWEB)

    Sonninen, R.; Leisio, C.

    1996-11-01

    Oxygen dissolving in district heating water through district heat pipes and pipe joints made of plastic corrodes many small and medium-size district heating systems, resulting in heat cuts in the buildings connected to these systems. IN some cases, corrosion products have even circulated back to district heating power plants, thus hampering heat generation in the worst of cases. People residing in blocks of flats where some radiator components are made of plastic also face a similar problem, though on a smaller scale. A small and efficient electrochemical deoxidation cell has now been invented to eliminate this nuisance, which occurs particularly in cold winter weather. (orig.)

  19. Electricity eliminates rust from district heat pipes. The new deoxidation method works on radiators

    Energy Technology Data Exchange (ETDEWEB)

    Sonninen, R.; Leisio, C.

    1996-11-01

    Oxygen dissolving in district heating water through district heat pipes and pipe joints made of plastic corrodes many small and medium-size district heating systems, resulting in heat cuts in the buildings connected to these systems. IN some cases, corrosion products have even circulated back to district heating power plants, thus hampering heat generation in the worst of cases. People residing in blocks of flats where some radiator components are made of plastic also face a similar problem, though on a smaller scale. A small and efficient electrochemical deoxidation cell has now been invented to eliminate this nuisance, which occurs particularly in cold winter weather. (orig.)

  20. Possibility of using adsorption refrigeration unit in district heating network

    Science.gov (United States)

    Grzebielec, Andrzej; Rusowicz, Artur; Jaworski, Maciej; Laskowski, Rafał

    2015-09-01

    Adsorption refrigeration systems are able to work with heat sources of temperature starting with 50 °C. The aim of the article is to determine whether in terms of technical and economic issues adsorption refrigeration equipment can work as elements that produce cold using hot water from the district heating network. For this purpose, examined was the work of the adsorption air conditioning equipment cooperating with drycooler, and the opportunities offered by the district heating network in Warsaw during the summer. It turns out that the efficiency of the adsorption device from the economic perspective is not sufficient for production of cold even during the transitional period. The main problem is not the low temperature of the water supply, but the large difference between the coefficients of performance, COPs, of adsorption device and a traditional compressor air conditioning unit. When outside air temperature is 25 °C, the COP of the compressor type reaches a value of 4.49, whereas that of the adsorption device in the same conditions is 0.14. The ratio of the COPs is 32. At the same time ratio between the price of 1 kWh of electric power and 1 kWh of heat is only 2.85. Adsorption refrigeration equipment to be able to compete with compressor devices, should feature COPads efficiency to be greater than 1.52. At such a low driving temperature and even changing the drycooler into the evaporative cooler it is not currently possible to achieve.

  1. Local or district heating by natural gas: Which is better from energetic, environmental and economic point of views?

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Noro, M. [Department of Management and Engineering, University of Padova, Stradella S. Nicola, 3-36100 Vicenza (Italy)

    2006-02-01

    Generally, a CHP plant coupled with district heating is considered more efficient than traditional local heating systems from an economic and environmental point of view. This is certainly true for municipal waste CHP plants, but for plants fuelled by natural gas the important developments of the last years regarding both boilers (premixed and modulating burners, condensing boilers, etc.) and mechanical vapour compression and absorption heat pumps can change the traditional view. At the same time also district heating plants improved. Therefore it is worth to analyse the whole matter comparing advantages and disadvantages of the different alternatives, with a wide difference between them. The paper reports on the analysis of major district heating natural gas based technologies (vapour and gas turbines, internal combustion engine, combined cycles); the cost of heat and power produced in these plants is compared to the cost of producing the same quantity of electrical energy by a reference GTCC-Gas Turbine Combined Cycle (actually the most efficient technology for pure electrical production) and the cost of heat production by modern local heating technologies using natural gas as fuel (condensing boilers, electrical, gas engine and absorption heat pumps). Regarding energy efficiency and emissions, modern local heating turns out to be more efficient than district heating for most CHP technologies. However, the same does not happen from an economic point of view, because in Italy natural gas used by cogeneration plants is subjected to a much lower taxation than local heating technologies. (author)

  2. A Thermoeconomic Approach for the Analysis of District Heating Systems

    Directory of Open Access Journals (Sweden)

    Michele Calí

    2001-12-01

    Full Text Available

    District heating is a rational way to use fossil fuels for domestic heating (and cooling in towns, especially if it is joined with a cogenerative production of electricity. As with every other process it must be economically convenient for its realization, so technical considerations must be integrated into the economic ones. Thermoeconomic theories take into account these two aspects, representing a good tool for an optimized design and correct management (Bejan et al. 1996.

    The aim of this paper is to propose the use of thermoeconomic procedures for the analysis of district heating systems, in order to define criteria for the network design. The approach consists of the choice of significant design parameters, which can be varied in order to determine the optimized system.

    An application to the Turin district heating system is presented here. The system is composed of a steam power plant and a gas turbine power plant, both cogenerative, and of the pipe network. The effects of the choices in the network project on the working conditions of the system and on the cost of its products are shown. The optimization problem has been solved by evaluating the decision variable under some particular conditions, obtained by solving fluid-dynamic, thermal and thermoeconomic problems for the whole system, corresponding to different values of the supply fluid temperature.

    The application of the thermoeconomic theory to the network allows one to determine the effects of the parameters characterizing each user to the cost of the service provided. This information constitutes a tool for making management decisions, like the opportunity and modality for future expansions of the served area.

  3. Particulate matter emissions from combustion of wood in district heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Ghafghazi, S. [University of British Columbia, Vancouver; Sowlati, T. [University of British Columbia, Vancouver; Sokhansanj, Shahabaddine [ORNL; Bi, X.T. [University of British Columbia, Vancouver; Melin, Staffan [Delta Research Corporation

    2011-01-01

    The utilization of wood biomass to generate district heat and power in communities that have access to this energy source is increasing. In this paper the effect of wood fuel properties, combustion condition, and flue gas cleaning system on variation in the amount and formation of particles in the flue gas of typical district heating wood boilers are discussed based on the literature survey. Direct measurements of particulate matter (PM) emissions from wood boilers with district heating applications are reviewed and presented. Finally, recommendations are given regarding the selection of wood fuel, combustion system condition, and flue gas cleaning system in district heating systems in order to meet stringent air quality standards. It is concluded that utilization of high quality wood fuel, such as wood pellets produced from natural, uncontaminated stem wood, would generate the least PM emissions compared to other wood fuel types. Particulate matter emissions from grate burners equipped with electrostatic precipitators when using wood pellets can be well below stringent regulatory emission limit such as particulate emission limit of Metro Vancouver, Canada.

  4. Changes in heat load profile of typical Danish multi-storey buildings when energy-renovated and supplied with low-temperature district heating

    DEFF Research Database (Denmark)

    Harrestrup, Maria; Svendsen, Svend

    2013-01-01

    end-use savings are implemented in buildings concurrent with the application of low-temperature district heating (LTDH), the heat profiles of the buildings will change. Reducing peak loads is important, since this is the dimensioning foundation for future district heating systems. To avoid oversized...... RE-based capacity, a long-term perspective needs to be taken. Applying LTDH in existing buildings without changing the heating system implies reduced radiator performance, so it is of great importance that acceptable comfort temperatures can still be provided. The results indicate that it is possible...

  5. Heating of tap water in houses caused by district heating; Opwarmen leidingwater in woningen t.g.v. stadsverwarming

    Energy Technology Data Exchange (ETDEWEB)

    Van Wolferen, H. [TNO Bouw en Ondergrond, Apeldoorn (Netherlands)

    2007-07-15

    Practical research has been conducted on the option of heating tap water in houses due to district heating. Based on the results, guidelines are developed to prevent drinking water from being heated. The installation has been surveyed in 30 houses and in 24 of these houses temperatures have also been measured. Unwanted heating of drinking water, which occurred in 8 houses, can easily be solved by making minor adjustments to the installation with the aim of reducing heating. [mk]. [Dutch] Een praktijkonderzoek is uitgevoerd naar de eventuele opwarming van leidingwater in woningen t.g.v. stads- of blokverwarming. Op basis van de resultaten worden richtlijnen ontwikkeld om opwarmen van drinkwater te voorkomen. In 30 woningen is de installatie geschouwd en in 24 van deze woningen zijn tevens temperatuurmetingen uitgevoerd. In 8 woningen waarin ongewenste opwarming van drinkwater optreedt zijn eenvoudige aanpassingen aan de installatie verricht met als doel de opwarming te beperken.

  6. Initial economic appraisal of nuclear district heating in France

    Directory of Open Access Journals (Sweden)

    Jasserand Frédéric

    2016-01-01

    Full Text Available Although cogeneration with nuclear power has been proving its feasibility for many years and in many parts of the world, the French nuclear fleet does not use this technique. Nevertheless, current developments within the energy context may offer new opportunities to review the use of nuclear cogeneration. This paper focuses on the use of cogeneration for district heating and its possible development perspectives within the French energy transition. After recapping some common assumptions about nuclear cogeneration, we will describe the techno-economic model that we built to evaluate the characteristics of introducing cogeneration into an already operating power plant. The second step consists in applying the above-described model to a use-case describing the heating of the Parisian area, which represents the largest target for this study. The last step presents the results of a simplified model derived from the first step. Summarizing the model's main input data in a few pertinent parameters gives an initial picture of the potential for developing nuclear district heating in France.

  7. A new method of laying of district heating pipes

    Energy Technology Data Exchange (ETDEWEB)

    Claesson, C.; Persson, C.; Jarfelt, U. [Department of Building Technology, Chalmers University of Technology, Goeteborg (Sweden); Ramnaes, O. [Department of Chemical Environmental Science, Chalmers University of Technology, Goeteborg (Sweden)

    2004-07-01

    A new method of laying of district heating pipes is described with its advantages and disadvantages. The method has earlier been applied to installation of gas pipes and broadband, but has to our knowledge never been used in connection to district heating. The method aims at shortening the laying time and minimising the impact on the asphalt layer, thus reducing the laying costs. The idea is to cold install the pipes into a milled, narrow and shallow trench that is refilled with foam concrete. Environmental impacts caused by the new laying method are studied in comparison with the traditional laying method. Emissions of carbon dioxide, nitrogen oxides and sulphur dioxide to air from activities differing between the two laying methods during construction of DN40 twin pipe networks are considered as well as emissions related to distribution heat losses from the networks. There is no environmental objective against using the new method considering the studied emissions. Laying according to the new and the traditional method cause emissions of the same order of magnitude. Calculated temperature of the casing does not indicate any problem with accelerated thermal oxidation of the casing pipe due to laying in the thermally insulating foam concrete. (orig.)

  8. A modeling approach for district heating systems with focus on transient heat transfer in pipe networks

    DEFF Research Database (Denmark)

    Mohammadi, Soma; Bojesen, Carsten

    2015-01-01

    finite element method is applied to simulate transient temperature changes in pipe networks. The model is calculating time series data related to supply temperature to the DHN from heat production units, heat loads and return temperature related to each consumer to calculate dynamic temperature changes...... district heating networks [DHN] characteristics. This paper is presenting a new developed model, which reflects the thermo-dynamic behavior of DHN. It is designed for tree network topologies. The purpose of the model is to serve as a basis for applying a variety of scenarios towards lowering...... the temperature in DH systems. The main focus is on modeling transient heat transfer in pipe networks regarding the time delays between the heat supply unit and the consumers, the heat loss in the pipe networks and the consumers’ dynamic heat loads. A pseudo-dynamic approach is adopted and also the implicit...

  9. 4{sup th} conference of the Swiss District Heating Association - Who knows the advantages of district heating?; Wer kennt die Vorzuege der Fernwaerme?

    Energy Technology Data Exchange (ETDEWEB)

    Sigrist, L.

    2005-07-01

    This comprehensive article discusses the possibilities and advantages offered by the increased use of district heating systems in Switzerland. Comparisons are made between the use of district heating in Switzerland and in Denmark, where almost the half of heating requirements are met by district heating systems. The article summarises the contributions presented at the conference by various experts from Switzerland and abroad, including energy and climate-change expert H.U. von Weizsaecker. Topics covered range from dwindling oil resources, global warming and energy prognoses to the price and availability of fossil resources in general. Arguments in favour of district heating systems are presented. Also, the external costs of various forms of energy are discussed, as are strategies for the promotion of district heating systems. The role to be played by district heating systems in bridging the gap between fossil fuels and the use of renewable energy sources is examined and the use of wood-fired district heating systems is looked at.

  10. Fourth conference of the Swiss District Heating Association - Who knows the advantages of district heating?; Wer kennt die Vorzuege der Fernwaerme?

    Energy Technology Data Exchange (ETDEWEB)

    Sigrist, L

    2005-07-01

    This comprehensive article discusses the possibilities and advantages offered by the increased use of district heating systems in Switzerland. Comparisons are made between the use of district heating in Switzerland and in Denmark, where almost the half of heating requirements are met by district heating systems. The article summarises the contributions presented at the conference by various experts from Switzerland and abroad, including energy and climate-change expert H.U. von Weizsaecker. Topics covered range from dwindling oil resources, global warming and energy prognoses to the price and availability of fossil resources in general. Arguments in favour of district heating systems are presented. Also, the external costs of various forms of energy are discussed, as are strategies for the promotion of district heating systems. The role to be played by district heating systems in bridging the gap between fossil fuels and the use of renewable energy sources is examined and the use of wood-fired district heating systems is looked at.

  11. Potential of biocorrosion in Danish district heatings sytems

    Energy Technology Data Exchange (ETDEWEB)

    Kjellerup, B.V.; Olesen, B.H.; Froelund, B. [Danish Technological Institute, Dep. of Environment Teknologiparken, Arhus (Denmark); Nielsen, P.H. [Aalborg University, Department of Life Sciences, Aalborg (Denmark)

    2004-07-01

    Danish district heating (DH) systems utilise water with unique characteristics that include low conductivity, high pH, nutrient poor and anaerobic (oxygen free) conditions in order to reduce corrosion rates. This survey was carried out in order to investigate the potential for biofilm formation and biocorrosion in these systems. Determination of total bacterial numbers in water samples were performed in 29 DH systems and showed a range of 10{sup 2}-10{sup 5} cells . ml{sup -1}. The potential for biofilm growth was further examined in corrosion monitoring units located at 6 DH locations. Total bacterial numbers in biofilm on mild steel were found in the range of 10{sup 4}-10{sup 6} cells . cm{sup -2}. The mild steel coupons were examined for general corrosion rates based on weight loss together with an investigation of pitting corrosion. The general corrosion rates were up to 12 {mu}m . year{sup -1}, while the pitting analysis showed pit depths up to 90 {mu}m for half a year of exposure. Presence of sulphate reducing bacteria (SRB) was found in all systems tested with corrosion monitoring units, whereas sulphide was found to different extents in the biofilms on all mild steel coupons. It was shown that DH systems with the highest number of bacteria in the biofilm generally had the most pronounced corrosion. The results show that despite the nutrient poor environment in the DH systems the potential for biofilm formation and biocorrosion was present. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

  12. District heating. Fernwaerme. Technik und Wirtschaftlichkeit - Angebot und Nachfrage bis 1990 - Energieeinsparung und Oekologie

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, R.; Gruening, F.; Purper, G.

    1982-01-01

    In some countries, some very extensive investigations on the possibilities of an increased expansion of district heating have been finished by now. These investigations were analysed, compared, and used in this report. The main goal of this investigation was to determine the possibilities of connections to the district heating network from the final consumer's point of view and to analyse the factors influencing this process. This analysis from the consumer's view-point is preceded by an outline of the state of the art and development trends in district heat supply. This supplementary information is made to define the main components of the district heat supply system and briefly describe technical factors of the system. It is, however, not an assessment of company-specific components. The report ends with statements on the energy-political and ecological importance of district heating and shows for the example of the FRG, possibilities of supporting the district heating section.

  13. Optimized design of district heating networks; Optimierte Auslegung von Nahwaermenetzen

    Energy Technology Data Exchange (ETDEWEB)

    Bestrzynski, Georg K.; Scholl, Stephan [Technische Univ. Braunschweig (Germany). Inst. fuer Chemische und Thermische Verfahrenstechnik; Janssen, Holger [Hochschule Hannover (Germany). Inst. fuer Energie und Klimaschutz; Luke, Andrea [Kassel Univ. (Germany). Fachgebiet fuer Technische Thermodynamik

    2012-07-01

    The construction of heating networks with small spatial dimensions and total power consumption, so-called district heating networks, is one of the key drivers for the capacity expansion of this climate-efficient technology. The widely spread implementation of cogeneration power plants with very large primary energy efficiencies in these networks specifies the reasons for the ecological special position of this technology. Unfortunately, however, there are many technical, economic and socio-economic barriers against a rapid proliferation of this technology. In line with the research project 'Possibilities and limits of district heating networks in rural structured areas under consideration of renewable energies', the resistance against a rapid expansion of capacity of this technology is to be reduced. Due to the close linkage of economic and technological shortcomings and economic presentability, the economic interests of (potential) operators are represented better. Primarily, the interactions of power, heat demand and settlement structures as well as the concepts to ensure the task of heat supply are the focus of the research activities. The integrability of continuous and discontinuous units for heat supply such as (CHP) and solar thermal systems shall be examined in more detail as well as the suitability of innovative technologies for the implementation into such local heating networks. Here, adsorption chillers are of particular interest. By implementation of adsorption chillers, cogenerations can be expanded ecologically to trigeneration plants. In addition to the described activities, also socio-economic field studies on the heat consumers are performed in order to support the selection of technical solutions. Thereby, the research project under consideration is supported by the European Regional Development Fund (ERDF) and the Lower Saxony Ministry for Science and Culture (MWK). This research project is performed in a research consortium between

  14. Possibility of using adsorption refrigeration unit in district heating network

    Directory of Open Access Journals (Sweden)

    Grzebielec Andrzej

    2015-09-01

    Full Text Available Adsorption refrigeration systems are able to work with heat sources of temperature starting with 50 °C. The aim of the article is to determine whether in terms of technical and economic issues adsorption refrigeration equipment can work as elements that produce cold using hot water from the district heating network. For this purpose, examined was the work of the adsorption air conditioning equipment cooperating with drycooler, and the opportunities offered by the district heating network in Warsaw during the summer. It turns out that the efficiency of the adsorption device from the economic perspective is not sufficient for production of cold even during the transitional period. The main problem is not the low temperature of the water supply, but the large difference between the coefficients of performance, COPs, of adsorption device and a traditional compressor air conditioning unit. When outside air temperature is 25 °C, the COP of the compressor type reaches a value of 4.49, whereas that of the adsorption device in the same conditions is 0.14. The ratio of the COPs is 32. At the same time ratio between the price of 1 kWh of electric power and 1 kWh of heat is only 2.85. Adsorption refrigeration equipment to be able to compete with compressor devices, should feature COPads efficiency to be greater than 1.52. At such a low driving temperature and even changing the drycooler into the evaporative cooler it is not currently possible to achieve.

  15. Annex to Solar heat storages in district heating networks. Comprehensive list of Danish literature and R and D projects

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K. (Ellehauge og Kildemoes, AArhus (DK)); Engberg Pedersen, T. (COWI A/S, Kgs. Lyngby (DK))

    2007-07-15

    This annex relates to the report 'Solar heat storages in district heating networks', which has been elaborated to inform about the Danish experiences and findings on the use of central solar heating plants in district heating networks, especially with the focus on the development of the storage part of the systems. The report has been funded as part of the IEE PREHEAT cooperation and by Energinet.dk, project no. 2006-2-6750. (au)

  16. Predicting the Heat Consumption in District Heating Systems using Meteorological Forecasts

    DEFF Research Database (Denmark)

    Nielsen, Henrik Aalborg, orlov 31.07.2008; Madsen, Henrik

    Methods for on-line prediction of heat consumption in district heating systems hour by hour for horizons up to 72 hours are considered in this report. Data from the district heating system Vestegnens Kraftvarmeselskab I/S is used in the investigation. During the development it has been assumed...... that meteorological forecasts are available on-line. Such a service has recently been introduced by the Danish Meteorological Institute. However, actual meteorological forecasts has not been available for the work described here. Assuming the climate to be known the mean absolute relative prediction error for 72 hour......, this is somewhat contrary to practice. The work presented is a demonstration of the value of the so called gray box approach where theoretical knowledge about the system under consideration is combined with information from measurements performed on the system in order to obtain a mathematical description...

  17. Natural refrigerants. Future heat pumps for district heating; Naturliga koeldmedier. Framtida vaermepumpar foer fjaerrvaerme

    Energy Technology Data Exchange (ETDEWEB)

    Ingvarsson, Paul; Steen Ronnermark, Ingela [Fortum Teknik och Miljoe AB, Stockholm (Sweden); Eriksson, Marcus [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Chemical Engineering and Environmental Science

    2004-01-01

    International work on refrigerants is aiming at phasing out HFC. The solution might be natural refrigerants. Within 15-20 years, when present heat pumps for district heating in Sweden are likely not in service any longer, it might still be good economy to install new heat pumps since only the machines need to be replaced. This report describes the possibilities to use natural refrigerants. A first screening resulted in further study on some hydrocarbons, ammonia and carbon dioxide. Water was considered to require too large volumes. In present plants it is practically not possible to use any natural refrigerants, partly because the compressors are not adapted. In new plants the situation is different. Today it is technically possible to install new heat pumps in the studied size, 15 MW{sub th}, using ammonia or hydrocarbons as refrigerant. But likely it is very difficult to get permits from authorities since the refrigerants are toxic or highly flammable. There is substantial international research on using carbon dioxide, and this refrigerant is also used in some applications. Carbon dioxide is used at high pressure and in a trans-critical process. Surprisingly, it turned out that one compressor manufacturer considers it possible to supply a heat pump for district heating within 5 years. This development has taken place in Russia, mainly for domestic use. Thus, within 15 to 20 years there will probably exist a technique where carbon dioxide is used. However, more development is needed. Additionally, low district heating return temperatures are also needed to get an acceptable COP. The investment cost for a heat pump installation is considered to be approx. 30 % higher when using ammonia or propane compared to using R134a. When using carbon dioxide there is in the longer run potential to get lower cost than for R134a. The COPs are almost identical if the systems are properly designed. In the carbon dioxide case the COP is somewhat lower, but has a potential for

  18. Low-energy district heating in energy-efficient building areas

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro; Christensen, Jørgen Erik

    2011-01-01

    This paper presents an innovative low-energy district heating (DH) concept based on low-temperature operation. The decreased heating demand from low-energy buildings affects the cost-effectiveness of traditionally-designed DH systems, so we carried out a case study of the annual energy performance...... of a low-energy network for low-energy houses in Denmark. We took into account the effect of human behaviour on energy demand, the effect of the number of buildings connected to the network, a socio-economic comparison with ground source heat pumps, and opportunities for the optimization of the network...... design, and operational temperature and pressure. In the north-European climate, we found that human behaviour can lead to 50% higher heating demand and 60% higher heating power than those anticipated in the reference values in the standard calculations for energy demand patterns in energy-efficient...

  19. Optimized district heating supply temperature for large networks; Optimerad framledningstemperatur foer stora fjaerrvaermenaet

    Energy Technology Data Exchange (ETDEWEB)

    Saarinen, Lisa; Boman, Katarina

    2012-02-15

    The supply temperature of the Uppsala district heating network was optimized using a model-based control strategy. Simulation of the network showed that the supply temperature could be decreased by in average 8 deg and the electricity production of the plants supplying the network could be increased with 2.5 % during the period January- April, giving an extra income of 1.2 MSEK due to increased income from electricity sales

  20. Techno-economic analysis of a local district heating plant under fuel flexibility and performance

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse

    2017-01-01

    Brovst is a small district in Denmark. This paper analyses the use of local renewable resources in the district heating systems of Brovst. The present use of fossil fuels in the Brovst district heating plant (DHP) represents an increasing environmental and climate-related load. Therefore, an inve......Brovst is a small district in Denmark. This paper analyses the use of local renewable resources in the district heating systems of Brovst. The present use of fossil fuels in the Brovst district heating plant (DHP) represents an increasing environmental and climate-related load. Therefore......, an investigation has been made to reduce the use of fossil fuels for district heating system and make use of the local renewable resources (biogas, solar, and heat pump) for district heating purposes. In this article, the techno-economic assessment is achieved through the development of a suite of models......PRO, which has been used to analyze the integration of a large-scale energy system into the domestic district heating system. A model of the current work on the basis of information from the Brovst plant (using fossil fuel) is established and named as a reference option. Then, four other options...

  1. Geothermal energy potential for district and process heating applications in the U. S. : an economic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Bloomster, C.H.; Fassbender, L.L.; McDonald, C.L.

    1977-08-01

    Geothermal energy is competitive for space and process heating applications over significant distances when employed on a large scale to serve concentrated markets. Under these conditions geothermal energy from 90 to 150/sup 0/C hydrothermal resources should be economically competitive for high-density urban district heating out to distances of 50 miles from the wellhead. Supply curves (price-quantity relationships) were developed for both process heating and district heating applications for distances out to 50 miles. The 90 to 150/sup 0/C hydrothermal resources, which were identified in the assessment of geothermal resources by the U.S. Geological Survey, contain usable energy for space and process heat equivalent to 50 billion barrels of oil. The potential demand for space and process heat near these hydrothermal resources is large; over 10% of the U.S. population resides within 40 miles of the resources. The sensitivity of production costs to the important factors of production was determined. The most important factors are well costs, well flow rate, resource temperature, distance separating demand and supply, population density, size of demand, and the system load factor. Technological advances are needed to reduce costs and increase the distances over which geothermal energy can be competitive. Institutional deterrents to widespread nonelectric applications of geothermal energy will probably be significant. Among these will be the acquisition of rights-of-way, the need to organize concentrated markets, and price competition from the conventional fuels based on average cost rather than marginal cost.

  2. The role of district heating in the future Danish energy system

    DEFF Research Database (Denmark)

    Münster, Marie; Morthorst, Poul Erik; Larsen, Helge V.

    2012-01-01

    In the EU and in Denmark, the aim is to reduce dependence on fossil fuels and to use energy more efficiently. District heating and combined heat and power have significant potential with regard to achieving this aim. New technologies may make individual solutions such as electric heating, heat...... pumps and micro-CHP more attractive than previously. Therefore, the competitive conditions between district heating and other types of heating may change in the future. The question is therefore whether district heating can contribute to ensuring the sustainability of future energy systems? Denmark...... is used as a case as the country has a high share of district heating and produces 20% of the electricity with wind power. The analyses are carried out using the electricity market model Balmorel, which facilitates cost optimization of operation and investments in energy production plants as well...

  3. Book of abstracts: International Conference on Smart Energy Systems and 4th Generation District Heating

    DEFF Research Database (Denmark)

    It is a great pleasure to welcome you to the first International Conference on Smart Energy Systems and 4th Generation District Heating at Aalborg University, Copenhagen Campus on 25-26 August 2015. The conference is organised by the 4DH Strategic Research Centre in collaboration with Aalborg......-temperature district heating, the Strategic Research Centre for 4th Generation District Heating Technologies and Systems enhances the understanding of supply system design, infrastructure and heat savings. In future energy systems, combinations of low-temperature district heating resources and heat savings represent...... a promising alternative to individual heating solutions and passive or energy+ buildings. This change in the heating system also requires institutional and organisational changes that address the implementation of new technologies and enable new markets that can provide feasible solutions to society. We hope...

  4. Comparison of district heating systems used in China and Denmark

    DEFF Research Database (Denmark)

    Zhang, Lipeng; Li, Hongwei; Gudmundsson, Oddgeir

    2013-01-01

    An overview of the technological differences between the district heating (DH) system used in China and Denmark is discussed. Although the Chinese DH systems are primarily fueled by coal and it is expected to remain this way in the near future, the reduction of network temperatures is a very...... important step towards increasing energy efficiency. If the Danish and the Chinese systems are compared from plant to consumer it can be seen that the Danish DR apply pre-insulated pipes, twin pipes where possible, with high insulation properties compared to the Chinese systems that generally apply single...... pipes with insulation typically added on-site. In Danish networks the control is situated in substations close to the consumers while in Chinese networks control is situated in big area substations. DHW is prepared by DR in Denmark while it is generally prepared by individual solutions in China...

  5. Comparison of corrosion monitoring techniques in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Nielsen, Lars Vendelbo; Thorarinsdottir, R.I.

    2004-01-01

    Investigations aimed at evaluating monitoring techniques as a function of the specific water chemistry has been conducted as a part of a Nordic project focused on improving the quality of corrosion monitoring in municipal district heating. A combination of techniques has been selected to measure...... both general and localised corrosion. Electrochemical techniques (LPR, EIS) as well as direct techniques (high sensitive ER, weight loss, local crevice corrosion current) have been applied. The data show that the water quality in Danish systems is high resulting in low corrosion rates, but changes...... in the water quality induce localised corrosion. Useful monitoring results have been obtained with high sensitive ER technique (MetriCorr) and crevice corrosion measurements with the LOCORR cell (FORCE TECHNOLOGY)....

  6. District heating marketing. Strategies in the heating market. 2. ed.; Fernwaerme-Marketing. Strategien im Waermemarkt

    Energy Technology Data Exchange (ETDEWEB)

    Marschalleck, Helmut [MVV Energie AG, Mannheim (Germany); Arndt, Andreas [EnBW Vertriebs- und Servicegesellschaft, Karlsruhe (Germany); Behm, Norman [Stadtwerke Rostock AG (Germany)] [and others

    2012-07-01

    The assistance in the strategic and operational planning of an individual marketing strategy in the district heating market is the focus of the book under consideration. Starting from the definition of the actual situation (market analysis and marketing potential) and the strategic goal, a marketing concept and a marketing mix (product policy, pricing policy, distribution policy as well as communication policy) is established. Subsequently, the tools of the marketing controlling (incoming orders and turnover, marketing key performance indicators, reporting, marketing audit) are described.

  7. Innovation in the district heating. Process study in February 2012; Innovasjon i fjernvarme. Prossesstudie februar 201

    Energy Technology Data Exchange (ETDEWEB)

    Hoey, Mads Bruun

    2012-07-01

    This process study shows that, in order to create more innovation for growth in the district heating sector, it requires a new initiative, carried out by the district heating companies themselves, in the areas described in the study. This is regarded as the opportunities that the program should look for and will be more complete by the descriptions of the workshop results. (eb)

  8. Energetic and Exergetic Analysis of Low and Medium Temperature District Heating Network Integration

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    In this paper, energetic and exergetic approaches were applied to an exemplary low temperature district heating (LTDH) network with supply/return water temperature at 55oC/25 oC. The small LTDH network is annexed to a large medium temperature district heating (MTDH) network. The LTDH network can...

  9. Down-Hole Heat Exchangers: Modelling of a Low-Enthalpy Geothermal System for District Heating

    Directory of Open Access Journals (Sweden)

    M. Carlini

    2012-01-01

    Full Text Available In order to face the growing energy demands, renewable energy sources can provide an alternative to fossil fuels. Thus, low-enthalpy geothermal plants may play a fundamental role in those areas—such as the Province of Viterbo—where shallow groundwater basins occur and conventional geothermal plants cannot be developed. This may lead to being fuelled by locally available sources. The aim of the present paper is to exploit the heat coming from a low-enthalpy geothermal system. The experimental plant consists in a down-hole heat exchanger for civil purposes and can supply thermal needs by district heating. An implementation in MATLAB environment is provided in order to develop a mathematical model. As a consequence, the amount of withdrawable heat can be successfully calculated.

  10. Method for optimal design of pipes for low-energy district heating, with focus on heat losses

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro; Li, Hongwei; Svendsen, Svend

    2011-01-01

    The synergy between highly energy-efficient buildings and low-energy district heating (DH) systems is a promising concept for the optimal integration of energy-saving policies and energy supply systems based on renewable energy (RE). Network transmission and distribution heat loss is one of the key...... factors in the optimal design of low-energy DH systems. Various pipe configurations are considered in this paper: flexible pre-insulated twin pipes with symmetrical or asymmetrical insulation, double pipes, and triple pipes. These technologies represent potential energy-efficient and cost...... showed the influence of the soil temperature throughout the year. Finally, the article describes proposals for the optimal design of pipes for low-energy applications and presents methods for decreasing heat losses....

  11. Road map for district heating. The role of district heating in the energy system. Main report; Denmark; Roadmap for fjernvarmen. Fjernvarmens rolle i energisystemet. Hovedrapport

    Energy Technology Data Exchange (ETDEWEB)

    Hofmeister, M.; Aabye Moeller, A.; Eggert, A.; Bjerregaard, M. (Fjernvarmens Udviklingscenter, AArhus (Denmark)); Dyrelund, A. (Ramboell, Koebenhavn (Denmark)); OErsted Pedersen, H. (Ea Energianalyse, Koebenhavn (Denmark)); Lund, H. (Aalborg Univ., Aalborg (Denmark))

    2011-07-01

    In the recent years many studies of how Denmark can be fossil free by 2050 it is agreed that district heating will play a crucial role. District heating is an important factor of phasing out fossil fuels in an energy-and cost-effective way. But the future energy supply without fossil fuels poses new requirements for district heating. In the future, district heating shall provide energy for low-energy houses, have low distribution losses and use a variety of heat sources such as geothermal, solar, waste, surplus heat, CHP and various biomass con-version processes. In addition, it must all be done in an energy efficient way and in an active interaction with production of electricity and electricity consumption and, through integration of electricity from wind, solar and wave power. Low temperature, use of heat pumps and the interaction with electricity and biomass will be keywords. It is not only in Denmark we will need an active development of future technologies and systems. Large parts of Europe and many other parts of the world need the same development, and today Denmark has a significant export in the market - an export that has risen sharply, despite the recent economic recession. There is thus a double need to actively promote the development of future district heating technologies. We will partly need the technology development to realize the goal of a fossil free society and secondly because it is necessary to maintain and expand the export. This report contains a number of proposals for concrete actions - a roadmap for the development of district heating. The project is anchored at the District Energy Development Center that will work for an implementation of the concrete project ideas after the project completion. There is a need to increase the activity level for development of district heating. There is therefore a need to ensure financing of this development. We suggest that this can be done by creating an opportunity for a more sustained funding, for

  12. Road map for district heating. The role of district heating in the energy system. Summary report; Denmark; Roadmap for fjernvarmen. Fjernvarmens rolle i energisystemet. Resumerapport

    Energy Technology Data Exchange (ETDEWEB)

    Hofmeister, M.; Aabye Moeller, A.; Eggert, A.; Bjerregaard, M. (Fjernvarmens Udviklingscenter, AArhus (Denmark)); Dyrelund, A. (Ramboell, Koebenhavn (Denmark)); OErsted Pedersen, H. (Ea Energianalyse, Koebenhavn (Denmark)); Lund, H. (Aalborg Univ., Aalborg (Denmark))

    2011-07-01

    In the recent years many studies of how Denmark can be fossil free by 2050 it is agreed that district heating will play a crucial role. District heating is an important factor of phasing out fossil fuels in an energy-and cost-effective way. But the future energy supply without fossil fuels poses new requirements for district heating. In the future, district heating shall provide energy for low-energy houses, have low distribution losses and use a variety of heat sources such as geothermal, solar, waste, surplus heat, CHP and various biomass con-version processes. In addition, it must all be done in an energy efficient way and in an active interaction with production of electricity and electricity consumption and, through integration of electricity from wind, solar and wave power. Low temperature, use of heat pumps and the interaction with electricity and biomass will be keywords. It is not only in Denmark we will need an active development of future technologies and systems. Large parts of Europe and many other parts of the world need the same development, and today Denmark has a significant export in the market - an export that has risen sharply, despite the recent economic recession. There is thus a double need to actively promote the development of future district heating technologies. We will partly need the technology development to realize the goal of a fossil free society and secondly because it is necessary to maintain and expand the export. This report contains a number of proposals for concrete actions - a roadmap for the development of district heating. The project is anchored at the District Energy Development Center that will work for an implementation of the concrete project ideas after the project completion. There is a need to increase the activity level for development of district heating. There is therefore a need to ensure financing of this development. We suggest that this can be done by creating an opportunity for a more sustained funding, for

  13. Comparison of Low-temperature District Heating Concepts in a Long-Term Energy System Perspective

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Østergaard, Dorte Skaarup; Yang, Xiaochen

    2017-01-01

    District heating systems are important components in an energy efficient heat supply. With increasing amounts of renewable energy, the foundation for district heating is changing and the approach to its planning will have to change. Reduced temperatures of district heating are proposed...... as a solution to adapt it to future renewable energy systems. This study compares three alternative concepts for district heating temperature level: Low temperature (55/25 oC), Ultra-low temperature with electric boosting (45/25 oC), and Ultra-low temperature with heat pump boosting (35/20 oC) taking...... into account the grid losses, production efficiencies and building requirements. The scenarios are modelled and analysed in the analysis tool EnergyPLAN and compared on primary energy supply and socioeconomic costs. The results show that the low temperature solution (55/25 oC) has the lowest costs, reducing...

  14. Towards a Future of District Heating Systems with Low-Temperature Operation together with Non-Fossil Fuel Heat Sources

    DEFF Research Database (Denmark)

    Tol, Hakan; Dinçer, Ibrahim; Svendsen, Svend

    2012-01-01

    This study focused on investigation of non-fossil fuel heat sources to be supplied to low-energy district heating systems operating in low temperature such as 55 C and 25 C in terms of, respectively, supply and return. Vast variety of heat sources classed in categories such as fossil fuel, renewa...

  15. The TX-model - a quantitative heat loss analysis of district heating pipes by means of IR surface temperature measurements

    Energy Technology Data Exchange (ETDEWEB)

    Zinki, Heimo [ZW Energiteknik, Nykoeping (Sweden)

    1996-11-01

    The aim of this study was to investigate the possibility of analysing the temperature profile at the ground surface above buried district heating pipes in such a way that would enable the quantitative determination of heat loss from the pair of pipes. In practical applications, it is supposed that this temperature profile is generated by means of advanced IR-thermography. For this purpose, the principle of the TX - model has been developed, based on the fact that the heat losses from pipes buried in the ground have a temperature signature on the ground surface. Qualitative analysis of this temperature signature is very well known and in practical use for detecting leaks from pipes. These techniques primarily make use of relative changes of the temperature pattern along the pipe. In the quantitative heat loss analysis, however, it is presumed that the temperature profile across the pipes is related to the pipe heat loss per unit length. The basic idea is that the integral of the temperature profile perpendicular to the pipe, called TX, is a function of the heat loss, but is also affected by other parameters such as burial depth, heat diffusivity, wind, precipitation and so on. In order to analyse the parameters influencing the TX- factor, a simulation model for the energy balance at the ground surface has been developed. This model includes the heat flow from the pipe to the surface and the heat exchange at the surface with the environment due to convection, latent heat change, solar and long wave radiation. The simulation gives the surprising result that the TX factor is by and large unaffected during the course of a day even when the sun is shining, as long as other climate conditions are relatively stable (low wind, no rain, no shadows). The results from the simulations were verified at different sites in Denmark, Finland, Sweden and USA through a co-operative research program organised and partially financed by the IEA District Heating Programme, Task III, and

  16. District heating supply for low energy areas. second edition; Fjernvarmeforsyning af lavenergiomraeder. 2 udgave

    Energy Technology Data Exchange (ETDEWEB)

    Kristjansson, H.; Buus, F. [Carl Bro as, Glostrup (Denmark); Boehm, B.; Vejen, N.K. [Danmarks Tekniske Univ., Kgs. Lyngby (Denmark); Rasmussen, J. [Star Pipe, Fredericia (Denmark); Paaske Christensen, K. [Nykoebing Falster Kommune, Nykoebing Falster (Denmark); Bidstrup, N. [Grundfos A/S, Broendby (Denmark)

    2004-08-01

    This report presents recommendations for design of district heating distribution systems in low energy buildings or in other areas with low heating density. For a joint heat supply of areas with low heat density distribution costs are high compared to heat sale. At the same time district heating flow pipes and pumps have developed significantly during the last decade. The project aims at identifying the optimal district heating distribution design for these conditions. The optimal design is dependent on heat price, price level and economic timeframe. Furthermore, savings are dependent of choice of frame of reference. Conditions can vary significantly from one area to another, but preconditions have been adapted to a reasonable level. (BA)

  17. District heating as the infrastructure for competition among fuels and technologies

    DEFF Research Database (Denmark)

    Grohnheit, Poul Erik; Mortensen, Bent Ole Gram

    2016-01-01

    District heating networks offer the possibility of competition between a wide range of fuels for combustion as well as technologies for comfort heat and cooling in buildings. For decades, cogeneration of electricity and heat for industrial processes or district heating has been a key technology...... for increased energy efficiency. Additional technologies suitable for small-scale networks are heat pumps, solar panels and local biomass in the form of straw or biogas. For large-scale urban networks, incineration of urban waste and geothermal heat are key technologies. With heat storages district heating...... infrastructure can contribute significantly to balancing the intermittency of wind power. This paper is an update of the authors' article published in Energy Policy in 2003 focusing on the European directives focusing on competition in the electricity and gas network industries and promotion of renewables...

  18. Union County - La Grande, Oregon geothermal district heating: feasibility assessment. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, H. II; Giddings, M.; Hanson, P.

    1982-09-01

    This report presents an assessment of geothermal district heating in the City of La Grande, Oregon. Eight study area districts were analyzed to determine their economic feasibility. Results from the analyses conclude that certain districts within the City of La Grande are economically feasible if certain assumptions are correct. Development of geothermal district heating for these areas would provide direct energy and dollar savings to the building owners and would also provide direct and indirect benefits to low and moderate income households within the City.

