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Sven Werner - One of the best experts on this subject based on the ideXlab platform.
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the status of 4th generation District Heating research and results
Energy, 2018Co-Authors: Henrik Lund, Svend Svendsen, Poul Alberg Østergaard, Sven Werner, Miguel Chang, Peter Sorknaes, Jan Eric Thorsen, Frede Hvelplund, Bent Ole Gram Mortensen, Brian Vad MathiesenAbstract:Abstract This review article presents a description of contemporary developments and findings related to the different elements needed in future 4th generation District Heating systems (4GDH). Unlike the first three generations of District Heating, the development of 4GDH involves meeting the challenge of more energy efficient buildings as well as the integration of District Heating into a future smart energy system based on renewable energy sources. Following a review of recent 4GDH research, the article quantifies the costs and benefits of 4GDH in future sustainable energy systems. Costs involve an upgrade of Heating systems and of the operation of the distribution grids, while benefits are lower grid losses, a better utilization of low-temperature heat sources and improved efficiency in the production compared to previous District Heating systems. It is quantified how benefits exceed costs by a safe margin with the benefits of systems integration being the most important.
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Large heat pumps in Swedish District Heating systems
Renewable & Sustainable Energy Reviews, 2017Co-Authors: Helge Averfalk, Urban Persson, Paul Ingvarsson, Mei Gong, Sven WernerAbstract:Power-to-heat solutions like heat pumps and electric boilers are foreseen to be possible future tools to stabilise international power markets with high proportions of variable power supply. Temporary low cost electricity can be used for heat generation at times with high availability of wind and solar power through substitution of ordinary heat supply, hence contributing to increased energy system sustainability. Power-to-heat installations in District Heating systems are competitive due to low specific investment and installation costs for large electric boilers, heat pumps, and heat storages. Several large-scale heat pumps were installed in Swedish District Heating systems during the 1980s, since a national electricity surplus from new nuclear power existed for some years. The aim of this paper is to summarise the accumulated operation experiences from these large Swedish heat pumps to support and facilitate planning of future power-to-heat solutions with heat pumps in District Heating systems. Gained experiences consider; installed capacities, capacity utilisation, heat sources used, refrigerant replacements, refrigerant leakages, and wear of mechanical components. The major conclusion is that many of the large thirty-year-old heat pumps are still in operation, but with reduced capacity utilisation due to internal competition from waste and biomass cogeneration plants in the District Heating systems.
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international review of District Heating and cooling
Energy, 2017Co-Authors: Sven WernerAbstract:Abstract The purpose with this review is to provide a presentation of the background for the current position for District Heating and cooling in the world, with some deeper insights into European conditions. The review structure considers the market, technical, supply, environmental, institutional, and future contexts. The main global conclusions are low utilisation of District Heating in buildings, varying implementation rates with respect to countries, moderate commitment to the fundamental idea of District Heating, low recognition of possible carbon dioxide emission reductions, and low awareness in general of the District Heating and cooling benefits. The cold deliveries from District cooling systems are much smaller than heat deliveries from District Heating systems. The European situation can be characterised by higher commitment to the fundamental idea of District Heating, lower specific carbon dioxide emissions, and higher awareness of the District Heating and cooling benefits. The conclusions obtained from the six contexts analysed show that District Heating and cooling systems have strong potentials to be viable heat and cold supply options in a future world. However, more efforts are required for identification, assessment, and implementation of these potentials in order to harvest the global benefits with District Heating and cooling.
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Cogeneration of biofuels and heat in the European District Heating systems
2017Co-Authors: Julia Hansson, Andrea Egeskog, Göran Berndes, Sven WernerAbstract:The European Union (EU) aims at an increased use of bioenergy in all sectors as well as an increased energy efficiency. The gasification of biomass with subsequent conversion to gaseous and liquid biofuels generates considerable amounts of surplus heat. Given that some of this heat is made useful in District Heating systems, the energy efficiency of such biofuel options would increase. Since the District Heating systems in the EU to a large extent is based on fossil fuels, CO2 emissions reduction from the District Heating systems could be an additional benefit. The aim of this study is to assess the potential for integrating biofuel plants generating surplus heat with the District Heating systems in the member states of the EU. On a national level, the heat sink represented by the District Heating systems is large enough to accommodate a substantial biofuel production. However, the realization of this potential is highly dependent on national conditions and its competitiveness against other heat sources in the District Heating systems. The attractiveness and possible impacts need to be further analyzed.