  19. ORC for electricity production in district heating plants. Experience of biomass fired boilers with electricity production based on ORC; ORC foer elproduktion i vaermeverk. Erfarenheter fraan biobraensleeldade pannor med ORC-baserad elproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, Barbara

    2007-12-15

    The ORC (Organic Rankine Cycle) technology is an option for the production of electricity in heat production plants with steam boilers. Traditionally, the ORC technology has been used mainly in geothermal applications. However, during the last five years, it has become of interest also in bioenergy plants with electricity production in the 0,5-2 MW{sub e} range. Among others in Austria and Germany a number of plants have been installed during the first decade of the 2100th century. Today (2007), about 70 biomass based ORC plants are in operation in Europe. About 30 more plants are under installation and commissioning. In total, around 100 plants will be operating in the near future. In today's biomass fuelled ORC type CHP plants, the ORC circuit is driven by the energy in the flue gases from a biomass fuelled furnace. Via a thermal oil boiler, the energy is transferred to the ORC circuit. The ORC circuit is connected to the district heating net for cooling. Due to the fact that the ORC circuit is connected to 300 deg C flue gas, as compared to the 1990's waste water based ORC plants, an electrical yield of nearly 20% net is obtained in the ORC circuit. The overall electrical yield based on biomass is almost 16%. In the report, operational experience from a number of plants is reported. The economic advantage of the technology is discussed. In conclusion, the ORC technology is more economical than conventional steam turbine technology in the 0,5-2 MW{sub e} range. The calculated investment for a 2 MW{sub e} ORC based CHP plant is 40 kSEK/kW{sub e}, which is considerably lower than for a conventional steam turbine based CHP plant

  20. Optimal design of district heating and cooling pipe network of seawater-source heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang-li; Duanmu, Lin; Shu, Hai-wen [School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning Province 116024 (China)

    2010-01-15

    The district heating and cooling (DHC) system of a seawater-source heat pump is large system engineering. The investments and the operational cost of DHC pipe network are higher than a tradition system. Traditional design methods only satisfy the needs of the technology but dissatisfy the needs of the economy, which not only waste a mass of money but also bring problems to the operation, the maintenance and the management. So we build a least-annualized-cost global optimal mathematic model that comprises all constrict conditions. Furthermore, this model considers the variety of heating load and cooling load, the operational adjustment in different periods of the year. Genetic algorithm (GA) is used to obtain the optimal combinations of discrete diameters. Some operators of GA are selected to reduce the calculation time and obtain good calculation accuracy. This optimal method is used to the design of the DHC network of Xinghai Bay commercial district which is a real engineering. The design optimization can avoid the matter of the hydraulic unbalance of the system, enhance the running efficiency and greatly reduce the annualized-cost comparing with the traditional design method. (author)

  1. Comparative analysis of the district heating systems of two towns in Croatia and Denmark

    DEFF Research Database (Denmark)

    Čulig-Tokić, Dario; Krajačić, Goran; Doračić, Borna

    2015-01-01

    This paper compares district heating systems in Zagreb and Aalborg in order to see their similarities and differences from which conclusions are drawn on how to improve the systems. The method chosen is the comparative analysis. Data is organized and structured so to allow clear and concise...... comparison. The results of the comparative analysis show that the district heating system in Aalborg is more advanced than the district heating system in Zagreb. This advantage is prominent in aspects of supply, demand, distribution and economic spheres. Some of the possible improvements include lowering...... specific heat and water losses. Systematic replacements and refurbishments of the old network pipes are key to this. Lowering the supply and return temperatures would enable better renewable energy sources integration. The integration of renewable energy sources in district heating systems is the most...

  2. Analysis and research on promising solutions of low temperature district heating without risk of legionella

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Fog, Jette M.

    2014-01-01

    resources. The most crucial restriction for applying low temperature district heating is the worry about the breakout of legionella, which exists preferably in low temperature hot water systems. Several novel techniques such as electric tracing and flat station were investigated for such dilemma. The pros......Most regulations of domestic hot water supply temperature is around 55-60 oC, which potentially requires higher district heating temperature. However, high supply temperature of district heating causes many problems, such as the high heating loss, and obstacles for applying renewable energy...... and cons were compared in this paper. Both the energy and economy saving ratios were analysed comparing with high temperature supply scenario. Furthermore, the viability of the applications in different types of buildings for low temperature district heating (LTDH) was also discussed by using dynamic...

  3. Expieriences On Low-Temperature District Heating In Lystrup – Denmark

    DEFF Research Database (Denmark)

    Thorsen, Jan Eric; Christiansen, Christian Holm; Brand, Marek

    2011-01-01

    This paper includes main findings made during the Danish governmentally founded project “Development and Demonstration of Low-Energy District Heating for Low-Energy Buildings”, EFP2007, and the Danish governmentally founded project ”CO2-reductions in Low-Energy Buildings and Communities...... by implementing Low-temperature district heating systems. Demonstration cases in EnergyFlexHouse and Boligforeningen Ringgården” EUDP 2011. A key challenge for optimum and competitive district heating (DH) system operation is reducing heat loss in networks. Today building regulations in most countries demand...... reduction of heat consumption for individual buildings. This means ratio between net work heat loss and heat consumption in buildings will become even more important in future. To address this challenge low-temperature DH network concept is analysed and tested in real scale. This paper describes main...

  4. A transition perspective on alternatives to coal in Chinese district heating

    Directory of Open Access Journals (Sweden)

    Jingjing Zhang

    2015-06-01

    Full Text Available China accounts for half of the world’s annual coal consumption. Coal is the primary energy source for heating in urban areas, particularly in northern China. This causes significant challenges for urban air quality problems in China and greenhouse gases emissions. Urban district heating (DH systems penetration is very high in northern China. It supplies space heating to more than 80% of urban buildings in the area. Unlike the electricity and transportation sectors, the heating sector has received little attention from policy makers and researchers in China, DH systems are an enabling infrastructure which facilitates energy efficiency improvements and the use of renewable energy sources. This study explores the dynamics and possibility to expand alternative energy sources (natural gas, biomass, direct geothermal heat, ground-source heat pump, municipal waste heat, industrial waste heat for DH in China. We apply an analytical framework largely based on the multi-level perspective in socio-technical transitions theory, in which transitions are interpreted as the result of the functioning of niche, regime and landscape elements, and interactions between them. The study provides an integrated picture of the socio-technical structure and functioning of DH in China. The results show that an energy transition in Chinese DH systems has barely started. The system is characterised by stability of the coal-based DH regime, while a number of alternative niches are struggling to emerge. Among these, natural gas is the most successful example. However, at local level different niches present opportunities in terms of physical availability, economic viability and technical capacity to address changes in landscape pressures. A sustainable heat roadmap based on integrated energy planning and policy attention at the national level could be developed as one mechanism for instigating a much needed energy transition in DH in China.

  5. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  6. Particle Emissions from District Heating Units Operating on Solid Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Wierzbicka, Aneta [Lund Inst. of Technology (Sweden). Div. of Ergonomics and Aerosol Technology

    2005-06-01

    With the increasing interest in the use of biofuels for heat and energy generation there is a growing concern about emissions from their combustion. It has been shown that biofuel furnaces emit relatively high quantities of particulate matter in comparison to natural gas and light fuel oil furnaces. Majority of the emitted particulates are smaller than 10 {mu}m with high contribution of fine (<2.5 {mu}m) and submicron (<1 {mu}m) particles. These fine particles tend to be the most troublesome: in ambient air they have been associated with adverse health effects. Submicron particles are difficult to capture in the available particle removal technologies. The aim of this study was to characterise particle emissions from district heating units operating on three commonly used biofuels, namely sawdust. pellets and forest residues. Boilers were of moving grate type. with the maximum thermal output between 1 and 1.5 MW. The measurements were done after multi cyclones, the only particle removal devices installed, therefore the direct emissions to ambient air were characterised. Influence of type of the fuel and operation load on particle emissions was investigated. Furthermore, collection efficiencies of electrostatic precipitator (ESP) and flue gas condenser, used particle separation devices in 6 MW unit, were investigated. It has been shown that in all cases large amounts of fuel particles containing heavy metals are being emitted to the atmosphere, even though the studied district heating units meet the current mass concentration emission limit requirements. Total number concentration of emitted particles with aerodynamic diameter smaller than 5 {mu}m ranged from 3 to 8x10{sup 7} particles/cm{sub n}{sup 3} with the slightly higher values from combustion of forest residues. Both mass and total number concentrations were dominated by submicron particles contribution. Elements determined by Particle Induced X-rays Emission (PIXE) analysis (Z>12) contributed to 21-34 % of

  7. Master plan study - District heating Kohtla-Jaerve and Johvi municipalities. Estonia. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The main deficiencies of the district heating system in Kohtla-Jaerve, Ahtme and Johvi (Estonia) were identified as being: Inefficiency of the heat and power production plants; Lack of means for the consumers to control their consumption of energy due to the existing constant flow system; The environmental impact from heat and power production based on oil shale; Water and heat losses from the network; Low heat intensity in the Johvi area. Investigations indicate that improvement should have first priority at the Kohtla-Jaerve power plant, total investment is estimated at US D 60,3 million, of which US D 48 million are foreign costs. The cash flow will be negative in the first half of the projects lifetime. Estii Energia should be involved in the financing of the project. At the present price level, introduction of variable flow does not significantly improve the financial viability of the project, and the improvement of the district heating system might be carried out at a later stage, when the tariff has found a more stable level and the financial viability will be more significant. Implementation of new boilers in the Kohtla-Jaerve power plant. Circulating Fluidized Bed boilers, as well as electrostatic filters and estimated to reduce the environmental impact considerably. A more in depth study of the environmental impact from utilisation of oil shale should be carried out, also in order to inform possible investors of risk of investing in the oil shale industry. It will be more expensive to supply Johvi as an independent district heating system than if Johvi is supplied from Ahtme. The results arrived at are based on a range of the crucial assumptions that: the price of oil shale is expected to reach 75% of the price of coal, the sales price of electricity from plants is 62% of the consumer price, the exchange rate of the Estonian currency is kept constant to the DEM and that the inflation is Estonia will decline from 21% to 2,3% in 2005. (ARW)

  8. Characterization of selected application of biomass energy technologies and a solar district heating and cooling system

    Energy Technology Data Exchange (ETDEWEB)

    D' Alessio, Dr., Gregory J.; Blaunstein, Robert P.

    1980-09-01

    The following systems are discussed: energy self-sufficient farms, wood gasification, energy from high-yield silviculture farms, and solar district heating and cooling. System descriptions and environmental data are included for each one. (MHR)

  9. Master plan study - District heating Sillamaee municipality. Estonia. Final report. Appendices for chapter 9

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The appendices to the final report on the master plan study on district heating in the municipality in Estonia, chapter nine, gives data related to general economic assumptions for financial and economic calculations, fuel consumption, financing, prices, fuel consumption. (ARW)

  10. Cost of district heating using geothermal energy; Ist geothermische Waerme wirtschaftlich?

    Energy Technology Data Exchange (ETDEWEB)

    Oppermann, G. [GRUNEKO AG, Ingenieure fuer Energiewirtschaft, Basel (Switzerland)

    1997-12-01

    The environmental advantages of a district heating network using geothermal energy are obvious. On the other hand utilizing geothermal energy is considered to be very expensive. The goal of this paper is to compare the costs of geothermal energy with other renewable energy sources. Based on the costs of realized plants and projects the following energy sources have been analysed. Geothermal energy, water of tunnel-drainage, waste heat of a sewage disposal platn and waste wood. All plants have a district heating network. The results are a contribution to the actuel discussion about public subsiding of geothermal energy. (orig.) [Deutsch] Die oekologischen Vorteile einer geothermischen Fernwaermeversorgung sind fuer jeden, der Bohrungen in Erwaegung zieht, unschwer erkennbar. Wie steht es aber mit den Kosten einer geothermischen Nutzung? Hier beleben Horrorzahlen wie auch Wunschdenken die Diskussionen. Der Artikel beabsichtigt einen sachlichen Beitrag zu dieser Diskussion uz liefern. Konkrete Bauprojekte im Megawattbereich der GRUNEKO AG werden kostenmaessig nach gleichen Kriterien analysiert und verglichen. Auf goethermischer Seite wird ein Doublettensystem und eine Tunnelwasserwaermenutzung kostenmaessig analysiert. Als Quervergleich werden ebenfalls GRUNEKO-Projekte mit regenerierbaren Energietraegern herangezogen (Holzschnitzelanlage, Klaeranlagenabwaerme, Seewasser-Abkuehlung). Alle Analgen haben Waermeverteilnetze. Die nachgewiesenen Kostendifferenzen zwischen Geothermie und anderen regenerativen Waermversorgungen koennten einen Beitrag leisten zu der gegenwaertig aktuellen `Ueberpruefung staatlicher Foerderungsmassnahmen zugunsten einer verstaerkten Nutzung der Geothermie`. (orig.)

  11. Biomass district heating methodology and pilot installations for public buildings groups

    Science.gov (United States)

    Chatzistougianni, N.; Giagozoglou, E.; Sentzas, K.; Karastergios, E.; Tsiamitros, D.; Stimoniaris, D.; Stomoniaris, A.; Maropoulos, S.

    2016-11-01

    The objective of the paper is to show how locally available biomass can support a small-scale district heating system of public buildings, especially when taking into account energy audit in-situ measurements and energy efficiency improvement measures. The step-by-step methodology is presented, including the research for local biomass availability, the thermal needs study and the study for the biomass district heating system, with and without energy efficiency improvement measures.

  12. Master plan study - District heating Kohtla-Jaerve and Johvi municipalities. Estonia. Final report. Appendices for chapter 8

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The appendices to chapter 8 of the final report on the master plan study on district heating in the municipalities of Kohtla-Jarve and Johvi (Estonia) presents technical data with the emphasis on district heating pipes, heat losses, prices, retrofitting, economics, costs and heat load duration. (ARW)

  13. Design of serially connected ammonia-water hybrid absorption-compression heat pumps for district heating with the utilisation of a geothermal heat source

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Ommen, Torben Schmidt; Markussen, Wiebke Brix;

    2016-01-01

    District heating (DH) can reduce the primary energy consumption in urban areas with significant heat demands. The design of a serially connected ammonia-water hybrid absorption-compression heat pump system was investigated for operation in the Greater Copenhagen DH network in Denmark, in order...... to supply 7.2 MW heat at 85 °C utilizing a geothermal heat source at 73 °C. Both the heat source and heat sink experience a large temperature change over the heat transfer process, of which a significant part may be achieved by direct heat exchange. First a generic study with a simple representation...

  14. Performance of low-temperature district heating for low-energy houses

    DEFF Research Database (Denmark)

    Brand, Marek; Dalla Rosa, Alessandro; Svendsen, Svend

    2010-01-01

    houses, which was previously developed and reported in the project “Development and demonstration of low-energy district heating for low energy housing” [EFP, 2007]. Two different concepts of low energy district heating substations are tested, and measurements of their performance aim to document...... that LEDH is a proper solution for sustainable heating systems and answer the question which concept of used substations is more favourable to be used in detached low energy houses. The preliminary results show that LEDH can provide low energy buildings with space heating and domestic hot water (DHW...

  15. The potential to supply low temperature district heating to existing building area

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    2013-01-01

    Low-temperature district heating (LTDH) has the advantages as reduced network heat loss, improved quality match between energy supply and energy demand, and increased utilization of low-grade waste heat and renewable energy. The LTDH represents the next generation district heating (DH) system....... The use of LTDH for low energy buildings was demonstrated through pilot projects carried out in Denmark. However, the majority of the buildings were built during the time when there had little requirement for building energy conservation. In order to implement the LTDH in a large scale, its feasibility...

  16. Cooperation within the district heating industry; Zusammenarbeit in der Fernwaermebranche. Wirtschaftliche und sichere Versorgung mit Fernwaerme

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, H. [Arbeitsgemeinschaft fuer Waerme und Heizkraftwirtschaft - AGFW - e.V., Frankfurt am Main (Germany)

    2003-05-01

    Safeguarding the know-how, to define the minimum requirements, to sensitise the business partner to reach a sufficient product quality and a fair order processing are the basic elements for a future-oriented business cooperation. To define the minimum requirements for the German district heating industry, the German District Heating Association (AGFW) has developed a set of regulations (AGFW-regulations). In the connection it was very important to regulate only the minimum requirements, which are defined, adopted and above all realised by all players in the district heating industry. The aim is to offer the customer the product district heat with the least effort, in the claimed quality, with acceptable prices and with a moderate revenue for the district heat company. This is the basis for an economic and secure district heat supply. (orig.) [German] Know-how-Sicherung, Definition der Mindestanforderungen, Sensibilisierung der Partner fuer ein ausreichendes Qualitaetsniveau und faire partnerschaftliche Auftragsabwicklung sind die Grundlagen einer zukunftsorientierten Zusammenarbeit. Die Definition der technischen Mindestanforderungen erfolgt fuer die Fernwaermebranche im AGFW-Regelwerk. Hierbei ist es wichtig darauf zu achten, dass nur die Mindestanforderungen festgeschrieben werden, die im Konsens zwischen allen Akteuren der Branche definiert, akzeptiert und vor allem im Rahmen der Standardisierung umgesetzt werden. (orig.)

  17. Evaluation of integration of solar energy into the district heating system of the city of Velika Gorica

    Directory of Open Access Journals (Sweden)

    Felipe Andreu Javier

    2016-01-01

    Full Text Available In the current situation the district heating system supplies the 32% of the total thermal consumption in the City of Velika Gorica. The main issue in the district heating system is the utilization of 14 small and distributed heat plants, each providing heat to a separate and individually disconnected heating grid. Reduction of costs and CO2 emissions can be reached with a high penetration of renewable sources. The aim of this paper is to evaluate and design the integration of a Central Solar Heating Plant with Seasonal Storage into the district heating system of the City. An economic assessment was made with a pessimistic and an optimistic prediction of the solar heat cost for ground mounted collectors and roof mounted collectors. The seasonal storage was chosen to be pit thermal energy storage; the system was modeled as a low-temperature district heating system with the real thermal demands of a district heating plant.

  18. Building an eco-effective district heating management system in a city

    Directory of Open Access Journals (Sweden)

    Gitelman Leonid

    2016-01-01

    Full Text Available The goal of making the urban environment safer amid increasing human impact adds to the importance of district heating management. The article outlines the results of a study into the problem of improving the urban environment by implementing two innovative solutions. Technological innovations imply the introduction of modern sustainable tools of reducing emissions in district heating networks, one of them being the combination of district heating and combined heat and power plants (a case study of Turin. Organizational innovations are built upon the management of demand for thermal energy that makes it possible to reduce investment in new construction and to optimize the architecture of heat load schedules for the purpose of alleviating energy and environmental pressure on the city. The authors propose formats and areas of demand side management for thermal energy and methods of offering economic incentives to program participants.

  19. Performance of ultra low temperature district heating systems with utility plant and booster heat pumps

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Thorsen, Jan Eric; Markussen, Wiebke Brix

    2017-01-01

    and power (CHP) and central heat pumps (HPs). The analysis focussed on the characteristic heat demands of newly build multi-story buildings and the results were based on the ratio of the individual demands compared to the total. It was found that the optimal return temperature was dependent on the forward...

  20. District heating rehabilitation project in Kaerdla on Hiiumaa, Estonia. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    The main objective of the project has been to assist Kaerdla Municipality with the rehabilitation of their district heating system with Danish technology, and thereby support and make it possible for the Municipality of Kaerdla to develop the district heating sector in Kaerdla and thereby also to reduce emissions of harmful gases to the environment, as well as making a much more rational and energy efficient system. The project would further on demonstrate the use of pre-insulated pipes, which are fully sealed against penetration of water as well as demonstrate the use of compact units as substations including weather compensation control systems for regulation of heat and hot tap water supply for the district heating consumers. Besides the project gives significantly decreases in energy consumption`s and in the pollution from the production of energy, the objective of the project was also to put great stress on providing technical assistance to Kaerdla DH company, in order to make them capable in operation and maintenance of the new district heating system, and also to train the local operational staff in operation of the complete district heating system. The project will have a high demonstration value towards other towns in Estonia with similar problems and configurations of their heating systems. (EG)

  1. Value analysis of district heating system with gas-fired peak load boiler in secondary network

    Institute of Scientific and Technical Information of China (English)

    郑雪晶; 穆振英

    2009-01-01

    In district heating(DH) system with gas-fired peak load regulating boiler in the secondary network,by prolonging run time of base load plants under rated condition,the mean energy efficiency could be increased. The fuels of the system,including coal and gas,would cause different environmental impacts. Meanwhile,the reliability of the heating networks would be changed because the peak load regulating boiler could work as a standby heat source. A model for assessment of heating system was established by value analysis to optimize this kind of system. Energy consumption,greenhouse gas emission,pollution emission and system reliability were selected as functional assessment indexes in the model. Weights of each function were determined by analytical hierarchy process (AHP) and experts consultation. Life cycle cost was used as the cost in the model. A real case as an example was discussed to obtain the optimal base load ratio. The result shows that the optimal base load ratio of the case is 0.77.

  2. Optimizing the District Heating Primary Network from the Perspective of Economic-Specific Pressure Loss

    Directory of Open Access Journals (Sweden)

    Haichao Wang

    2017-07-01

    Full Text Available A district heating (DH system is one of the most important components of infrastructures in cold areas. Proper DH network design should balance the initial investment and the heat distribution cost of the DH network. Currently, this design is often based on a recommended value for specific pressure loss (R = ∆P/L in the main lines. This will result in a feasible network design, but probably not be optimal in most cases. The paper develops a novel optimization model to facilitate the design by considering the initial investment in the pipes and the heat distribution costs. The model will generate all possible network scenarios consisting of different series of diameters for each pipe in the flow direction of the network. Then, the annuity on the initial investment, the heat distribution cost, and the total annual cost will be calculated for each network scenario, taking into account the uncertainties of the material prices and the yearly operating time levels. The model is applied to a sample DH network and the results indicate that the model works quite well, clearly identifying the optimal network design and demonstrating that the heat distribution cost is more important than the initial investment in DH network design.

  3. Process of optimization of district heat production by utilizing waste energy from metallurgical processes

    Science.gov (United States)

    Konovšek, Damjan; Fužir, Miran; Slatinek, Matic; Šepul, Tanja; Plesnik, Kristijan; Lečnik, Samo

    2017-07-01

    In a consortium with SIJ (Slovenian Steel Group), Metal Ravne, the local community of Ravne na Koro\\vskem and the public research Institut Jožef Stefan, with its registered office in Slovenia, Petrol Energetika, d.o.o. set up a technical and technological platform of an innovative energy case for a transition of steel industry into circular economy with a complete energy solution called »Utilization of Waste Heat from Metallurgical Processes for District Heating of Ravne na Koro\\vskem. This is the first such project designed for a useful utilization of waste heat in steel industry which uses modern technology and innovative system solutions for an integration of a smart, efficient and sustainable heating and cooling system and which shows a growth potential. This will allow the industry and cities to make energy savings, to improve the quality of air and to increase the benefits for the society we live in. On the basis of circular economy, we designed a target-oriented co-operation of economy, local community and public research institute to produce new business models where end consumers are put into the centre. This innovation opens the door for steel industry and local community to a joint aim that is a transition into efficient low-carbon energy systems which are based on involvement of natural local conditions, renewable energy sources, the use of waste heat and with respect for the principles of sustainable development.

  4. Heat supply to low energy dwellings in district heating areas. Analyses of CO{sub 2} emissions and electricity supply security; Varmeforsyning til lavenergiboliger i omraader med fjernvarmekonsesjon. Analyser av CO{sub 2}-utslipp og forsyningssikkerhet for elektrisitet

    Energy Technology Data Exchange (ETDEWEB)

    Thyholt, Marit

    2006-07-01

    Building low energy dwellings in large development projects is a new situation in Norway. The municipalities have to a little extent analyzed the consequences of this new housing standard with respect to the energy supply to such areas, and how this standard may change the plans for new or extended district heat production. In the provision about the mandatory connection to district heating plants, and the appendant provision related to a heating system that can utilize district heat, the district heat supply and the heat demand are not seen in connection. The objective of this dissertation is to provide the municipalities with a basis for decision making in the processing of applications concerning dispensation from the mandatory connection or the heating system requirement for dwellings with low heat demand. This basis for decision making is based on the national aim of reducing carbon dioxide (CO{sub 2}) emissions and of improving the electricity supply security. This summary provides an abstract from the discussion of the legislation as an incentive or barrier for building low energy dwellings. An abstract from a survey among construction firms concerning the motivation for building low energy dwellings is also included. In addition, the summary provides a comprehensive abstract of the results from the CO{sub 2} emission calculations, and the basis for these calculations. Introductorily a brief background of the national focus on energy savings and increased use of hydronic heating, including district heat, is given.

  5. Current and future prospects for heat recovery from waste in European district heating systems: A literature and data review

    DEFF Research Database (Denmark)

    Persson, Urban; Münster, Marie

    2016-01-01

    Municipal solid waste has seen increasing annual volumes for many decades in contemporary Europe and constitutes, if not properly managed, an environmental problem due to local pollution and greenhouse gas emissions. From an energy perspective, waste is also an alternative fuel for power and heat...... heat distribution infrastructures, without which no large-scale recovery and utilisation of excess heat is possible. In this paper, which aims to estimate municipal solid waste volumes available for heat recovery in European district heating systems in 2030, a literature and data review is performed...

  6. Modelling the Size of Seasonal Thermal Storage in the Solar District Heating System

    Directory of Open Access Journals (Sweden)

    Giedrė Streckienė

    2012-12-01

    Full Text Available The integration of a thermal storage system into the solar heating system enables to increase the use of solar thermal energy in buildings and allows avoiding the mismatch between consumers’ demand and heat production in time. The paper presents modelling a seasonal thermal storage tank various sizes of which have been analyzed in the district solar heating system that could cover a part of heat demand for the district of individual houses in Vilnius. A biomass boiler house, as an additional heat source, should allow covering the remaining heat demand. energyPRO software is used for system modelling. The paper evaluates heat demand, climate conditions and technical characteristics.Article in Lithuanian

  7. Modeling Transient Heat Transfer in Small-Size Twin Pipes for End-User Connections to Low-Energy District Heating Networks

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro; Li, Hongwei; Svendsen, Svend

    2013-01-01

    of district heating branch pipes in low-temperature operation (supply temperature 50-55°C and return temperature 20-25°C). We looked at state-of-the-art district heating branch pipes, suitable for the connection of a typical single-family house to a substation equipped with a heat exchanger for domestic hot...... water preparation. Experimental measurements of the supply temperature profiles at the outlet of the pipe, i.e. at the inlet to the substation, were compared with detailed simulations based on the finite volume (FV) method. A programming code was developed to model these profiles, and this was validated...... change of the inlet temperature and where there was a sinusoidal inlet temperature profile. The model could be used for the development of improved substation concepts and enhanced control strategies....

  8. Determination of Optimum Network Layout for Low-Energy District Heating Systems with Different Substation Types

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2011-01-01

    In this paper three different District Heating (DH) network types, which comprise substations with storage tank, and with instantaneous heat exchanger (each for domestic hot water production); and booster pumps installed in the beginning of each street at the latter network type, are pointed out...

  9. Master plan study - District heating Sillamaee municipality. Estonia. Final report. Appendices for chapter 7

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The appendices to the final report on the master plan study on the cogenerating district heating system in the municipality of Sillamae (Estonia) gives technical and costs data on existing conditions and on possible new facilities. The data relates to energy output, the energy budget, heat load duration curves, and to suggestions for improvement. (ARW)

  10. Master plan study - District heating Sillamaee municipality. Estonia. Final report. Appendices for chapter 8

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    These appendices to the master plan study on district heating in the municipality of Sillamae (Estonia) present data referring to technology assessment with the emphasis on pipes, degree days, load duration curves, cost tables, heat losses, temperature gradients, maintenance and renovation costs. (ARW)

  11. Low-temperature water reactor for the district heating atomic power plant

    Energy Technology Data Exchange (ETDEWEB)

    Skvortsov, S.A.; Sokolov, I.N.; Krauze, L.V.; Nikiporetz, Yu.G.; Philimonov, Y.V.

    1978-04-01

    A natural convection low-pressure water reactor can be utilized as a source of district heating. This provides inherent safety factors under conditions requiring emergency core cooling. The reactor pressure vessel is contained within a prestressed concrete shell, both of which are designed to withstand accident overpressure. This also results in a relatively thin-walled reactor vessel that can be fabricated on-site. The overall safety and economy of such a system merits further consideration as a system for providing low-temperature nuclear heat for district heating.

  12. Space heating with ultra-low-temperature district heating - A case study of four single-family houses from the 1980s

    DEFF Research Database (Denmark)

    Østergaard, Dorte Skaarup; Svendsen, Svend

    District heating is predicted to play a large role in the future fossil free energy system. Apart from providing energy savings by utilizing surplus heat, the district heating system also provides flexibility to fluctuating electricity generation by bridging the electricity and the heating sector...... of the year. The houses were heated by the existing hydraulic radiator systems, while domestic hot water was prepared by use of district heating and electric boosting. This paper evaluated the heating system temperatures that were necessary in order to maintain thermal comfort in four of the houses. First...... the four houses were modelled in the building simulation tool IDA ICE. The simulation models included the actual radiator sizes and the models were used to simulate the expected thermal comfort in the houses and resulting district heating return temperatures. Secondly measurements of the actual district...

  13. Assessment of existing and prospective piping technology for district-heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Oliker, I.

    1979-09-01

    Data on design features and operational experience of 40 hot water and steam district-heating networks with an overall heat capacity of 18,000 MWt have been collected, systematized, and analyzed. Piping networks located in Canada, Denmark, Finland, France, Italy, Japan, Netherlands, Sweden, USA, USSR, and West Germany have been analyzed and the data assembled. The data bank and analysis of the operational experience design features of hot water and steam district-heating networks are provided in Sections 2 and 3. In Section 4 the piping installation design is optimized in order to reduce costs wherever possible, without jeopardizing overall system efficiency, reliability or service life, and employing a mixture of typical US and European district-heating practices. The status of prospective non-metallic piping materials is presented in Section 5. The following materials have been investigated: fiberglass reinforced plastic, cross-linked polyethylene, polybutylene, prestressed concrete, polymer concrete, and asbestos-cement piping. (MCW)

  14. Improved operation of district heating consumer installations using a self-learning district heating meter. Preliminary project; Driftsoptimering af fjernvarmebrugerinstallationer vha. selvlaerende fjernvarmemaaler. Forprojekt

    Energy Technology Data Exchange (ETDEWEB)

    Drysdale, A.

    2001-12-01

    In brief, the aim of the project has been to develop a 'self-learning' district heating meter that, after being trained with operational data from a consumer installation, can effectuate optimal control of the installation. As this is judged to be a difficult task for traditional control techniques, a control method based on the use of a neural network has been used. In the project two different neural network solutions have been developed: 1) NN (or NN controller) which is a pure neural network solution consisting of two nets. The nets are trained for predicting the overall demands (NN predictor) and for implementing the best-suited control strategy (NN controller) respectively; 2) NNPIFF (or NNPIFF controller) which combines the NN controller with other control mechanisms. These are a room model, a radiator model, a PI controller and two 'feed-forward' controllers compensating for changes in outdoor temperature and the effects of passive solar heating. The NN solution is based on controlling flow, while NNPIFF is based on controlling heat (this gives the possibility for feed-forward control and thus the of compensating for the effects of passive solar heating and changing outdoor temperatures). The conclusions from this preliminary project are that: 1) The initial results from testing the NN-controller with simulated data were very encouraging. This indicates that neural networks can be used to control heating systems and as a result of this achieve energy savings; 2) Field tests with the MAK controller in a test installation have shown that the PI controller is capable of regulating the meter-valve combination. Whilst the PI-controller is operative, the NN controller is 'rained behind the scenes'. The advantage of this form of operation is that training can take place without affecting the users' comfort. However, the results from the field test have also shown that training of the NN controller has not been sufficient for it

  15. District heating and cooling system for communities through power plant retrofit and distribution network. Final report, Phase I

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    The technical and economic feasibility of retrofitting thermal power plants in Minnesota to accommodate both heat and power generation for district heating was examined and is discussed. Three communities were identified as viable sites for co-generation district heating. (LCL)

  16. Mapping Extreme Heat Vulnerability and Health Outcomes to inform the District of Columbia's Climate Adaptation Plan

    Science.gov (United States)

    Declet-Barreto, J.; Wilhelmi, O.; Goggans, A.

    2016-12-01

    In this collaborative engagement, scientists are partnering with the District of Columbia (DC) to develop an extreme heat vulnerability assessment. To do so, we map socio-demographic and built environment indicators of extreme heat vulnerability in Census Tracts in DC neighborhoods. In order to provide information useful for DC public health and urban planning practitioners, we aggregate the indicators into an index of extreme heat vulnerability. We compare the index against heat-related call data from DC's 911 system to better understand the socio-spatial distribution of extreme heat-related health outcomes. Our assessment can help inform the District's Climate Adaptation Plan as well as increase public engagement in reducing vulnerability to extreme heat.

  17. Design of Low-Energy District Heating System for a Settlement with Low-Energy Buildings

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2011-01-01

    velocity and/or max pressure gradient. Since traditional dimensioning methods cause over-dimensioned network, special attention has to be given to lower the dimensions and as a consequence heat loss from the DH network further. In this investigation pipe dimensioning method of low-energy DH system......With the integration of new low-energy buildings the traditional district heating (DH) systems with high operating temperatures will have significantly higher heat loss according to the heat supplied to the district. The relatively higher heat loss could be reduced with low operating temperatures...... was developed with an optimization method in the objective of minimizing heat loss from the network while pressure drop values were kept as the constraints through the DH network. In the dimensioning method also descending pipe dimensions were formed in the branched type DH network by taking into account...

  18. District heating and cogeneration in the EU-28: Current situation, potential and proposed energy strategy for its generalisation

    Directory of Open Access Journals (Sweden)

    Enrique Rosales-Asensio

    2016-10-01

    Full Text Available Yearly, EU-28 conventional thermal generating plants reject a greater amount of energy than what ultimately is utilised by residential and commercial loads for heating and hot water. If this waste heat were to be used through district heating networks, given a previous energy valorisation, there would be a noticeable decrease in imported fossil fuels for heating. As a consequence, benefits in the form of an energy efficiency increase, an energy security improvement, and a minimisation of emitted greenhouse gases would occur. Given that it is not expected for heat demand to decrease significantly in the medium term, district heating networks show the greatest potential for the development of cogeneration. However, to make this happen, some barriers that are far from being technological but are mostly institutional and financial need to be removed. The purpose of this review is to provide information on the potential of using waste heat from conventional thermal power plants (subsequently converted into cogeneration plants in district heating networks located in the EU-28. For this, a preliminary assessment is conducted in order to show an estimate of the cost of adopting an energy strategy in which district heating networks are a major player of the energy mix. From this assessment, it is possible to see that even though the energy strategy proposed in this paper, which is based on a dramatic increase in the joint use of district heating networks and cogeneration, is capital-intensive and would require an annual investment of roughly 300 billion euros, its adoption would result in a reduction of yearly fuel expenses in the order of 100 billion euros and a shortening of about 15% of the total final energy consumption, which makes it of paramount interest as an enabler of the legal basis of the “Secure, Clean and Efficient Energy” future enacted by the EU-28 Horizon 2020.

  19. District Heating Network Design and Configuration Optimization with Genetic Algorithm

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    2011-01-01

    the heating plant location is allowed to vary. The connection between the heat generation plant and the end users can be represented with mixed integer and the pipe friction and heat loss formulations are non-linear. In order to find the optimal DH distribution pipeline configuration, the genetic algorithm...

  20. PREDICTIVE CONTROL SYSTEM SYNTHESIS OF DISTRICT HEATING SYSTEM

    Directory of Open Access Journals (Sweden)

    Dobrotin S.A.

    2011-08-01

    Full Text Available A combined system of building heating predictive control has been synthesized in the research. Following algorithms are described: adaptive algorithm of very short-term temperature forecast and algorithm of anticipatory control of heat supply to building heating taking into account different outside climate influence on elevations of a building.

  1. District Heating Network Design and Configuration Optimization with Genetic Algorithm

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    2011-01-01

    the heating plant location is allowed to vary. The connection between the heat generation plant and the end users can be represented with mixed integer and the pipe friction and heat loss formulations are non-linear. In order to find the optimal DH distribution pipeline configuration, the genetic algorithm...

  2. Feasibility and Supply Analysis of U.S. Geothermal District Heating and Cooling System

    Science.gov (United States)

    He, Xiaoning

    Geothermal energy is a globally distributed sustainable energy with the advantages of a stable base load energy production with a high capacity factor and zero SOx, CO, and particulates emissions. It can provide a potential solution to the depletion of fossil fuels and air pollution problems. The geothermal district heating and cooling system is one of the most common applications of geothermal energy, and consists of geothermal wells to provide hot water from a fractured geothermal reservoir, a surface energy distribution system for hot water transmission, and heating/cooling facilities to provide water and space heating as well as air conditioning for residential and commercial buildings. To gain wider recognition for the geothermal district heating and cooling (GDHC) system, the potential to develop such a system was evaluated in the western United States, and in the state of West Virginia. The geothermal resources were categorized into identified hydrothermal resources, undiscovered hydrothermal resources, near hydrothermal enhanced geothermal system (EGS), and deep EGS. Reservoir characteristics of the first three categories were estimated individually, and their thermal potential calculated. A cost model for such a system was developed for technical performance and economic analysis at each geothermally active location. A supply curve for the system was then developed, establishing the quantity and the cost of potential geothermal energy which can be used for the GDHC system. A West Virginia University (WVU) case study was performed to compare the competiveness of a geothermal energy system to the current steam based system. An Aspen Plus model was created to simulate the year-round campus heating and cooling scenario. Five cases of varying water flow rates and temperatures were simulated to find the lowest levelized cost of heat (LCOH) for the WVU case study. The model was then used to derive a levelized cost of heat as a function of the population density

  3. Modelling and multi-scenario analysis for electric heat tracing system combined with low temperature district heating for domestic hot water supply

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    . In this study, electric heat tracing system was investigated as a solution to this dilemma. A model of electric heat tracing system for multi-storey buildings was built. Various pipe materials and insulation thicknesses as the parameters of the model were compared to make a comprehensive study. The performance......Low temperature district heating (LTDH) is a cost-efficient way of supplying space heating and domestic hot water (DHW) for buildings in urban areas. However, there is concern that the potential hygiene problems (Legionella) might occur if LTDH is implemented, especially for large buildings...... of the electric heating tracing system with LTDH was simulated by taking the user pattern into account. A smart control method based on thermostatic and real-time control was developed, and compared with normal control method. The impact of user pattern was tested by applying standard, stochastic, and real load...

  4. Testing, development and demonstration of large scale solar district heating systems

    DEFF Research Database (Denmark)

    Furbo, Simon; Fan, Jianhua; Perers, Bengt

    2015-01-01

    In 2013-2014 the project “Testing, development and demonstration of large scale solar district heating systems” was carried out within the Sino-Danish Renewable Energy Development Programme, the so called RED programme jointly developed by the Chinese and Danish governments. In the project Danish...... know how on solar heating plants and solar heating test technology have been transferred from Denmark to China, large solar heating systems have been promoted in China, test capabilities on solar collectors and large scale solar heating systems have been improved in China and Danish-Chinese cooperation...

  5. Integration of large-scale heat pumps in the district heating systems of Greater Copenhagen

    DEFF Research Database (Denmark)

    Bach, Bjarne; Werling, Jesper; Ommen, Torben Schmidt

    2016-01-01

    . The analysis was based on using the energy model Balmorel to determine the optimum dispatch of HPs in the system. The potential heat sources in Copenhagen for use in HPs were determined based on data related to temperatures, flows, and hydrography at different locations, while respecting technical constraints...

  6. Comparison of two solution ways of district heating control: Using analysis methods, using artificial intelligence methods

    Energy Technology Data Exchange (ETDEWEB)

    Balate, J.; Sysala, T. [Technical Univ., Zlin (Czech Republic). Dept. of Automation and Control Technology

    1997-12-31

    The District Heating Systems - DHS (Centralized Heat Supply Systems - CHSS) are being developed in large cities in accordance with their growth. The systems are formed by enlarging networks of heat distribution to consumers and at the same time they interconnect the heat sources gradually built. The heat is distributed to the consumers through the circular networks, that are supplied by several cooperating heat sources, that means by power and heating plants and heating plants. The complicated process of heat production technology and supply requires the system approach when solving the concept of automatized control. The paper deals with comparison of the solution way using the analysis methods and using the artificial intelligence methods. (orig.)

  7. Optimal dimensioning of low-energy district heating networks with operational planning

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2012-01-01

    Low-temperature operation in low-energy District Heating (DH) systems is rewarding for increased exploitation of low-temperature renewable energy sources, heightened efficiency at heat extraction, and intensified energy efficiency at heat distribution. Success of heat delivery in low......-temperature operation such as 55 °C in terms of supply and 25 °C in terms of return was achieved through real cases located at Lystrup in Denmark, and “Greenwatt Way” project located at Scotland in UK as demonstration of low-energy DH systems being considered to supply heat to new houses with low-energy class. In our...... former study the performance of in-house heating systems was investigated for changing levels of supply temperature with consideration given both to current high-heat demand and future low-heat demand value of an existing settlement. The over-dimensions obtained at in-house heating systems originally...

  8. Excess heat production of future net zero energy buildings within district heating areas in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    2012-01-01

    Denmark’s long-term energy goal is to develop an energy system solely based on renewable energy sources by 2050. To reach this goal, energy savings in buildings is essential. Therefore, the focus on energy efficient measures in buildings and netzeroenergybuildings (NZEBs) has increased. Most...... buildings in Denmark are connected to electricity grids and around half are connected to districtheating (DH) systems. Connecting buildings to larger energy systems enables them to send and receive energy from these systems. This paper’s objective is to examine how excess heat production from NZEBs...... excess heat production from solar thermal collectors. The main findings are that the excess heat from NZEBs can benefit DH systems by decreasing the production from production units utilizing combustible fuels. In DH areas where the heat demand in summer months is already covered by renewable energy...

  9. Annual emissions and air-quality impacts of an urban area district-heating system: Boston case study

    Energy Technology Data Exchange (ETDEWEB)

    Bernow, S.S.; McAnulty, D.R.; Buchsbaum, S.; Levine, E.

    1980-02-01

    A district-heating system, based on thermal energy from power plants retrofitted to operate in the cogeneration mode, is expected to improve local air quality. This possibility has been examined by comparing the emissions of five major atmospheric pollutants, i.e., particulates, sulfur oxides, carbon monoxide, hydrocarbons, and nitrogen oxides, from the existing heating and electric system in the City of Boston with those from a proposed district heating system. Detailed, spatial distribution of existing heating load and fuel mix is developed to specify emissions associated with existing heating systems. Actual electric-power-plant parameters and generation for the base year are specified. Additional plant fuel consumption and emissions resulting from cogeneration operation have been estimated. Six alternative fuel-emissions-control scenarios are considered. The average annual ground-level concentrations of sulfur oxides are calculated using a modified form of the EPA's Climatological Dispersion Model. This report describes the methodology, the results and their implications, and the areas for extended investigation. The initial results confirm expectations. Average sulfur oxides concentrations at various points within and near the city drop by up to 85% in the existing fuels scenarios and by 95% in scenarios in which different fuels and more-stringent emissions controls at the plants are used. These reductions are relative to concentrations caused by fuel combustion for heating and large commercial and industrial process uses within the city and Boston Edison Co. electric generation.

  10. Multifunctional absorption technology in district heating systems; Absorptionsteknik med multifunktion i fjaerrvaermesystem

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Viktoria; Setterwall, Fredrik

    2010-05-15

    Within the framework of the IEA's implementing agreement on heat pumping technologies, a state-of-the-art assessment of absorption technology was presented the year 2000. There, barriers for increased implementation of absorption technology were pointed out as being the high investment cost, as well as lack of knowledge with engineers and other actors. The project presented herein has analyzed the situation ten years later, with a wide scope of using the absorption technology - from ice to steam production in a district energy system. The overall aim of the presented project is to provide new knowledge on the technical and economical possibilities of integrating multiple function absorption technology in district energy systems. Also, new knowledge on important design parameters for practical and cost-effective design is given, for example the influence of temperatures (heat source as well as heat sink) and desired COP. A combination of renewed state-of-the-art assessment and new calculations has been used to reach this goal. The state-of-the-art assessment show that the increased focus on combined heat and power (CHP) for resource-efficient energy conversion go hand in hand with an increased interest in thermally driven cooling (TDC) technology. This project has identified the following to be specifically district energy adapted in absorption cooling: - design for low return temperature of the heat carrier leaving the generator part - design for 'high enough' COP maintained at part load for heat source temperatures as low as 70 deg C. - cost minimization by optimal sizing of heat exchanger surfaces for district energy design criteria (as opposed to accepting 'off-the-shelf' designs intended for higher operating temperatures). The overall analysis and findings regarding trigeneration concludes that: a. a holistic view of the production of power, heat and cold should be adopted when considering absorption technology in district energy

  11. Geothermal district heating and cooling of hotel/casinos in downtown Reno, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Cerci, Y.; Kanoglu, M.; Cengel, Y.A.; Turner, R.H. [Univ. of Nevada, Reno, NV (United States)

    1996-12-31

    In this paper, potential revenues from the proposed geothermal district heating/cooling system for the hotel/casino complexes in downtown Reno, Nevada are estimated by analyzing their actual electricity and natural gas bills during 1993 through 1994. The geothermal system appears to be feasible, and financially very attractive. The geothermal district system can meet the entire heating and cooling requirements of the hotel/casinos, generating total potential revenues of $3,486,000 per year. Also, other buildings around the downtown area such as Saint Mary`s Hospital, several motels, business complexes, Washoe County School District Building, and even the UNR campus will add extra potential revenues, if these buildings are connected to the geothermal grid. Since most buildings around the downtown use central heating and cooling system, the retrofit costs for the both system should be minimal.

  12. Decision support for optimal location of local heat source for small district heating system on the example of biogas plant

    Directory of Open Access Journals (Sweden)

    Ciapała Bartłomiej

    2017-01-01

    Full Text Available Developing a new district heating system requires making decisions affecting entire range of following activities and wellness of the system. The article presents methodics of choosing optimal location and crucial customers with three approaches to optimisation process, discuss obtained results and obstacles. Further improvements and potential applications are named.

  13. External Corrosion of Pipes in District Heating Systems; Utvaendig korrosion paa fjaerrvaermeroer

    Energy Technology Data Exchange (ETDEWEB)

    Sund, Goeran [Det Norske Veritas, Stockholm (Sweden)

    2002-07-01

    Corrosion damages of pipes in district heating systems can occur both external and internal. The aim with this work has been to clarify external corrosion damages of pipes, and try to correlate the damages to the corrosivity of different soils and waters. For the analysis the Swedish District Heating Association's district heating system statistics has been used. The district heating system statistics shows that the cost for corrosion damages is high, and pipes older than 20 years have increased risk for corrosion. The knowledge about corrosion concerning steel poles and water pipes in soils can not be applied to external corrosion of steel pipes in district heating systems. The corrosion rate of steel poles in soils is low. The corrosion of steel pipes in district heating systems can locally give high rates, up to 0,5 mm/year. The mechanism for this type of corrosion is different compared to the corrosion mechanism of poles in soils. The temperature is higher and aggressive water, with road-salt and chloride content, falls in drops on the steel pipe, and impurities evaporate on the steel surface. These factors increase the corrosion rate. If the material thickness is 5 mm, fracture can occur in the pipe within ten years. The number of copper pipe corrosion damage is limited. The most determining corrosion factors of copper pipes are pH-value and impurities as chloride and sulphate in the water. Stainless steel pipes of type 304 can not be used in soils due to the risk of local corrosion. Higher alloyed stainless steels, with molybdenum and higher chromium content should be used. It is concluded that failures can occur due to external corrosion of steel pipes. This failure is expensive and can lead to human damage. One way to eliminate failures of steel pipes is to carry out risk analysis.

  14. EFFECTS OF IMPLEMENTATION OF CO-GENERATION IN THE DISTRICT HEATING SYSTEM OF THE FACULTY OF MECHANICAL ENGINEERING IN NIŠ

    Directory of Open Access Journals (Sweden)

    Mladen M Stojiljković

    2010-01-01

    Full Text Available Implementation of co-generation of thermal and electrical energy in district heating systems often results with higher overall energy efficiency of the systems, primary energy savings and environmental benefits. Financial results depend on number of parameters, some of which are very difficult to predict. After introduction of feed-in tariffs for generation of electrical energy in Serbia, better conditions for implementation of co-generation are created, although in district heating systems barriers are still present. In this paper, possibilities and effects of implementation of natural gas fired co-generation engines are examined and presented for the boiler house that is a part of the district heating system owned and operated by the Faculty of Mechanical Engineering in Niš. At the moment, in this boiler house only thermal energy is produced. The boilers are natural gas fired and often operate in low part load regimes. The plant is working only during the heating season. For estimation of effects of implementation of co-generation, referent values are taken from literature or are based on the results of measurements performed on site. Results are presented in the form of primary energy savings and greenhouse gasses emission reduction potentials. Financial aspects are also considered and triangle of costs is shown.

  15. Financial planning for district heating: The Brooklyn Navy Yard project: A project report

    Energy Technology Data Exchange (ETDEWEB)

    1984-05-01

    Financial planning for the Brooklyn Navy Cogeneration and District Heating Project involved the establishment of three distinct potential markets, a determination of economic feasibility and the development of a financial structure that could accommodate the diverse social objectives of the project and the nature of the markets to be served. The Brooklyn Navy Yard (BNY) is owned by the City of New York (City) and managed by the non-profit Brooklyn Navy Yard Development Corporation for operation as an industrial park. Development of a cogeneration/district heating facility at the Navy Yard was undertaken to meet multiple community and economic development objectives.

  16. Application of an intermediate LWR for electricity production and hot-water district heating

    Energy Technology Data Exchange (ETDEWEB)

    1983-05-01

    The objective of the study is to evaluate the technical and economic feasibility of a 400 MWe Consolidated Nuclear Steam System (CNSS) for supplying district heat to the Minneapolis/St. Paul area. A total of three CNSS reactor sites, located various distances from the Minneapolis-St. Paul area load center, are evaluated. The distance from the load center is determined by the credited safety features of the plant design. Each site is also evaluated for three different hot water supply/return temperatures providing a total of nine CNSS study cases. The cost of district heat delivered to the load center is determined for each case.

  17. A life cycle evaluation of wood pellet gasification for district heating in British Columbia.

    Science.gov (United States)

    Pa, Ann; Bi, Xiaotao T; Sokhansanj, Shahab

    2011-05-01

    The replacement of natural gas combustion for district heating by wood waste and wood pellets gasification systems with or without emission control has been investigated by a streamlined LCA. While stack emissions from controlled gasification systems are lower than the applicable regulations, compared to the current base case, 12% and 133% increases are expected in the overall human health impacts for wood pellets and wood waste, respectively. With controlled gasification, external costs and GHG emission can be reduced by 35% and 82% on average, respectively. Between wood pellets and wood waste, wood pellets appear to be the better choice as it requires less primary energy and has a much lower impact on the local air quality.

  18. RESTful M2M Gateway for Remote Wireless Monitoring for District Central Heating Networks

    Directory of Open Access Journals (Sweden)

    Bo Cheng

    2014-11-01

    Full Text Available In recent years, the increased interest in energy conservation and environmental protection, combined with the development of modern communication and computer technology, has resulted in the replacement of distributed heating by central heating in urban areas. This paper proposes a Representational State Transfer (REST Machine-to-Machine (M2M gateway for wireless remote monitoring for a district central heating network. In particular, we focus on the resource-oriented RESTful M2M gateway architecture, and present an uniform devices abstraction approach based on Open Service Gateway Initiative (OSGi technology, and implement the resource mapping mechanism between resource address mapping mechanism between RESTful resources and the physical sensor devices, and present the buffer queue combined with polling method to implement the data scheduling and Quality of Service (QoS guarantee, and also give the RESTful M2M gateway open service Application Programming Interface (API set. The performance has been measured and analyzed. Finally, the conclusions and future work are presented.

  19. District heating and cooling systems for communities through power plant retrofit and distribution network. Final report. Volume I. Text

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-09-15

    An analysis was performed investigating the potential of retrofitting Detroit Edison's Conners Creek power plant to supply district heating and cooling to an area surrounding the plant and within the City of Detroit. A detailed analysis was made of the types and ages of the buildings in the service area as a basis for establishing loads. The analysis of the power plant established possible modifications to the turbines to serve the load in the area. Based upon the service area data and plant retrofit schemes, a distribution system was developed incrementally over a 20-y period. An economic analysis of the system was performed to provide cash flows and payback periods for a variety of energy costs, system costs, and escalation rates to determine the economic viability of the system analyzed. The legal and regulatory requirements required of the district heating and cooling system owner in Michigan were also analyzed to determine what conditions must be met to own and operate the system.

  20. Production of dry wood chips in connection with a district heating plant

    Directory of Open Access Journals (Sweden)

    Yrjölä Jukka

    2004-01-01

    Full Text Available Moisture and its variation in wood chips make the control of burning in small scale heating appliances difficult resulting in emissions and loss of efficiency. If the quality of wood chips would be better, i. e. dried and sieved fuel with more uniform size distribution would be avail able, the burning could be much cleaner and efficiency higher. In addition higher power out put could be obtained and the investment costs of the burning appliances would be lower. The production of sieved and dried wood chip with good quality could be accomplished in connection with a district heating plant. Then the plant would make profit, in addition to the district heat, from the dried wood chips sold to the neighboring buildings and enterprises sep a rated from the district heating net using wood chips in energy production. The peak power of a district heating plant is required only a short time during the coldest days of the winter. Then the excess capacity during the milder days can be used as heat source for drying of wood chips to be marketed. Then wood chips are sieved and the fuel with best quality is sold and the reject is used as fuel in the plant it self. In a larger district heating plant, quality of the fuel does not need to be so high In this paper the effect of moisture on the fuel chain and on the boiler is discussed. Energy and mass balance calculations as a tool of system design is described and the characteristics of proposed dry chips production method is discussed.

  1. Integration of heat treatment of wood with cogeneration production and district heating; Vaermebehandling av trae integrerad med kraftvaermeproduktion och fjaerrvaerme

    Energy Technology Data Exchange (ETDEWEB)

    Delin, Lennart; Essen, Henrik (AaF, Stockholm (Sweden))

    2011-05-15

    Heat treatment of wood changes the properties of wood so that the moisture uptake is reduced and the wood movements are reduced at variations in the ambient air humidity. The wood gets an increased resistance to rot and can therefore replace impregnated wood in certain applications. Heat treated wood is however not suitable for direct contact with soil. The strength is also reduced by heat treatment, so it is not recommended for supporting constructions. No additives whatsoever are used in the treatment, so the heat treated wood is very advantageous from an environmental point of view. The wood is dried completely at the heat treatment and heated to about 200 deg C. The question has hence been put, if it is advantageous to collocate a heat treatment plant with district heating or a power cogeneration plant. The aim of the study is to assess the value of such a collocation. Existing heat treatment plants are both few and small and the calculations have hence been made for how a large plant could be designed. A market study is included to assess the market for this type of plants. This shows that the present market for heat treated wood is very small. A full scale treatment plant of the type discussed in this study could probably not be built, since even single plants of this size would require a too large part of the market. The potential to replace impregnated wood is on the other hand very large. The cost for large scale heat treatment should be significantly lower than for impregnated wood and the cost for handling hazardous waste (which impregnated wood is classified as) is also removed. There should therefore be a potential for a future much larger volume of heat treated wood. The study shows that the energetic profit of collocation of a heat treatment plant for wood with district heating or power cogeneration plants is of lower importance. Maximally about 0.5 MSEK/year can be saved for a 25 000 m3/year plant. The initial drying of all sawn lumber has much more

  2. Symposium in Moscow on advanced district heating technology from the Federal Republic of Germany

    Energy Technology Data Exchange (ETDEWEB)

    Neufer, H. (Vereinigung Deutscher Elektrizitaetswerke, Frankfurt am Main (Germany, F.R.))

    1988-12-01

    Describes a symposium that took place in Moscow on 22-23 March 1983 on district heating in the FRG, covering topics such as the production of thermal power from power plants, transportation and distribution of heat and control at local thermal substations. Presentations were made by companies using district heating systems and the manufacturers of the systems such as AEG, Deutsche Babcock, Bayer AG and Siemens. Experts demonstrated that it is most probably feasible to use fuels such as gas and coal in combined processes burning them in swirl flow furnaces. A further topic was how to reduce sulfur dioxide and nitrogen oxide emissions from thermal power plants. It was demonstrated how the introduction of large heat conductors with diameters of up to 800 mm and plastic thermal insulating linings has reduced the cost and increased the speed of construction work. One direction of future research identified was the study of stresses and deformation in conductors. As the FRG already has the most comprehensive district heating system in Western Europe (producing more than 50% of its heat from coal) and thermal power losses are low and heat transfer and distribution technology is improving all the time, the main task now is to reduce costs.

  3. Istra district heating system. General technical report. Appendix 1 to the master plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-01

    The objective of the master plan project is to improve the heat supply in Istra. The considerable system losses from the fuel supplied to the end-users are one issue for improvement. At the same time, the current system operation results in poor quality heat for the consumers. Due to the inflexibility of the system the dwellings/premises of the consumers are either overheated or insufficiently heated. The financial situation in Istra, the legal ownership of the district heating system and consumers' lacking ability to pay limit the possibilities for system improvements. The Master Plan and Feasibility Study evaluates four different development scenarios. Each of the scenarios is compared to the current situation in Istra, where nothing is done to change the system, but only to operate the present system in a sustainable way. The sustainable operation of the district heating system includes all necessary renovations and component replacements necessary. The project does not take into account the present financial situation in Istra, which has resulted in less maintenance than necessary. This situation is not a comparable parameter, as it is not sustainable and will lead to a breakdown of the heat supply within a short time horizon. The General Technical Report evaluates the technical situation and describes system improvements at a general level. The intention with this report is to provide important information useful to other district heating companies in Russia. (au)

  4. Technical, economic and legal boundary conditions of district heating. Pt. 2; Technische, wirtschaftliche und rechtliche Rahmenbedingungen der Fernwaermewirtschaft. T. 2. Besondere Rechtslage

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, Norman [AGFW - Der Energieeffizienzverband fuer Waerme, Kaelte und KWK e.V., Frankfurt am Main (Germany)

    2011-04-15

    It is a common misconception that legal regulations of the electricity and gas industry can also be applied to district heating. However, the technical, economic and legal boundary conditions of district heating are quite different. The first part of this article explained the concept of district heating and analyzed its economic boundary conditions. This contribution explains the heat market and its legal boundary conditions.

  5. Influence of legislative conditioned changes in waste management on economic viability of MSW-fuelled district heating system: Case study

    Directory of Open Access Journals (Sweden)

    Tomić Tihomir

    2016-01-01

    Full Text Available District heating systems represents one of the ways by which the European Union is trying to reach set goals in energy efficiency and security field. These systems allow the use of different energy sources including local energy sources such as waste and biomass. This paper provides economic viability assessment of using these fuels in the district heating system. Economic evaluation is based on regression analysis from data of existing plants and on the locally dependent data. Some of parameters that are dependent of local parameters are price and available fuel quantity, therefore these values are separately modelled; biomass as a function of location of the plant while municipal waste as a function of location and the time changes in waste quantity and composition which depend of socio-economic trends and legislation. This methodology is applied on the case of district heating plants in the City of Zagreb where internal rates of return are calculated for four considered scenarios. Results indicate that waste powered plant can improve its profitability by co-combusting other local wastes while economic viability is achieved by introduction of region wide waste management system. Reducing plant capacity, based on prognosis of waste generation, showed that these plants can be competitive with biomass plants.

  6. Replacing critical radiators to increase the potential to use low-temperature district heating – A case study of 4 Danish single-family houses from the 1930s

    DEFF Research Database (Denmark)

    Østergaard, Dorte Skaarup; Svendsen, Svend

    2016-01-01

    radiator sizes and heating demands in 4 existing Danish single-family houses from the 1930s. A year-long dynamic simulation was performed for each of the houses to evaluate the potential to lower the heating system temperatures. The results indicate that there is a large potential to use low-temperature...... district heating in existing single-family houses. In order to obtain the full potential of low-temperature district heating, critical radiators must be replaced. Based on a novel method, a total of nine radiators were identified to be critical to ensure thermal comfort and low return temperatures in two......Low-temperature district heating is a promising technology for providing homes with energy-efficient heating in the future. However, it is of great importance to maintain thermal comfort in existing buildings when district heating temperatures are lowered. This case study evaluated the actual...

  7. Dynamic modeling of thermal conditions for hot-water district-heating net- works

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shou-jun; TIAN Mao-cheng; ZHAO You-en; GUO Min

    2014-01-01

    To investigate the dynamic characteristics of the thermal conditions of hot-water district-heating networks, a dynamic modeling method is proposed with consideration of the heat dissipations in pipes and the characteristic line method is adopted to solve it. Besides, the influences of different errors, space steps and initial values on the convergence of the dynamic model results are analyzed for a model network. Finally, a part of a certain city district-heating system is simulated and the results are compared with the actual operation data in half an hour from 6 secondary heat stations. The results indicate that the relative errors for the supply pressure and temperature in 5 stations are all within 2%, except in one station, where the relative error approaches 4%. So the proposed model and algorithm are validated.

  8. Opportunities for District Heating Systems in Ukraine. Market survey. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Brienen, M.

    2011-12-15

    The market survey should identify the existing and future opportunities for Dutch companies in the district heating sector in Ukraine, facilitate better understanding of the sector specifics by providing a complete picture on the whole district heating chain at specific cities mentioned and surrounding areas, and provide practical information on the best ways to enter this market segment by Dutch companies. The points of special interest are: (a) Analysis of main types of district heating chain in terms of the key stakeholders and their interest; Identification of the cases where the whole chain is under control (if any); Identification of the main directions of change within the existing set-up; (b) Analysis of the pricing model(s) and the procedures for setting up the prices for district heating; Identification of the main influencers on the decision making; (c) Identification of the main opportunities to use renewable energy for heating systems in Ukraine; and (d) Identification of the Dutch clusters with appropriate products, services and knowledge which can be used to achieve optimal results with district heating systems in Ukraine. Another important reason to execute this market survey is the 2g at-sign thereprogramme 'Ukraine-sustainable energy'. One of the consortia supported under the 2g at-sign there programme, is called NUSEP, Netherlands Ukrainian Sustainable Energy Platform. Under this platform 15-20 Dutch companies and institutes have joined forces. All of these companies and institutes are active in the field of(sustainable) energy. In short, the district heating sector in Ukraine offers many opportunities for Dutch companies. This survey will help Dutch companies to do business in Ukraine. The market research has been executed at both national level (where relevant concerns) and is specifically focused on the following cities and surrounding area: Kiev; Poltava; Kamyanets-Podilsky; Kovel; Lviv; Zhytomyr. Since the major developments in

  9. District Heating at Power Failures - Final Report; Fjaerrvaerme vid Elavbrott - Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Lauenburg, Patrick; Johansson, Per-Olof

    2008-11-15

    Our society is vulnerable to prolonged power cuts. In cold weather interrupted heating is one of the most serious threats. District heating is available at most locations in Sweden and if heat can be transferred to the connected buildings at a power failure, it is of great importance for securing energy supply. In this work it was found that there are good opportunities for upholding heat supply at a power failure through self-circulation in connected radiator system, which has previously been overlooked. Self Circulation occurs when there is a sufficiently large temperature difference between forward and return line in the radiator system. The control and circulation in radiator systems will fail, but if the district heating water can continue to pass through the heat exchangers of the radiator systems self-circulation can occur. A prerequisite for self-circulation in the individual buildings to work is therefore to district heating network can operate at a power failure. District heating supply must have back to maintain the production and distribution of district heating, which is not always the case. Our studies show that there is every reason to this. Moreover there are customers that have their own reserve aggregates, such as hospitals, which are dependent on the district heating network function. In an extensive power failure, it may be desirable to establish a smaller grid, separate from backbone, using local electricity generation. The establishment of such a network requires there is local production which can start to loose voltage networks and has necessary control equipment for the frequency approach. In Malmoe, it is now possible to establish a such a network with the help of local production units. A prerequisite is that there are consumption of heating. It is not unusual for power plants (which produce both electricity and heat) is dependent on the pipe system for cooling the production of electricity. One can from the results also argue that every

  10. Urban form and heat consumption, a comparative study in Copenhagen districts

    DEFF Research Database (Denmark)

    Mohammadi Dehcheshme, Mostafa; Jensen, Jesper Ole

    Since urban form and land use patterns significantly influence the cities energy needs, the study linkage of energy consumption and urban form is an interdisciplinary issue and one the current central topics of urban planners in recent years. Our concern in this paper, therefore, is to address...... the implications of urban development and form in terms of its impact on energy consumption in ten districts of Copenhagen city. As comparative study, this paper is trying to respond the question: How does urban form impact the heat consumption in households in Copenhagen districts? To respond this question, two...... models, housing level model and city level model, are presented and each model includes the part of urban form indicators. Finally in the comparative frame, the impacts of urban form indicators on heat consumption are analyzed for the Copenhagen districts....

  11. Control of district heating prices under cartel law; Die kartellrechtliche Kontrolle der Fernwaermepreise

    Energy Technology Data Exchange (ETDEWEB)

    Buedenbender, Ulrich [Technische Univ. Dresden (Germany). Lehrstuhl fuer Buergerliches Recht, Energiewirtschaft und Arbeitsrecht

    2011-07-01

    While cartel law had much to say in the electricity and gas sector during the past few years, the issue was less relevant in the district eating sector, where the latest intensive debate dates back more than 20 years. This changed in autumn 2009, when the Federal Cartel Office decided to intensify control of district heating rates according to Sect. 32 e GWB. This publication presents an analysis of all relevant questions concerning the definition of the relevant market, the situation of district heating utilities in the market, and the standards applied for a more concrete definition of the concept of misuse. Apart from an extensive and critical analysis of the statements issued so far, some practically relevant points are discussed and solved that had not come into focus so far. (orig./AKB)

  12. Design of energy-efficient buildings using interaction between Building Simulation Programme and Energy Supply Simulations for District Heating

    DEFF Research Database (Denmark)

    Christensen, Jørgen Erik; Dalla Rosa, Alessandro; Nagla, Inese

    demand density for which the connection to low-energy district heating networks is cost-effective and energy efficient. By using a dynamic energy simulation program for buildings it is possible to analyze the influence of the human behaviour for the building and link the results to the simulation program...... for district heating networks. The results show that human behaviour can lead to 50% higher heating demand and 60% higher peak loads than expected according to reference values in standardized calculation of energy demand pattern in energy-efficient buildings. The consequence is that in order to get the full...... that there is a large potential for distributing energy in areas with energy efficient buildings. As a measure for the feasibility of district heating, the linear heat density can be used as a representative value, and the results show that it is possible to supply heat with low-energy district heating networks...

  13. Production and Distribution Planning in District Heating Systems; Produktions- och distributionsplanering av fjaerrvaerme

    Energy Technology Data Exchange (ETDEWEB)

    Kvarnstroem, Johan; Dotzauer, Erik; Dahlquist, Erik

    2006-12-15

    To produce heat and power is costly. Therefore it is important for the district heating companies to plan and optimize the production. The aim with the present project is to find out how also the distribution of heat can be considered in the planning. The principal procedure is to first construct a prediction of the heat demand, and then, given the demand prediction, construct the production plan. Due to the complexity of the problem, the need for mathematical models is obvious. The report gives a survey introduction to production planning in district heating systems and presents a model for the purpose. The model is developed for one of the district heating systems in Stockholm owned by the energy company Fortum. Traditionally, models for production planning do not consider the distribution network. In such models, usually the methodology Mixed Integer Programming (MIP) is used. The report suggests how the distribution network can be modeled as a MIP; it shall be possible to link the network model to existing software that models the production plants as MIP. The model is developed in the programming language GAMS. Analysis and results are presented. The results show that the suggested plans vary depending on if the distribution network is considered or not. The report also suggests how a simple sensitivity analysis of the production plans can be performed. This is necessary since there are always uncertainties associated with weather- and load predictions.

  14. Environmental Assessment and FONSI for the Bison School District Heating Plant Project (Institutional Conservation Program [ICP]).

    Science.gov (United States)

    Department of Energy, Washington, DC.

    This paper examines the environmental impacts of replacing the Bison, South Dakota School District's elementary and high school heating system consisting of oil-fired boilers, and supporting electrical components with a new coal-fired boiler and supporting control system piping. Various alternative systems are also examined, including purchasing a…

  15. Magneto-Inductive Communication among Pumps in a District Heating System

    DEFF Research Database (Denmark)

    Afkhami Meybodi, Soroush; Pardo, Pablo; Dohler, Mischa

    2011-01-01

    Realizing distributed control for a large scale district heating plant needs a metropolitan wireless communication framework among its pumps. The main challenge at PHY layer here is coverage rather than interference. This paper reviews the potential methods and proposes the use of magnetic...

  16. Design of a low temperature district heating network with supply recirculation

    DEFF Research Database (Denmark)

    Li, Hongwei; Dalla Rosa, Alessandro; Svendsen, Svend

    2010-01-01

    The focus on continuing improving building energy efficiency and reducing building energy consumption brings the key impetus for the development of the new generation district heating (DH) system. In the new generation DH network, the supply and return temperature are designed low in order...

  17. District heating as a source of flexibility in the Nordic electricity market

    DEFF Research Database (Denmark)

    Skytte, Klaus; Sneum, Daniel Møller; Sandberg, Eli

    2016-01-01

    . District heating (DH) is an important sector in the Nordic energy system and has a large potential for increased flexible operation in relation to the future electricity system. This potential is only partly exploited today. One reason for this is the differences in regulatory framework conditions for DH...

  18. Plug and Play Process Control Applied to a District Heating System

    DEFF Research Database (Denmark)

    Knudsen, Torben; Trangbæk, Klaus; Kallesøe, Carsten Skovmose

    2008-01-01

    The general ideas within plug and play process control (PTC) are to initialize and reconfigure control systems just by plug and play. In this paper these ideas are applied to a district heating pressure control problem. First of all this serves as a concrete example of PTC, secondly some of the f...

  19. Magneto-Inductive Communication among Pumps in a District Heating System

    DEFF Research Database (Denmark)

    Afkhami Meybodi, Soroush; Pardo, Pablo; Dohler, Mischa

    2011-01-01

    Realizing distributed control for a large scale district heating plant needs a metropolitan wireless communication framework among its pumps. The main challenge at PHY layer here is coverage rather than interference. This paper reviews the potential methods and proposes the use of magnetic...

  20. Largest fluidized bed power plant unit for power and district heat supply for Berlin (Part 1)

    Energy Technology Data Exchange (ETDEWEB)

    Abroell, G.; Bade, H.; Bietz, K.H.; Jahn, P. (ABB Kraftwerke AG, Mannheim (Germany))

    1991-11-01

    The Berlin Power and Light Company (Bewag) has decided to install, on the inner city site of Moabit, for the supply of electricity and district heating, a new unit with circulating atmospheric fluidized bed combustion. The plant will be designed for a thermal capacity of 240 MW. The basis for this decision, and also the technical implementation, will be made public.

  1. Barriers for district heating as a source of flexibility for the electricity system

    DEFF Research Database (Denmark)

    Skytte, Klaus; Olsen, Ole Jess; Soysal, Emilie Rosenlund

    2017-01-01

    The Scandinavian countries Denmark, Norway and Sweden currently deploy large amounts of variable renewable energy (VRE) sources, especially wind power. This calls for additional flexibility in the power market. The right coupling to the underlying national and local district heating (DH) markets...

  2. Methodological Approach to Determining the Effect of Parallel Energy Consumption on District Heating System

    Science.gov (United States)

    Latosov, Eduard; Volkova, Anna; Siirde, Andres; Kurnitski, Jarek; Thalfeldt, Martin

    2017-05-01

    District heating (DH) offers the most effective way to enhance the efficiency of primary energy use, increasing the share of renewable energy in energy consumption and decreasing the amount of CO2 emissions. According to Article 9 section 1 of the Directive 2010/31/EU of the European Parliament and of the Council of 19 May 2010 on the energy performance of buildings, the Member states of the European Union are obligated to draw up National Plans for increasing the number of nearly zero-energy buildings [1]. Article 2 section 2 of the same Directive states that the energy used in nearly zero-energy buildings should be created covered to a very significant extent by energy from renewable sources, including energy from renewable sources produced on-site or nearby. Thus, the heat distributed by DH systems and produced by manufacturing devices located in close vicinity of the building also have to be taken into account in determining the energy consumption of the building and the share of renewable energy used in the nearly zero-energy buildings. With regard to the spreading of nearly zero-energy and zero-energy houses, the feasibility of on-site energy (heat and/or electricity) production and consumption in DH areas energy (i.e. parallel consumption, when the consumer, connected to DH system, consumes energy for heat production from other sources besides the DH system as well) needs to be examined. In order to do that, it is necessary to implement a versatile methodological approach based on the principles discussed in this article.

  3. Link between intermittent electrical energy sources and district heating sector

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo

    2016-01-01

    Energy has always been one of the key challenges in planning of societies' development worldwide. The COP conference in Paris in December 2015 has shown unprecedented mutual understanding of harmful consequences climate change can cause. Integrating power and heating sectors in an efficient way...

  4. Geothermal district heating system in Tanggu, Tianjin, China

    Energy Technology Data Exchange (ETDEWEB)

    Jinrong, C. (Government Geothermal Office of Tanggu District, Tianjin (China))

    1992-08-01

    Tanggu is a harbor and industrial area and is the location of Tianjin Harbor, Tianjin Bonded Area and Tianjin Economic Development Area. It covers an area of 859 km[sup 2] and has a population of 430,000. Tanggu Geothermal Field is located at the western coast of Bohai Sea. This area belongs to the depression area of North China geologically. Neogene strata of Guantao Group is distributed widely in this region. Good permeability, large thickness, and high conductivity make it form a regional low-temperature porous reservoir. The reservoir is buried to a depth of 1,600 - 2,100 m. The total thickness of about 500 m can be divided into upper and lower sections including three aquifers. Geothermal space heating tests of Tanggu started in 1980. Up to the present, there are a total of 16 geothermal wells in Tanggu. Thirteen of them were drilled in the shallower aquifer. The total production rate of thermal water is 3.636 x 10[sup 6] m[sup 3] annually. The net production rate used for space heating is 3.10 x 10[sup 6] m[sup 3] from 11 wells. It has heated an area of 620 x 10[sup 3] m[sup 2] and has solved winter heating for 100 thousand people.

  5. Link between intermittent electrical energy sources and district heating sector

    DEFF Research Database (Denmark)

    Dominkovic, Dominik Franjo

    2016-01-01

    Energy has always been one of the key challenges in planning of societies' development worldwide. The COP conference in Paris in December 2015 has shown unprecedented mutual understanding of harmful consequences climate change can cause. Integrating power and heating sectors in an efficient way...

  6. Large scale solar district heating. Evaluation, modelling and designing - Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.

    2000-07-01

    The appendices present the following: A) Cad-drawing of the Marstal CSHP design. B) Key values - large-scale solar heating in Denmark. C) Monitoring - a system description. D) WMO-classification of pyranometers (solarimeters). E) The computer simulation model in TRNSYS. F) Selected papers from the author. (EHS)

  7. District Heating and CHP - Local Possibilities for Global Climate Change Mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Difs, Kristina

    2010-07-01

    Global warming, in combination with increasing energy demand and higher energy prices, makes it necessary to change the energy use. To secure the energy supply and to develop sustainable societies, construction of energy-efficient systems is at the same time most vital. The aim of this thesis is therefore to identify how a local energy company, producing district heating (DH), district cooling (DC) and electricity in combined heat and power (CHP) plants, can contribute to resource-efficient energy systems and cost-effective reductions of global carbon dioxide (CO{sub 2}) emissions, along with its customers. Analyses have been performed on how a local energy company can optimise their DH and DC production and what supply-side and demand-side measures can lead to energy-efficient systems in combination with economic and climate change benefits. The energy company in focus is located in Linkoeping, Sweden. Optimisation models, such as MODEST and reMIND, have been used for analysing the energy systems. Scenario and sensitivity analyses have also been performed for evaluation of the robustness of the energy systems studied. For all analyses a European energy system perspective was applied, where a fully deregulated European electricity market with no bottlenecks or other system failures was assumed. In this thesis it is concluded that of the DH-supply technologies studied, the biomass gasification applications and the natural gas combined cycle (NGCC) CHP are the technologies with the largest global CO{sub 2} reduction potential, while the biomass-fuelled plant that only produces heat is the investment with the smallest global CO{sub 2} reduction and savings potential. However, the global CO{sub 2} reduction potential for the biomass integrated gasification combined cycle (BIGCC) CHP and NGCC CHP, the two technologies with highest electricity efficiencies, is highly dependent on the assumptions made about marginal European electricity production. Regarding the effect on

  8. Feasibility Study for the Ivano-Frankivsk District Heating Repowering: Analysis of Options

    Energy Technology Data Exchange (ETDEWEB)

    Markel, L.; Popelka, A.; Laskarevsky, V.

    2002-03-20

    Part of the U.S. Initiative on Joint Implementation with the Ukraine Inter-Ministerial Commission on Climate Change, financed by the US Department of Energy. The project was implemented by a team consisting of the US company SenTech, Inc. and the Ukrainian company Esco-West. The main objective of the effort was to assess available alternatives of Ivano-Frankivsk (I-F) District Heating repowering and provide information for I-F's investment decision process. This study provides information on positive and negative technical and economic aspects of available options. Three options were analyzed for technical merit and economic performance: 1. Installation of cogeneration system based on Gas Turbine (GT) and Heat Recovery Heat Exchanger with thermal capacity of 30 MW and electrical capacity of 13.5 MW. This Option assumes utilization of five existing boilers with total capacity of 221 MW. Existing boilers will be equipped with modern controls. Equipment in this Option was sized for longest operating hours, about 8000 based on the available summer baseload. 2. Installation of Gas Turbine Combined Cycle (GTCC) and Heat Recovery Steam Generator (HRSG) with thermal capacity 45 MW and electrical capacity of 58.7 MW. This Option assumes utilization of five existing boilers with total capacity of 221 MW. Existing boilers will be equipped with modern controls. The equipment was sized for medium, shoulder season thermal load, and some cooling was assumed during the summer operation for extension of operating hours for electricity production. 3. Retrofit of six existing boilers (NGB) with total thermal capacity of 255.9 MW by installation of modern control system and minor upgrades. This option assumes only heat production with minimum investment. The best economic performance and the largest investment cost would result from alternative GTCC. This alternative has positive Net Present Value (NPV) with discount rate lower than about 12%, and has IRR slightly above 12%. The

  9. PARAMETERS OF WATER CIRCULATION NETWORK FOR A DISTRICT HEATING AND COOLING SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In a district heating and cooling system, i.e. Beijing combined heating cooling and power (CHCP) system studied here, high temperature water generated by two cogeneration plants circulates through a network between the plants and heat substations. At heat substations, supply water of high temperature from the network drives absorption chillers for air-conditioning in summer and meets space heating demands in winter or domestic hot water demands by heat exchangers in the whole year. The parameters, i.e. supply/return water temperature in the network, has a great impact on primary energy consumption (PEC) of the absorption chillers, circulation pumps and domestic hot water (DHW), which is studied in this paper.

  10. The Development of a New District Heating Concept

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro

    of the work and lists the methods which were used. Chapter 5 explains the results of the scientific content reported in the articles in PART II. Article I introduces the technical and organizational strategies that can facilitate the establishment of a successful energy planning in a community. It analyses...... conditions with regard to the inlet temperature profile. The proposed integrated solution consisting of service pipe and heat exchanger unit with a booster pump satisfies the requirement for DHW supply within l0 seconds and achieves heat savings for 200 kWhth/yr with an additional electricity use......PART I of this doctoral thesis consists of 6 chapters. Chapter 1 summarizes the main issues caused by the use of energy resources. They involve ecological, economic, demographical and socio-political topics that are linked together and define the background of the thesis. Chapter 2 describes...

  11. Optimal Design of Cogeneration Systems in Industrial Plants Combined with District Heating/Cooling and Underground Thermal Energy Storage

    Directory of Open Access Journals (Sweden)

    Vincenzo Dovì

    2011-12-01

    Full Text Available Combined heat and power (CHP systems in both power stations and large plants are becoming one of the most important tools for reducing energy requirements and consequently the overall carbon footprint of fundamental industrial activities. While power stations employ topping cycles where the heat rejected from the cycle is supplied to domestic and industrial consumers, the plants that produce surplus heat can utilise bottoming cycles to generate electrical power. Traditionally the waste heat available at high temperatures was used to generate electrical power, whereas energy at lower temperatures was either released to the environment or used for commercial or domestic heating. However the introduction of new engines, such as the ones using the organic Rankine cycle, capable of employing condensing temperatures very close to the ambient temperature, has made the generation of electrical power at low temperatures also convenient. On the other hand, district heating is becoming more and more significant since it has been extended to include cooling in the warm months and underground storage of thermal energy to cope with variable demand. These developments imply that electric power generation and district heating/cooling may become alternative and not complementary solutions for waste energy of industrial plants. Therefore the overall energy management requires the introduction of an optimisation algorithm to select the best strategy. In this paper we propose an algorithm for the minimisation of a suitable cost function, for any given variable heat demand from commercial and domestic users, with respect to all independent variables, i.e., temperatures and flowrates of warm fluid streams leaving the plants and volume and nature of underground storage. The results of the preliminary process integration analysis based on pinch technology are used in this algorithm to provide bounds on the values of temperatures.

  12. Lowering district heating temperatures – Impact to system performance in current and future Danish energy scenarios

    DEFF Research Database (Denmark)

    Ommen, Torben; Markussen, Wiebke Brix; Elmegaard, Brian

    2016-01-01

    CHP (Combined heat and power) production in connection with DH (district heating) systems has previously demonstrated a significant reduction in primary energy consumption. With extended installation of intermittent sustainable sources, such as eg. wind turbines rather than thermal units....... Utility plants and demand curves corresponded to the current and future scenarios for the DH system of Greater Copenhagen. Performance curves from typical CHP-plant technologies were used to represent the changed operation of power and heat production for changed DH temperatures. The results show...

  13. Efficiency gains in Danish district heating. Is there anything to learn from benchmarking?

    DEFF Research Database (Denmark)

    Munksgaard, Jesper; Pade, Lise-Lotte; Fristrup, P.

    2005-01-01

    for increasing productivity in Danish district heating production and (2) to examine whether benchmarking has a role to play.Using data envelopment analysis our analyses show that by assuming variable returns to scale a potential exists to reduce production costs by 5–27% depending on the portfolio of inputs......Facing a market structure of independent heating systems and cost-of-service regulation the regulator considers ways to create incentives for increasing efficiency in heat production.One way is to implement benchmark regulation. The aim of this paper is twofold: (1) To investigate the potential...