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risk of industrial heat recovery in District Heating systems
Energy Procedia, 2017Co-Authors: Kristina Lygnerud, Sven WernerAbstract:Abstract Industrial heat recovery can be used in District Heating systems. It is a possibility to make use of heat that is otherwise lost. Increased usage of industrial heat recovery reduces the need for fuel combustion lowering green-house gas (GHG) emissions, such as CO2. Industrial companies can, however, move or close down industrial activities. This is apprehended as a risk and lowers the interest of District Heating companies to invest in industrial heat recovery. In Swedish District Heating systems, industrial heat recoveries have been undertaken since 1974. Today, the heat recovery is active in about seventy systems. This leads to the question of how risky it is, for District Heating companies, to engage in industrial heat recovery. Over forty years of operation statistics have been collected and analyzed in order to estimate the risk of industrial heat recovery to District Heating companies. Key results show that the risk is not linked to different industrial branches. Recommendations include suggestions to management on how to consider risk and consequence when assessing potential industrial heat recovery investments.
Kristina Lygnerud - One of the best experts on this subject based on the ideXlab platform.
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Challenges for business change in District Heating
Energy Sustainability and Society, 2018Co-Authors: Kristina LygnerudAbstract:Background The Swedish District Heating sector is successfully transitioning to a low-carbon energy system. The industry has expanded since the 1950s and currently meets more than half the Swedish heat demand. The heat market was deregulated in 1996, and thereafter, companies have been exposed to an increasing number of challenges related to technology, institutional factors and market. Since municipal ownership dominates, municipal companies must manage these challenges to ensure future competitiveness. However, theory suggests that business change is difficult when the current model is still working. To date, Swedish District Heating companies have revisited their price models and customer perceptions. There is limited knowledge on how the business challenges are managed and on the management strategy’s impact on the business. In this paper, new knowledge is generated regarding how the customer and resource-oriented sides of the municipally owned District Heating business in Sweden are changing. Methods A case study approach was adopted. Data were collected by interviews and by review of the national research programme on District Heating (Fjärrsyn). The programme served as a proxy for frontline research on Swedish District Heating. The data were analyzed through the business model canvas framework. Results Changes to meet external pressures are identified on the customer side of the business model, but changes are also spreading to other parts of it. However, the key resource component (distribution networks and production unit) and its logic of economics of scale are unchanged and dominate. The logic is not compatible with shrinking heat demand; nevertheless, it is preferred. Conclusions It is concluded that external challenges have resulted in changes in the customer side of the business model. However, the largest challenge is the transformation of key resources. Accounting for external challenges extends the life of the current business model, but it is not increasing competitiveness. The prolonged life creates a window of opportunity for the companies to begin the needed transformation of their key resources. If the transformation is successful, District Heating will have a role in the future energy system. If the transformation is not undertaken, the future is less certain.
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risk of industrial heat recovery in District Heating systems
Energy Procedia, 2017Co-Authors: Kristina Lygnerud, Sven WernerAbstract:Abstract Industrial heat recovery can be used in District Heating systems. It is a possibility to make use of heat that is otherwise lost. Increased usage of industrial heat recovery reduces the need for fuel combustion lowering green-house gas (GHG) emissions, such as CO2. Industrial companies can, however, move or close down industrial activities. This is apprehended as a risk and lowers the interest of District Heating companies to invest in industrial heat recovery. In Swedish District Heating systems, industrial heat recoveries have been undertaken since 1974. Today, the heat recovery is active in about seventy systems. This leads to the question of how risky it is, for District Heating companies, to engage in industrial heat recovery. Over forty years of operation statistics have been collected and analyzed in order to estimate the risk of industrial heat recovery to District Heating companies. Key results show that the risk is not linked to different industrial branches. Recommendations include suggestions to management on how to consider risk and consequence when assessing potential industrial heat recovery investments.