  14. Initiative for local district heating. New chances for municipal utilities. Boundary conditions for the heat market; Initiative Nahwaerme. Neue Chancen fuer Stadtwerke. Rahmenbedingungen fuer den Waermemarkt

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, Michael [K.Group GmbH, Muenchen (Germany). Bereich Nachhaltige Energieversorgung und Stadtentwicklung

    2009-06-15

    In the regulated market, municipal utilities are forced to find new fields of activity. The heat market offers good chances. For example, local district heating grids can be established, independent power generation can be encouraged, and new services can be offered which may increase customer loyalty. The district heating initiative of the Baden-Wuerttemberg Minister of the Environment was launched early in 2009 with the intention to offer valuable assistance to the municipal utilities. (orig.)

  15. Effects of heat recovery for district heating on waste incineration health impact: a simulation study in Northern Italy.

    Science.gov (United States)

    Cordioli, Michele; Vincenzi, Simone; De Leo, Giulio A

    2013-02-01

    The construction of waste incinerators in populated areas always causes substantial public concern. Since the heat from waste combustion can be recovered to power district heating networks and allows for the switch-off of domestic boilers in urbanized areas, predictive models for health assessment should also take into account the potential benefits of abating an important source of diffuse emission. In this work, we simulated the dispersion of atmospheric pollutants from a waste incinerator under construction in Parma (Italy) into different environmental compartments and estimated the potential health effect of both criteria- (PM(10)) and micro-pollutants (PCDD/F, PAH, Cd, Hg). We analyzed two emission scenarios, one considering only the new incinerator, and the other accounting for the potential decrease in pollutant concentrations due to the activation of a district heating network. We estimated the effect of uncertainty in parameter estimation on health risk through Monte Carlo simulations. In addition, we analyzed the robustness of health risk to alternative assumptions on: a) the geographical origins of the potentially contaminated food, and b) the dietary habits of the exposed population. Our analysis showed that under the specific set of assumptions and emission scenarios explored in the present work: (i) the proposed waste incinerator plant appears to cause negligible harm to the resident population; (ii) despite the net increase in PM(10) mass balance, ground-level concentration of fine particulate matter may be curbed by the activation of an extensive district heating system powered through waste combustion heat recovery and the concurrent switch-off of domestic/industrial heating boilers. In addition, our study showed that the health risk caused by waste incineration emissions is sensitive to assumptions about the typical diet of the resident population, and the geographical origins of food production.

  16. How low can the low heating load density district heating be? Environmental aspects on low heating load density district heating of the present generation compared to a domestic oil burner; Hur vaermegles kan den vaermeglesa fjaerrvaermen vara? Miljoeaspekter paa vaermegles fjaerrvaerme med dagens teknik jaemfoerd med villaoljepanna

    Energy Technology Data Exchange (ETDEWEB)

    Froeling, Morgan [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Chemical Environmental Science

    2005-07-01

    In Sweden we can see an increase of district heating networks in residential areas with low heat density. For the customer the economy is normally the most important argument when deciding to choose district heating. For many customers, however, arguments regarding environmental friendliness are important complimentary arguments. When district heating systems are built with decreased heat density, the environmental impacts from use of district heating will increase, depending on such as increased need of pipes and increased heat losses from the distribution system. The purpose of this study is to investigate if there is a limit, a lowest heat density when it is not any longer beneficial to build district heating when district heating replaces local oil furnace heating. Life cycle inventory data for district heating distribution systems in areas with low heat density has been compared with the use of oil furnaces. The environmental impacts are categorized into Global Warming Potential, Acidification Potential, Eutrofication Potential and Use of Finite Resources. To enhance the assessment three single point indicators have also been used: EcoIndicator99, EPS and ExternE. The economics of using district heating in areas with low heat density has not been regarded in this study. A model comparing the space heating of a single family home with an oil furnace or with district heating has been created. The home has an annual heat need of 20 MWh. The district heating distribution network is characterized by its linear heat density. The linear heat density is a rough description of a district heating network, and thus also the results from the model will be general. Still it can give us a general idea of the environmental limit for district heating in areas with low heat density. An assessment of all results indicate that with the type of technology used at present it is not environmentally beneficial to use district heating with lower linear heat density than 0,2 MWh/m. At

  17. Urban form and heat consumption, a comparative study in Copenhagen districts

    DEFF Research Database (Denmark)

    Mohammadi Dehcheshme, Mostafa; Jensen, Jesper Ole

    the implications of urban development and form in terms of its impact on energy consumption in ten districts of Copenhagen city. As comparative study, this paper is trying to respond the question: How does urban form impact the heat consumption in households in Copenhagen districts? To respond this question, two......Since urban form and land use patterns significantly influence the cities energy needs, the study linkage of energy consumption and urban form is an interdisciplinary issue and one the current central topics of urban planners in recent years. Our concern in this paper, therefore, is to address...

  18. Summertime hot water comfort in houses[District heating optimization]; Varmvattenkomfort sommatid i smaahus

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Tommy [Lund Inst. of Technology (Sweden). Dept. of Heat and Power Engineering

    2002-07-01

    Problems with low domestic hot water temperature summertime in district heating systems in low heat density areas is studied. The study is based on dynamic simulation of a part of a district heating system. A part of the DH system in Malmoe, owned by Sydkraft Vaerme Malmoe AB, serves as source of inspiration for the computer model. The system in Malmoe is used as a reference system in the investigations. A number of different system configurations are regarded. For example, the influence of the following is investigated: the placing of thermostatic valves in the system, length of pipes, type of domestic hot water controller in the DH substations, degree of insulation of the pipes, pipe dimensions, supply temperature at the production site and also domestic hot water use. The different system configurations are optimized with respect to heat losses under the condition that an acceptable domestic hot water comfort must be secured. How to construct the domestic hot water controllers in order to achieve the best system performance is also studied in the report. The calculations show that regardless of if a thermostatic valve is installed only in the periphery of the DH system or in all DH substations there is an optimum set point at which the heat losses from the system is minimized. For all the system configurations studied in this project an acceptable domestic hot water temperature is secured at the optimum set point. It appears that under operation conditions where a good domestic hot water temperature cannot be attained in large parts of the system the characteristics of the DH substations will lead to high return temperatures. The high return temperatures lead to an increase in heat losses and such operation conditions cannot coincide with an optimum set point regarding heat losses from the system. For both alternatives regarding the location of the thermostatic valve(s) the optimum set point is reduced as the length of the distribution pipes is increased. In the

  19. Combined Heat and Power Dispatch Considering Heat Storage of Both Buildings and Pipelines in District Heating System for Wind Power Integration

    Directory of Open Access Journals (Sweden)

    Ping Li

    2017-06-01

    Full Text Available The strong coupling between electric power and heat supply highly restricts the electric power generation range of combined heat and power (CHP units during heating seasons. This makes the system operational flexibility very low, which leads to heavy wind power curtailment, especially in the region with a high percentage of CHP units and abundant wind power energy such as northeastern China. The heat storage capacity of pipelines and buildings of the district heating system (DHS, which already exist in the urban infrastructures, can be exploited to realize the power and heat decoupling without any additional investment. We formulate a combined heat and power dispatch model considering both the pipelines’ dynamic thermal performance (PDTP and the buildings’ thermal inertia (BTI, abbreviated as the CPB-CHPD model, emphasizing the coordinating operation between the electric power and district heating systems to break the strong coupling without impacting end users’ heat supply quality. Simulation results demonstrate that the proposed CPB-CHPD model has much better synergic benefits than the model considering only PDTP or BTI on wind power integration and total operation cost savings.

  20. Choice of insulation standard for pipe networks in 4th generation district heating systems

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Mohammadi, Soma

    2016-01-01

    and smart gas grids. Improving DH pipes by improving the insulation standard results in decreasing the heat and temperature losses from the pipe networks. When reducing heat losses from DH pipes, there is a trade-off between the increasing cost of pipe insulation and the associated savings in the heat......Reducing heat losses from the pipe networks in district heating (DH) systems is one of the main challenges when developing DH in the future. Fourth generation DH is a concept that defines the role of DH in future smart energy systems as an integrated part together with smart electricity grids...... by implementing different pipe insulation standards. In the second step, the specific grid losses found in the first step are analysed in an integrated energy systems model where all main energy sectors and their interrelations are included. The outcome of the study can provide decision support when planning...

  1. Environmental performance of Miscanthus as a fuel alternative for district heat production

    DEFF Research Database (Denmark)

    Parajuli, Ranjan; Sperling, K.; Dalgaard, Tommy

    2015-01-01

    scenarios: (i) in Combined Heat and Power (CHP) plant and (ii) in a Boiler (producing heat only). Biomass conversion to heat is also compared with the conversion of natural gas (NG). The environmental impact categories considered for the assessment are: Global Warming Potential (GWP), Non-Renewable Energy......This study discusses about the environmental performance of Miscanthus conversion to district heat. Life Cycle Impact Assessment (LCIA) is used as a tool to assess the environmental impacts related to the biomass conversion to heat. Energy conversion of Miscanthus is compared in two combustion...... that despite the biomass possessed advantage in reducing GWP and NRE use, additional land required for Miscanthus could be seen as a disadvantage....

  2. Operational Planning of Low-Energy District Heating Systems Connected to Existing Buildings

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2012-01-01

    -energy houses in a traditional DH network, the aim in this paper was given to reduce the dimensions of the low-energy DH network as much as possible. Hence, the performance analyses of the inhouse radiator heating systems equipped in existing buildings were carried out for low temperatures of supply and return......This article focuses on low-energy District Heating (DH) systems operating in low-temperatures such as 55°C in terms of supply and 25°C in terms of return in connection with existing buildings. Since the heat loss from the network has a significant impact in case of supplying heat to low....... The response of the radiator heating systems at different levels of supply temperature was used to form the operational planning of the low-energy DH system, which determined the design parameters of the low-energy DH network in terms of overall mass flow requirement and the return temperature from...

  3. Exergy analysis of the performance of low-temperature district heating system with geothermal heat pump

    Directory of Open Access Journals (Sweden)

    Sekret Robert

    2014-03-01

    Full Text Available Exergy analysis of low temperature geothermal heat plant with compressor and absorption heat pump was carried out. In these two concepts heat pumps are using geothermal water at 19.5 oC with spontaneous outflow 24 m3/h as a heat source. The research compares exergy efficiency and exergy destruction of considered systems and its components as well. For the purpose of analysis, the heating system was divided into five components: geothermal heat exchanger, heat pump, heat distribution, heat exchanger and electricity production and transportation. For considered systems the primary exergy consumption from renewable and non-renewable sources was estimated. The analysis was carried out for heat network temperature at 50/40 oC, and the quality regulation was assumed. The results of exergy analysis of the system with electrical and absorption heat pump show that exergy destruction during the whole heating season is lower for the system with electrical heat pump. The exergy efficiencies of total system are 12.8% and 11.2% for the system with electrical heat pump and absorption heat pump, respectively.

  4. Effect of Design Static Pressure Level on Energy Efficiency at Low Energy District Heating Systems

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2012-01-01

    Low-Energy District Heating (DH) systems with low-temperature operations, such as 55 °C in terms of supply and 25 °C in terms of return, were considered to be the 4th generation of the DH systems for the low-energy future with energy efficiencies focused to be achieved at newly built and existing...... buildings by the Danish building regulations. Therefore focus has been given to reduce the heat demand of the consumer site with integration of low-energy buildings, to be considered for new settlements and with renovation of existing buildings to low-energy class. The reduction of heat demand increases...... the ratio of heat loss from the DH network in comparison to the heat supplied to the district. In our former studies, the low-energy DH system was optimized with the aim of reducing the heat loss from the low-energy DH network in a certain limit of static pressure level of 10 bara. Thus, in this present...

  5. The role of district heating in decarbonising the EU energy system and a comparison with existing strategies

    DEFF Research Database (Denmark)

    Connolly, David; Lund, Henrik; Mathiesen, Brian Vad;

    2013-01-01

    Many strategies have already been proposed for the decarbonisation of the EU energy system by the year 2050. These typically focus on the expansion of renewable energy in the electricity sector and subsequently, electrifying both the heat and transport sectors as much as possible...... are identified and then, the EU27 energy system is modelled to investigate the impact of district heating. The results indicate that a combination of heat savings, district heating in urban areas, and individual heat pumps in rural areas will enable the EU27 to reach its greenhouse gas emission targets by 2050...

  6. Selected cost considerations for geothermal district heating in existing single-family residential areas

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, K.

    1996-06-01

    In the past, district heating (geothermal or conventionally fueled) has not been widely applied to the single-family residential sector. Low-heat load density is the commonly cited reason for this. Although it`s true that load density in these areas is much lower than for downtown business districts, other frequently overlooked factors may compensate for load density. In particular, costs for distribution system installation can be substantially lower in some residential areas due to a variety of factors. This reduced development cost may partially compensate for the reduced revenue resulting from low-load density. This report examines cost associated with the overall design of the system (direct or indirect system design), distribution piping installation, and customer branch lines. It concludes with a comparison of the costs for system development and the revenue from an example residential area.

  7. District heat, energy for fore-sighted people. Proceedings; Energie fuer Menschen mit Weitblick. Vortragsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The proceedings volume contains a great part of the papers presented, but some are represented only by copies of the overheads which accompanied the papers. The lecture meeting was devoted to the following major topics: Economical and safe supply of district heat, outlook on the future of the district heat supply industry in a liberalized market, customer relationship management taking into account contracting, information and communication via call centers, and other forms of guidance for decision making.(GL) [German] Vortraege vorliegend teils als Manuskript, teils als Folien mit folgenden Schwerpunkten: Die wirtschaftliche und sichere Versorgung durch Fernwaerme, die Zukunft der Fernwaerme im liberalisierten Markt, der Weg zum Kunden im Hinblick auf Contracting, Kommunikation, Betreuung sowie Beratung und Entscheidungsfindung.(GL)

  8. Demand for waste as fuel in the swedish district heating sector: a production function approach.

    Science.gov (United States)

    Furtenback, Orjan

    2009-01-01

    This paper evaluates inter-fuel substitution in the Swedish district heating industry by analyzing almost all the district heating plants in Sweden in the period 1989-2003, specifically those plants incinerating waste. A multi-output plant-specific production function is estimated using panel data methods. A procedure for weighting the elasticities of factor demand to produce a single matrix for the whole industry is introduced. The price of waste is assumed to increase in response to the energy and CO2 tax on waste-to-energy incineration that was introduced in Sweden on 1 July 2006. Analysis of the plants involved in waste incineration indicates that an increase in the net price of waste by 10% is likely to reduce the demand for waste by 4.2%, and increase the demand for bio-fuels, fossil fuels, other fuels and electricity by 5.5%, 6.0%, 6.0% and 6.0%, respectively.

  9. Introduction of renewable energy sources in the district heating system of Greece

    Directory of Open Access Journals (Sweden)

    Nikolaos Margaritis

    2016-06-01

    Full Text Available The district heating (DH system of Greece, mainly supported from lignite fired stations, is facing lately significant challenges. Stricter emission limits, decreased efficiency due to old age and increased costs are major challenges of the lignite sector and are expected to result in the decommissioning of several lignite-fired units in the coming years. As a result, managers of DH networks are currently investigating alternative scenarios for the substitution of thermal power that it is expected to be lost, through the integration of Renewable Energy Sources (RES into the system. In this paper, the DH systems of Kozani and Ptolemaida are examined regarding possible introduction of RES. The first study examines district heating of Kozani and alternative future options for covering a part of city’s thermal load whereas the second study refers to a biomass CHP plant (ORC technology, 1MWe, 5MWth to be powered from a biomass mixture (wood chips and straw.

  10. Supply of domestic hot Water at comfortable temperatures by low-temperature district heating without risk of Legionella

    OpenAIRE

    Yang, Xiaochen; Svendsen, Svend; Li, Hongwei

    2016-01-01

    In Denmark, about 25% of the primary energy is consumed for covering the heat demand in the buildings. To achieve a complete renewable energy system by 2050, which is the goal set by the Danish government, methods that are more efficient and economical for heat supply are urgently needed. Considering the overall energy efficiency and environment effect, the district heating (DH) is a cost-effective way of supplying heat to high heat density area. Currently, the DH system in most countries are...

  11. Economic Assessment of Rural District Heating by Bio-Steam Supplied by a Paper Mill in Canada

    Science.gov (United States)

    Marinova, Mariya; Beaudry, Catherine; Taoussi, Abdelaziz; Trepanier, Martin; Paris, Jean

    2008-01-01

    The article investigates the feasibility of district heating in a small town adjacent to a Kraft pulp mill in eastern Canada. A detailed heat demand analysis is performed for all buildings using a geographical information system and archived data provided by the municipality. The study shows that the entire space heating requirement of the town…

  12. Heating and Domestic Hot Water Systems in Buildings Supplied by Low-Temperature District Heating

    DEFF Research Database (Denmark)

    Brand, Marek

    , because less heat is sold to customers and there is higher heat loss in the network. Similarly, higher connection power than needed means bigger pipe diameters are needed, resulting in higher heat losses as well. Using realistic values is therefore very important for feasibility calculations of DH.  ...

  13. Effects of boosting the supply temperature on pipe dimensions of low-energy district heating networks

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2015-01-01

    This paper presents a method for the dimensioning of the low-energy District Heating (DH) piping networks operating with a control philosophy of supplying heat in low-temperature such as 55 °C in supply and 25°C in return regularly while the supply temperature levels are being boosted in cold...... winter periods. The performance of the existing radiators that were formerly sized with over-dimensions was analyzed, its results being used as input data for the performance evaluation of the piping network of the low-energy DH system operating with the control philosophy in question. The optimization...

  14. On-line corrosion monitoring in geothermal district heating systems. I. General corrosion rates

    DEFF Research Database (Denmark)

    Richter, S.; Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.

    2006-01-01

    General corrosion rates in the geothermal district heating systems in Iceland are generally low, of the magnitude 1 mu m/y. The reason is high pH (9.5), low-conductivity (200 mu m/y) and negligible dissolved oxygen. The geothermal hot water is either used directly from source or to heat up cold...... ground water. The fluid naturally contains sulphide, which helps keeping the fluid oxygen-free but complicates the electrochemical environment. In this research on-line techniques for corrosion monitoring were tested and evaluated in this medium. Electrochemical methods worked well as long as frequency...

  15. Costs of urban area retrofit to district heating and cooling systems: north-central cities

    Energy Technology Data Exchange (ETDEWEB)

    Santini, D J; Davis, A A; Marder, S M

    1978-03-01

    This study considers the major urbanized areas of six U.S. cities (Washington, D.C.; St. Louis; Cleveland; Milwaukee; Detroit; Chicago) to arrive at reasonably accurate estimates of costs required to retrofit them with district heating and cooling systems. Only costs associated with heating and hot water are addressed here. Demand estimates and energy-supply analyses are made, and component capital costs are estimated to arrive at annualized system costs. Finally, a comparison of alternative energy-delivery options is made, and estimates of scarce-fuel savings are derived. 39 refs., 12 figs., 14 tables.

  16. Regulatory Barriers for Flexible Coupling of the Nordic Power and District Heating Markets

    DEFF Research Database (Denmark)

    Skytte, Klaus; Olsen, Ole Jess

    2016-01-01

    that the choice of technologies for heat generation is mainly driven by outdated policies and tax conditions that create barriers for additional flexibility in the overall energy system. However, the balancing markets may be a main driver for introducing more electric boilers into DH and thereby increase its......Large share of variable renewable energy sources (VRE) is being deployed in the Nordic countries, especially wind power. This calls for additional flexibility of the power market. With the right coupling to the underlying national and local district heating (DH) markets, large shares of flexibility...

  17. Application of service oriented architecture for sensors and actuators in district heating substations.

    Science.gov (United States)

    Gustafsson, Jonas; Kyusakov, Rumen; Mäkitaavola, Henrik; Delsing, Jerker

    2014-08-21

    Hardwired sensor installations using proprietary protocols found in today's district heating substations limit the potential usability of the sensors in and around the substations. If sensor resources can be shared and re-used in a variety of applications, the cost of sensors and installation can be reduced, and their functionality and operability can be increased. In this paper, we present a new concept of district heating substation control and monitoring, where a service oriented architecture (SOA) is deployed in a wireless sensor network (WSN), which is integrated with the substation. IP-networking is exclusively used from sensor to server; hence, no middleware is needed for Internet integration. Further, by enabling thousands of sensors with SOA capabilities, a System of Systems approach can be applied. The results of this paper show that it is possible to utilize SOA solutions with heavily resource-constrained embedded devices in contexts where the real-time constrains are limited, such as in a district heating substation.

  18. Development and demonstration of low-energy district heating for low-energy buildings. Main report and appendices; Udvikling og demonstration af lavenergifjernvarme til lavenergibyggeri. Hovedrapport + bilag

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, C.H.; Paulsen, O.; Boehm, B. (Teknologisk Institut, Taastrup (Denmark)); Thorsen, J.E. (Danfoss A/S, (Denmark)); Ting Larsen, C.; Jepsen, B.K. (LOGSTOR A/S, (Denmark)); Kaarup Olsen, P.; Lambertsen, H.; Hummelshoej, R. (COWI A/S, (Denmark)); Svendsen, Svend; Fan, J.; Furbo, S. (DTU-BYG, Kgs. Lyngby (Denmark)); Worm, J.; Didriksen, J. (Energitjenesten, Copenhagen (Denmark))

    2009-03-15

    The project describes a design concept for district heating supply of low energy houses based on 24 hour equalizing of load and very low district heating flow temperatures. District heating is a very flexible system in terms of utilizing waste heat from CHPplants, refuse incineration and industrial processes as well as renewable energy sources in an energy efficient manner. However, in relation to district heating for low energy houses there are some challenges according to investment costs and costs related to heat loss from distribution network. The objective of the project is to develop a design concept that will reduce these costs and be a 'de facto' standard of district heating to low energy houses. The design concept is based on a new type of consumer station with a domestic hot water plate heat exchanger connected to a tank on the district heating primary side. To specify design and operating parameters a simulation model of the consumer station was developed in TRNSYS. Different parameters were investigated e.g. tank size (60-200 liter) and charge flow (120-14 kg/h). An area of 92 single family houses classified as 'class 1' (42.6 kWh/m2) according to the Danish Building Regulation was chosen as reference area. Hydraulic and thermal analysis in the calculation tool TERMIS were used to lay out the distribution network based on pre-insulated twinpipes (supply and return in same casing pipe) with low-lambda PUR insulation and diffusion barrier. The design concept is compared with 3 other types of district heating systems. For a traditional system with single pipes and high district heating temperatures, the heat loss of the distribution network is calculated to 36%. In comparison, the distribution loss of the design concept can be as low as 12%. The total investment costs are almost equal for the 4 systems. In the new design concept, the cost of distribution network is reduced due to the use of smaller dimensions and twin-pipes. Though, the

  19. Development and demonstration of low-energy district heating for low-energy buildings. Main report and appendices; Udvikling og demonstration af lavenergifjernvarme til lavenergibyggeri. Hovedrapport + bilag

    Energy Technology Data Exchange (ETDEWEB)

    Christiansen, C.H.; Paulsen, O.; Boehm, B. (Teknologisk Institut, Taastrup (Denmark)); Thorsen, J.E. (Danfoss A/S, (Denmark)); Ting Larsen, C.; Jepsen, B.K. (LOGSTOR A/S, (Denmark)); Kaarup Olsen, P.; Lambertsen, H.; Hummelshoej, R. (COWI A/S, (Denmark)); Svendsen, Svend; Fan, J.; Furbo, S. (DTU-BYG, Kgs. Lyngby (Denmark)); Worm, J.; Didriksen, J. (Energitjenesten, Copenhagen (Denmark))

    2009-03-15

    The project describes a design concept for district heating supply of low energy houses based on 24 hour equalizing of load and very low district heating flow temperatures. District heating is a very flexible system in terms of utilizing waste heat from CHPplants, refuse incineration and industrial processes as well as renewable energy sources in an energy efficient manner. However, in relation to district heating for low energy houses there are some challenges according to investment costs and costs related to heat loss from distribution network. The objective of the project is to develop a design concept that will reduce these costs and be a 'de facto' standard of district heating to low energy houses. The design concept is based on a new type of consumer station with a domestic hot water plate heat exchanger connected to a tank on the district heating primary side. To specify design and operating parameters a simulation model of the consumer station was developed in TRNSYS. Different parameters were investigated e.g. tank size (60-200 liter) and charge flow (120-14 kg/h). An area of 92 single family houses classified as 'class 1' (42.6 kWh/m2) according to the Danish Building Regulation was chosen as reference area. Hydraulic and thermal analysis in the calculation tool TERMIS were used to lay out the distribution network based on pre-insulated twinpipes (supply and return in same casing pipe) with low-lambda PUR insulation and diffusion barrier. The design concept is compared with 3 other types of district heating systems. For a traditional system with single pipes and high district heating temperatures, the heat loss of the distribution network is calculated to 36%. In comparison, the distribution loss of the design concept can be as low as 12%. The total investment costs are almost equal for the 4 systems. In the new design concept, the cost of distribution network is reduced due to the use of smaller dimensions and twin-pipes. Though, the

  20. Solar assisted district heating system Hanover-Kronsberg; Solar unterstuetzte Nahwaermeversorgung Hannover-Kronsberg

    Energy Technology Data Exchange (ETDEWEB)

    Schlosser, M.; Heuer, M.; Bodmann, M.; Fisch, M.N. [Technische Univ. Braunschweig (DE). Inst. fuer Gebaeude- und Solartechnik (IGS)

    2006-07-01

    Since mid-2000, the Hanover-Kronsberg pilot plant has been providing heat for 106 apartments in multiple dwellings. A solar collector system and a seasonal hot-water heat store are integrated in the plant. Auxiliary heat is provided by the district heating system of the Kronsberg development. Collector yields in the first year were below expectations. Leaky connections between the collector field and supply mains resulted in standstills and loss of profit. In 2004, all connections were replaced successively, and the hydraulic system of the collector circuit was modified. The performance data of the last few years are the basis of this contribution, which focuses on the experience with the collector system since its commissioning. (orig.)

  1. Heat Mismatch of future Net Zero Energy Buildings within district heating areas in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    The long-term goal for Denmark is to develop an energy system solely based on renewable energy sources (RES) in 2050. To reach this goal energy savings in buildings are essential. Therefore, a focus on energy efficient measures in buildings and net zero energy buildings (NZEBs) have increased...... systems enables them to send or receive energy from these systems. This is beneficial for NZEBs because even though they have an annual net exchange of zero, there is a temporal mismatch in regard to the energy consumption of buildings and the production from the renewable energy units added to them...... instead of wasting the energy. The objective in this paper is find how large an area of NZEBs is to be built within DH areas and how the heat mismatch of NZEBs influence different types of Danish DH systems. In the analyses nine different scenarios are analyzed. The examination is from a technical...

  2. Numerical evaluation of plate heat exchanger performance in geothermal district heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, T. [Iceland Univ., Reykjavik (Iceland)

    1996-12-31

    This paper describes the performance of plate heat exchangers in residential water radiator heating systems receiving their heat from geothermal resources. Radiator theory is reviewed and determination of annual hot water requirements for space heating is discussed. Performance evaluation is made of plate heat exchangers and results obtained by means of two equations commonly used for this purpose, the Sieder-Tate and the Dittus-Boelter equations, compared to results obtained with a simplified equation where heat transfer in the heat exchanger is assumed to depend only on the fluid mass flow on both sides. It is found that for prevailing temperature ranges in Icelandic geothermal systems the mass pow approximation gives results very close to those determined by the more complicated conventional equations. (UK)

  3. Master plan study - District heating Kohtla-Jaerve and Johvi municipalities. Estonia. Final report. Appendices for chapter 7

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The appendices to chapter 7 of the master plan study on district heating in the municipalities of Kohtla-Jarve and Johvi (Estonia) present technical data on production units, also with regard to new facilities. (ARW)

  4. Operational experiences with the waste heat boilers of the gas and steam installation in the district heating power station Dresden-Nossener Bruecke; Betriebserfahrungen mit den Abhitzekesseln der GuD-Anlage im HKW Dresden-Nossener Bruecke

    Energy Technology Data Exchange (ETDEWEB)

    Busch, F. [DREWAG, Dresden (Germany); Klauke, F. [BBP ENERGY, Oberhausen (Germany)

    2001-07-01

    Today, Dresden is covering just under half of the total heat requirements by district heating, 95% of which come from heating and refuse incineration and heating power stations. The location of the new gas-cycle power station at the intersection of the big long-distance heating lines is near the centre of the town. The district heating power station Dresden-Nossener Bruecke was conceived for base-load operation and, thanks to its flexible design, is capable of supplying the city's networks with about 85% of its requirements of electric energy and district heating in gas and steam operation. For an adequate supply with a high rate of fuel utilization the waste-heat boilers were designed in such a way as to be usable in five different operating modes. (orig.) [German] Dresden deckt heute knapp die Haelfte des gesamten Waermebedarfs durch Fernwaerme, die zu 95% aus Heiz- und Muell-Heizkraftwerken stammt. Der Standort der neuen GuD-Anlage am Knotenpunkt der grossen Fernwaermeleitungen liegt zentrumsnah. Das Heizkraftwerk Dresden-Nossener Bruecke wurde fuer den Grundlastbetrieb konzipiert und ist dank flexibler Auslegung in der Lage, die Stadtnetze mit rund 85% ihres Elektroenergie- und Fernwaermebedarfs im GuD-Betrieb zu versorgen. Zur leistungsgerechten Versorgung mit hohem Brennstoffnutzungsgrad wurden die Abhitzekessel so ausgestattet, dass sie in fuenf verschiedenen Betriebsarten einsetzbar sind. (orig.)

  5. Biomass District Heat System for Interior Rural Alaska Villages

    Energy Technology Data Exchange (ETDEWEB)

    Wall, William A.; Parker, Charles R.

    2014-09-01

    Alaska Village Initiatives (AVI) from the outset of the project had a goal of developing an integrated village approach to biomass in Rural Alaskan villages. A successful biomass project had to be ecologically, socially/culturally and economically viable and sustainable. Although many agencies were supportive of biomass programs in villages none had the capacity to deal effectively with developing all of the tools necessary to build a complete integrated program. AVI had a sharp learning curve as well. By the end of the project with all the completed tasks, AVI developed the tools and understanding to connect all of the dots of an integrated village based program. These included initially developing a feasibility model that created the capacity to optimize a biomass system in a village. AVI intent was to develop all aspects or components of a fully integrated biomass program for a village. This meant understand the forest resource and developing a sustainable harvest system that included the “right sized” harvest equipment for the scale of the project. Developing a training program for harvesting and managing the forest for regeneration. Making sure the type, quality, and delivery system matched the needs of the type of boiler or boilers to be installed. AVI intended for each biomass program to be of the scale that would create jobs and a sustainable business.

  6. Exergy performance analysis of the conceptual district energy network system with heat pump

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Seung Won; Chung, Ha Seung [Hongik University, Seoul (Korea, Republic of); Kim, Min Sung [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2014-08-15

    To increase the efficiency of a district heating system, we propose a district energy network concept which combines several heating resources with additional electric heat pump and thermal energy storage. With help of thermal energy storage, a heat pump can be operated at maximum efficiency at all the time. Electricity generated with less CO{sub 2} emission makes the proposed system much more environmentally friendly. Even though the proposed concept can be applied to any given situation, a specific target area was chosen to show the effectiveness of the newly proposed energy network concept more clearly. Several constraints were applied for the selection process and a simplified model used for quantitative comparison between the existing and the developed concept. Exergy analysis showed the increased performance of proposed energy network system. The result showed that the newly proposed concept generates less CO{sub 2} emission by 46% at maximum compared to the existing system. By using additional renewable energy sources, we can reduce CO{sub 2} emission even further.

  7. Identifying the optimal supply temperature in district heating networks - A modelling approach

    DEFF Research Database (Denmark)

    Mohammadi, Soma; Bojesen, Carsten

    2014-01-01

    of this study is to develop a model for thermo-hydraulic calculation of low temperature DH system. The modelling is performed with emphasis on transient heat transfer in pipe networks. The pseudo-dynamic approach is adopted to model the District Heating Network [DHN] behaviour which estimates the temperature...... dynamically while the flow and pressure are calculated on the basis of steady state conditions. The implicit finite element method is applied to simulate the transient temperature behaviour in the network. Pipe network heat losses, pressure drop in the network and return temperature to the plant...... are calculated in the developed model. The model will serve eventually as a basis to find out the optimal supply temperature in an existing DHN in later work. The modelling results are used as decision support for existing DHN; proposing possible modifications to operate at optimal supply temperature....

  8. Environmental considerations for geothermal energy as a source for district heating

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, Kevin D.

    1996-01-01

    Geothermal energy currently provides a stable and environmentally attractive heat source for approximately 20 district heating (DH) systems in the United States. The use of this resource eliminates nearly 100% of the conventional fuel consumption (and, hence, the emissions) of the loads served by these systems. As a result, geothermal DH systems can rightfully claim the title of the most fuel-efficient CH systems in operations today. The cost of producing heat from a geothermal resource (including capitalization of the production facility and cost for pumping) amounts to an average of $1.00 per mission Btu (0.0034 $/kWh). The major environmental challenge for geothermal systems is proper management of the producing aquifer. Many systems are moving toward injection of the geothermal fluids to ensure long-term production.

  9. Reduction of pumping energy losses in district heating and cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    Zakin, J.L.

    1991-12-01

    This project was designed to explore the effects of different structures of cationic surfactant drag reducing additives on their efficiency and on their effective temperature ranges. The goal was to develop surfactant systems that would be useful in the appropriate temperature ranges for district heating systems (50--110{degree}C) and for district cooling systems (2--20{degree}C). To this end the chemical compositions of quaternary annonium salts and of counter-ions were varied. More than twenty different commercial or semi commercial quarterly ammonium salts from US suppliers and two from a German supplier (Hoechst) were tested along with thirty five different counter-ions. In addition, blends of several of each were also tested. A further object of this project was to check the compatibility of surfactant drag reducers with commercial or semi-commercial corrosion inhibitors in regard to maintaining their drag reducing ability and corrosion inhibiting capability.

  10. Reduction of pumping energy losses in district heating and cooling systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Zakin, J.L.

    1991-12-01

    This project was designed to explore the effects of different structures of cationic surfactant drag reducing additives on their efficiency and on their effective temperature ranges. The goal was to develop surfactant systems that would be useful in the appropriate temperature ranges for district heating systems (50--110{degree}C) and for district cooling systems (2--20{degree}C). To this end the chemical compositions of quaternary annonium salts and of counter-ions were varied. More than twenty different commercial or semi commercial quarterly ammonium salts from US suppliers and two from a German supplier (Hoechst) were tested along with thirty five different counter-ions. In addition, blends of several of each were also tested. A further object of this project was to check the compatibility of surfactant drag reducers with commercial or semi-commercial corrosion inhibitors in regard to maintaining their drag reducing ability and corrosion inhibiting capability.

  11. A Direct Heat Exchanger Unit used for Domestic Hot Water Supply in a Single-family House Supplied by Low Energy District Heating

    DEFF Research Database (Denmark)

    Brand, Marek; Thorsen, Jan Eric; Svendsen, Svend

    2010-01-01

    on the testing of the dynamic behaviour of an Instantaneous Heat Exchanger Unit(IHEU) designed for DHW heating and space heating in detached family houses supplied by LEDH ensuring an entry-to-substation temperature of 51 °C. We measured the time it takes for the IHEU to produce DHW with a temperature of 42 °C......The increasing number of new and renovated buildings with reduced heating requirements will soon make traditional District Heating (DH) systems uneconomic. To keep DH competitive in the future, the heat loss in DH networks needs to be reduced. One option is to reduce the supply temperature of DH...... as much as possible. This requires a review of the behaviour of the whole domestic hot water (DHW) supply system with focus on the user comfort and overall costs. This paper describes some practical approaches to the implementation of this Low Energy District Heating (LEDH) concept. It reports...

  12. Enablers and barriers to evidence based planning in the district health system in Uganda; perceptions of district health managers.

    Science.gov (United States)

    Henriksson, Dorcus Kiwanuka; Ayebare, Florence; Waiswa, Peter; Peterson, Stefan Swartling; Tumushabe, Elly K; Fredriksson, Mio

    2017-02-02

    The District Health System was endorsed as the key strategy to achieve 'Health for all' during the WHO organized inter-regional meeting in Harare in 1987. Many expectations were put upon the district health system, including planning. Although planning should be evidence based to prioritize activities, in Uganda it has been described as occurring more by chance than by choice. The role of planning is entrusted to the district health managers with support from the Ministry of Health and other stakeholders, but there is limited knowledge on the district health manager's capacity to carry out evidence-based planning. The aim of this study was to determine the barriers and enablers to evidence-based planning at the district level. This qualitative study collected data through key informant interviews with district managers from two purposefully selected districts in Uganda that have been implementing evidence-based planning. A deductive process of thematic analysis was used to classify responses within themes. There were considerable differences between the districts in regard to the barriers and enablers for evidence-based planning. Variations could be attributed to specific contextual and environmental differences such as human resource levels, date of establishment of the district, funding and the sociopolitical environment. The perceived lack of local decision space coupled with the perception that the politicians had all the power while having limited knowledge on evidence-based planning was considered an important barrier. There is a need to review the mandate of the district managers to make decisions in the planning process and the range of decision space available within the district health system. Given the important role elected officials play in a decentralized system a concerted effort should be made to increase their knowledge on evidence-based planning and the district health system as a whole.

  13. Application of vacuum steam systems to hot water district heating and cooling systems; Phase 2, System design and installation: Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-01-01

    Pequod Associates, Inc. and District Energy St. Paul, Inc. installed a pilot project of an innovative District Heating technology through a contract with the US Department of Energy: Application of Vacuum Steam Systems to Hot Water District Heating and Cooling Systems FG01-88CE26560. This applied research was funded by the Energy Research and Development Act (94-163) for District Heating and Cooling Research. The Department of Energy recognizes the importance of developing low-cost conversion techniques for hot water district heating systems. The experimental design is an intervention technique that permits hot water district heating systems to connect to buildings equipped with steam heating systems. This method can substantially reduce conversion cost in many older buildings. The method circulates moist hot air as a heating medium under atmospheric and vacuum conditions in standard steam radiators and steam heating coils. The system operates with heat exchangers and blower/receiver package. The pilot project involved the installation of such a system in an office building located at 310 Cedar Street, St. Paul, Minnesota. The installation enabled District Energy to provide service to a building that otherwise could not be converted to district heating without major system renovations. If the operating results of the pilot project are favorable, the technology cab be adopted by many district heating systems to lower conversion costs and increase market penetration. Among the additional benefits from this technology are eliminating old, inefficient boilers, lower maintenance costs and improved fuel efficiency.

  14. The strategic role of district heating in renewable energy use; Die strategische Bedeutung der Nahwaerme zur Nutzung erneuerbarer Energien

    Energy Technology Data Exchange (ETDEWEB)

    Nast, M. [Deutsches Zentrum fuer Luft- und Raumfahrt e.V. (DLR), Stuttgart (Germany). Abt. Systemanalyse und Technikbewertung; Boehnisch, H. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany)

    1998-02-01

    District heating allows the utilization of biomass in low emission heating plants, the exploitation of solar energy and the seasonal storage of heat. If a sustainable energy supply system is to be created, district heating must not only be the system of choice for new housing districts but must also be retrofitted in existing settlements. The detailed analysis of a rural community shows that large segments of existing buildings can be connected to district heating systems even in regions with predominantly single dwellings and rural housing densities. The conditions necessary for establishing district heating systems are discussed. (orig.) [Deutsch] Nahwaermesysteme ermoeglichen, fossile und biogene Brennstoffe einzusetzen und lassen sich an saisonale Waermespeicher anschliessen. Zum Aufbau einer nachhaltigen Energieversorgung ist Nahwaerme nicht nur in Neubaugebieten notwendig sondern muss auch in den schon laenger genutzten Gebaeudebestand integriert werden. Das Beispiel einer umfassend analysierten Landgemeinde zeigt, dass ein grosser Teil des bestehenden Gebaeudebestandes an Waermenetze angeschlossen werden kann, selbst bei vorherrschender Bebauung mit Einfamilienhaeusern und laendlichen Gebaeudedichten. Die notwendigen Rahmenbedingungen fuer den Aufbau einer Nahwaermeversorgung werden erlaeutert. (orig.)

  15. District Heating using a gas-motor-driven heat pump - result checking; Erfolgskontrolle. Heizzentrale mit indirekter Gasmotor-Waermepumpe. Berufsschulen Bern-Lorraine

    Energy Technology Data Exchange (ETDEWEB)

    Eggen, B.; Lanz, S.

    2003-07-01

    This final report for the Swiss Federal Office of Energy presents the results of a project that evaluated the operation of a district heating scheme that supplies various school and college buildings, residential buildings and Berne's Botanical Gardens with heat. This pilot and demonstration system comprises an indirect gas motor heat pump with co-generation unit and an electrically-driven heat pump. In order to achieve a high performance ratio the co-generation unit was additionally equipped with a heat-recovery heat pump which condenses the waste gas and recovers radiation heat losses. The implementation of the district heating project was done in stages to meet annual heat demands of around 6'500 MWh. About 50% of these demands are met by the indirect gas motor heat pump. Figures are presented on the optimisation of heat utilisation from ground water which permitted an improvement in the total efficiency of the plant of around 30% compared with a conventional installation. The authors state that, with this installation, it could be demonstrated in an exemplary fashion that heat pumps can also be installed in existing, non-renovated buildings. In the planning of such heat pump systems they recommend that special attention be paid to the overall performance ratio, and that the rate of flow of the heat source and system temperatures be taken into account.

  16. A simple quasi-dynamic model of a district heating system used for operational optimization

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Benny

    1998-12-01

    Equivalent models of DH (District Heating) systems are being developed and verified. The models will be used for operational optimization of DH systems. By nature this requires transient models of the DH network, however, some insight can be gained even from a steady state model of the DH network demonstrating the importance of the many parameters which are needed in the models. The temperature level as well as the line heat demand is low in Danish DH systems compared to many foreign DH systems. It has been advocated that the supply temperature should always be kept as low as possible in order to minimize the operational costs. However, this is not true in all cases as the optimum operational strategy will minimize the sum of the heat loss cost and the pumping cost. Thus in case of high line heat demands the supply temperature should not always be kept as low as possible. It has been shown that a simple model, i.e. one pipe - one bypass - one house, can be used for operational optimization, both in the steady state and in the transient case. What remains to be shown is how well this simple model can represent a whole district heating system. The optimization was carried out with matlab routines and with the high number of simulations performed, the computing time is rather long. Even, though much work has already been done, it is still not perfectly clear which demands must be put on simulation and optimization time steps in order to achieve a reliable solution without too much computational effort. (LN)

  17. Background of the feasibility study of geothermal district heating in Tianjin

    Energy Technology Data Exchange (ETDEWEB)

    Yao, S.K.

    1983-01-01

    Tianjin is the largest user of low-temperature geothermal energy in China. It has been selected by the state as the model for the development and direct utilization of geothermal energy. There are 259 geothermal wells in the city, 75 of these are run by Tianjin Utility to supply water to residents and industrial users. The domestic, industrial, and agricultural uses of geothermal water are discussed. A drop in the level of the hot water has led to the building of a central district heating system and a plan for future exploitation of wells that are of higher temperature in areas outside the city.

  18. Institutional and financial guide to geothermal district heating, serial no. 2

    Science.gov (United States)

    1982-03-01

    General planning considerations which affect nearly every community are reviewed, and alternative operating structures which are available to communities are reviewed, including local governments, nonprofit cooperatives, private enterprises, and joint ventures. The financing options available to publicly-owned and privately-owned district heating systems are then summarized. The geothermal production and distribution activities most appropriate to each type of operating structure are reviewed, along with typical equity and debt funding sources. The tax advantages for private developers are described, as are the issues of customer contracts and service prices, and customer retrofit financing. The treatment is limited to an introductory overview.

  19. Evaluation of approaches for modeling temperature wave propagation in district heating pipelines

    DEFF Research Database (Denmark)

    Gabrielaitiene, I.; Bøhm, Benny; Sunden, B.

    2008-01-01

    The limitations of a pseudo-transient approach for modeling temperature wave propagation in district heating pipes were investigated by comparing numerical predictions with experimental data. The performance of two approaches, namely a pseudo-transient approach implemented in the finite element...... code ANSYS and a node method, was examined for a low turbulent Reynolds number regime and small velocity fluctuations. Both approaches are found to have limitations in predicting the temperature response time and predicting the peak values of the temperature wave, which is further hampered by the fact...... to be given to the detailed modeling of the turbulent flow characteristics....

  20. Flexible solutions as a strategy for achieving more connections to the district heating network; Flexibla loesningar som strategi foer oekad anslutningsgrad

    Energy Technology Data Exchange (ETDEWEB)

    Henning, Annette; Lorenz, Klaus [Dalarna Univ., Borlaenge (Sweden). Solar Energy Research Center, SERC

    2005-07-01

    According to the project results, two motives are the without comparison most common reasons for owners of single-family houses to reject an offer of district heating installation. One of these motives is a wish to keep a sense of free will and control over their heating system. The second common reason is that a well functioning heat pump or furnace, for example, has already been installed. Installation costs for each single-family house are heavily dependent on the amount of district heating installations that can be made in a certain residential area at a specific time. Therefore, it should be of great interest for energy companies with plans to extend their district heating grid to consider how they could convince households with any of these two main motives to change their mind. District heating companies could ask themselves how they might offer households a way to connect to the district heating grid without loosing their sense of independence, control, and free will. They could also ask themselves how their long-term planning might help them compete with heat pumps and furnaces for bio-fuel and electricity as a replacement for old oil-burning furnaces. These heating systems have the important advantage over district heating that they may be installed whenever it suits each respective household. They also have the advantage of being perceived as easier than district heating to replace at a later stage, thus retaining a sense of free will for household members. Thus, district heating combined with control and free will for the customer is a key issue here, as is the opportunity to have district heating installed at a point in time when it suits each respective household. These key issues are linked to the varying life-cycles of households, houses, and heating systems. Therefore, if district heating companies wish to increase the amount of installations at a specific time, it is of crucial importance for them to focus, not merely on household categories, but

  1. Influence of biomass cofiring on the optimal coefficient of the cogeneration share in a district heating system

    Directory of Open Access Journals (Sweden)

    Ziębik Andrzej

    2014-03-01

    Full Text Available The paper presents a modified algorithm for choosing the optimal coefficient of the share of cogeneration in district heating systems taking into account additional benefits concerning the promotion of highefficiency cogeneration and biomass cofiring. The optimal coefficient of the share of cogeneration depends first of all on the share of the heat required for preparing the hot tap water. The final result of investigations is an empirical equation describing the influence of the ratio of the heat flux for the production of hot tap water to the maximum flux for space heating and ventilation, as well as the share of chemical energy of biomass in the fuel mixture on the optimal value of the share of cogeneration in district heating systems. The approach presented in the paper may be applied both in back-pressure combined heat and power (CHP plants and in extraction-condensing CHP plants.

  2. Evaluation of the support schemes of The District Heating Program during the period 2008 to 2011; Evaluering av stoetteprogrammene for fjernvarme i perioden 2008 til 2011

    Energy Technology Data Exchange (ETDEWEB)

    Lindland, Odd Ivar; Johansen, Staale; Holstad, Jon; Vennes, Wenche; Kallset, Eirik

    2012-11-01

    The District Heating Program as they are designed today, are evaluated after four years of operation, to see if the program works as intended and meet the goals that were set up at the start of 2008. It is also seen in the evaluation of the development of district heating market in the period, to see if there are trends and changes in the regulatory framework that makes it appropriate to make changes to the programs. Users 'perception of the program and the programs' direct and indirect influence on the development of district heating market is also considered. The PricewaterhouseCoopers AS (PwC) has carried out the evaluation, commissioned by Enova. PwC has conducted Internet-based surveys and interviewed actors in various roles within the district. PwC concluded that the goals that were set at the input of the program period is reached. Energy results were higher than expected, while there is a trend that Enova have to pay more and more for the projects. The number of applications and projects has remained fairly stable, while projects have been smaller in size and extent. (eb)

  3. District heating system cools new hotel; Fernwaerme aus KVA kuehlt neues Ibis-Hotel

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, W.

    2009-07-01

    This article takes a look at how an absorption cooling system provides cooling for a new hotel in Basel, Switzerland. The driving energy for the absorption cooling system is provided by the local district heating system. Cheap, summertime heat is provided by the local utility IWB from the city's waste incineration plant to drive the system. Details are presented on the installation and figures are given on cooling power and energy prices. The energy-relevant construction details of the new hotel are examined and the air-conditioning installations are described. The special planning competence involved is commented on. The control of the absorption refrigeration system is looked at in detail and the particular finesse involved in its operation is commented on. The quiet, roof-mounted cooling units are also described and a schematic diagram of the installation is presented.

  4. Regulatory Barriers for Flexible Coupling of the Nordic Power and District Heating Markets

    DEFF Research Database (Denmark)

    Skytte, Klaus; Olsen, Ole Jess

    2016-01-01

    Large share of variable renewable energy sources (VRE) is being deployed in the Nordic countries, especially wind power. This calls for additional flexibility of the power market. With the right coupling to the underlying national and local district heating (DH) markets, large shares of flexibility...... can be generated. However, regulatory barriers and different energy taxes may hinder the potential benefits from systems integration and lower the realisable potentials. By a case study for Denmark we survey and discuss regulatory barriers and drivers for flexibility obtained from DH. We reveal...... that the choice of technologies for heat generation is mainly driven by outdated policies and tax conditions that create barriers for additional flexibility in the overall energy system. However, the balancing markets may be a main driver for introducing more electric boilers into DH and thereby increase its...

  5. Combined use of solar heat and cogeneration - a perspective for district heating?; Kombinierter Einsatz von solarer Waerme und Kraft-Waerme-Kopplung - eine Perspektive fuer die Nahwaerme?

    Energy Technology Data Exchange (ETDEWEB)

    Entress, J. [Deutsches Zentrum fuer Luft- und Raumfahrt (DLR), Stuttgart (Germany). Abt. Systemanalyse und Technikbewertung; Steinborn, F. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany). Fachgebiet Systemanalyse

    1998-02-01

    With Cogeneration of Heat and Power (CHP), climate-endangering CO{sub 2}-emissions can be reduced singificantly. The heat produced can be delivered at prices comparable to those of conventionally produced heat. With solar district heating, yet higher CO{sub 2}-savings are possible but at higher cost. Promising is a combination of CHP and solar district heating: The heat storage of the solar system can be used to level out heat demand, leading to smooth CHP operation, while heat generated by CHP can be used to substitute for low irradiation during the winter period. However, calculations together with simulation and optimization indicate that combining CHP and solar district heating is not the optimal solution in all cases. (orig.) [Deutsch] Der Einsatz von Blockheizkraftwerken (BHKW) kann zu einer deutlichen Reduzierung der klimagefaehrdenden CO{sub 2}-Emissionen beitragen. Dabei kann die ausgekoppelte Waerme etwa zum gleichen Preis wie konventionell erzeugte Waerme abgegeben werden. Hoehere CO{sub 2}-Einsparungen lassen sich hingegen mit solarer Nahwaerme erzielen, allerdings zu hoeheren Kosten. Eine Kombination dieser beiden Waermetechniken verspricht Vorteile: Einerseits kann der Waermespeicher des Solarsystems auch zum Ausgleich von Lastspitzen beim Betrieb des BHKW`s genutzt werden. Andererseits kann die waehrend der einstrahlungsarmen Wintermonate fehlende solare Waerme durch das BHKW erzeugt werden. Detaillierte Simulations- und Optimierungsrechnungen zeigen jedoch, dass eine Kombination dieser Waermetechniken nicht immer empfehlenswert ist. (orig.)

  6. Down-Hole Heat Exchangers: Modelling of a Low-Enthalpy Geothermal System for District Heating

    OpenAIRE

    Carlini, M.; Castellucci, S.; Allegrini, E.; Tucci, A.

    2012-01-01

    In order to face the growing energy demands, renewable energy sources can provide an alternative to fossil fuels. Thus, low-enthalpy geothermal plants may play a fundamental role in those areas—such as the Province of Viterbo—where shallow groundwater basins occur and conventional geothermal plants cannot be developed. This may lead to being fuelled by locally available sources. The aim of the present paper is to exploit the heat coming from a low-enthalpy geothermal system. The experimental ...

  7. Supply of domestic hot Water at comfortable temperatures by low-temperature district heating without risk of Legionella

    DEFF Research Database (Denmark)

    Yang, Xiaochen

    the potential of saving 13% heat loss compared to the decentralized substation system with bypass. The other form is to redirect the bypass flow to the bathroom heating during the non-heating season. With well insulated supply pipe, the bathroom heating flow can substitute for the bypass function......In Denmark, about 25% of the primary energy is consumed for covering the heat demand in the buildings. To achieve a complete renewable energy system by 2050, which is the goal set by the Danish government, methods that are more efficient and economical for heat supply are urgently needed....... Considering the overall energy efficiency and environment effect, the district heating (DH) is a cost-effective way of supplying heat to high heat density area. Currently, the DH system in most countries are still with supply and return temperature at 80/40 °C. The efficiency of the DH system can be improved...

  8. DReAM: Demand Response Architecture for Multi-level District Heating and Cooling Networks

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Saptarshi; Chandan, Vikas; Arya, Vijay; Kar, Koushik

    2017-05-19

    In this paper, we exploit the inherent hierarchy of heat exchangers in District Heating and Cooling (DHC) networks and propose DReAM, a novel Demand Response (DR) architecture for Multi-level DHC networks. DReAM serves to economize system operation while still respecting comfort requirements of individual consumers. Contrary to many present day DR schemes that work on a consumer level granularity, DReAM works at a level of hierarchy above buildings, i.e. substations that supply heat to a group of buildings. This improves the overall DR scalability and reduce the computational complexity. In the first step of the proposed approach, mathematical models of individual substations and their downstream networks are abstracted into appropriately constructed low-complexity structural forms. In the second step, this abstracted information is employed by the utility to perform DR optimization that determines the optimal heat inflow to individual substations rather than buildings, in order to achieve the targeted objectives across the network. We validate the proposed DReAM framework through experimental results under different scenarios on a test network.

  9. The 'Gruessen' district heating scheme in Pratteln, Switzerland; Waermeverbund Gruessen Pratteln. HT-Abwaerme aus ARA Rhein

    Energy Technology Data Exchange (ETDEWEB)

    Lessing, R.

    2006-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) describes a high-temperature district heating scheme in Pratteln, Switzerland that uses waste heat from a regional wastewater treatment plant to provide the basis for a district heating system that provides heating energy for commercial facilities. These include a food distribution centre, various industrial facilities, a school and a hotel. Additional heating power is provided, when necessary, by conventional boilers at the wastewater treatment plant and two of the industrial partners. The report describes the original project and the installations actually built. Total-energy balance, transport losses as well as electrical power requirements are discussed, as is the further development of the scheme, which foresees the integration of a waste-fermentation / biogas facility and a motorway restaurant in the vicinity.

  10. 供暖系统分时分区运行节能分析%Energy saving analysis of time-sharing district operation of heating system

    Institute of Scientific and Technical Information of China (English)

    关银俊; 邵宗义; 宋孝春; 张迪

    2016-01-01

    Based on the traditional heating method,puts forward the time-sharing district heating mode according to the load characteristics of different buildings.Taking an office building located in Beijing as an example,tests the energy consumption after adopting the time-sharing district heating control,and compares the test results with those not adopting the time-sharing district heating mode.The results show that energy consumption can reduce by up to 20%.%在传统供暖方式的基础上,根据不同建筑功能的负荷特点,提出了分时分区供暖方式,即按需供热。针对北京市某办公楼,对采用分时分区控制后的能耗情况进行测试,并与采用分时分区控制前的能耗情况进行对比。通过改变不同工况,分析了逐时耗热量和室内温度的变化情况。测试结果表明,该建筑物的供暖系统在应用分时分区控制后,节能率可达20%。

  11. A Tale of Two Districts: A Comparative Study of Student-Based Funding and School-Based Decision Making in San Francisco and Oakland Unified School Districts

    Science.gov (United States)

    Chambers, Jay; Shambaugh, Larisa; Levin, Jesse; Muraki, Mari; Poland, Lindsay

    2008-01-01

    Though the number of districts with student-based funding-type (SBF) policies has grown, the literature on the implementation and possible impacts of these policies is limited. To address this, this report describes the implementation of SBF policies in two California school districts--San Francisco Unified School District and Oakland Unified…

  12. Development and validation of a detailed TRNSYS-Matlab model for large solar collector fields for district heating applications

    DEFF Research Database (Denmark)

    Bava, Federico; Furbo, Simon

    2017-01-01

    This study describes the development of a detailed TRNSYS-Matlab model to simulate the behavior of a large solar collector field for district heating application. The model includes and investigates aspects which are not always considered by simpler models, such as flow distribution in the differ......This study describes the development of a detailed TRNSYS-Matlab model to simulate the behavior of a large solar collector field for district heating application. The model includes and investigates aspects which are not always considered by simpler models, such as flow distribution...

  13. Evaluations of different domestic hot water preparing methods with ultra-low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    of Legionella in the DHW (domestic hot water) and assure the comfortable temperature, all substations were installed with supplementary heating devices. Detailed measurements were taken in the substations, including the electricity demand of the supplementary heating devices. To compare the energy and economic...... performance of the substations, separate models were built based on standard assumptions. The relative heat and electricity delivered for preparing DHW were calculated. The results showed that substations with storage tanks and heat pumps have high relative electricity demand, which leads to higher integrated...... costs considering both heat and electricity for DHW preparation. The substations with in-line electric heaters have low relative electricity usage because very little heat is lost due to the instantaneous DHW preparation. Accordingly, the substations with in-line electric heaters would have the lowest...

  14. Gray-Box Approach for Thermal Modelling of Buildings for Applications in District Heating and Cooling Networks

    Energy Technology Data Exchange (ETDEWEB)

    Saurav, Kumar; Chandan, Vikas

    2017-05-19

    District-heating-and-cooling (DHC) systems are a proven energy solution that has been deployed for many years in a growing number of urban areas worldwide. They comprise a variety of technologies that seek to develop synergies between the production and supply of heat, cooling, domestic hot water and electricity. Although the benefits of DHC systems are significant and have been widely acclaimed, yet the full potential of modern DHC systems remains largely untapped. There are several opportunities for development of energy efficient DHC systems, which will enable the effective exploitation of alternative renewable resources, waste heat recovery, etc., in order to increase the overall efficiency and facilitate the transition towards the next generation of DHC systems. This motivated the need for modelling these complex systems. Large-scale modelling of DHC-networks is challenging, as it has several components such as buildings, pipes, valves, heating source, etc., interacting with each other. In this paper, we focus on building modelling. In particular, we present a gray-box methodology for thermal modelling of buildings. Gray-box modelling is a hybrid of data driven and physics based models where, coefficients of the equations from physics based models are learned using data. This approach allows us to capture the dynamics of the buildings more effectively as compared to pure data driven approach. Additionally, this approach results in a simpler models as compared to pure physics based models. We first develop the individual components of the building such as temperature evolution, flow controller, etc. These individual models are then integrated in to the complete gray-box model for the building. The model is validated using data collected from one of the buildings at Lule{\\aa}, a city on the coast of northern Sweden.

  15. Comprehensive Assessment of the Potential for Efficient District Heating and Cooling and for High-Efficient Cogeneration in Austria

    Directory of Open Access Journals (Sweden)

    Richard Büchele

    2016-12-01

    Full Text Available In accordance with the EU Energy Efficiency Directive all Member States have to develop a comprehensive assessment of the potential for high-efficient CHP and efficient district heating and cooling by the end of 2015. This paper describes the approach and methodology used to determine the district heating potentials for Austria. In a first step actual and future heating and cooling demand in the building sector is evaluated using the techno-economic bottom-up model Invert/EE-Lab. Relevant infrastructure probably existing in 2025 is investigated and included into the analysis. Technical potentials for efficient technologies are calculated. After a classification of relevant regions into main and secondary regions a country-level cost-benefit-analysis is performed. The results indicate that there is a reasonable additional potential for district heating by the year 2025 under our central scenario assumptions and within sensitivity scenarios. Only in scenarios with high CO2-price or low gas price, CHP is an economically efficient solution to supply district heat.

  16. HEAT PUMP STATION WITH CARBON DIOXIDE AS A WORKING FLUID ENERGY EFFICIENCY GROWTH IN COMBINED DISTRICT HEATING SYSTEM DUE TO ITS CONTROL SYSTEM OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    Sit B.M.

    2008-04-01

    Full Text Available A diagram of the heat pump station (HPS for the central heat supply station of the district heating system, which gets the power from the CHP plant is examined. A block diagram of the control of the system and compressor pressure control system are examined. The description of the control laws of evaporator at the variable heat load of the HPS and control laws of the gas cooler taking into account the goal of achieving the maximum of COP of HPS is shown as well.

  17. Restrained optimism in the district heating sector. AGFW-inquiry on cogeneration, economic trends, district heating; Verhaltener Optimismus in der Fernwaerme-Branche. AGFW-Umfrage zu KWK, Konjunktur, Fernwaerme

    Energy Technology Data Exchange (ETDEWEB)

    Miller, John A. [AGFW Der Energieeffizienzverband fuer Waerme, Kaelte und KWK e.V., Frankfurt am Main (Germany). Bereich Energiepolitik und Waermewirtschaft

    2009-06-15

    There are some trends and counter-trends in the district heating and combined heat and power generation industry today. For example, there are the possible negative effects of the current financial and economic crisis and future emission trading together with the more positive influence of the amendment to the KWKModG (German legislation specifying modernisation of cogeneration plants). For a more accurate estimate of the effects on managers' decisions, AGFW carried out an enquiry among its member businesses. (orig.)

  18. Field investigation on consumer behavior and hydraulic performance of a district heating system in Tianjin, China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Baoping; Fu, Lin; Di, Hongfa [Department of Building Science, Tsinghua University, Beijing 100084 (China)

    2009-02-15

    With the implementation of heat reforms in China, the application of thermostatic radiator valves (TRVs) has been gaining popularity in the new-style district heating systems (DHSs). The objective of this study was to investigate consumer behavior (including regulation of TRVs and opening of windows) and its influences on the hydraulic performance and energy consumption of individuals and the whole system. The concurrence rate of individual behaviors and hydraulic interactions between individuals were analyzed. This study should be helpful to gain a comprehensive understanding of the new DHSs in China and consider a proper design/control strategy for these systems. Questionnaires and field observations of consumer behavior, tests of hydraulic performance, and surveys of energy consumption were carried out in a DHS in Tianjin, which was one of the heat metering and billing demonstration projects in China. The main results of the tests were as follows: water flow performance in apartment-level heating systems were diverse because consumers' behavior was varied and unpredictable, and the hydraulic interaction between consumers living along the line of a vertical pipe was obvious, and was stronger for terminal consumers with their TRVs set to higher values; however, flow variations in the whole DHS, which included 910 households, were relatively constant. A probability analysis was carried out to explain this phenomenon, and the conclusion was drawn that when there were more than 200 consumers, the stochastic consumer regulation behavior would bring less than 10% of total flow variations. Finally, the power consumption of the circulation pump, heat consumption and energy-saving potential of this type of DHS were discussed and some suggestions for TRV regulation and pump operation were made. (author)

  19. Environmental analysis of a potential district heating network powered by a large-scale cogeneration plant.

    Science.gov (United States)

    Ravina, Marco; Panepinto, Deborah; Zanetti, Maria Chiara; Genon, Giuseppe

    2017-05-01

    Among the solutions for the achievement of environmental sustainability in the energy sector, district heating (DH) with combined heat and power (CHP) systems is increasingly being used. The Italian city of Turin is in a leading position in this field, having one of the largest DH networks in Europe. The aim of this work is the analysis of a further development of the network, addressed to reduce the presence of pollutants in a city that has long been subject to high concentration levels. The environmental compatibility of this intervention, especially in terms of nitrogen oxides (NOx) and particulate matter (PM) emissions, is evaluated. The pollutants dispersion is estimated using the CALPUFF model. The forecasting scenario is created firstly by simulating the energy production of the main generation plants in response to the estimated heat demand, and secondly by investigating the amount and the dispersion of pollutants removed due to the elimination of the centralized residential heaters. The results show a future reduction in ground level average NOx concentration ranging between 0.2 and 4 μg/m(3). The concentration of PM remains almost unchanged. Measures are then taken to lower the uncertainty in the simulation scenarios. This study provides important information on the effects of a change of the energy configuration on air quality in an urban area. The proposed methodological approach is comprehensive and repeatable.

  20. Regulation models for district heating. Main report; Denmark; Reguleringsmodeller for fjernvarmen. Hovedrapport

    Energy Technology Data Exchange (ETDEWEB)

    2012-02-15

    With regard to choice of model for the regulation of district heating prices the report points out that a detailed analysis of a cost+ model could be considered. Such an analysis could provide further definition of the extended right to recoup the investment for heating companies, the shaping of the possibility of recognition of opportunity costs and the fixed cost allocation, and the clarified definition of necessary costs. The report also suggests that a price cap regulation or a completely free pricing in the entire sector is hardly appropriate forms of regulation. The report's analysis clearly shows that the choice of price regulation in the heat sector has impact on the incentives in terms of investment, green conversion, etc. It also appears that the different regulatory models have very different advantages and disadvantages, and lessons learned from other sectors and abroad show that changing price regulation rules can be a difficult and lengthy process with unintended consequences along the way. (LN)

  1. Corrosion Behavior of Pipeline Carbon Steel under Different Iron Oxide Deposits in the District Heating System

    Directory of Open Access Journals (Sweden)

    Yong-Sang Kim

    2017-05-01

    Full Text Available The corrosion behavior of pipeline steel covered by iron oxides (α-FeOOH; Fe3O4 and Fe2O3 was investigated in simulated district heating water. In potentiodynamic polarization tests; the corrosion rate of pipeline steel is increased under the iron oxide but the increaseing rate is different due to the differnet chemical reactions of the covered iron oxides. Pitting corrosion was only observed on the α-FeOOH-covered specimen; which is caused by the crevice corrosion under the α-FeOOH. From Mott-Schottky and X-ray diffraction results; the surface reaction and oxide layer were dependent on the kind of iron oxides. The iron oxides deposit increases the failure risk of the pipeline and localized corrosion can be occurred under the α-FeOOH-covered region of the pipeline. Thus, prevention methods for the iron oxide deposit in the district pipeline system such as filtering or periodic chemical cleaning are needed.

  2. The Feasibility of Communication Among Pumps in a District Heating System

    DEFF Research Database (Denmark)

    Meybodi, Soroush Afkhami; Dohler, Mischa; Askarpour, Amir Nader

    2013-01-01

    and experimental results for some others, followed by selection of the most appropriate option. The methods considered used (1) acoustic waves through water and pipelines; (2) power-line communications; (3) the electrical conductivity of pipes; (4) cell-phone infrastructure; (5) free and guided radio-frequency (RF...... control systems for similar urban utilities motivates this research problem. Here we have reported the results of investigating several potential methods for realizing the idea of “the talking pumps” in a district heating system. This includes a diverse list of key references, simulations for some methods......) electromagnetic (EM) waves; and (5) free and guided very low frequency (VLF) electric and magnetic fields, also known as magnetic induction. The viability of the latter method was verified by simulations and primitive experimental results....

  3. Numerical investigation on the axial interaction between buried district heating pipes and soil

    Energy Technology Data Exchange (ETDEWEB)

    Weidlich, Ingo; Achmus, Martin

    2008-09-15

    Pipe-soil interaction has to be taken into account in the design of district heating (DH) pipes. The investigation presented here focuses on the effect of the reduction of axial friction forces due to cyclic axial displacements and the corresponding stress redistribution. Calculations with a three-dimensional finite element model were carried out in which a standard situation of a buried DH pipe was studied. A significant reduction of friction with cyclic axial displacements was obtained, although no temperature loading and thus no radial expansion of the pipe was considered. The reason for the friction force decrease is a densification of the soil beneath the pipe, which leads to a decrease of the normal stress acting between pipe and soil.

  4. District space heating potential of low temperature hydrothermal geothermal resources in the southwestern United States. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    McDevitt, P.K.; Rao, C.R.

    1978-10-01

    A computer simulation model (GIRORA-Nonelectric) is developed to study the economics of district space heating using geothermal energy. GIRORA-Nonelectric is a discounted cashflow investment model which evaluates the financial return on investment for space heating. This model consists of two major submodels: the exploration for and development of a geothermal anomaly by a geothermal producer, and the purchase of geothermal fluid by a district heating unit. The primary output of the model is a calculated rate of return on investment earned by the geothermal producer. The results of the sensitivity analysis of the model subject to changes in physical and economic parameters are given in this report. Using the results of the economic analysis and technological screening criteria, all the low temperature geothermal sites in Southwestern United States are examined for economic viability for space heating application. The methodology adopted and the results are given.

  5. Book of abstracts: 3rd International Conference on Smart Energy Systems and 4th Generation District Heating

    DEFF Research Database (Denmark)

    Lund, Henrik; Mathiesen, Brian Vad

    of the European 2020 goals as well as future sustainable energy solutions in general. The Smart Energy System approach was defined in 2011 in the CEESA project. The project addressed Danish scenarios with a particular focus on renewable energy in the transport system in a context with limited access to bioenergy....... The Smart Energy System concept is essential for 100% renewable energy systems to harvest storage synergies and exploit low-value heat sources. The most effective and least-cost solutions are to be found when the electricity sector is combined with the heating and cooling sectors and/or the transport sector....... Moreover, the combination of electricity and gas infrastructures may play an important role in the design of future renewable energy systems. In its research on low-temperature district heating, the Strategic Research Centre for 4th Generation District Heating Technologies and Systems enhances...

  6. Modelling the Heat Consumption in District Heating Systems using a Grey-box approach

    DEFF Research Database (Denmark)

    Nielsen, Henrik Aalborg; Madsen, Henrik

    2006-01-01

    identification of an overall model structure followed by data-based modelling, whereby the details of the model are identified. This approach is sometimes called grey-box modelling, but the specific approach used here does not require states to be specified. Overall, the paper demonstrates the power of the grey......-box approach. (c) 2005 Elsevier B.V. All rights reserved....

  7. Modelling the Heat Consumption in District Heating Systems using a Grey-box approach

    DEFF Research Database (Denmark)

    Nielsen, Henrik Aalborg; Madsen, Henrik

    2006-01-01

    identification of an overall model structure followed by data-based modelling, whereby the details of the model are identified. This approach is sometimes called grey-box modelling, but the specific approach used here does not require states to be specified. Overall, the paper demonstrates the power of the grey......-box approach. (c) 2005 Elsevier B.V. All rights reserved....

  8. A Comparative Study on Substation Types and Network Layouts in Connection with Low-Energy District Heating Systems

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2012-01-01

    The study deals with low-energy district heating (DH) networks operating in low temperatures such as 55 °C in terms of supply and 25 °C in terms of return. The network layout, additional booster pumps, and different substation types such as storage tanks either equipped or not equipped in domestic...

  9. Thermo-economic optimization of secondary distribution network of low temperature district heating network under local conditions of South Korea

    DEFF Research Database (Denmark)

    Park, Byung Sik; Imran, Muhammad; Hoon, Im-Yong

    2017-01-01

    A secondary distribution network of a low temperature district heating system is designed and optimized for a residential apartment complex under the local conditions of South Korea in the TRNSYS simulation environment. The residential apartment complex is a typical example of Korean residential...

  10. Master plan study - District heating Kohtla-Jaerve and Johvi municipalities. Estonia. Final report. Appendices for chapter 9

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The appendices to chapter nine of the final report of the master plan study on district heating in the municipalities of Kohtla-Jarve and Johvi municipalities (Estonia) present extensive data relating to economic, financial and environmental calculations, fuel consumption, energy balance and prices. (ARW)

  11. Case study on natural gas application for district heating and cooling in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Maues, Jair Arone [Pontificia Universidade Catolica do Rio de Janeiro (IE/PUC-Rio), Rio de Janeiro, RJ (Brazil). Inst. de Energia; Akiyama, Junichi [Mitsui Gas e Energia do Brasil Ltda., Rio de janeiro, RJ (Brazil)

    2012-07-01

    The distributed cogeneration applying natural gas consists in an excellent alternative to use this source, but it is limited by a compatible heat demand that must be found in its application. District heating and cooling solutions can overcome this hurdle, especially in Brazil, a tropical country, where new industrial and commercial enterprises usually install central air conditioning systems. By 2020 natural gas demand shall reach a value of more than 200 MM m{sup 3} per day, accordingly to the Brazilian Energy Research Office (EPE, 2011). An expressive part of it could be consumed in cogeneration systems like the one described in this paper. This project had a special taxes exception rule applied. The chilled water and heated thermal oil produced were not taxed at all. But these two DHC utilities could obtain a different treatment if someone considers this is a tricky way of power and heat trading, which should be taxed as electricity and natural gas normally are. A bolder legislation with respect to the export of energy surplus would facilitate the project and operation of this kind of system, because the basic premise would be to attend the thermal demand with the electrical power installed, maximizing the global efficiency of the installation. An average 8 GW of Brazilian power demand, with roughly 50 MMm{sup 3}/day of natural gas consumption, could be attended by distributed energy gas cogeneration enterprises. If this prediction were totally accomplished it would bring the Brazilian participation of distributed energy in total power generation to values close to 10% in 2020, value already reached in average by the world biggest electricity's consumer countries (WADE, 2006). This also would mean an equivalent investment economy of approximately 11,000 MW in transmission and distribution lines capacity (author)

  12. Impact of different national biomass policies on investment costs of biomass district heating plants. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-04-01

    The BIO-COST project - co-ordinated by E.V.A. - was funded by the European Commission's THERMIE Type B Programme. The objective of BIO-COST was to analyse the impact of national biomass policies on the investment costs of biomass district heating (DH) plants. The European comparison should help identifying measures to reduce investment costs for biomass DH plants and/or components down to a 'best practice' level. The investigation is based on the comparison of 20 biomass DH plants by country, with Denmark and Sweden having mainly high energy taxes as driver, while Austria and France rely mainly on subsidy systems. The results of BIO-COST show, that governmental policies can have a big impact especially on grid and buildings costs, effecting of course the overall costs of the plant enormously. Emission standards have their effects especially on the costs for technical equipment, however, this fact was not reflected in the BIO-COST data. The results do not show a clear advantage of either the energy tax approach or the subsidy approach: The French subsidy approach leads to fairly low cost levels compared to the Danish tax approach, while the Swedish tax approach seems to yield the lowest cost level. On the other hand the Austrian subsidy approach seems to intercrease investment costs. In principle both the tax as the subsidy approach can lead to the same effect: a project is calculated in such a way, that it just meets economic breakeven. This is typically the case when the project is not carried out by a private enterprise but by an operator aiming at enhanced public welfare (e.g. co-operative, municipality). In this case a subsidy model might yield more possibilities to encourage an economically efficient development, than a tax. Instead of giving subsidies as a fixed percentage of investments they could be adjusted to the actual needs of the project as proven by a standardised calculation. Of course this can create the incentive to expect higher

  13. Energy, economy and exergy evaluations of the solutions for supplying domestic hot water from low-temperature district heating in Denmark

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    . Evaluation models were built to investigate the energy, economy and exergy performances of the proposed domestic hot water systems in various configurations. The configurations of the devised domestic hot water substations were optimised to fit well with both low and ultra-low-temperature district heating...... and to reduce the return temperature to district heating. The benefits of lower return temperatures were also analysed compared with the current district heating situation. The evaluation results show that the decentralized substation system with instantaneous heat exchanger unit performed better under the 65...

  14. Safeguarding the future of district heating. Development prospects in the Rural district; Zukunftssicherung Fernwaerme. Entwicklungsperspektiven im Ruhrgebiet. Reduzierung der CO{sub 2}-Emissionen

    Energy Technology Data Exchange (ETDEWEB)

    Donner, Oliver; Schrader, Knut [BET Buero fuer Energiewirtschaft und Technische Planung GmbH, Aachen (Germany)

    2013-07-15

    The national climate change objectives provide a strong reduction of the emissions of carbon dioxide. The aim is to reduce the emissions by 40 % up to the year 2020, or at least 85% up to the year 2050 compared to the year 1990. Also, the country-specific targets of North Rhine-Westphalia provide a strong reduction of the emissions of carbon dioxide by 25% up to 2020 and 80% up to 2050 also compared to 1990. The authors of this paper examine the contribution of the Ruhr district in order to achieve the emission targets of North Rhine-Westphalia. For this, two scenarios of the energy markets, the heat demand, scenarios with and without the power plant Datteln 4 and different versions of the network in the Ruhr district are situated.

  15. Simple, clear and informative price models for district heating to detached houses; Enkla, tydliga och informativa prismodeller foer fjaerrvaerme till smaahus

    Energy Technology Data Exchange (ETDEWEB)

    Wiren, Christer [Consevo AB, Vaesterlanda (Sweden)

    2005-07-01

    This report deals with pricing and price models of district heating for single-family houses. The purpose of this study is to give proposals for price models which meet with customer demands for freedom of choice regarding charges for connection and heating consumption of single-family houses. Equally these price models should consider the needs of district heating companies for sound economy of this business in the long term. The scope of the project has covered both the customer and the company side of the market for district heating to single-family houses. Customers consider distant heating to be advantageous both with regard to costs and to comfort. Therefore it is important for companies to facilitate for customers to finance the installation of district heating and to offer alternatives of different heating consumption fees. A distinctive feature of district heating is that the companies have control of the total value chain from the installation of the boiler to the actual supply of the heating with options also to offer various service support. This means that district heating companies have the possibility to price either the district heating boiler and the district heating separately or in various forms of combinations. This is a distinct advantage that the report recommends companies to exploit to the maximum in order to benefit from the market potential. The report recommends five different price models, which should give the companies sound finances and the customers an optimal freedom of choice regarding the balance between the connection fees and the heating consumption fees.

  16. Monitoring and characterisation of bacteria in corroding district heating systems using fluorescence in situ hybridisation and microautoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Kjellerup, B.V. [Danish Technological Institute, Teknologiparken (Denmark). Dept. of Environment; Aalborg University (Denmark). Dept. of Environmental Engineering; Olesen, B.H.; Frolund, B. [Danish Technological Institute, Teknologiparken (Denmark). Dept. of Environment; Nielsen, J.L.; Nielsen, P.H. [Aalborg University (Denmark). Dept. of Environmental Engineering; Odum, S. [CTR I/S, Frederiksberg (Denmark)

    2003-07-01

    Presence of biofilm and biocorrosion has been observed in Danish district heating (DH) systems despite very good water quality that was expected to prevent significant microbial growth. The microbiological water quality was investigated in order to identify the dominating bacterial groups on surfaces with corrosion problems. Water samples from 29 DH systems were investigated for the total number of bacteria and presence of sulphate reducing bacteria (SRBs). SRBs were found to be present in more than 80% of the DH systems. The microbial population in samples from 2 DH systems (biofilm from a test coupon and an in situ sample from a heat exchanger) was investigated with fluorescence in situ hybridisation, and the results showed significant differences in population composition. Betaproteobacteria was the dominant population in both samples. SRBs were present in both samples but were most numerous in the biofilm from the test coupon. Examination of functional groups based on uptake of radiolabelled acetate (microautoradiography) showed presence of both aerobic and anaerobic bacteria despite the fact that oxygen is not anticipated in DH systems. (author)

  17. Economic connection consolidation by means of a small district heating house connection; Wirtschaftliche Anschlussverdichtung durch einen kleinen Fernwaermehausanschluss

    Energy Technology Data Exchange (ETDEWEB)

    John, Dietmar [enercity Netzgesellschaft mbH, Hannover (Germany); Kraft, Soenke [Fernwaerme-Forschungsinstitut GmbH, Hemmingen (Germany); Weidlich, Ingo [AGFW e.V., Frankfurt am Main (Germany)

    2013-02-01

    There a lot of technical opportunities and competing systems at the market for the last meter to the customer. These technical opportunities and competing systems enable a cost-effective construction under the prevailing general conditions. With decreasing installed power the pressure of cost increases. In the past, the enhanced number of potential customers within the lower power range up to nearly 100 kW could not be connected due to economic reasons. Thus a project with the title 'Development of an economic district heating house connection for low thermal output' was initiated. The findings supply important components for the economic expansion of district heating and are pioneering for the further development in the area of the house-installed load for heat distribution systems.

  18. Development of a unit suitable for corrosion monitoring in district heating systems. Experiences with the LOCOR-cell test method

    DEFF Research Database (Denmark)

    Andersen, Asbjørn; Hilbert, Lisbeth Rischel

    2004-01-01

    the purpose, background and gained results of one of the used monitoring techniques, the crevice corrosion measurements obtained by the LOCOR-Cell„§. The crevice corrosion cell was developed by FORCE Technology in a previous district heating project financed by Nordic Industrial Fund (1)(2). Results from...... in 6 pressurised circulating heating systems and in one cooling system. 7 different corrosion monitoring methods have been used to study corrosion rates and types in dependency of water chemistry. This paper describes the design of the by-pass unit including water analysis methods. It also describes...... other used corrosion monitoring methods in the project are described elsewhere (3) and (4). For future district heating corrosion monitoring the by-pass unit can be recommended for permanent installation and the two methods high sensitive ER-technique (Metricorr) and the LOCOR-Cell„§ (FORCE Technology...

  19. Development of a unit suitable for corrosion monitoring in district heating systems. Experiences with the LOCOR-cell test method

    DEFF Research Database (Denmark)

    Andersen, Asbjørn; Hilbert, Lisbeth Rischel

    2004-01-01

    the purpose, background and gained results of one of the used monitoring techniques, the crevice corrosion measurements obtained by the LOCOR-Cell„§. The crevice corrosion cell was developed by FORCE Technology in a previous district heating project financed by Nordic Industrial Fund (1)(2). Results from...... in 6 pressurised circulating heating systems and in one cooling system. 7 different corrosion monitoring methods have been used to study corrosion rates and types in dependency of water chemistry. This paper describes the design of the by-pass unit including water analysis methods. It also describes...... other used corrosion monitoring methods in the project are described elsewhere (3) and (4). For future district heating corrosion monitoring the by-pass unit can be recommended for permanent installation and the two methods high sensitive ER-technique (Metricorr) and the LOCOR-Cell„§ (FORCE Technology...

  20. District heating and cooling systems for communities through power-plant retrofit and distribution network. Volume 2. Tasks 1-3. Final report. [Downtown Toledo steam system

    Energy Technology Data Exchange (ETDEWEB)

    Watt, J.R.; Sommerfield, G.A.