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sparse District Heating in sweden
Applied Energy, 2008Co-Authors: Stefan Forsaeus Nilsson, Charlotte Reidhav, Kristina Lygnerud, Sven WernerAbstract:This paper presents a review of the sparse District-Heating research programme undertaken in Sweden between 2002 and 2006. The goal of the programme was to increase the future competitiveness for District heat in low heat density areas, e.g., suburban single-family houses and small villages. Such areas are unfavourable, since revenues from heat sold are low compared with the investment cost for the local distribution network. In Sweden, District heat has a dominant position in the heat market for residential and service-sector buildings. In order for the business to grow, it is necessary to increase the rate of expansion in the detached-house segment. This is why the programme was initiated. The extent of the programme was set at € 3.6 million with equal financing from the Swedish District-Heating Association and the Swedish Energy-Agency. The research was carried out in three phases: a state of the art survey; a development phase focused on productivity gains where new research on both technology and customer interaction was performed; and finally a demonstration phase where new methods were tested in full-scale field operation. The programme has shown that the Swedish District-Heating industry needs to adjust in order to reach a higher profitability for sparse District-Heating investments. Tradition from large-scale high-density District Heating is hard to scale to fit sparse District-Heating systems. For example, the construction becomes very labour intensive and the industry is weak when it comes to market-oriented business logic, sales and private customer interaction. Innovation seems to be a way forward and active management of innovations is a way to create increased value of the investments. Other keys to improving the profitability of sparse District-Heating investments are more efficient working routines (resulting in higher productivity) and revised ways of customer communications. These seem more important than increasing efficiency in District-Heating technology. © 2007.
Charlotte Reidhav - One of the best experts on this subject based on the ideXlab platform.
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Sparse District Heating and flexible District Heating pipes
2017Co-Authors: Charlotte ReidhavAbstract:The aim of this thesis is to describe sparse District Heating conditions and explore how to improve them. Few sparse areas are heated by District heat, which reflects the economic competitiveness. A method that could be used by the District Heating companies to identify the boundaries of profitable District heat is presented. Important key figures are identified when investigating the boundaries of competitive District heat. This method was identified using data gained from research on sparse areas in Goteborg, Sweden and demonstrates what to focus on in order to improve competitiveness. It is concluded that distribution heat losses must decrease in future connected sparse areas to be an efficient and competitive Heating alternative. The insulation properties of flexible District Heating pipes, widely used when connecting sparse areas, are an important issue when improving the energy efficiency. The long term insulation properties of flexible District Heating pipes are experimentally investigated by studying the cell gas transport in semi-flexible polyurethane foams. The results show that the insulation properties are impaired more rapidly than for traditional straight pipes. The flexibility of the material is partly achieved at the cost of faster gas transport. An effective diffusion barrier hindering this gas transport is thus important. A new method to determine the temperature-dependent thermal conductivity of flexible District Heating pipes is presented. The method is based on the fact that the temperature decline of hot water in a District Heating pipe placed in cool water depends on the thermal conductivity of the polyurethane foam. The temperature decline of the water inside the service pipe is measured and modelled numerically. The difference between measured and calculated temperatures is used to determine the temperature-dependent thermal conductivity and the specific heat by fitting. The method is based on simple measurements of the temperature decline of the service pipe water, and it is applied on single and twin pipes. A single experiment gives the thermal conductivity for a large temperature span.
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profitability of sparse District Heating
Applied Energy, 2008Co-Authors: Charlotte Reidhav, Sven WernerAbstract:The expansion of District Heating into areas of low heat densities (heat sparse areas) constitutes a challenge due to the higher distribution costs. The profitability of sparse District Heating has been analysed from actual investments in 74 areas with 3227 one-family houses connected to District Heating between 2000 and 2004 in Goteborg, Sweden. The profitability was estimated from a probable price model, a typical marginal heat generation cost, and the investments from the actual connections made. The analysis identified factors as the linear heat density and heat sold per house explaining the main variations in profitability. The profitability analysis was concluded with a competition analysis. The main conclusion is that sparse District Heating is possible when reaching low investment costs for the local distribution network and low marginal costs for the heat generation. In Sweden, the general competitiveness of sparse District Heating is facilitated by the high consumption taxes for fuel oil, natural gas, and electricity. Hence, it should be more difficult to introduce sparse District Heating in other countries with low energy taxes.