    1979-08-01

    Each of the tasks is described separately: Task 1 - Demonstration Team; Task 2 - Identify Thermal Energy Source(s) and Potential Service Area(s); and Task 3 - Energy Market Analysis. The purpose of the project is to establish and implement measures in the downtown Toledo steam system for conserving scarce fuel supplies through cogeneration, by retrofit of existing base- or intermediate-loaded electric-generating plants to provide for central heating and cooling systems, with the ultimate purpose of applying the results to other communities. For Task 1, Toledo Edison Company has organized a Demonstration Team (Battelle Columbus Laboratories; Stone and Webster; Ohio Dept. of Energy; Public Utilities Commission of Ohio; Toledo Metropolitan Area Council of Governments; and Toledo Edison) that it hopes has the expertise to evaluate the technical, legal, economic, and marketing issues related to the utilization of by-product heat from power generation to supply district heating and cooling services. Task 2 gives a complete technical description of the candidate plant(s), its thermodynamic cycle, role in load dispatch, ownership, and location. It is concluded that the Toledo steam distribution system can be the starting point for developing a new district-heating system to serve an expanding market. Battelle is a member of the team employed as a subcontractor to complete the energy market analysis. The work is summarized in Task 3. (MCW)

  1. Potentials of district heating grids for climate protection up to the year 2020; Potenziale von Nah- und Fernwaermenetzen fuer den Klimaschutz bis zum Jahr 2020

    Energy Technology Data Exchange (ETDEWEB)

    Fischedick, Manfred; Schuewer, Dietmar; Venjakob, Johannes; Merten, Frank; Mitze, Dirk [Wuppertal Inst. fuer Klima, Umwelt, Energie GmbH (Germany); Nast, Michael; Schillings, Christoph; Krewitt, Wolfram [Deutsches Zentrum fuer Luft- und Raumfahrt (Germany). Inst. fuer Technische Thermodynamik; Bohnenschaefer, Werner; Lindner, Klaus [Institut fuer Energetik und Umwelt, Leipzig (Germany)

    2007-12-15

    District heat is one of Germany's traditional end use energy sources, with a connected capacity of about 57,000 MWth. The heat is distributed via 1,400 grids with a total length of about 19,000 km. The number of households supplied with district heat increased from 9.7 percent in 1993 to 13.7 percent in 2003. About 550 out of about 1,000 German utilities provide district heat to households. During the past few years, the connected capacity of district heating has been stagnating. This is the result of thermal insulation measures, dismantling and abandonment of supply grids, but also of changes on the demand side that can still be compensated by concentration and expansion potentials.

  2. Annual measured and simulated thermal performance analysis of a hybrid solar district heating plant with flat plate collectors and parabolic trough collectors in series

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2017-01-01

    in large solar heating plants for a district heating network, a hybrid solar collector field with 5960 m2 flat plate collectors and 4039 m2 parabolic trough collectors in series was constructed in Taars, Denmark. The design principle is that the flat plate collectors preheat the return water from...... for this type of hybrid solar district heating plants with flat plate collectors and parabolic trough collectors in the Nordic region, but also introduce a novel design concept of solar district heating plants to other high solar radiation areas.......Flat plate collectors have relatively low efficiency at the typical supply temperatures of district heating networks (70–95 °C). Parabolic trough collectors retain their high efficiency at these temperatures. To maximize the advantages of flat plate collectors and parabolic trough collectors...

  3. Iterative Feedback Tuning in district heating systems; Iterative Feedback Tuning i vaermeproduktionsanlaeggningar

    Energy Technology Data Exchange (ETDEWEB)

    Raaberg, Martin; Velut, Stephane; Bari, Siavosh Amanat

    2010-10-15

    The project goal is to evaluate and describe how Iterative Feedback Tuning (IFT) can be used to tune controllers in the typical control loops in heat- and power plants. There are only a few practical studies carried out for IFT and they are not really relevant for power and heat processes. It is the practical problems in implementing the IFT and the result of trimming that is the focus of this project. The project will start with theoretical studies of the IFT-method, then realization and simple simulations in scilab. The IFT equations are then implemented in Freelance 2000, an ABB control system, for practical tests on a SISO- and a MIMO-process. By performing reproducible experiments on the process and analyze the results IFT can adjust the controller parameters to minimize a cost function that represents the control goal. The project selected for SISO experiments a pressure controller in an oil transportation system. By controlling the valve position of a control valve for the reversal to the supply tank, the pressure in the oil transport system is regulated. A disturbance in oil pressure can be achieved by changing the position of a valve that lets oil through to the day tank. The selected MIMO-process is a pre-heater in a degassing process. In this process, a valve on the secondary side is utilized to control the flow in the secondary system. A valve on the primary side is utilized to control the district heating water flow through the heat exchanger to control the temperature on the secondary side. An increased secondary flow increases the heat demand and thus requiring an increase in primary flow to maintain the secondary side outlet temperature. This is the cross-coupling responsible for why it is an advantage to consider the process as multi-variable. Using the IFT method, the two original PID-controllers and a feed-forward controller is tuned simultaneously. IFT-method was difficult to implement but worked well in both simulations and in real processes

  4. Integrated production and distribution analysis in District Heating-systems; Samverkande produktions och distributionsanalys i fjaerrvaermesystem

    Energy Technology Data Exchange (ETDEWEB)

    Rossing, Ola [HydroRam, Goeteborg (Sweden); Johnsson, John [Profu, Goeteborg (Sweden)

    2005-01-01

    During the last 10-15 years detailed models for analysing district heating production and distribution has been developed. However, detailed analysis of district heating is in many cases a combined production and distribution issue. The high complexity in both areas has lead to a situation with separate tools for analysis. The consequence of this is that the calculations have, in some cases, been incomplete or even incorrect. Examples of miscalculations are that production calculations in complex systems in many cases give unrealistic production schedules due to the distribution restrictions. On the other hand most distribution calculations do not give economical results. Through integration of production and distribution analyses the analyst is given possibility to verify the production calculation from a distributions perspective and to reach a more realistic result. In order to evaluate the advantage of, and possibilities for, co-operation between the two areas, we have analysed the district heating system of Goeteborg, which is a district heating system of high complexity. The calculations have been made with a production model (Martes) and a distribution model (PFC-SF). The possibility to establish integrated analysis has been evaluated through analysing different technical measures for minimizing the influence of a distribution restriction between the western and eastern part of Goeteborg. The project shows that integrated analysis could be done with a high degree of accuracy and in an effective way. In the project six different measures for minimizing the influences of the distribution restriction was identified. These measures were ranked on an economic basis through the integrated analyses. The change of cost was varied between a cost decrease of seven million SEK/year (increases differential pressure) to a cost increases of 32 million SEK/year (increased supply temperature). The cost reduction of the other measures varied between four and seven million

  5. Solar-assisted district heating systems: The Solarthermie 2000-programme; Solarunterstuetzte Nahwaermeversorgung: Programm Solarthermie-2000

    Energy Technology Data Exchange (ETDEWEB)

    Lottner, V. [Forschungszentrum Juelich GmbH (Germany). Projekttraeger Biologie, Energie, Umwelt (BEO)

    1998-12-31

    In Germany, utilisation of solar energy for thermal energy supply has a considerable technical and economic potential in terms of substitution of fossil fuels and reduction of CO{sub 2} emission. If appropriate technologies are used, solar-assisted district heat supply systems can be a cost-efficient concept for thermal utilisation of solar energy. The BMBF -programme `Solarthermie 2000` supports a number of pilot and demonstration plants in order to test and develop the most promising systems and storage facilities under real conditions. Long-term measuring programmes generate reliable data on thermal performance and cost of the plant concepts and create a solid basis for a technical and economic evaluation. (orig.) [Deutsch] Die Nutzung von Solarenergie fuer die Waermeversorgung bietet in Deutschland ein grosses technisches und wirtschaftliches Potential zur Substitution fossiler Energietraeger und Reduzierung der CO{sub 2} Emissionen in die Atmosphaere. Solarunterstuetzte Nahwaermesysteme stellen unter guenstigen technischen Bedingungen ein kostenguenstiges Konzept der thermischen Nutzung der Solarenergie dar. In dem BMBF-Programm Solarthermie-2000 werden Pilot- und Demonstrationsanlagen gefoerdert, so dass die aussichtsreichsten System- und Speicherkonzepte in der Praxis erprobt und gezielt weiterentwickelt werden koennen. Mit Langzeit-Messprogrammen werden belastbare Werte der thermischen Leistung und Kosten der Anlagenkonzepte ermittelt und eine zuverlaessige Grundlage fuer die technisch-wirtschaftliche Bewertung geschaffen. (orig.)

  6. Geothermal energy and district heating in Ny-Ålesund, Svalbard

    OpenAIRE

    Iversen, Julianne

    2013-01-01

    This thesis presents the possibilities for using shallow geothermal energy for heating purposes in Ny-Ålesund. The current energy supply in Ny-Ålesund is a diesel generator, which does not comply with the Norwegian government and Ny-Ålesund Science Managers Committee’s common goal to maintain the natural environment in Ny-Ålesund. Ny-Ålesund has a potential for replacing the heat from the current diesel based energy source with geothermal energy. Geothermal energy is considered to have low im...

  7. District heating and cooling systems for communities through power plant retrofit and distribution network, city of Piqua, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-01-01

    The feasibility analysis and evaluation of the Piqua, Ohio District Heating and Cooling Demonstration program is being conducted by the Piqua Municipal Power Co., the Piqua Law Dept., the Public Works Dept., a firm of economic analysts, and the Georgia Tech Engineering Dept. This volume contains information on the organization and composition of the demonstration team; characterization of the Piqua community; and the technical, environmental, institutional; financial, and economic assessments of the project. (LCL)

  8. District heating systems - the necessary infrastructure for geothermal energy; Fern- und Nahwaermesysteme - notwendige Infrastruktur fuer die Geothermie

    Energy Technology Data Exchange (ETDEWEB)

    Schoenberg, I. [Inst. fuer Umwelt-, Sicherheits- und Energietechnik e.V. (UMSICHT), Oberhausen (Germany)

    1997-12-01

    The contribution discusses the future chances of geothermal energy use with cost-optimized systems of geothermal energy + cogeneration + district heating and with the focus on innovation instead of state funding. (orig./AKF) [Deutsch] Der Beitrag bezieht sich auf die zukuenftigen Chancen der Geothermie, die eine kostenoptimierte Systemloesung Geothermie + KWK + Nah-/Fernwaerme sowie durch Mut zur Innovation und nicht durch Foerderung bestimmt werden. (orig./AKF)

  9. The Forest Energy Chain in Tuscany: Economic Feasibility and Environmental Effects of Two Types of Biomass District Heating Plant

    Directory of Open Access Journals (Sweden)

    Claudio Fagarazzi

    2014-09-01

    Full Text Available The purpose of this study was to examine two biomass district heating plants operating in Tuscany, with a specific focus on the ex-post evaluation of their economic and financial feasibility and of their environmental benefits. The former biomass district heating plant supplies only public users (Comunità Montana della Lunigiana, CML: administrative body that coordinates the municipalities located in mountain areas, the latter supplies both public and private users (Municipality of San Romano in Garfagnana. Ex-post investment analysis was performed to check both the consistency of results with the forecasts made in the stage of the project design and on the factors, which may have reduced or jeopardized the estimated economic performance of the investment (ex-ante assessment. The results of the study point out appreciable results only in the case of biomass district heating plants involving private users and fuelled by biomasses sourced from third parties. In this case, the factors that most influence ex-post results include the conditions of the woody biomass local market (market prices, the policies of energy selling prices to private users and the temporal dynamics of private users’ connection. To ensure the consistency of ex-post economic outcome with the expected results it is thus important to: (i have good knowledge of the woody local market; (ii define energy selling prices that should be cheap for private users but consistent with energy production costs and (iii constrain private users beforehand to prevent errors in the plant design and in the preliminary estimate of return on investment. Moreover, the results obtained during the monitoring activities could help in providing information on the effectiveness of the supporting measures adopted and also to orient future choices of policy makers and particularly designers, to identify the most efficient configuration of district heating organization for improving energy and

  10. Detection and location of leaks in district heating steam systems: Survey and review of current technology and practices

    Energy Technology Data Exchange (ETDEWEB)

    Kupperman, D.S.; Raptis, A.C.; Lanham, R.N.

    1992-03-01

    This report presents the results of a survey undertaken to identify and characterize current practices for detecting and locating leaks in district heating systems, particular steam systems. Currently used technology and practices are reviewed. In addition, the survey was used to gather information that may be important for the application of acoustic leak detection. A few examples of attempts to locate leaks in steam and hot water pipes by correlation of acoustic signals generated by the leaks are also discussed.

  11. Site-Based Budgeting: A New Age of District Finance

    Science.gov (United States)

    Perry, Mary

    2013-01-01

    The effects of linking school districts' funding directly to the students they serve and providing local school districts and communities with more control over how that money is spent could ripple through the entire K-12 system, from the state Capitol to the classroom. For district leaders anxious to improve their schools and better support…

  12. District heating and cooling systems for communities through power plant retrofit and distribution network, City of Piqua, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-09-18

    The goal of the Piqua, Ohio District Heating and Cooling Demonstration Project is to demonstrate the feasibility and efficiency of using cogenerated thermal energy from the City's Municipal Power Plant to provide residential, commercial and industrial space heating and cooling and satisfy other community energy needs as appropriate. Progress in four tasks within this project is reported. These tasks include: development of team work plan resource allocation; identification of thermal energy source market; analysis of energy market; and planning of power plant retrofits. (LCL)

  13. District heating and cooling systems for communities through power plant retrofit distribution network. Final report, September 1, 1978-May 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-10-01

    This Final Report (Volume 2) of Phase 1 of District Heating for Communities Through Power Plant Retrofit Distribution Network contains 3 tasks: (1) Demonstration Team; (2) Identify Thermal Energy Sources and Potential Service Areas; and (3) Energy Market Analysis. Task 2 consists of estimating the thermal load within 5 and 10 miles of Public Service Electric and Gas Company steam power plants, Newark, New Jersey; estimating the costs of supplying thermal services to thermal loads of varying densities; a best case economic analysis of district heating for single-family homes; and some general comments on district-heating system design and development. Task 3 established the potential market for district heating that exists within a 5-mile radius of the selected generating stations; a sample of the questionnaire sent to the customers are shown. (MCW)

  14. Waste incineration within the Swedish district heating systems - Sub-Project 4; Avfallsfoerbraenning inom Sveriges fjaerrvaermesystem - Delprojekt 4 inom projektet Perspektiv paa framtida avfallsbehandling

    Energy Technology Data Exchange (ETDEWEB)

    Haraldsson, Maarten; Holmstroem; David

    2012-07-01

    Waste incineration within the Swedish district heating systems is one of the five sub-projects within the project Perspectives on sustainable waste treatment. The goal of this project is to evaluate the economic potential for waste incineration in the Swedish district heating systems. With the current expansion of incineration, we may relatively soon reach an upper limit for what is demanded by the Swedish district heating systems. How much more waste incineration that is economically attractive to build is of great importance for the development of the Swedish waste system, not least for the alternatives to incineration as for example biogas production. With continued rising quantities of waste and stagnant demand for waste incineration from the district heating systems, today's surplus of treatment capacity may change the market picture for other waste treatment options. How much more waste incineration requested and how quickly the market reaches this level is studied in this project.

  15. Extension and improvement of Central Station District heating budget period 1 and 2, Krakow Clean Fossil Fuels and Energy Efficiency Program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    Project aim was to reduce pollution levels in the City of Krakow through the retirement of coal-fired (hand and mechanically-stoked) boiler houses. This was achieved by identifying attractive candidates and connecting them to the Krakow district heating system, thus permitting them to eliminate boiler operations. Because coal is less costly than district hot water, the district heating company Miejskie Przedsiebiorstwo Energetyki Cieplnej S.A., henceforth identified as MPEC, needed to provide potential customers with incentives for purchasing district heat. These incentives consisted of offerings which MPEC made to the prospective client. The offerings presented the economic and environmental benefits to district heating tie-in and also could include conservation studies of the facilities, so that consumption of energy could be reduced and the cost impact on operations mitigated. Because some of the targeted boiler houses were large, the capacity of the district heating network required enhancement at strategic locations. Consequently, project construction work included both enhancement to the district piping network as well as facility tie-ins. The process of securing new customers necessitated the strengthening of MPEC`s competitive position in Krakow`s energy marketplace, which in turn required improvements in marketing, customer service, strategic planning, and project management. Learning how US utilities address these challenges became an integral segment of the project`s scope.

  16. Building ground analyses and expert opinions in district heating pipeline construction. Geotechnical investigations according to DIN 4020; Baugrunduntersuchungen und Baugrundgutachten im Fernwaermeleitungsbau. Geotechnische Untersuchungen nach DIN 4020

    Energy Technology Data Exchange (ETDEWEB)

    Weidlich, Ingo [AGFW Energieeffizienzverband fuer Waerme, Kaelte und KWK e.V., Frankfurt am Main (Germany)

    2010-12-15

    During construction of district heating pipelines, the specifications of the pertinent technical rules must be observed in order to ensure regular construction and to prevent damage. In principle, analyses of the building ground are required depending on the construction project and the pertinent DIN standards. The author lists the standards that are relevant for geotechnical operation, makes an evaluation of these standards, and explains their relevance in the construction of district heating pipelines. (orig.)

  17. Management of power economical risks in the district heating at Vienna. Risk management as chance management; Management energiewirtschaftlicher Risiken bei Fernwaerme Wien. Risikomanagement als Chancenmanagement

    Energy Technology Data Exchange (ETDEWEB)

    Pschick, Andreas [Fernwaerme Wien GmbH, Vienna (Austria). Abt. Energiewirtschaft

    2009-05-15

    District heat supply companies are exposed to different risks. Some examples are the legal guidelines of the European Union, increased combustible prices, more warm winters and the required use of CO{sub 2} certificates. A risk management in the field of energy economy is therefore indispensable. The author explains the risk management in the district heating at Vienna. The risk management is also perceived as chance management. (orig.)

  18. Mapping Urban Heat Demand with the Use of GIS-Based Tools

    Directory of Open Access Journals (Sweden)

    Artur Wyrwa

    2017-05-01

    Full Text Available This article presents a bottom-up approach for calculation of the useful heat demand for space heating and hot water preparation using geo-referenced datasets for buildings at the city level. This geographic information system (GIS based approach was applied in the case study for the city of Krakow, where on the one hand the district heat network is well developed, while on the other hand there are still substantial number of buildings burning solid fuels in individual boilers and stoves, causing air pollution. The calculated heat demand was aggregated in the grid with 100 m × 100 m spatial resolution to deliver the heat map depicting the current situation for 21 buildings types. The results show that the residential buildings, in particular one- and multi-family buildings, have the highest share in overall demand for heat. By combining the results with location of the district heat (DH network, the potential areas in its close vicinity that have sufficient heat demand density for developing the net were pointed out. Future evolution in heat demand for space heating in one-family houses was evaluated with the use of deterministic method employing building stock model. The study lays a foundation for planning the development of the heating system at the city level.

  19. Solar district heating system `Schillerstrasse` in Schwaebisch-Gmuend; Solare Nahwaerme ``Schillerstrasse`` in Schwaebisch Gmuend

    Energy Technology Data Exchange (ETDEWEB)

    Kuebler, R. [Steinbeis-Transferzentrum Energie-, Gebaeude- und Solartechnik, Stuttgart (Germany); Mangold, D. [Stuttgart Univ. (Germany). Inst. fuer Thermodynamik und Waermetechnik

    1998-12-31

    The construction project Schillerstrasse in Schwaebisch-Gmuend was planned and realised by the Siedlungswerk Stuttgart from 1993 until 1996. Like in earlier projects in Ravensburg and Koengen the Siedlungswerk wanted to use new technologies in the field of thermal insulation and heat supply at the construction of this new residential area in order to stay considerably below the former construction standards (WSVO 1982). One part of this energy concept is a large solar plant to support warm water supply. Good experience had been made with flat solar collectors at the three plants in Ravensburg and Koengen. In Schwaebisch-Gmuend vacuum pipe collectors were utilised for the first time. They were the only type of collectors which could be installed on the flat roofs without being visible from the ground. The solar-assisted district heating system was put in operation in May 1996. A new method that controls the system by measuring data acquisition enabled to measure and optimise the thermal performance of the plant. At the beginning of 1998 the plant was modified in order to improve the use of the solar plant. (orig.) [Deutsch] Das Bauvorhaben Schillerstrasse in Schwaebisch Gmuend wurde in den Jahren 1993-1996 vom Siedlungswerk Stuttgart geplant und gebaut. Aehnlich wie bei frueheren Projekten in Ravensburg und Koengen war es das Ziel des Siedlungswerks, in diesem Neubauvorhaben neue Wege beim Waermeschutz und bei der Waermeversorgung der Wohnanlage zu gehen, um den damaligen Baustandard (WSVO 1982) deutlich zu unterschreiten. Ein Element dieses Energiekonzepts ist eine grosse Solaranlage zur Unterstuetzung der Warmwasserbereitung. Nach guten Erfahrungen mit Flachkollektoren in den drei Anlagen in Ravensburg und Koengen wurden in Schwaebisch Gmuend zum ersten Mal Vakuum-Roehrenkollektoren eingesetzt. Fuer die Wahl der Vakuumroehren waren nicht zuletzt die stadtpolitischen Randbedingungen ausschlaggebend, die nur eine von unten nicht sichtbare Aufstellung auf dem

  20. 集中供热系统不同调峰供热方式的技术经济性分析%Technical and Economic Analysis on Different Peak Heating Load Regulation Methods for District Heating System

    Institute of Scientific and Technical Information of China (English)

    张群力; 狄洪发

    2012-01-01

    本文主要分析了分布式调峰供热方式在集中供热系统应用中的技术经济性.通过节能性和经济性对比分析可知,相对于集中调峰供热方式,分布式调峰供热方式可以降低集中供热系统的供热能耗,提高承担基础负荷的集中热源的满负荷运行小时数、提高集中热源的供热效率,同时可以降低一次供热管网的初投资、减少一次供热管网的热损失.%In this paer,the technical and economic analysis on the district heating system with distributed peak heating load regulation method was given out. Compared with the district heating system with centralized peak heating load regulation method, the total heating energy consumption of the district heating system with distributed peak heating load regulation method was reduced. Meanwhile,the operation hours under full load condition and the heating efficiency of the centralized heating source of district heating system were increased,while the initial investiment and heat loss of the primary heating network were decreased.

  1. Geothermal district heating system in Tanggu, Tianjin, China. Chuka Jinmin Kyowakoku Tianjin shi Tanggu deno chinetsu chiiki danbo system

    Energy Technology Data Exchange (ETDEWEB)

    1992-11-01

    The present paper gives an outline of the geothermal district heating system in Tanggu area of Tianjin City. The water temperature of the aquifer in this district is 65-78[degree]C and warm water of 3.1[times]10[sup 6]m[sup 3] is annually used for the wintertime heating of one hundred thousand people. This heating system is operated in two types of subsystems. One is direct and accompanied by emergency boilers and the other is indirect and not accompanied by emergency boilers. The features of this system viewed from the standpoint of comprehensive use are as follows: Used geothermal water is sent to residential houses for bathing service etc. The medical effect of geothermal water is utilized Used geothermal water mixed with unused geothermal water in offered for bathing service. Geothermal water is used for greenhouse operation, farming, etc. Adjustment of flowrate in accordance with temperature is being examined for increasing the use of geothermal resource. As for the economical point, the investment required for this system is larger than the case of boiler heating, but the running cost is smaller. The time for recovering the investment is calculated to be 6.46 years. Corrosion of piping proceeds at the rate of 0.12-0.18mm annually. The lowering of water level was 3m per year. The annual settlement of ground was 52mm in fiscal 1989. 5 figs., 4 tabs.

  2. Design of Low-Energy District Heating System for a Settlement with Low-Energy Buildings

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2011-01-01

    of 55 °C and 25 °C in supply and return line of DH network, respectively with a convenient control of in-house installations (substations). Traditional DH pipe dimensioning methods were based on size searching algorithm in which lowest possible pipe diameter was defined according to the limit of max...... simulation software Termis with simultaneity factor based randomly generated heat demand scenarios for peak winter situation. The simulation results were re-sampled with bootstrapping method and confidence interval of the reliability of the DH system was presented as a result....

  3. Current contributions on the technical thermodynamics, power engineering and district heating supply. Special publication; Aktuelle Beitraege zur technischen Thermodynamik, Energietechnik und Fernwaermeversorgung. Sonderveroeffentlichung

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-03-15

    Within the special publication under consideration, the German Heat and Power Association (Frankfurt (Main), Federal Republic of Germany) presents the following current contributions on the technical thermodynamics, power engineering and district heating supply: (1) Cellular metallic materials for innovative latent heat accumulator technologies (Jens Meinert); (2) Compressed air storage - technology, chances and problems (Rutger Kretschmer); (3) KWK electricity - Identification and evaluation (Matthias Krause); (4) Investigation of the storage ability of district heating grids and implementation into the optimized planning of heat generators (Sebastian Gross); (5) Autarcic thermal densification to the combined heat and power and cooling production? - A fundamental thermodynamic consideration (Torben Moeller); (6) Modelling of cogeneration power plants - Investigation of the transformation opportunity of existing district heating systems in LowEx grids (Martin Rhein); (7) Discrete building model for the dynamic thermohydraulic simulation of district heating (Dominik Haas); (8) Ventilation and degasification of solar power plants (Karin Ruehling); (9) Integral simulation of district heating with TRNSYS-TUD (Steffen Robbi); (10) Theoretical analyses of return temperatures in building heating networks (Andreas Meinzenbach); (11) Municipal energy efficiency as an important contribution to the reduction of greenhouse gas emissions (Matthias Mischke); (12) Investigation of the latent heat storage system PK 6 for use in air-conditioning installations (Sebastian Pinnau); (13) The role of the thermodynamics in the electromobility (Lars Schinke); (14) Flow and heat transfer in cooling channels with methane (Andre Schlott); (15) Numerical calculations of stoves fired with wooden logs (Ulf Senechal); (16) Supply of thermodynamic substance data for working fluids of power engineering (Hans-Joachim Kretzschmar); (17) Cyclic pipe-ground interaction in solar-thermal heat grids

  4. RESEARCH ON THE WATERPOWER COUPLING CHARACTER IN THE DISTRICT HEATING SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    YUAN Liang

    2004-01-01

    In the paper, the concept of the heating network coupling is introduced. A mathematical modal of heating network in water power is established. The coupling degree of the heating network is also calculated trough the liquid increasing matrix

  5. Simple models of district heating systems for load and demand side management and operational optimisation; Simple modeller for fjernvarmesystemer med henblik pae belastningsudjaevning og driftsoptimering

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, B. [Technical Univ. of Denmark, Dept. of Mechanical Engineering, Kgs. Lyngby (Denmark); Larsen, H.V. [Risoe National Lab., System Analysis Dept., Roskilde (DK)

    2004-12-01

    The purpose of this research project has been to further develop and test simple (aggregated) models of district heating (DH) systems for simulation and operational optimization, and to investigate the influence of Load Management and Demand Side Management (DMS) on the total operational costs. The work is based on physical-mathematical modelling and simulation of DH systems, and is a continuation of previous EFP-96 work. In the present EFP-2001 project the goals have been to improve the Danish method of aggregation by addressing the problem of aggregation of pressure losses, and to test the methods on a much larger data set than in the EFP-1996 project. In order to verify the models it is crucial to have good data at disposal. Full information on the heat loads and temperatures not only at the DH plant but also at every consumer (building) is needed, and therefore only a few DH systems in Denmark can supply such data. (BA)

  6. District heating for Switzerland - Project development; Projektentwicklung Fernwaerme Schweiz - Abwaermenutzung aus (de)zentralen Quellen der Industrie und Umwelt (Schlussbericht Projektphase 1)

    Energy Technology Data Exchange (ETDEWEB)

    Oppermann, G. [Verband Fernwaerme Schweiz, Niederrohrdorf (Switzerland); Gutzwiller, S. [Eicher und Pauli AG, Planer fuer Energie- und Gebaeudetechnik, Liestal (Switzerland); Mueller, E. A. [EnergieSchweiz fuer Infrastrukturanlagen, Berne (Switzerland)

    2010-05-15

    This final report for 2010 for the Swiss Federal Office of Energy (SFOE) deals with the achievements of the first phase of a project concerning district heating systems in Switzerland. The Swiss District Heating Association (VFS) aims to initiate district heating projects using a four-phase project. Phase 1 involved the identification of potential projects: Locations for the use of waste heat, environmental heat, wood and biomass were identified. The further phases will involve possible investors, the development of concrete projects and, finally, their realisation. The report describes work to be done, the project organisation, presents basic data needed for the project phases, discusses regional planning aspects, reviews aids such as GPS data and 'excel' spread sheets and geographic aspects. Further topics addressed in the report include results achieved, the search for investors and external communication. The report is completed with recommendations and four appendices.

  7. Technique and economy to prepare biofuelled district heating plants for power production; Teknik och ekonomi foer att foerbereda nya biobraensleeldade vaermeverk foer elproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Steinwall, Pontus; Nystroem, Johan; Nystroem, Olle; Svensson, Sven-Aake [Sycon Energikonsult AB, Malmoe (Sweden)

    1999-10-01

    This report deals with the technique and the economic possibilities to prepare biofuelled district heating plants for power production. In the study three types of plants are examined: (1) 10 MW Heat Boiler with uncooled grate; (2) 50 MW Heat BFB-boiler; (3) 100 MW Heat CFB-boiler. (1) 10 MW boiler with uncooled grate: For this plant we don't recommend any specific preparation to be made with regard to the boiler equipment. Instead the layout of the plant should take into account that a future conversion may involve a complete change of the hot water boiler to a steam boiler and installation of a turbine. This means that the hot water boiler should be placed near a wall and that space should be reserved for a new steam boiler with economiser. A specific preparation that can be recommended is however to invest in a flue gas fan with capacity to overcome the increased pressure loss of the economiser being an integrated part of the new boiler. (2) 50 MW BFB-boiler: If it is believed or the plan is that the plant will be converted to power production within five years, the BFB-boiler should be based on a steam boiler equipped with a superheater from start of the project. If it is likely that conversion will be done later, the plant should still be based on a steam boiler but in this case without the superheater being installed. During the time to conversion the boiler is equipped and operated such that the heat is dissipated as hot water. The reason not to produce steam from start is that a district heating plant working with steam consumes more electricity than one working with hot water. The boiler should be prepared in terms of design and space for installation of the superheater. The extra cost for the preparation is approximately six per cent of the total cost for the whole plant. (3) 100 MW CFB-boiler: The biggest plant with a heat output of 100 MW is here recommend to be prepared for power production if there are plans to do so, without bearing to the time

  8. District heating and cooling systems for communities through power plant retrofit distribution network. Volume 3. Final report, September 1, 1978-May 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-10-01

    This final report of Phase I of the study presents Task 4, Technical Review and Assessment. The most-promising district-heating concept identified in the Phase I study for the Public Service Electric and Gas Company, Newark, New Jersey, is a hot-water system in which steam is extracted from an existing turbine and used to drive a new, small backpressure turbine-generator. The backpressure turbine provides heat for district heating and simultaneously provides additional electric-generating capacity to partially offset the capacity lost due to the steam extraction. This approach is the most-economical way to retrofit the stations studied for district heating while minimizing electric-capacity loss. Nine fossil-fuel-fired stations within the PSE and G system were evaluated for possibly supplying heat for district heating and cooling in cogeneration operations, but only three were selected to supply the district-heating steam. They are Essex, Hudson, and Bergen. Plant retrofit, thermal distribution schemes, consumer-conversion scheme, and consumer-metering system are discussed. Extensive technical information is provided in 16 appendices, additional tables, figures, and drawings. (MCW)

  9. District heating (DH) network design and operation toward a system-wide methodology for optimizing renewable energy solutions (SMORES) in Canada: A case study

    DEFF Research Database (Denmark)

    Dalla Rosa, A.; Boulter, R.; Church, K.

    2012-01-01

    This paper discusses the opportunities and challenges of implementing District Heating (DH) in Canada, with focus on the network design and operation. We selected for case study an urban area in Ottawa. First, we proved that the medium-temperature district heating (MTDH) (70 C Tsupply 90 C) had b...... in Canada. The paper discusses critical issues and quantifies the performance of design concepts for DH supply to low heat density areas. DH is a fundamental energy infrastructure and is part of the solution for sustainable energy planning in Canadian communities.......This paper discusses the opportunities and challenges of implementing District Heating (DH) in Canada, with focus on the network design and operation. We selected for case study an urban area in Ottawa. First, we proved that the medium-temperature district heating (MTDH) (70 C Tsupply 90 C) had...... better energy delivery performance than high-temperature district heating (HTDH) (Tsupply> 100 C), decreasing the heat loss by approximately 40%. The low-temperature networks (Tsupply

  10. Technical, economic and environmental investigation of using district heating to prepare domestic hot water in Chinese multi-storey buildings

    DEFF Research Database (Denmark)

    Zhang, Lipeng; Xia, Jianjun; Thorsen, Jan Eric;

    2016-01-01

    utilizes the industrial waste heat to prepare DHW via the DH network. A building model of a multi-storey building in Beijing was developed to investigate the technical feasibility. An economic evaluation was made using net present value to compare the annualized cost for individual water heaters and flat......The development of DH (District Heating) is an environmentally friendly and energy-efficient strategy in China. Currently, the vast majority of DH systems are SH (Space Heating) only and do not provide DHW (Domestic Hot Water). DHW is mainly produced by individual water heaters due to the cost......-effective issues of the centralized DHW systems. From the perspective of long-term development, DHW produced via DH systems would be more sustainable because DH is an important precondition for an environmental safe use of domestic waste fuels. This paper presents an approach that uses flat stations meanwhile...

  11. Tool for economic and environmental analysis of hybrid plants for district cooling and district heating - 'District cooling 2.0'. Final report and user guide; Vaerktoej til oekonomisk og miljoemaessig analyse af hybridanlaeg til fjernkoeling og fjernvarme. Fjernkoel 2.0. Slutrapport og brugermanual

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-03-15

    The purpose of the tool is to help bring district cooling solutions into consideration by facilitating rapid technical / economic and environmental analysis of district cooling solutions - also with heat pump operation. The tool is a screening tool intended for specific cases with actual data from reality. The tool can analyze the simultaneous production of heat and cooling, and use of storage can make district cooling even more profitable. It is also possible to analyze the importance of flexible electricity and heating prices and see how they can be utilized, including the calculation of the probable prices on heating and cooling, and investments. The tool can make calculations on the following plant types: - Systems with only cooling without cold storage; - Systems with only cooling with cold storage; - Systems with cooling and heating controlled by cooling - with heat storage; - Systems with heating and cooling controlled by heating - with heating and cooling storage; - Systems with cooling and heating with optimized management - with heat storage. The tool can also be used to make general assessments, for example, to analyze the importance of flexible electricity and heating prices of typical district cooling systems, and for that matter, heat pump systems. (LN)

  12. Deadline statistics on October 2006 for district heating cost. Price overview 2006 on district heating; Stichtagsstatistik zum Oktober 2006 fuer Fernwaermekosten. Fernwaerme-Preisuebersicht 2006

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2007-03-15

    Since more than 50 years deadline prices of public utilities are imposed by the AGFW, last at 1st October 2006. As well the federation of heat- and cogeneration economy relates to typical supply cases in different dimensions representing different user behaviour. In addition to this cases of purchase and utilization periods of a development to efficient energy consumption are adapted. (GL)

  13. Model based monitoring of traffic noise in an urban district

    NARCIS (Netherlands)

    Eerden, F. van der; Graafland, F.; Wessels, P.; Segers, A.; Salomons, E.

    2014-01-01

    Noise control for an urban district starts by understanding the actual noise situation. A correct understanding is needed to take appropriate and cost efficient measures. For a noise burdened urban district, surrounded by road and rail traffic, the traffic noise as well as the annoyance has been mea

  14. Køling ved hjælp af fjernvarme (Using District Heating for Cooling)

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard

    1999-01-01

    The theoretical basic using heat to produce cooling is explained by combining two Carnot processes. Ejector and Absoption cycles, which are two pratical processe using heat, are explained. For absorption cycles different layout is shown using low temperature heat source. It is shown how a high...... change in the heat source temperature can be realized.....

  15. Integrated Temperature Sensors based on Heat Diffusion

    NARCIS (Netherlands)

    Van Vroonhoven, C.P.L.

    2015-01-01

    This thesis describes the theory, design and implementation of a new class of integrated temperature sensors, based on heat diffusion. In such sensors, temperature is sensed by measuring the time it takes for heat to diffuse through silicon. An on-chip thermal delay can be determined by geometry and

  16. Load Prediction in District Heating Systems with Regard to Scenarios and Uncertainties in Weather; Lastprognoser foer fjaerrvaerme med haensyn till scenarier och osaekerheter i vaedret

    Energy Technology Data Exchange (ETDEWEB)

    Hedberg, Martin; Koppers, Gijs [Meteopolaris AB, Nacka (Sweden)

    2011-11-15

    The report shows, by means of load calculations on ensemble weather forecasts and subsequent production planning, that by a better optimization of the operation of district heating plants the costs of production of heat and electricity can be reduced. During a fifth of the time the saving potential is 5% or more.

  17. High-temperature pretreatment of biogas substrate by using district heating to increase the biogas production; Hoegtemperaturfoerbehandling av biogassubstrat med fjaerrvaerme foer oekad biogasproduktion

    Energy Technology Data Exchange (ETDEWEB)

    Del Pilar Castillo, Maria; Ascue, Johnny [JTI, Uppsala (Sweden); Olsson, Marcus; Henriksson, Gunilla; Nordman, Roger [SP, Boraas (Sweden)

    2011-12-15

    In this study, we have shown that pre-heating sludge from a waste water treatment plant can give a higher biogas production rate. However, pretreatment showed no effect on substrate from a biogas plant at the conditions tested in this study. The study has also shown that there is potential of using district heating in the biogas industry for thermal pretreatment of sludge.

  18. District heating and cooling systems for communities through power plant retrofit distribution network. Final report, September 1, 1978-May 31, 1979

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-10-01

    This volume presents information on the institutional factors, i.e., legal and regulatory aspects, a preliminary economic analysis, and a proposal for future studies on retrofitting existing thermal power plants so that they can supply heat for district heating and cooling systems for communities. (LCL)

  19. Incorporating sustainable development considerations into energy sector decision-making: Malmoe Flintraenen district heating facility case study

    Energy Technology Data Exchange (ETDEWEB)

    Bardouille, P. [International Institute for Industrial Environmental Economics, Lund University, Lund (Sweden); Koubsky, J. [Kalovy Vary (Czech Republic)

    2000-08-01

    The paper introduces an on-going doctoral research study aimed at facilitating the operationalisation of sustainable energy systems. The study focuses upon the analysis of existing and development of new methods for the incorporation of socio-environmental considerations into large-scale investment decision-making in the energy sector. The final output of the research study, to be completed by the end of 2001, will be a Framework for Sustainable Energy Sector Investment Analysis and Decision Support. The Framework will be designed for application by energy companies in decision-making processes concerning the selection of new power generation alternatives. In order to broadly identify decision-making parameters applied to energy sector decision processes, primary data collection for the study involves the retrospective analysis of decision cases. The results of one portion of information gathering undertaken as part of the aforementioned data collection are presented in the paper. A retrospective case study analysis was carried out on an investment decision-making process concerning the Flintraenen biomass-based district heating plant in southern Sweden. To analyse the case study data, an analytical module was developed. Examination of the Flintraenen case using the analytical module revealed several weaknesses in the decision-making methods applied to the planning of the facility, originating primarily from the incorporation of only a limited number of decision parameters or considerations into investment calculations. Furthermore, analysis showed that, had appropriate socio-environmental decision-support methods been incorporated into the decision process, considerable financial and internal environmental costs associated with the facility could have been avoided, and environmental risk linked to its operation decreased. Lessons learned from the Flintraenen case will be utilised as input into the ongoing identification and development of parameters considered as

  20. Status seminar `98: Solar-supported district heating with seasonal heat storage. Status report `98; Status-Seminar `98: Solarunterstuetzte Nahwaermeversorgung - Saisonale Waermespeicherung. Statusbericht `98

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    This status report refers to the BMBF (Federal Ministry for Education, Science, Research and Technology) status seminar: Solar-assisted district heat supply - seasonal heat storage that took place in Neckarsulm on 19th and 20th May. 1998. The report contains the reference papers and the status reports of all projects supported under the Ministry`s SOLARTHERMIE programme that have already been finished or are still running. (orig.) [Deutsch] Der vorliegende Statusbericht wird anlaesslich des BMBF-Statusseminars: Solarunterstuetzte Nahwaermeversorgung - Saisonale Waermespeicherung am 19. und 20. Mai 1998 in Neckarsulm herausgegeben. Der Bericht enthaelt neben den Tagungsbeitraegen auch die Sachstandsberichte aller Projekte, die zu diesem Thema in den letzten Jahren von BMBF in dem Programm SOLARTHERMIE-2000 bereits abgeschlossen wurden oder z.Zt. gefoerdert werden. (orig.)

  1. Solar heating and hot water system installed at Southeast of Saline, Unified School District 306, Mentor, Kansas

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-01

    A cooperative agreement was negotiated in April 1978 for the installation of a space and domestic hot water system at Southeast of Saline, Kansas Unified School District 306, Mentor, Kansas. The solar system was installed in a new building and was designed to provide 52 percent of the estimated annual space heating load and 84 percent of the estimated annual potable hot water requirement. The collectors are liquid flat plate. They are ground-mounted and cover a total area of 5125 square feet. The system will provide supplemental heat for the school's closed-loop water-to-air heat pump system and domestic hot water. The storage medium is water inside steel tanks with a capacity of 11,828 gallons for space heating and 1,600 gallons for domestic hot water. This final report, which describes in considerable detail the solar heating facility, contains detailed drawings of the completed system. The facility was declared operational in September 1978, and has functioned successfully since.

  2. High resolution heat atlases for demand and supply mapping

    Directory of Open Access Journals (Sweden)

    Bernd Möller

    2014-02-01

    Full Text Available Significant reductions of heat demand, low-carbon and renewable energy sources, and district heating are key elements in 100% renewable energy systems. Appraisal of district heating along with energy efficient buildings and individual heat supply requires a geographical representation of heat demand, energy efficiency and energy supply. The present paper describes a Heat Atlas built around a spatial database using geographical information systems (GIS. The present atlas allows for per-building calculations of potentials and costs of energy savings, connectivity to existing district heat, and current heat supply and demand. For the entire building mass a conclusive link is established between the built environment and its heat supply. The expansion of district heating; the interconnection of distributed district heating systems; or the question whether to invest in ultra-efficient buildings with individual supply, or in collective heating using renewable energy for heating the current building stock, can be based on improved data.

  3. User manual for AQUASTOR: a computer model for cost analysis of aquifer thermal-energy storage oupled with district-heating or cooling systems. Volume II. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Huber, H.D.; Brown, D.R.; Reilly, R.W.

    1982-04-01

    A computer model called AQUASTOR was developed for calculating the cost of district heating (cooling) using thermal energy supplied by an aquifer thermal energy storage (ATES) system. the AQUASTOR Model can simulate ATES district heating systems using stored hot water or ATES district cooling systems using stored chilled water. AQUASTOR simulates the complete ATES district heating (cooling) system, which consists of two prinicpal parts: the ATES supply system and the district heating (cooling) distribution system. The supply system submodel calculates the life-cycle cost of thermal energy supplied to the distribution system by simulating the technical design and cash flows for the exploration, development, and operation of the ATES supply system. The distribution system submodel calculates the life-cycle cost of heat (chill) delivered by the distribution system to the end-users by simulating the technical design and cash flows for the construction and operation of the distribution system. The model combines the technical characteristics of the supply system and the technical characteristics of the distribution system with financial and tax conditions for the entities operating the two systems into one techno-economic model. This provides the flexibility to individually or collectively evaluate the impact of different economic and technical parameters, assumptions, and uncertainties on the cost of providing district heating (cooling) with an ATES system. This volume contains all the appendices, including supply and distribution system cost equations and models, descriptions of predefined residential districts, key equations for the cooling degree-hour methodology, a listing of the sample case output, and appendix H, which contains the indices for supply input parameters, distribution input parameters, and AQUASTOR subroutines.

  4. Køling ved hjælp af fjernvarme (Using District Heating for Cooling)

    DEFF Research Database (Denmark)

    Knudsen, Hans Jørgen Høgaard

    1999-01-01

    The theoretical basic using heat to produce cooling is explained by combining two Carnot processes. Ejector and Absoption cycles, which are two pratical processe using heat, are explained. For absorption cycles different layout is shown using low temperature heat source. It is shown how a high...

  5. Expieriences On Low-Temperature District Heating In Lystrup – Denmark

    DEFF Research Database (Denmark)

    Thorsen, Jan Eric; Christiansen, Christian Holm; Brand, Marek

    2011-01-01

    reduction of heat consumption for individual buildings. This means ratio between net work heat loss and heat consumption in buildings will become even more important in future. To address this challenge low-temperature DH network concept is analysed and tested in real scale. This paper describes main...

  6. Long-term modelling of Carbon Capture and Storage, Nuclear Fusion, and large-scale District Heating

    DEFF Research Database (Denmark)

    Grohnheit, Poul Erik; Korsholm, Søren Bang; Lüthje, Mikael

    2011-01-01

    Among the technologies for mitigating greenhouse gasses, carbon capture and storage (CCS) and nuclear fusion are interesting in the long term. In several studies with time horizon 2050 CCS has been identified as an important technology, while nuclear fusion cannot become commercially available...... on nuclear fusion and the Pan European TIMES model, respectively. In the next decades CCS can be a driver for the development and expansion of large-scale district heating systems, which are currently widespread in Europe, Korea and China, and with large potentials in North America. If fusion will replace...... fossil fuel power plants with CCS in the second half of the century, the same infrastructure for heat distribution can be used which will support the penetration of both technologies. This paper will address the issue of infrastructure development and the use of CCS and fusion technologies using...

  7. Implementing a Student-Based Funding Policy: Considerations for School Districts

    Science.gov (United States)

    Shambaugh, Larisa S.; Chambers, Jay G.

    2009-01-01

    As education budgets continue to tighten, increased attention is focused on how school districts can best distribute existing funds to schools and how schools can best use these funds. Student-based funding (SBF)--sometimes referred to as a weighted student formula--is one approach that school districts have taken during the past decade. SBF…

  8. Miscellaneous investigations. Subreport 3; CO{sub 2}-reductions in low-energy buildings and communities by implementation of low-temperature district heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Brand, M. (DTU-BYG, Kgs. Lyngby (Denmark)); Kaarup Olsen, P. (COWI A/S, Kgs. Lyngby (Denmark))

    2011-05-15

    -16%. Residence buildings account for the largest part of the heat consumption, but also a large number of industry and commercial buildings are supplied with DH. Lowering the DH temperature from 80/40 deg. C to 55/30 deg. C can reduce existing network heat loss by about 35%. With an optimal pipe system, the saving potential can be increased to 50-75%. In total for Denmark, the reduction potential is assessed to be up to about 1,000,000 tonnes CO{sub 2} per year, corresponding to about 1/5 of the total yearly emission for DH. The third chapter reports investigations on the possibility of supplying existing typical buildings built in the 1970s with LTDH with a supply temperature around 50 deg. C. It is shown that basic renovation measures such as a change of the windows allow decreasing the maximum supply temperature needed for space heating (SH) system to 50 deg. C for most of the heating season. A transition of all existing buildings to LTDH is also connected with change of DH in-house substations. DH in-house substations equipped with DHW storage tank should be changed if the DH supply temperature is reduced below 60 deg. C at any time during a year (because of Legionella risk), and GVV units should be changed if the supply temperature drops below 55 deg. C. It is suggested to replace all traditional substations by new types specially designed for LTDH. Moreover, if the domestic hot water (DHW) system is operated with DHW temperature below 55 deg. C, maximal volume of water in all DHW feeding pipes and circulation pipes is limited to 3 litres. In the next chapter examples are shown of typical heat demands and peak power for DHW heating and SH in low-energy single-family houses as well as in existing typical singlefamily houses from the 1970's. The reported peak power for individual houses is later used as a base for evaluation of reduction of peak power in the district heating network (DHN). This report look into optimization of the FVB unit, where the needed DHW priority

  9. Method to investigate and plan the application of low temperature district heating to existing hydraulic radiator systems in existing buildings

    DEFF Research Database (Denmark)

    Tunzi, Michele; Østergaard, Dorte Skaarup; Svendsen, Svend;

    2016-01-01

    the required logarithmic mean temperature difference (LMTD) for a low temperature heating system. The results of the analysis are presented as the average reduction of LMTD over the heating season compared to the base case design conditions. Two scenarios were investigated based on the assumption of a likely...

  10. Lunar base heat pump, phase 1

    Science.gov (United States)

    Goldman, Jeffrey H.; Harvey, A.; Lovell, T.; Walker, David H.

    1994-01-01

    This report describes the Phase 1 process and analysis used to select a refrigerant and thermodynamic cycle as the basis of a vapor compression heat pump requiring a high temperature lift, then to perform a preliminary design to implement the selected concept, including major component selection. Use of a vapor compression heat pump versus other types was based on prior work performed for the Electric Power Research Institute. A high lift heat pump is needed to enable a thermal control system to remove heat down to 275 K from a habitable volume when the external thermal environment is severe. For example, a long-term lunar base habitat will reject heat from a space radiator to a 325 K environment. The first step in the selection process was to perform an optimization trade study, quantifying the effect of radiator operating temperature and heat pump efficiency on total system mass; then, select the radiator operating temperature corresponding to the lowest system mass. Total system mass included radiators, all heat pump components, and the power supply system. The study showed that lunar night operation, with no temperature lift, dictated the radiator size. To operate otherwise would require a high mass penalty to store power. With the defined radiation surface, and heat pump performances assumed to be from 40 percent to 60 percent of the Carnot ideal, the optimum heat rejection temperature ranged from 387 K to 377 K, as a function of heat pump performance. Refrigerant and thermodynamic cycles were then selected to best meet the previously determined design conditions. The system was then adapted as a ground-based prototype lifting temperature to 360 K (versus 385 K for flight unit) and using readily available commercial-grade components. Over 40 refrigerants, separated into wet and dry compression behavioral types, were considered in the selection process. Refrigerants were initially screened for acceptable critical temperature. The acceptable refrigerants were

  11. Solar-assisted district heating system - Scientific study. Solar-assisted district heating system with long-term thermal storage in Friedrichshafen-Wiggenhausen and Hamburg-Bramfeld.. Results of the first year of operation; Solar unterstuetzte Nahwaermeversorgung - Wissenschaftliches Begleitprogramm. Solare Nahwaermeversorgung mit Langzeitwaermespeicher in Friedrichshafen-Wiggenhausen und Hamburg-Bramfeld. Ergebnisse des ersten Betriebsjahres

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, M.E.; Mahler, B.; Hahne, E. [Stuttgart Univ. (Germany). Inst. fuer Thermodynamik und Waermetechnik

    1998-12-31

    The first two pilot plants for solar district heating with seasonal thermal energy storage were put in operation in October 1996. Both projects were initiated by the Institute for Thermodynamics and Thermal Energy Technology (ITW) of the University of Stuttgart that also provided scientific support up to the present. This report presents the results of the first two years of operation of both plants. Both solar plants have been operated without any major problems. The solar energy yield in the first year of operation has only been reduced by the unsatisfactory operation of the heating grid. The most important step towards optimising the plants is the adjustment of the internal heating systems and thus the reduction of the heating temperatures which are currently too high. Based on subject pre-conditions the results projected for the first pilot plants for solar district heating and long-term thermal energy storage will be reached in the following years of operation. (orig.) [Deutsch] Im Oktober 1996 gingen die ersten beiden Pilotanlagen zur solaren Nahwaermeversorgung mit saisonaler Waermespeicherung in Betrieb. Beide Projekte wurden vom Institut fuer Thermodynamik und Waermetechnik (ITW), Universitaet Stuttgart initiiert und ueber die gesamte bisherige Laufzeit wissenschaftlich begleitet. Die Ergebnisse des ersten Betriebsjahres der beiden Anlagen sind in diesem Bericht zusammengestellt. In beiden Faellen funktionieren die Solaranlagen ohne grosse Probleme. Die solaren Ertraege wurden im ersten Betriebsjahr noch durch die unzureichende Betriebsweise der Heiznetze gemindert. Wichtigster Ansatzpunkt fuer eine Optimierung der Anlagen ist die Einregulierung der hausinternen Heizungssysteme und damit die Absenkung der derzeit noch zu hohen Heiznetztemperaturen. Unter dieser Voraussetzung werden die vorausgesagten Ergebnisse fuer die ersten Pilotanlagen zur solaren Nahwaerme mit Langzeit-Waermespeicher in den naechsten Betriebsjahren erreicht werden. (orig.)

  12. The geothermal potential of the Campania volcanic district and new heat exchanger technologies for exploitation of highly urbanised areas.

    Science.gov (United States)

    Carlino, S.; Somma, R.; Troiano, A.; Di Giuseppe, M. G.; Troise, C.; De Natale, G.

    2012-04-01

    The geothermal research in Campania region (Italy), started since the 1930, and continued until the '80 by the SAFEN, ENEL and AGIP companies. Such exploration activity highlighted that most of the volcanic districts of the Campania Region have a very high geothermal gradient and heat flow. In particular, inside the Campi Flegrei caldera and at Ischia island the geothermal gradient measured inside the deep wells reaches temperatures above 100° C between few tens and few hundreds of metres of depth, while the heat flow varies between 120-160 mWm-2 at Agnano and Mofete (Campi Flegrei main drill sites) to more than 500 mWm-2 at Ischia island (south-western sector). A general review of the available literature data (temperature at depth, stratigraphic sections, logs etc.) of the deep wells (down to 3 km b.s.l.) allowed us to quantify the geothermal potential (thermal and electric) of such district. The geothermal potential is about 6 GWy for the Campi Flegrei (Mofete and S. Vito sectors) and 11 GWy for the Ischia island (south-western sector) showing a geothermal reservoir with water and vapour dominant respectively. This results in strong potential interest for economic exploitation of the geothermal resource, both in the range of low-medium enthalpy at few hundreds of meters depth and of high enthalpy at depths of 1-2 km. In this study we try to model the effectiveness of new technologies of boreholes heat exchangers, which would allow to avoid fluid withdrawal, then strongly decreasing the environmental impact. The proposed technology consists of a double-pipe placed in a borehole heat exchange that can work coupled with an ORC. The two pipes, one inside the other, are located in the well in order to transfer the thermal energy to the working fluid during the descent in the external pipe and then go back through the internal pipe properly isolated. We propose a complete design of the borehole heat exchangers. The design activity is performed on a theoretical basis

  13. A comparison of different methods for in-situ determination of heat losses form district heating pipes

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Benny [Technical Univ. of Denmark, Dept. of Energy Engineering (Denmark)

    1996-11-01

    A comparison of different methods for in-situ determination of heat losses has been carried out on a 273 mm transmission line in Copenhagen. Instrumentation includes temperature sensors, heat flux meters and an infrared camera. The methods differ with regard to time consumption and costs of applying the specific method, demand on accuracy of temperature measurements, sensitivity to computational parameters, e.g. the thermal conductivity of the soil, response to transients in water temperature and the ground, and steady state assumptions in the model used in the interpretation of the measurements. Several of the applied methods work well. (au)

  14. AGFW. Main report of the district heat supply 1997; AGFW. Hauptbericht der Fernwaermeversorgung 1997. Technische Daten zur Fernwaermeversorgung in Deutschland 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-11-01

    A total of 245 district heat supply companies contributed to the main report of the district heat supply industry. 156 of which are from the old federal states to include Berlin and 89 companies are from the new federal states. The division of the companies into each federal state is represented. (orig.) [Deutsch] Am Hauptbericht der Fernwaermeversorgung beteiligten sich insgesamt 245 Fernwaermeversorgungsunternehmen (FVU), davon 156 Unternehmen aus den alten Bundeslaendern einschliesslich Berlin und 89 Unternehmen aus den neuen Bundeslaendern. Berichtet wird ueber die Fernwaermeerzeugung, -verteilung sowie Anschluss- und Kundenanlagen. (orig.)

  15. AGFW. Main report of the district heat supply 1999; AGFW. Hauptbericht der Fernwaermeversorgung 1999. Technische Bestands- und Veraenderungsdaten zur Fernwaermeversorgung in Deutschland 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    A total of 226 district heat supply companies contributed to the main report of the district heat supply industry. 142 of which are from the old federal states to include Berlin and 84 companies are from the new federal states. The division of the companies into each federal state is represented. (orig.) [German] Am Hauptbericht der Fernwaermeversorgung beteiligten sich insgesamt 226 Fernwaermeversorgungsunternehmen (FVU), davon 142 Unternehmen aus den alten Bundeslaendern einschliesslich Berlin und 84 Unternehmen aus den neuen Bundeslaendern. Berichtet wird ueber die Fernwaermeerzeugung, -verteilung sowie Anschluss- und Kundenanlagen. (orig.)

  16. A comparison of aggregated models for simulation and operational optimisation of district heating networks

    DEFF Research Database (Denmark)

    Larsen, Helge V.; Bøhm, Benny; Wigbels, M.

    2004-01-01

    as a test case. For the 23 substations in Ishoej, heat loads and primary and secondary supply and return temperatures were available every 5 min for the period December 19–24, 2000. The accuracy of the aggregation models has been documented as the errors in heat production and in return temperature...

  17. Life Cycle Assessment of Miscanthus as a Fuel Alternative in District Heat Production

    DEFF Research Database (Denmark)

    Parajuli, Ranjan; Dalgaard, Tommy; Nguyen, T Lan T

    2013-01-01

    ) plant. Alternatively, we have simulated the combustion process of Miscanthus in a boiler, where only heat is produced. For NG similar scenarios are examined. Life Cycle Assessment (LCA) in relation to 1 MJ of heat production with Miscanthus fired in a CHP would lead to a Global Warming Potential (GWP...

  18. Case Studies in Low-Energy District Heating Systems: Determination of Dimensioning Methods for Planning the Future Heating Infrastructure

    DEFF Research Database (Denmark)

    Tol, Hakan; Nielsen, Susanne Balslev; Svendsen, Svend

    , results about the optimal network layout and substation type for low-energy DH systems are also pointed out regarding to this case study. A second case study, included in this paper, focuses on technical and economical aspects of replacing natural gas heating system to low-energy DH system in an existing...

  19. Miscellaneous investigations. Subreport 3; CO{sub 2}-reductions in low-energy buildings and communities by implementation of low-temperature district heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Brand, M. (DTU-BYG, Kgs. Lyngby (Denmark)); Kaarup Olsen, P. (COWI A/S, Kgs. Lyngby (Denmark))

    2011-05-15

    -16%. Residence buildings account for the largest part of the heat consumption, but also a large number of industry and commercial buildings are supplied with DH. Lowering the DH temperature from 80/40 deg. C to 55/30 deg. C can reduce existing network heat loss by about 35%. With an optimal pipe system, the saving potential can be increased to 50-75%. In total for Denmark, the reduction potential is assessed to be up to about 1,000,000 tonnes CO{sub 2} per year, corresponding to about 1/5 of the total yearly emission for DH. The third chapter reports investigations on the possibility of supplying existing typical buildings built in the 1970s with LTDH with a supply temperature around 50 deg. C. It is shown that basic renovation measures such as a change of the windows allow decreasing the maximum supply temperature needed for space heating (SH) system to 50 deg. C for most of the heating season. A transition of all existing buildings to LTDH is also connected with change of DH in-house substations. DH in-house substations equipped with DHW storage tank should be changed if the DH supply temperature is reduced below 60 deg. C at any time during a year (because of Legionella risk), and GVV units should be changed if the supply temperature drops below 55 deg. C. It is suggested to replace all traditional substations by new types specially designed for LTDH. Moreover, if the domestic hot water (DHW) system is operated with DHW temperature below 55 deg. C, maximal volume of water in all DHW feeding pipes and circulation pipes is limited to 3 litres. In the next chapter examples are shown of typical heat demands and peak power for DHW heating and SH in low-energy single-family houses as well as in existing typical singlefamily houses from the 1970's. The reported peak power for individual houses is later used as a base for evaluation of reduction of peak power in the district heating network (DHN). This report look into optimization of the FVB unit, where the needed DHW priority

  20. A new calculation method for profiled T pieces in the district heating; Neue Berechnungsmethode fuer ausgehalste T-Stuecke in der Fernwaerme

    Energy Technology Data Exchange (ETDEWEB)

    Besedin, Eugen; Schleyer, Andreas [GEF Ingenieur AG, Leimen (Germany); Lorch, Jochen; Hartmann, Roland [TUEV SUED Industrie Service GmbH, Stuttgart (Germany)

    2012-07-01

    Profiled T-pieces in the district heating are technically and economically an optimal solution. Their verification by calculation is conservative in the case of underground high-temperature pipes with extremely high axial forces due to friction. This mathematical proof requires a parallel branching or enables only a short branching lengths at T-junctions. In order to take advantage of profiled T-pieces in the planning of plastic casing pipe systems, parameterized analyzes based on the finite-element-method (FEM) were performed, evaluated and transmitted to the entire nominal size combinations. The resulting method of calculation enables a realistic use of the FEM results in the framework programs. Almost 50% lower material utilizations result in comparison to a conventional fatigue analysis.

  1. The underground heat storage for solar-assisted district heating in Neckarsulm. First measuring results; Der Erdsonden-Waermespeicher fuer die solarunterstuetzte Nahwaermeversorgung in Neckarsulm. Erste Messergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Seiwald, H.; Hahne, E. [Stuttgart Univ. (Germany). Inst. fuer Thermodynamik und Waermetechnik

    1998-12-31

    A solar-assisted district heating system with seasonal underground heat storage is currently under construction in Neckarsulm (Baden-Wurttemberg). In the new residential area approximately 1,300 flats are going to be built during the next years. The overall energy demand (hot water and space heating) is supposed to be covered by 50% with solar energy. During the first phase the project will be subsidised in the frame of the BMBF programme `Solarthermie 2000, Teilprogramm III`. A solar plant consisting of 2,700 square metres of collectors, a buffer tank (100 cubic metre) and an underground heat storage with a volume of approx. 20,000 cubic metres will be constructed by the end of 1998. It will be the first plant in Germany where thermal energy generated of solar energy is stored at high temperatures (up to 80 C) directly in the earth and utilised without a heat pump. (orig.) [Deutsch] In Neckarsulm (Baden-Wuerttemberg) befindet sich derzeit eine solar unterstuetzte Nahwaermeversorgung mit saisonalem Endsonden-Waermespeicher im Aufbau. Im Neubaugebiet Amorbach werden in den naechsten Jahren rund 1300 Wohneinheiten entstehen, deren Gesamtwaermebedarf (Warmwasser und Raumheizung) zu rund 50% mit Sonnenenergie gedeckt werden soll. In der ersten Phase wird das Projekt im Rahmen des BMBF-Programms `Solarthermie 2000, Teilprogramm III` gefoerdert. Bis Ende 1998 wird eine Solaranlage bestehend aus 2.700 m{sup 2} Kollektoren, einem Pufferspeicher (100 m{sup 3}) und einem Endsonden-Waermespeicher mit einem Volumen von ca. 20.000 m{sup 3} erstellt. Damit wird in Deutschland erstmalig eine Anlage realisiert, bei der solar erzeugte Waerme auf hohem Temperaturniveau (bis zu 80 C) direkt im Erdreich gespeichert und ohne Waermepumpe genutzt werden soll. (orig.)

  2. 2008 Northwest Florida Water Management District (NWFWMD) Lidar: Eglin Air Force Base, Walton County, FL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the summer of 2008, the Northwest Florida Water Management District collected lidar data over a portion of Walton County, FL (Eglin Air force Base) to support...

  3. 2008 Northwest Florida Water Management District Lidar: Eglin Air Force Base, Walton County, FL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the summer of 2008, the Northwest Florida Water Management District collected lidar data over a portion of Walton County, FL (Eglin Air force Base) to support...

  4. Willow as fuel for district heating. Experiences from test combustion; Energipil som braendsel til fjernvarme - Erfaringsindsamling fra testfyringer

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Joergen

    2012-10-15

    The project has been a study of the fuel characteristics of willow chips. The study was carried out on Trustrup-Lyngby Heating Plant and Assens District Heating Plant in the period 2011-12. Operating experiences were collected from the two plants. Furthermore, yield and crop data were collected from suppliers of willow chips to Assens District Heating Plant, and the analysis of particle size distribution of the willow chips is carried out. The collected data on yield and particle size distribution are compared with results from previous studies. The project has shown that willow chips generally are a suitable and attractive fuel in wood-fired heat and power plants. The plants are very aware of quality of willow chips and want chips with coarse structure. Furthermore, there is the wish that water content of willow chips are on par with the moisture content of wood chips, i.e. around 30-40%; woodchips are the vast majority of the chips used in the plants. Wood chips produced from fresh willow shoots with chopper will typically have a moisture content of 50-60 %. Such ''wet'' chips will of some plants be deselected during winter, where there is a requirement of safe and high boiler output. Other plants will simply mix the ''wet'' willow chips with other, drier types of chips and can use it almost all the year. If the willow shoots are harvested as branches, which subsequently are allowed to dry for a period before chipping, willow chips can be produced with a moisture content that is in line with what is typical in wood chips. Analysis of particle size distribution shows that willow chips harvested with a cutting machine usually can meet the requirements for quality classes ''fine'', ''medium'' and ''coarse''. An account of the harvested yields of willow among the growers who supplied willow chips to Assens Heating Plant, showed a relatively low yield of 5.1 tonnes dry

  5. Willow as fuel for district heating. Experiences from test combustion; Energipil som braendsel til fjernvarme - Erfaringsindsamling fra testfyringer

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, Joergen

    2012-10-15

    The project has been a study of the fuel characteristics of willow chips. The study was carried out on Trustrup-Lyngby Heating Plant and Assens District Heating Plant in the period 2011-12. Operating experiences were collected from the two plants. Furthermore, yield and crop data were collected from suppliers of willow chips to Assens District Heating Plant, and the analysis of particle size distribution of the willow chips is carried out. The collected data on yield and particle size distribution are compared with results from previous studies. The project has shown that willow chips generally are a suitable and attractive fuel in wood-fired heat and power plants. The plants are very aware of quality of willow chips and want chips with coarse structure. Furthermore, there is the wish that water content of willow chips are on par with the moisture content of wood chips, i.e. around 30-40%; woodchips are the vast majority of the chips used in the plants. Wood chips produced from fresh willow shoots with chopper will typically have a moisture content of 50-60 %. Such ''wet'' chips will of some plants be deselected during winter, where there is a requirement of safe and high boiler output. Other plants will simply mix the ''wet'' willow chips with other, drier types of chips and can use it almost all the year. If the willow shoots are harvested as branches, which subsequently are allowed to dry for a period before chipping, willow chips can be produced with a moisture content that is in line with what is typical in wood chips. Analysis of particle size distribution shows that willow chips harvested with a cutting machine usually can meet the requirements for quality classes ''fine'', ''medium'' and ''coarse''. An account of the harvested yields of willow among the growers who supplied willow chips to Assens Heating Plant, showed a relatively low yield of 5.1 tonnes dry

  6. Solar-assisted biomass-district heating: projects in Austria and operational data; Solarunterstuetzte Biomasse-Fernwaermeversorgung: Projekte in Oesterreich und Betriebsdaten

    Energy Technology Data Exchange (ETDEWEB)

    Faninger, G. [Institut fuer Interdisziplinaere Forschung und Fortbildung der Universitaeten Klagenfurt, Innsbruck und Wien (IFF), Klagenfurt (Austria)

    1998-12-31

    In recent years small-volume biomass district heating systems (district heat grids) have attracted increasing interest in Austria. By the end of 1997 some 359 biomass-district heating systems with an overall capacity of approximately 483 MW were in operation. If a biomass-district heating plant and a solar plant are combined the solar plant can supply most of the heat required outside the heating season. At present Austria runs 12 solar-assisted biomass-district heating grids with collector areas between 225 square metres and 1,250 square metres. In order to run these biomass-district heating systems in an economically and technically efficient way it is necessary to assure high quality in terms of planning, construction and operation. A list of criteria is set up on the basis of first operational data in order to evaluate energy efficiency and economic performance. These criteria should be applied in order to ensure that energy, environment and economy are equally considered in the planning and construction of solar-assisted biomass-district heating plants. They should also be helpful for the approval procedures of projects. (orig.) [Deutsch] Kleinraeumige Biomasse-Fernwaermeanlagen (Nahwaermenetze) fanden in den letzten Jahren zunehmendes Interesse in Oesterreich. So waren Ende 1997 insgesamt 359 Biomasse-Fernwaermeanlagen mit einer installierten Gesamtleistung von etwa 483 MW in Betrieb. Die Kombination einer Biomasse-Fernwaermeanlage mit einer Solaranlage bringt den Vorteil, dass die Waermebereitstellung ausserhalb der Heizsaison zu einem hohen Anteil ueber die Solaranlage vorgenommen werden kann. Derzeit werden in Oesterreich 12 solarunterstuetzte Biomasse-Nahwaermenetze mit Kollektorflaechen von 225 m{sup 2} bis 1.250 m{sup 2} betrieben. Um einen moeglichst effizienten und damit auch wirtschaftlichen Betrieb von solarunterstuetzten Biomasse-Fernwaermeanlagen zu gewaehrleisten, werden hohe Anforderungen an Planung, Ausfuehrung und Betrieb gestellt. Auf der

  7. Solar district heating and seasonal heat storage - state of the art; Solare Nahwaerme und Saisonale Waermespeicherung - Stand der Technik

    Energy Technology Data Exchange (ETDEWEB)

    Pfeil, M.; Hahne, E. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany). Geschaeftsbereich Solarthermische Energietechnik; Lottner, V. [BEO Biologie, Energie Oekologie, Juelich (Germany); Schulz, M. [Stuttgart Univ. (Germany). Inst. fuer Thermodynamik und Waermetechnik

    1998-02-01

    Solar energy technology becomes more and more important for space and water heating of residential buildings. Compared to small systems for single-family houses, the specific investment cost of big solar plants is lower and a higher contribution of solar energy can be achieved. In central solar heating plants with seasonal storage (CSHPSS), more than 50% of the total heat demand of residential areas can be covered by solar energy. The first pilot plants for CSHPSS are operating in Germany since 1996. The first results of the accompanying monitoring program show good agreement between calculated and actual solar contribution. (orig.) [Deutsch] Die Nutzung solarer Niedertemperaturwaerme zur Brauchwassererwaermung und zur Beheizung von Wohngebaeuden erfaehrt in Deutschland ein immer groesseres Interesse. Solare Grossanlagen haben gegenueber solaren Kleinanlagen den Vorteil, dass mit geringeren Investitions- und Waermekosten groessere Anlagenertraege erzielt werden koennen. In Verbindung mit saisonaler Waermespeicherung erreichen solare Grossanlagen Deckungsanteile von 50% und darueber am Gesamtwaermebedarf von Wohnsiedlungen. Die ersten Pilotanlagen zur solaren Nahwaerme mit saisonalem Waermespeicher gingen 1996 in Betrieb und werden derzeit detailliert vermessen. Erste Ergebnisse zeigen, dass die vorausberechneten Werte fuer den Jahresenergieertrag erreicht werden koennen. (orig.)

  8. Modular compact house substations for district heating with capacities of up to 1 MW. Modulare Fernwaermekompakthausstation bis 1 MW Leistung

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, F. (Mannheimer Versorgungs- und Verkehrsgesellschaft mbH (MVV), Mannheim (Germany)); Dausch, H.J. (Mannheimer Versorgungs- und Verkehrsgesellschaft mbH (MVV), Mannheim (Germany))

    1994-03-01

    The ever-increasing competition on the heating market has forced us - within the framework of overall optimization of district-heating service - to continue improving our house substantions as the main link between distribution lines and consumer installations. The aim is to develop a modern, high-tech 'product', capable of supplying any demand regardless of the technical parameters involved. Furthermore, it should integrate the best of the respective economic, functional, operational, and aesthetic attributes of this technology. These objectives provide us with very precisely definable demands on the various elements of our hourse substantions. The following considerations form the main focus of optimization: Compactness, the right concept to meet each individual case, coverage of a capacity range of up to 1 MW, managing the large variety of alternatives with the aid of a modular system, incorporating thermostats oriented to outside temperatures, resolving questions on integration of water-heating systems for domestic use into the substantion concepts, and designing system piping and instrumentation. However, investments as well as operating and maintenance costs should always be maintained well within the lowest possible parameters. This article presents the most important basic thinking on these points. It also provides information on some additional aims of optimization, references, and projects already completed. (orig.)

  9. Effect of heat stress on six beef breeds in the Zastron district: the ...

    African Journals Online (AJOL)

    LA Foster

    assumptions and philosophies without concrete evidence (Mentz, 2002). A contributing ... (Finch, 1986). The effects of heat on body temperature are determined not only by climate but also by the .... in selecting tropical beef cattle. However ...

  10. District heating in Lyons: self-monitoring and administrative control; Chauffage urbain de Lyon: autosurveillance et controle de l`Administration

    Energy Technology Data Exchange (ETDEWEB)

    Lartigue, D. [SLEC / PRODITH, 69 - Lyon (France)

    1996-12-31

    The district heat and cold system of Lyon city (France) is presented, with emphasis on the environmental performances of its boiler, burner and dust cleaning systems. Pollutant emissions are continuously monitored, controlled and regulated: the sensing and monitoring system is described together with the data acquisition and processing systems, allowing for a real time control of the plants and the whole heating system. Relations with the local administration and audits for ISO 14000 certification are also discussed

  11. Demonstration project in Volgograd on transfer of know-how from the district heating sector in Denmark to Russia. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    A demonstration project on district heating know-how has been financed by the Danish Technical Assistance Programme administrated by the Danish Energy Agency. A demonstration project in Volgograd was approved, with a budget of only 200.000 DKK (180.000 Rbl). The administration of the project, from fact finding to the final report, has been very efficient in particular to other technical assistance programmes. Although the total budget is low only around 15% of the manpower has been used on administration. The transfer of specific technical experience can be summarized in the following: Installation of small decentralized heat exchanger units for preparation of hot water; Construction of low-cost decentralized heat exchanger installations for preparation of hot water; Installation of thermostatic valves; Installation of small substations for heating and hot water; Use of drain pumps for draining under constructions of district heating pipes to prevent outside corrosion; Design principles for construction and rehabilitation of concrete duct systems with internal and outside draining; Design principles for preinsulated pipes; Principles for monitoring the quality of supply in a local district heating network at the lowest costs by monitoring the critical differential pressure. (EG)

  12. District heating and cooling systems for communities through power plant retrofit and distribution network. Volume 3. Tasks 4-6. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Watt, J.R.; Sommerfield, G.A.

    1979-08-01

    Stone and Webster Engineering Corporation is a member of the Demonstration Team to review and assess the technical aspects of cogeneration for district heating. Task 4 details the most practical retrofit schemes. Of the cogeneration schemes studied, a back-pressure turbine is considered the best source of steam for district heating. Battelle Columbus Laboratories is a member of the Demonstration Team employed to investigate several institutional issues affecting the success of district heating. The Toledo Edison legal staff reviewed the legal aspects of mandate to serve, easement and franchise requirements, and corporate charter requirements. The principal findings of both the Battelle investigations and the legal research are summarized in Task 5. A complete discussion of each issue is included in the two sections labeled Legal Issues and Institutional Issues. In Task 6, Battelle Columbus Laboratories completed a preliminary economic analysis, incorporating accurate input parameters applicable to utility ownership of the proposed district-heating system. The methodology used is summarized, the assumptions are listed, and the results are briefly reviewed.

  13. The Exergetic, Environmental and Economic Effect of the Hydrostatic Design Static Pressure Level on the Pipe Dimensions of Low-Energy District Heating Networks

    DEFF Research Database (Denmark)

    Tol, Hakan İbrahim; Svendsen, Svend

    2013-01-01

    Low-Energy District Heating (DH) systems, providing great energy savings by means of very low operating temperatures of 55 °C and 25 °C for supply and return respectively, were considered to be the 4th generation of the DH systems for a low-energy future. Low-temperature operation is considered t...

  14. Rentability of grids. Key to success of near-by district heating; Rentabilitaet der Netze. Schluessel zum Erfolg der Nah-/Fernwaerme. Moeglichkeiten moderner Feuchtewarnsysteme

    Energy Technology Data Exchange (ETDEWEB)

    Kamkalow, F.; Kuehn, H. [Brandes GmbH, Eutin (Germany)

    2008-06-15

    Millions of passenger cars are sold world-wide every year. All of them are equipped with safety systems. No user would dream of installing systems that would, for example, trigger an airbag long after the accident. Why, then, do users of district heating grids think differently? (orig.)

  15. Swedish Homeowners' Attitude towards Water-Based Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Gustavsson, L.; Mahapatra, K. (Mid Sweden Univ., Ecotechnology, SE-831 25 Oestersund (Sweden)). e-mail: leif.gustavsson@miun.se

    2008-10-15

    In 2004 and 2007, we conducted questionnaire surveys of 1,500 randomly selected Swedish homeowners of detached houses to understand their attitude towards adopting an innovative heating system (IHS). The results showed that there was no substantial change in homeowners' attitude towards IHSs. More than 80% of the respondents did not intend to install a new heating system. Economic aspects and functional reliability were the most important factors in the respondents' choice of heating system while environmental factors were of less importance. Installers were the most frequently consulted source of information on heating systems. Respondents perceived the relative advantage of pellet boilers over oil or electricity-based heating systems, but bedrock heat pump system was ranked higher than pellet heating system in every aspect except for investment cost. Pellet heating system has advantages with respect to investment cost. District heating system was considered as most functionally reliable and automatic. Keywords: Heat sector, socio-economic aspects, market implementation

  16. Exploration and drilling for geothermal heat in the Capital District, New York. Volume 4. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1983-08-01

    The Capital District area of New York was explored to determine the nature of a hydrothermal geothermal system. The chemistry of subsurface water and gas, the variation in gravity, magnetism, seismicity, and temperature gradients were determined. Water and gas analyses and temperature gradient measurements indicate the existence of a geothermal system located under an area from Ballston Spa, southward to Altamont, and eastward toward Albany. Gravimetric and magnetic surveys provided little useful data but microseismic activity in the Altamont area may be significant. Eight wells about 400 feet deep, one 600 feet and one 2232 feet were drilled and tested for geothermal potential. The highest temperature gradients, most unusual water chemistries, and greatest carbon dioxide exhalations were observed in the vicinity of the Saratoga and McGregor faults between Saratoga Springs and Schenectady, New York, suggesting some fault control over the geothermal system. Depths to the warm fluids within the system range from 500 meters (Ballston Spa) to 2 kilometers (Albany).

  17. Modeling and Exergy Analysis of District Cooling

    DEFF Research Database (Denmark)

    Nguyen, Chan

    . As a principle example, the CO2 emission for each of the cooling and heating consumer is found. The conclusion is analogue to the exergy costing method, i.e. the exergoenvironmmental method can be used as motivation for reducing CO2 emission. One of the main obstacles with district cooling in a traditional water......In this thesis energy, exergy and exergoeconomic analysis has been carried out on a different number of co-generation energy systems involving cooling. The models and methods developed can be used as a frame work to improve the district heating and cooling system thermodynamically and...... in a district heating system based on combined heat and power plants (CHP). A theoretical comparison of trigeneration (cooling, heating and electricity) systems, a traditional system and a recovery system is carried out. The comparison is based on the systems overall exergy efficiency. The traditional system...

  18. Multi-agent control for integrated heat and electricity management in residential districts

    NARCIS (Netherlands)

    Booij, P.S.; Kamphuis, V.; Pruissen, O.P. van; Warmer, C.

    2013-01-01

    For the built environment it is envisaged that in the next decades the total annual energy demand, both thermal and electric, could be covered by renewable sources generated within the built environment. More and more thermoelectric elements, such as heat pumps and thermal storage, will enable conve

  19. Comparison of Low-temperature District Heating Concepts in a Long-Term Energy System Perspective

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Østergaard, Dorte Skaarup; Yang, Xiaochen

    2017-01-01

    renewable energy systems. This study compares three alternative concepts for DH temperature level: Low temperature (55/25 °C), Ultra-low temperature with electric boosting (45/25 °C), and Ultra-low temperature with heat pump boosting (35/20 °C) taking into account the grid losses, production efficiencies...

  20. Multi-agent control for integrated heat and electricity management in residential districts

    NARCIS (Netherlands)

    Booij, P.S.; Kamphuis, V.; Pruissen, O.P. van; Warmer, C.

    2013-01-01

    For the built environment it is envisaged that in the next decades the total annual energy demand, both thermal and electric, could be covered by renewable sources generated within the built environment. More and more thermoelectric elements, such as heat pumps and thermal storage, will enable conve

  1. Achieving low return temperature for domestic hot water preparation by ultra-low-temperature district heating

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Svendsen, Svend

    2017-01-01

    to achieve high efficiency of the ULTDH system, the return temperature should be as low as possible. For the energy-efficient buildings in the future, it is feasible to use ULTDH to cover the space heating demand. However, considering the comfort and hygiene requirements of domestic hot water (DHW...

  2. Thermomechanical properties of polyurethane insulation used in district heating pipes; Termomekaniska egenskaper hos kulvertisolering av PUR-cellplast

    Energy Technology Data Exchange (ETDEWEB)

    Bergstroem, G.; Karlsson, Jonas [Swedish National Testing and Research Inst., Goeteborg (Sweden)

    1996-08-01

    The load bearing capacity of the types of rigid expanded polyurethane which is used as insulation in underground mains in district heating systems has been studied in this project over the temperature range 23 deg C to 170 deg C. The objective has been to acquire such knowledge concerning the thermal and mechanical properties of the materials that their load bearing capacity can be predicted for a service life of at least 30 years. Two reference materials and two commercial materials have been studied in addition to two materials produced in the laboratory. The investigations were mainly performed as creep tests at definite temperature levels, and extended over periods ranging from 1 hour to 2 years. An endeavour was then made to incorporate the results into a general thermomechanical model, with different parameters adapting the model to the different materials. The comprehensive description of time and temperature dependence is given in the form of master curves for the temperature 100 deg C and with conversion factors for other temperatures. The measurements have shown that PUR insulation has a more complicated time and temperature dependence than had been expected. This means that the descriptions of material behaviour presented must be seen as a first approximation that must be improved in order that an adequate margin of safety may be attained in the planned FEM calculations for underground heating mains subjected to long term loading. 15 refs, 34 figs

  3. Integrated assessment of supply and efficiency resources for the district heating system, City of Handlova, Republic of Slovakia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This city needs to replace its old district heating system which is unreliable and expensive to maintain. Current plant is owned by a state-run utility; the plant is scheduled for privatization, and the city is examining options for its upgrade. Analysis and preparation for this activity is documented in demand-side and supply-side technical and economic analyses and in this integrated demand/supply report. Preliminary projections indicate the cost of heating from a cost per unit of energy basis and from the perspective of an apartment dweller in Handlova on a total cost per year basis. The centralized coal cogeneration option is the least expensive on a levelized energy cost both with and without energy efficiency. Centralized coal/gas dual-fuel cogeneration is a close second, and the decentralized gas natural gas boilers is significantly more expensive. When the effect of building efficiency measures is evaluated, efficiency always increases the cost on a levelized energy cost basis, but on a levelized cost per flat basis, both centralized systems with buildings efficiency are less expensive than without.