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sparse District Heating in sweden
Applied Energy, 2008Co-Authors: Stefan Forsaeus Nilsson, Charlotte Reidhav, Kristina Lygnerud, Sven WernerAbstract:This paper presents a review of the sparse District-Heating research programme undertaken in Sweden between 2002 and 2006. The goal of the programme was to increase the future competitiveness for District heat in low heat density areas, e.g., suburban single-family houses and small villages. Such areas are unfavourable, since revenues from heat sold are low compared with the investment cost for the local distribution network. In Sweden, District heat has a dominant position in the heat market for residential and service-sector buildings. In order for the business to grow, it is necessary to increase the rate of expansion in the detached-house segment. This is why the programme was initiated. The extent of the programme was set at € 3.6 million with equal financing from the Swedish District-Heating Association and the Swedish Energy-Agency. The research was carried out in three phases: a state of the art survey; a development phase focused on productivity gains where new research on both technology and customer interaction was performed; and finally a demonstration phase where new methods were tested in full-scale field operation. The programme has shown that the Swedish District-Heating industry needs to adjust in order to reach a higher profitability for sparse District-Heating investments. Tradition from large-scale high-density District Heating is hard to scale to fit sparse District-Heating systems. For example, the construction becomes very labour intensive and the industry is weak when it comes to market-oriented business logic, sales and private customer interaction. Innovation seems to be a way forward and active management of innovations is a way to create increased value of the investments. Other keys to improving the profitability of sparse District-Heating investments are more efficient working routines (resulting in higher productivity) and revised ways of customer communications. These seem more important than increasing efficiency in District-Heating technology. © 2007.
Daniel Trier - One of the best experts on this subject based on the ideXlab platform.
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towards solar District Heating with more than 70 solar fraction
Energy Procedia, 2015Co-Authors: Daniel TrierAbstract:Abstract In Denmark solar fractions up to about 50% are seen for large scale solar District Heating systems. The feasibility of higher solar fractions has been investigated in a case study. There is no direct subsidy for solar Heating in Denmark, but the taxes on the alternative (fuels) affects the feasibility of solar Heating for any District Heating plant. The results show that solar heat can be provided at competitive costs compared to what is seen at many Danish District Heating plants. The utility in the case study has not yet decided on a solar District Heating system size.
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Towards Solar District Heating with More than 70% Solar Fraction☆
Energy Procedia, 2015Co-Authors: Daniel TrierAbstract:Abstract In Denmark solar fractions up to about 50% are seen for large scale solar District Heating systems. The feasibility of higher solar fractions has been investigated in a case study. There is no direct subsidy for solar Heating in Denmark, but the taxes on the alternative (fuels) affects the feasibility of solar Heating for any District Heating plant. The results show that solar heat can be provided at competitive costs compared to what is seen at many Danish District Heating plants. The utility in the case study has not yet decided on a solar District Heating system size.
Stefan Forsaeus Nilsson - One of the best experts on this subject based on the ideXlab platform.
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sparse District Heating in sweden
Applied Energy, 2008Co-Authors: Stefan Forsaeus Nilsson, Charlotte Reidhav, Kristina Lygnerud, Sven WernerAbstract:This paper presents a review of the sparse District-Heating research programme undertaken in Sweden between 2002 and 2006. The goal of the programme was to increase the future competitiveness for District heat in low heat density areas, e.g., suburban single-family houses and small villages. Such areas are unfavourable, since revenues from heat sold are low compared with the investment cost for the local distribution network. In Sweden, District heat has a dominant position in the heat market for residential and service-sector buildings. In order for the business to grow, it is necessary to increase the rate of expansion in the detached-house segment. This is why the programme was initiated. The extent of the programme was set at € 3.6 million with equal financing from the Swedish District-Heating Association and the Swedish Energy-Agency. The research was carried out in three phases: a state of the art survey; a development phase focused on productivity gains where new research on both technology and customer interaction was performed; and finally a demonstration phase where new methods were tested in full-scale field operation. The programme has shown that the Swedish District-Heating industry needs to adjust in order to reach a higher profitability for sparse District-Heating investments. Tradition from large-scale high-density District Heating is hard to scale to fit sparse District-Heating systems. For example, the construction becomes very labour intensive and the industry is weak when it comes to market-oriented business logic, sales and private customer interaction. Innovation seems to be a way forward and active management of innovations is a way to create increased value of the investments. Other keys to improving the profitability of sparse District-Heating investments are more efficient working routines (resulting in higher productivity) and revised ways of customer communications. These seem more important than increasing efficiency in District-Heating technology. © 2007.