  4. Situation analysis in relation to district heating and CHP in the Baltic Sea Region: Estonia, Latvia, Lithuania, Poland, Russia, Kaliningrad

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-11-01

    such bodies must be to secure the implementation of national energy policy, and of the acquis communautaire in the countries where this is relevant. Laying out the role gas, district heating and CHP respectively should be a main priority. Institute a continuous dialogue between key political and market actors, to optimise the relation between natural gas, district heating, and condensing power. Its aim should also be to institute measures that will boost investments. (EHS)

  5. The development of a new district heating concept: Network design and optimization for integrating energy conservation and renewable energy use in energy sustainable communities

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Rosa, A.

    2012-07-01

    PART I of this doctoral thesis consists of 6 chapters. Chapter 1 summarizes the main issues caused by the use of energy resources. They involve ecological, economic, demographical and socio-political topics that are linked together and define the background of the thesis. Chapter 2 describes the state-of-the-art of District Heating (DH) systems, with focus on the present and future situation in Denmark. The core of the thesis consists of the development of a new DH paradigm, the ''Low- Temperature District Heating (LTDH)'', the study of its potential, and investigations of technical options which improve its applicability in terms of energy performance and socio-economy. Chapter 3 describes the whole idea about LTDH. Chapter 4 presents the hypotheses of the studies, draws the boundaries between the focus area of the thesis and other relevant aspects of the subject, describes the limitations of the work and lists the methods which were used. Chapter 5 explains the results of the scientific content reported in the articles in PART II. Article I introduces the technical and organizational strategies that can facilitate the establishment of a successful energy planning in a community. It analyses the state-of-the-art in community energy planning, discusses critical issues, and points at the role of DH in moving towards sustainable heat supply. The articles II and III aim at providing science-based knowledge for the development of improved solutions for the DH networks; they focus on the performance simulation of DH pipelines through models for assessing the energy performance of innovative pipe geometries, materials or system configurations. The models were validated against experimental measurements on real DH pipes. Article II considers the detailed steady-state modelling and analysis of heat losses in pre-insulated DH pipes. Article III focuses on the modelling and computation of the transient heat transfer in service pipes, which are important

  6. The Relationship Between Urban Reconstruction and Urban Heat Island Effect Based on Remote Sensing Technology: Cangxia District of Fuzhou City, China%旧城改造与城市热岛效应关系的遥感研究——以福州市苍霞片区为例

    Institute of Scientific and Technical Information of China (English)

    唐菲; 徐涵秋

    2011-01-01

    With the urban development, replanning and reconstruction of the old urban area have become key issues of the urban development. Over the past decade, Fuzhou City of Fujian Province, Southeast China, has paced up its reconstruction progress. The Cangxia District, located in the southwestern Fuzhou, was therefore replaned and reconstructed to improve people' s living conditions because the area was full of intensively-built shanties. In order to study the thermal environmental changes of the Cangxia District before and after the recon- struction, three Landsat TM images real-related information of the area, of 1986, 1996 and 2006 were utilized to such as land surface temperature (LST), perform feature extraction of ther- impervious surface area and vege- tation coverage. The quantitative analysis on the relationship between impervious surface and LST is a positive exponential relationship between the two factors. With the assistance of the Urban-Heat-lsland Ratio Index (URI), digital image processing on the three multi-temporal images has revealed the spatial and temporal variations of the urban heat island effect (UHIE) in the study area from 1986 to 2006. The results show that after the launch of the reconstruction project for the shanty-dominated area, the UHIE in the area has been greatly mitigated. In the past 20 years, the URI has been decreased from 0.648 in 1986 to 0.245 in 2006 owing to the significant decrease in high-density impervious surface areas and notably increase in vegetation covers. Obviously, the reconstruction is beneficial to the UHI mitigation of the Cangxia District.%随着城市建设的快速发展,老城区改造已成为城市发展的重点工程之一。福州市近十几年来对原有旧城区中的棚屋区进行了大规模的改造,改善原有的居住条件。利用遥感技术重点研究和评价了福州市苍霞片区棚屋区改造前后的热环境变化,利用系列LandsatTM影像反演了该区1986

  7. New CO{sub 2} neutral city area with integrated district heating system of the future in Hoeje Taastrup - Phase 1: Preparation of demonstration. Final report; Denmark; Ny CO{sub 2}-neutral bydel med fremtidens integrerede fjernvarmesystem i Hoeje Taastrup - Fase 1: Forberedelse af demonstration. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Kaarup Olsen, P.; Hummelshoej, R.M. (Cowi A/S (Denmark))

    2011-02-15

    The project has contributed considerably to developing and maturing many climate initiatives in Hoeje Taastrup municipality - including particularly having made an effort to develop and develop the plans for a CO{sub 2}-neutral quarter called 'Vision Gammelsa'. In this context, the project has involved relevant actors in the development of an energy concept for the quarter. The concept was later used as basis for an EU application to the CONCERTO programme, for which Hoeje Taastrup achieved final grant agreement in December 2009. In this way, the municipality obtained funding for a 6-year project 'ECO-Life' which will focus on energy measures in Hedehusene, Floeng and the Gammelsoe region. The project will be carried out in cooperation with a municipality in Lithuania (Birstonas) and Belgium (Kortrijk). In addition, the project supported the development of a climate plan and policy in the municipality. During the life of the project, the council has carried out a wide range of ambitious initiatives which to a great extent stems from the project and in particularly the cooperation that the project has brought along. Based on a preliminary draft proposal for the district, a number of energy concepts have been assessed that can make the district CO{sub 2}-neutral. Primary focus has been on the heat supply. It is recommended to establish a low-temperature heating network, since such a solution provides the best possibility of using surplus heat and renewable energy sources, and in the future, perhaps already in 15 years, district heating from VEKS will be CO{sub 2}-neutral. Three energy efficient and CO{sub 2} efficient district heating solutions have been investigated in more detail: 1) Local low-temperature district heating network with ground heat and solar heat. 2) Low-temperature district heating network based on return heat from the HTF/VEKS system. 3) Low-temperature district heating network with heat driven heat pumps and solar heat. All

  8. New CO{sub 2} neutral city area with integrated district heating system of the future in Hoeje Taastrup - Phase 1: Preparation of demonstration. Final report; Denmark; Ny CO{sub 2}-neutral bydel med fremtidens integrerede fjernvarmesystem i Hoeje Taastrup - Fase 1: Forberedelse af demonstration. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Kaarup Olsen, P.; Hummelshoej, R.M. (Cowi A/S (Denmark))

    2011-02-15

    The project has contributed considerably to developing and maturing many climate initiatives in Hoeje Taastrup municipality - including particularly having made an effort to develop and develop the plans for a CO{sub 2}-neutral quarter called 'Vision Gammelsa'. In this context, the project has involved relevant actors in the development of an energy concept for the quarter. The concept was later used as basis for an EU application to the CONCERTO programme, for which Hoeje Taastrup achieved final grant agreement in December 2009. In this way, the municipality obtained funding for a 6-year project 'ECO-Life' which will focus on energy measures in Hedehusene, Floeng and the Gammelsoe region. The project will be carried out in cooperation with a municipality in Lithuania (Birstonas) and Belgium (Kortrijk). In addition, the project supported the development of a climate plan and policy in the municipality. During the life of the project, the council has carried out a wide range of ambitious initiatives which to a great extent stems from the project and in particularly the cooperation that the project has brought along. Based on a preliminary draft proposal for the district, a number of energy concepts have been assessed that can make the district CO{sub 2}-neutral. Primary focus has been on the heat supply. It is recommended to establish a low-temperature heating network, since such a solution provides the best possibility of using surplus heat and renewable energy sources, and in the future, perhaps already in 15 years, district heating from VEKS will be CO{sub 2}-neutral. Three energy efficient and CO{sub 2} efficient district heating solutions have been investigated in more detail: 1) Local low-temperature district heating network with ground heat and solar heat. 2) Low-temperature district heating network based on return heat from the HTF/VEKS system. 3) Low-temperature district heating network with heat driven heat pumps and solar heat. All

  9. An Economic and Policy Analysis of a District Heating System Using Corn Straw Densified Fuel: A Case Study in Nong’an County in Jilin Province, China

    Directory of Open Access Journals (Sweden)

    Shizhong Song

    2016-12-01

    Full Text Available The development of district heating systems of corn straw densified fuel (CSDF-DHS is an important option to promote the use of bioenergy on a large scale for sustainable development, especially in China. At present, China’s biomass densified solid fuel (BSDF development lags behind previously planned target, main barriers of which are economic and policy support problems. Accurate case studies are key to analyze these problems. This manuscript takes Nong’an County in Jilin Province of China as an example to establish a techno-economic model to evaluate the economic performance of a CSDF-DHS under two policy scenarios. It calculates the economic performance under a benchmark market scenario (BMS and the current policy scenario (CPS and analyzes the influence of various policy instruments, including subsidies, carbon trading, and preferential taxation. The results indicate that: (1 The CSDF-DHS option is not competitive under the BMS or CPS compared to the traditional energy system based mainly on coal and liquefied petroleum gas; (2 Comparatively, the economic performance of corn straw briquette fuel (CSBF is better than that of corn straw pellet fuel (CSPF; and (3 further policy support can make CSDF-DHSs competitive in the market, especially with subsidies for concentrated heating services and CSDF, carbon trading, and economic compensation to reduce the profit margin of enterprises, which can make both CSPF-DHSs and CSBF-DHSs competitive. The research results could provide scientific basis for relevant policy making and project decision.

  10. Evaluation of European District Heating Systems for Application to Army Installations in the United States

    Science.gov (United States)

    2006-07-01

    less expensive, more efficient piping material, which reduces heat losses to ground, and is a safer medium with less potential to flash to steam at...to flash to steam at a leak. d. Allows use of less expensive, more efficient piping material. The lower temperature allows the use of polyurethane...Station 3 is to be built through the transformer station Nord . (This is separate from the central production plant HKW Magirusstraße.) Therefore

  11. Increasing utilisation of district heating through absorption cooling technology; Oekat fjaerrvaermeutnyttjande med hjaelp av absorptionstekniken

    Energy Technology Data Exchange (ETDEWEB)

    Bjurstroem, Henrik; Ingvarsson, Paul; Zinko, Heimo

    2010-10-15

    The purpose of the research project presented in this report was to find ways to return a lower temperature from the generator of the chillers in a supply/return connection. The initial target is 40 deg C. Ideally, the absorption chiller and possible ulterior uses of the remaining heat in the heat carrier (the water flowing through the generator) should be as close as possible to a pure heat load. The hot-water driven absorption chillers used today to produce cooling in DH networks are exclusively so-called single-effect (Sweden) chillers with water and lithium bromide as working pair. This study aims at raising as much as possible the upper bounds on the absorption chiller capacity that may be connected to a DH network, by lowering the temperature at the outlet. To this end, several approaches have been used: - A search for alternative designs of the absorption chiller, focusing on commercially available and tested technology, both those yielding a large temperature decrease over the generator and those that may be operated at lower temperatures than the conventional solutions; - An examination of the impact of further uses of the remaining heat on temperature in the return line. larger. Smaller units are considered only if they can be used to illustrate a principle. As a complement to this investigation, a few other issues have been treated: - What temperature levels should a system actually be designed for? - The LAVA method to calculate the impact of supply and return temperatures in the DH network on the economics of power production is presented; - Interesting technical solutions using desiccant-aided evaporative cooling are shortly described; - The modern developments in the field of working pairs (refrigerant and absorbent) are reviewed. Assumptions made here are that there is a significant demand for cooling, and that the demand is large enough to justify operating the cogeneration plant at a load level exceeding its lowest acceptable part load rather than

  12. Improving the Dimensioning of Piping Networks and Network Layouts in Low-Energy District Heating Systems Connected to Low-Energy Buildings: A Case Study in Roskilde, Denmark

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2011-01-01

    The paper presents a method for the design of a low-energy district heating (DH) system, concerning the studies of different pipe-dimensioning methods, substation types and network layouts. Computations were carried out separately on each of the pipe segments of which the DH network consisted...... dimensions were investigated for substations of different types containing buffer tanks and heat exchangers and for booster pumps installed at the DH network. Two types of network layouts were compared in terms of satisfaction of customers concerning the supply temperatures and heat loss within the DH...

  13. Cloud Coaching: Web-Based Learning Holds Promise, Especially for Districts with Limited Resources

    Science.gov (United States)

    Matsumura, Lindsay Clare; Bickel, Donna DiPrima; Zook-Howell, Dena; Correnti, Richard; Walsh, Marguerite

    2016-01-01

    Web-based coaching shows significant promise for linking teachers to highly expert practitioners. This is particularly important in districts that cannot afford to hire full-time school-based coaches or to train and support coaches to be experts in all content areas. While web-based teacher professional development shows a great deal of potential…

  14. Technical-Environmental-Economical Evaluation of the Implementation of a Highly Efficient District Heating System in China

    DEFF Research Database (Denmark)

    Zhang, Lipeng

    Over the past 30 years, China has experienced unprecedented urbanization, modernization, and economic development. In the last two decades, China has become one of the largest DH markets in the world, with a total DH production in 2013 amounting to 3,197,032 TJ. This number is still increasing...... and transfer state-of-the-art DH technologies to China and thus improve efficiency, economic operation, and environment protection in Chinese DH systems. There were three sub- hypotheses in this research. The first two sub-hypotheses focused on SH systems to improve the efficiency of Chinese DH systems...... is still billed as a fixed charge based on the floor heating area. This gives heat consumers no incentive to save heat and results in a lack of energy-saving consciousness. Consequently, consumers emit heat into the atmosphere by opening the window when indoor temperatures are higher than the comfort level...

  15. District heating operated adsorption heat pump with soil deposit for multistorey housing, office and institutional buildings - phase 1. Final report; Fjernvarmedrevne adsorptionsvarmepumper med jordlager til etageboliger, kontor- og institutionsbyggeri - fase 1. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    2009-08-15

    The main idea of the concept was to show new ways to improve the use of district heating used as driving energy in an adsorption heat pump. This can take free heat from borehole storage to heat the building. By this the borehole stor-age is cooled and can be used for cooling the following summer, either directly or by using the adsorption machine as a cooling machine. This will heat the borehole storage (regenerate it) and it is ready to use as heat pump the follow-ing winter. It was shown that with this concept, compared with the traditional solution, a reduction of CO{sub 2} emission of 29% ca be realised with a payback time of approx. 14 years. It was assumed that the concept could only be used under special circumstances (limestone in the grounds, large plants), but analysis has shown that modifications of the original concept makes it more generally applicable. It is assumed however that there is a cooling demand of at least half of the heat demand and it is assumed that low-temperature heating at max 35 degrees C and preferably lower can be used. The report contains a thorough analysis of the importance of various parameters for performance of systems using the concept. The market for adsorption machines has evolved during the project, such that on completion of the project better and cheaper machines are available. The concept is presently (August 2009) being implemented in two buildings, Green Light House and Viborg New City Hall. In Viborg City Hall a combination of heat and electrical heating / cooling is used, so that the heating (with heat pump) and cooling can be made with electricity or with district heating. This fits well into the future flexible energy with varying heat and electricity prices and availability. (author)

  16. District heating operated adsorption heat pump with soil deposit for multistorey housing, office and institutional buildings - phase 1. Final report; Fjernvarmedrevne adsorptionsvarmepumper med jordlager til etageboliger, kontor- og institutionsbyggeri - fase 1. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    2009-08-15

    The main idea of the concept was to show new ways to improve the use of district heating used as driving energy in an adsorption heat pump. This can take free heat from borehole storage to heat the building. By this the borehole stor-age is cooled and can be used for cooling the following summer, either directly or by using the adsorption machine as a cooling machine. This will heat the borehole storage (regenerate it) and it is ready to use as heat pump the follow-ing winter. It was shown that with this concept, compared with the traditional solution, a reduction of CO{sub 2} emission of 29% ca be realised with a payback time of approx. 14 years. It was assumed that the concept could only be used under special circumstances (limestone in the grounds, large plants), but analysis has shown that modifications of the original concept makes it more generally applicable. It is assumed however that there is a cooling demand of at least half of the heat demand and it is assumed that low-temperature heating at max 35 degrees C and preferably lower can be used. The report contains a thorough analysis of the importance of various parameters for performance of systems using the concept. The market for adsorption machines has evolved during the project, such that on completion of the project better and cheaper machines are available. The concept is presently (August 2009) being implemented in two buildings, Green Light House and Viborg New City Hall. In Viborg City Hall a combination of heat and electrical heating / cooling is used, so that the heating (with heat pump) and cooling can be made with electricity or with district heating. This fits well into the future flexible energy with varying heat and electricity prices and availability. (author)

  17. Inferring a district-based hierarchical structure of social contacts from census data.

    Directory of Open Access Journals (Sweden)

    Z Yu

    Full Text Available Researchers have recently paid attention to social contact patterns among individuals due to their useful applications in such areas as epidemic evaluation and control, public health decisions, chronic disease research and social network research. Although some studies have estimated social contact patterns from social networks and surveys, few have considered how to infer the hierarchical structure of social contacts directly from census data. In this paper, we focus on inferring an individual's social contact patterns from detailed census data, and generate various types of social contact patterns such as hierarchical-district-structure-based, cross-district and age-district-based patterns. We evaluate newly generated contact patterns derived from detailed 2011 Hong Kong census data by incorporating them into a model and simulation of the 2009 Hong Kong H1N1 epidemic. We then compare the newly generated social contact patterns with the mixing patterns that are often used in the literature, and draw the following conclusions. First, the generation of social contact patterns based on a hierarchical district structure allows for simulations at different district levels. Second, the newly generated social contact patterns reflect individuals social contacts. Third, the newly generated social contact patterns improve the accuracy of the SEIR-based epidemic model.

  18. Heat exchanger design based on economic optimisation

    Energy Technology Data Exchange (ETDEWEB)

    Caputo, Antonio C.; Pelagagge, Pacifico M.; Salini, Paolo [University of L' Aquila, Engineering Faculty, Monteluco di Roio 67100, L' Aquila (Italy)

    2008-07-15

    Owing to the wide utilization of heat exchangers in industrial processes, their cost minimization is an important target for both designers and users. Traditional design approaches are based on iterative procedures which gradually change design parameters until a satisfying solution, which meets the design specifications, is reached. However, such methods, besides being time consuming, do not guarantee the reach of an economically optimal solution. In this paper a procedure for optimal design of shell and tube heat exchangers is proposed, which utilizes a genetic algorithm to minimize the total cost of the equipment including capital investment and the sum of discounted annual energy expenditures related to pumping. In order to verify the capability of the proposed method, three case studies are also presented showing that significant cost reductions are feasible with respect to traditionally designed exchangers. In particular, in the examined cases a reduction of total costs up to more than 50% was observed. (author)

  19. Heat exchanger design based on economic optimization

    Energy Technology Data Exchange (ETDEWEB)

    Caputo, Antonio C.; Pelagagge, Marcello P.; Salini, Paolo [University of l' Aquila (Italy). Faculty of Engineering], e-mail: caputo@ing.inivaq.it, e-mail: pelmar@ing.inivaq.it, e-mail: salini@ing.inivaq.it

    2006-07-01

    Owing to the wide utilization of heat exchangers in industrial processes their cost minimization is an important target for both designers and users. Traditional design approaches are based on iterative procedures which assume a configuration and gradually change design parameters until a satisfying solution is reached which meets the design specifications. However, such methods, besides being time consuming, do not guarantee the reach of an optimal solution. In this paper a procedure for optimal design for shell and tube heat exchangers is proposed which utilizes a genetic algorithm to minimize the total discounted cost of the equipment including the capital investment and pumping related annual energy expenditures. In order to verify the performances of the proposed method four case studies are also presented showing that total cost reductions greater than 15% are feasible respect traditionally designed exchangers. (author)

  20. Direct use of geothermal energy, Elko, Nevada district heating. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lattin, M.W.; Hoppe, R.D.

    1983-06-01

    In early 1978 the US Department of Energy, under its Project Opportunity Notice program, granted financial assistance for a project to demonstrate the direct use application of geothermal energy in Elko, Nevada. The project is to provide geothermal energy to three different types of users: a commercial office building, a commercial laundry and a hotel/casino complex, all located in downtown Elko. The project included assessment of the geothermal resource potential, resource exploration drilling, production well drilling, installation of an energy distribution system, spent fluid disposal facility, and connection of the end users buildings. The project was completed in November 1982 and the three end users were brought online in December 1982. Elko Heat Company has been providing continuous service since this time.

  1. How to Develop Inquiring Minds: District Implements Inquiry-Based Science Instruction

    Science.gov (United States)

    Beerer, Karen M.; Bodzin, Alec M.

    2004-01-01

    A Pennsylvania district used study groups to help teachers districtwide change their science teaching to standards-based practice of inquiry. Standards-based inquiry instruction requires that teachers have a deeper content knowledge as well as understand the process of inquiry. Making those changes requires support and a collegial environment.

  2. Challenges and Opportunities of Implementing District-based Health Information System in Ethiopia

    DEFF Research Database (Denmark)

    Mengiste, Shegaw Anagaw

    2005-01-01

    This paper has analyzed the challenges of sustainability and scalability of HIS. The empirical analysis was conducted in a backward and disadvantaged region of Ethiopia. An ongoing process of HISP (Health Information System Program) was addressed and the main challenges in the implementation...... of sustainable and scalable district-based health information system in the context of Primary Health Care (PHC) sector in Ethiopia were identified. Human resource, infrastructure, and HIS related problems are the main challenges hindering the implementation of sustainable and scalable district-based health...... information systems in the region....

  3. Heat expanded starch-based compositions.

    Science.gov (United States)

    Glenn, Gregory M; Klamczynski, Artur K; Holtman, Kevin M; Shey, Justin; Chiou, Bor-Sen; Berrios, Jose; Wood, Delilah; Orts, William J; Imam, Syed H

    2007-05-16

    A heat expansion process similar to that used for expanded bead polystyrene was used to expand starch-based compositions. Foam beads made by solvent extraction had the appearance of polystyrene beads but did not expand when heated due to an open-cell structure. Nonporous beads, pellets, or particles were made by extrusion or by drying and milling cooked starch slurries. The samples expanded into a low-density foam by heating 190-210 degrees C for more than 20 s at ambient pressures. Formulations containing starch (50-85%), sorbitol (5-15%), glycerol (4-12%), ethylene vinyl alcohol (EVAL, 5-15%), and water (10-20%) were studied. The bulk density was negatively correlated to sorbitol, glycerol, and water content. Increasing the EVAL content increased the bulk density, especially at concentrations higher than 15%. Poly(vinyl alcohol) (PVAL) increased the bulk density more than EVAL. The bulk density was lowest in samples made of wheat and potato starch as compared to corn starch. The expansion temperature for the starch pellets decreased more than 20 degrees C as the moisture content was increased from 10 to 25%. The addition of EVAL in the formulations decreased the equilibrium moisture content of the foam and reduced the water absorption during a 1 h soaking period.

  4. Shelter planning based on self-saving concepts in urban residential districts

    Directory of Open Access Journals (Sweden)

    Buri Qi

    2017-01-01

    Full Text Available With increasing population density in Asia, the potential higher risk was resulted from the residential districts with the higher plot ratio, especially in some megapolis (eg. Beijing and Shanghai. Presently it is more difficult for the rescue operation during the disasters because of the decreasing safe space among the buildings as a result of higher buildings and denser the district. Thus, an immediate self-saving action is more important than before during the disaster in the residential districts, and its realization depends on the reasonable shelter planning and its management system. In this study, the factors related to the self-saving were analyzed and concluded by the related the literatures retrieval and case study, and the case study was done by the in-depth interview and questionnaires in three different residential districts in Shanghai. It was found that the following factors related to the self-saving should be considered in the shelters planning: the distribution of the shelters including their space accessibility and area, evacuation passageways, the facilities of the disaster prevention (such as fire hydrant and guide signs and subsidiary facilities (such as vegetation for the disaster prevention, the social cohesion, awareness of the self-saving and disaster prevention. Simultaneously, the shelters planning countermeasures based on the self-saving were proposed, which provided some theoretical bases for the study  and plan of the security residential districts in future.

  5. Solar district heating, an option for future power supply in urban areas; Solare Nahwaerme - eine Option fuer die zukuenftige Energieversorgung im Siedlungsbereich

    Energy Technology Data Exchange (ETDEWEB)

    Fisch, M.N. [Technische Univ. Braunschweig (Germany). Fachbereich fuer Architektur]|[Steinbeis-Transferzentrum Energie, Gebaeude- und Solartechnik, Stuttgart (Germany)

    1999-03-01

    Small-scale solar-assisted district heating was successfully demonstrated in Germany in the first half of this decade. Large-scale systems with long-term thermal storage went into operation in Hamburg and Friedrichshafen at the end of 1996, and the first system with ground probe thermal storage in Neckarsulm at the end of 1997; a fourth installation with pebble/water thermal storage will become operational in the second half of 1998 in Chemnitz. What appeared utopian for many years became thus reality - space heating in Winter with solar energy gathered in Summer. Large solar installations are at least twice as cost-effective as small systems inspite of cost reduction achieved. Large systems avoid about two to three times more CO{sub 2}-emissions than small systems, based on the same amount of monetary investment. The system in Friedrichshafen cost 1.100 DM per m{sup 2} of collector inclusive long-term heat storage (or 11.000 DM per apartment) and covers nearly 50% of annual space heating and warm water demand. The investment costs in Neckarsulm are already about 20% lower; the specific cost for heat ranges between 300 and 500 DM/MWh. (orig.) [German] Nach der erfolgreichen Erprobung von kleineren solarunterstuetzten Nahwaermeprojekten in der ersten Haelfte der neunziger Jahre in Deutschland gingen Ende 1996 in Hamburg und Friedrichshafen die ersten solaren Grossanlagen mit Langzeit-Waermespeicher und Ende 1997 in Neckarsulm die erste Anlage mit Erdsonden-Waermespeicher in Betrieb; eine vierte solarunterstuetzte Nahwaermeversorgung mit einem Kies/Wasser-Waermespeicher wurde in der zweiten Haelfte 1998 in Chemnitz fertig gestellt. Damit wurde erreicht, was ueber Jahre hinweg utopisch erschien - mit Sonnenenergie aus dem Sommer Gebaeude im Winter zu beheizen. Trotz Kostenreduktion bei kleinen Anlagen bleiben grosse Solaranlagen mindestens doppelt so wirtschaftlich. Bei gleicher Investitionssumme vermeiden Grossanlagen etwa zwei- bis dreimal mehr klimaschaedliche CO

  6. Transformation strategies of fossil central district heating supply to grids with an enhanced portion of renewable energies; Transformationsstrategien von fossiler zentraler Fernwaermeversorgung zu Netzen mit hoeheren Anteilen erneuerbarer Energien

    Energy Technology Data Exchange (ETDEWEB)

    Paar, Angelika; Herbert, Florian; Pehnt, Martin [ifeu-Institut fuer Energie- und Umweltforschung GmbH, Heidelberg (Germany); Ochse, Susanne; Richter, Stephan; Maier, Stefanie; Kley, Magalie [GEF Ingenieur AG, Leimen (Germany); Huther, Heiko; Kuehne, Jens; Weidlich, Ingo [AGFW - Der Energieeffizienzverband fuer Waerme, Kaelte und KWK e.V., Frankfurt am Main (Germany)

    2013-04-15

    A considerable portion of the primary energy consumption in Germany is used to provide process heat and space heating as well as for the hot water processing. The heat supply and the enhancement of the portion of renewable energy sources are particularly important for the reduction of greenhouse gas emissions. The contribution under consideration deals with the question of how the portion of renewable energy can be increased in existing district heating systems. The potential utilization of renewable energy sources in the district heating is analyzed systematically.

  7. Ball cocks for subsurface installation for utilization in district heating grids; Erdeinbau-Kugelhaehne fuer den Einsatz in Fernwaerme-Netzen

    Energy Technology Data Exchange (ETDEWEB)

    Burg, Albert

    2009-07-01

    As shut-off valves in buried pipelines, ball cocks are used almost exclusively. The rated caliber is between DN 20 and DN 1000. The problem in district heating grids consists in the fact that shut-off valves are operated only in case of emergencies or during grid extensions, but it is very important that they function reliably in these critical conditions even after a life of 30 years. Another problem in district heating grids is the fact that the flow direction can be reversed, depending on the mode of operation of the grid. Fittings therefore must provide tight sealing on both sides. The contribution lists potential causes of damage and proposes countermeasures and preventive measures. (orig.)

  8. Utilization of waste heat from Vienna waste incinerators for the operation of a district cooling grid. Effects on the primary energy efficiency of district heating and district cooling in Vienna; Nutzung der Abwaerme aus den Wiener Abfallverbrennungsanlagen fuer den Betrieb eines Fernkaeltenetzes. Auswirkungen auf die Primaerenergieeffizienz der Fernwaerme und Fernkaelte in Wien

    Energy Technology Data Exchange (ETDEWEB)

    Schindelar, F.; Wallisch, A. [Fernwaerme Wien GmbH, Vienna (Austria)

    2007-07-01

    The need of coldness increases and has to be covered efficiently as well as ecologically. At optimal constellation and mode of operation, the establishment of refrigeration plants from absorption refrigerators and compression refrigerators seems to be economically more competitive than decentralized plants. The optimal constellation is present, if: (a) ecologically and economically favourable waste heat are available; (b) Electricity from the domestic production with waste energy is present; (c) Resources-conserving recirculation cooling possibilities exist; (d) cooling water tanks and/or hot water tanks are available for top coverage; (e) a high grid density exists; (f) in-building station corresponds to the technical conditions. If these fundamental conditions are present, then the district coldness offers a good chance for waste incineration plants to use a safe heat consumer also in summer and to utilize optimally the existing energy.

  9. Prefabricated modular district heating station is available rapidly. Welded transfer station DSP Midi; Vorgefertigte, modulare Fernwaermestation ist schnell verfuegbar. Geschweisste Uebergabestation DSP Midi

    Energy Technology Data Exchange (ETDEWEB)

    Simon, Joern [Danfoss GmbH, Hamburg (Germany). District Energy Div.

    2012-03-15

    Danfoss GmbH (Hamburg, Federal Republic of Germany) has developed a modular, standardized approach for welded district heating stations. The prefabricated transfer stations with a capacity up to 250 kW can be supplied in a compact frame. These stations have short delivery times and are extremely flexible: DSP MIDI systems have a modular design and adapters. Thus, DSP MIDI systems cover about 90 % of the technical connection requirements in Germany.

  10. In-service leak testing of district heating systems using dissolved tracer gas. Final report; Betriebsbegleitende Lecksuche mit geloestem Tracergas in Fernwaermesystemen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Hergarten, A.; Althaus, W. [eds.

    1997-07-31

    The feasibility of in-service leak detection with dissolved tracer gas was investigated. Helium was selected as tracer gas because of its good diffusion characteristics, selective detectability at very low concentrations, inert and unproblematic behaviour within the district heating system, and good environmental compatibility. For a systematic investigation of the influencing parameters governing practical applications, a pipeline test field comprising about 240 m of KMR district heating pipelines and 61 controllable simulation leaks was constructed, and experiments using the new method were carried out. The required helium concentration amounts to a few grams of helium per cubic metre of district heating water. The water can be charged in the water preparation or feeding stage, and commercial detectors can be used. (orig./GL) [Deutsch] Zur Entwicklung einer betriebsbegleitenden Lecksuchmethode fuer erdverlegte Rohrleitungen wurden in einem Feasbility-Test die Machbarkeit der Tracergassuche mittels geloestem Spuergas bestaetigt. Als Tracergas wurde Helium aufgrund seines guenstigen Diffusionsverhaltens, seiner selektiven Nachweisbarkeit bei kleinsten Konzentrationen, seines inerten, unproblematischen Verhaltens im Fernwaermenetz und seiner guten Umweltvertraeglichkeit ausgewaehlt. Zur systematischen Untersuchung der Einflussparameter bei der Anwendung der Methode unter praxisnahen Bedingungen wurde ein Rohrleitungsversuchsfeld mit ca. 240 m KMR-Fernwaermeleitung und 61 regelbaren Simulationsleckagen aufgebaut und die neue Lecksuchmethode eingehend experimentell getestet. Die einzustellende Heliumkonzentration im Fernwaermewasser ist mit wenigen Gramm Helium je Kubikmeter Fernwaermewasser gering. Eine Vorrichtung fuer die empfohlene Beladung des gesamten Netzwasserinhalts kann in Wasseraufbereitung oder Nachspeisung des Netzes eingebunden werden. Zur Detektion koennen, marktverfuegbare Messgeraete verwendet werden. (orig./GL)

  11. 区域供能地下敷设输配管网传热分析方法%Heat transfer analysis of buried pipes in district heating and cooling system

    Institute of Scientific and Technical Information of China (English)

    衣健光

    2014-01-01

    地下敷设是区域供能输配管网的主要敷设方式,其传热计算用于确定保温层厚度、输配管网附加负荷、热损坏可能性。分析了影响地下敷设管网传热的因素,包括:流体与土壤之间的温差、管道的保温隔热性能、埋深、土壤导热系数以及相邻管道之间的间距。介绍了基于热阻的简化稳态计算方法,该方法极大地简化了计算工作量,且计算结果能够满足工程需要,同时该方法适用于大多数地下敷设管网的形式,可供工程设计人员参考。%Buried pipe network is the main way of distribution system in district heating and cooling systems,and its heat transfer calculation is used to determine the thickness of the insulation layer,accessory load of distribution system,and the possibility of thermal damage.Analyses the factors that influence the heat transfer calculation of buried pipe network,including temperature difference between fluid and soil, pipe insulation properties,depth,soil thermal conductivity and distance between adjacent pipes.Present the steady-state thermal calculation method based on thermal resistance formulations,which greatly simplifies the computational effort,and the calculated results can meet project needs.This method is suitable for the majority types of buried pipe network,so it can be used as reference for engineering design.

  12. Cogeneration heating system based on ejector heat pumps%基于喷射式热泵的热电联产供热系统

    Institute of Scientific and Technical Information of China (English)

    徐翔; 王远超; 张博

    2014-01-01

    There are two serious problems in the combined heat and power system:with the increase of heating area and quality, the heating is insufficient; the heavy discharge of low-grade thermal energy in the circulating cooling water wastes energy seriously. A novel system is presented based on ejector heat pumps (EDH-CHP) to solve the two problems by improving the heating capacity of the district heating system. It recycles the waste heat from circulating cooling water for district heating, and increases the heating capacity of the existing heating network by increasing the temperature difference between the water streams supplying and returning the original heating network. Compared with a traditional system, the new one has an additional ejector heat pump in the heating station, named HP1, and another ejector heat pump in the heating substation, named HP2. Thermodynamic analysis and experimental study are carried out for the two ejector heat pumps. The results show that both HP1 and HP2 can improve the performance of district heating under normal working conditions. Experimental results show that the COP of HP1 can reach 1.4-1.9 and the temperature of returning water in the original network can be decreased to 35℃ in HP2. A typical case study shows that the EDH-CHP system can improve the heating capacity of the existing heating network by 50% by adding 30% steam consumption, or improve the heating capacity of the existing heating network by 9% at the same steam consumption, or decrease the energy consumption by 6%at the same heating capacity.%热电联产面临着两个严重问题:供热面积与质量的增加导致供热不足;电厂凝汽器循环冷却水存在大量低品质热量浪费。为同时解决这两个问题,提出了一种利用喷射式热泵强化集中供热的新型EDH-CHP系统。该系统从循环冷却水中回收余热,并将余热应用于集中供热;另外通过增大供热一次网的供回水温差提高原一次网的供热

  13. Action Research as Empowering Professional Development: Examining a District-Based Teacher Research Course

    Science.gov (United States)

    Martell, Christopher C.

    2014-01-01

    Using critical constructivism as the theoretical lens, the researcher used action research to systematically examine the experience of PreK-12 teachers in his district-based teacher research professional development course, while also examining his development as a teacher educator. The results of this study showed that the teachers made progress…

  14. Computer-Based Acquisitions Procedures at Tarrant County Junior College District.

    Science.gov (United States)

    Corbin, John, Ed.

    1974-01-01

    The computer-based procedures described in this report form the basis of book acquisitions performed by the Automation and Technical Services Division in serving the Learning Resources Centers of the multi-campus Tarrant County Junior College District. The procedures, which are off-line in a batch mode, have been operational since 1968. Since 1970…

  15. A Management-Based CIPP Evaluation of a Northern New Jersey School District's Digital Backpack Program

    Science.gov (United States)

    Bachenheimer, Barry A.

    2011-01-01

    The purpose of this study was to evaluate the Digital Backpack program in a Northern New Jersey School District using the CIPP Management-Based Evaluation model as a framework. The Stufflebeam (1971) CIPP model is an acronym for Context, Input, Process, and Product Evaluation. A "Digital Backpack" is a rolling computer bag given to K-12…

  16. Central model predictive control of a group of domestic heat pumps, case study for a small district

    NARCIS (Netherlands)

    Leeuwen, van R.P.; Fink, J.; Smit, G.J.M.; Helfert, Markus; Krempels, Karl-Heinz; Donnellan, Brian; Klein, Cornel

    2015-01-01

    In this paper we investigate optimal control of a group of heat pumps. Each heat pump provides space heating and domestic hot water to a single household. Besides a heat pump, each house has a buffer for domestic hot water and a floor heating system for space heating. The paper describes models and

  17. Central model predictive control of a group of domestic heat pumps, case study for a small district

    NARCIS (Netherlands)

    van Leeuwen, Richard Pieter; Fink, J.; Smit, Gerardus Johannes Maria; Helfert, Markus; Krempels, Karl-Heinz; Donnellan, Brian; Klein, Cornel

    2015-01-01

    In this paper we investigate optimal control of a group of heat pumps. Each heat pump provides space heating and domestic hot water to a single household. Besides a heat pump, each house has a buffer for domestic hot water and a floor heating system for space heating. The paper describes models and

  18. Short-term forecasts of district heating load and outdoor temperature by use of on-line connected computers; Korttidsprognoser foer fjaerrvaermelast och utetemperatur med on-linekopplade datorer

    Energy Technology Data Exchange (ETDEWEB)

    Malmstroem, B.; Ernfors, P.; Nilsson, Daniel; Vallgren, H. [Chalmers Tekniska Hoegskola, Goeteborg (Sweden). Institutionen foer Energiteknik

    1996-10-01

    In this report the available methods for forecasting weather and district heating load have been studied. A forecast method based on neural networks has been tested against the more common statistical methods. The accuracy of the weather forecasts from the SMHI (Swedish Meteorological and Hydrological Institute) has been estimated. In connection with these tests, the possibilities of improving the forecasts by using on-line connected computers has been analysed. The most important results from the study are: Energy company staff generally look upon the forecasting of district heating load as a problem of such a magnitude that computer support is needed. At the companies where computer calculated forecasts are in use, their accuracy is regarded as quite satisfactory; The interest in computer produced load forecasts among energy company staff is increasing; At present, a sufficient number of commercial suppliers of weather forecasts as well as load forecasts is available to fulfill the needs of energy companies; Forecasts based on neural networks did not attain any precision improvement in comparison to more traditional statistical methods. There may though be other types of neural networks, not tested in this study, that are possibly capable of improving the forecast precision; Forecasts of outdoor temperature and district heating load can be significantly improved through the use of on-line-connected computers supplied with instantaneous measurements of temperature and load. This study shows that a general reduction of the load prediction errors by approximately 15% is attainable. For short time horizons (less than 5 hours), more extensive load prediction error reductions can be reached. For the 1-hour time horizon, the possible reduction amounts to up to 50%. 21 refs, 4 figs, 7 appendices

  19. Refurbishment and optimisation of the district heating system and the Morettina central heating station in Locarno, Switzerland; Sanierung und Optimierung des Waermeverbundes und der Heizzentrale Morettina in Locarno. Erfolgskontrolle der Betriebsoptimierung

    Energy Technology Data Exchange (ETDEWEB)

    Lanz, S. [Dr. Eicher und Pauli AG, Berne (Switzerland); Ceschi, P. A. [Calore SA, c/o S.E.S., Locarno (Switzerland)

    2004-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) discusses the successful operational optimisation of a district heating system in Locarno in southern Switzerland. The system supplies various public and private buildings with heat and cold. This pilot installation features boilers fired with liquefied gas, a combined heat and power unit and a combined heat-pump/refrigeration system. The refurbishment of the installations after three years of operation is described, which included changes to the system's hydraulics and control system as well as improvements to various sub-stations in the heating network. The results of the refurbishment, including better co-ordination of the various aggregates and lower operating temperatures, are discussed. Recommendations are also made on the planning, organisation and operation of future projects of this type.

  20. Heat pipes as perspective base elements of heat recovery in heat supply and ventilating systems

    Directory of Open Access Journals (Sweden)

    Matveev Andrey

    2017-01-01

    Full Text Available Thermotechnical characteristics of heat pipes are considered as high-efficient heat-transfer devices, which can provide energy-saving technologies for heat supply and ventilating systems and for different branches of industry. Thermotechnical and working (”performance capability” characteristics of heat pipes are investigated. By ”performance capability” of heat pipes and heat-transfer devices on heat pipes we mean the system state, where it can perform set functions and keep parameter values (thermal power, conductivity, thermal resistance, heat-transfer coefficient, temperature level and differential, etc. within the regulations of standardized specifications. The article presents theoretical and experimental methods of «gaslock» length determination on noncondensable gases during long-lasting tests of ammonia heat pipes made of aluminum shape АS – КRА 7.5 – R1 (alloy АD – 31. The paper gives results of research of thermotechnical characteristics of heat pipes in horizontal and vertical states (separate and as a set part while using different systems of thermal insulation. The obtained results of thermotechnical and resource tests show the advantages of ammonia heat pipes as basic elements for heat exchanger design in heating and ventilation systems.