| 1. |
- Ahlgren, Erik, 1962, et al.
(författare)
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Assessing long-term sustainability of district heating systems
- 2012
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Ingår i: Proceedings EcoBalance Yokohama Nov 20-23 2012.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Biomass has become the main fuel for district heating (DH) systems in Sweden, and the substitution of biomass for oil during the last decades has led to considerably reduced CO2 emissions within the DH systems. Today, biomass is used both in heat- only boilers and, increasingly, in combined heat-and-power plants. District heating contributes also to increased sustainability through the utilization of industrial waste heat, which substitutes for primary energy use.With increasing pressure on constrained biomass resources and due to the geographical distribution of waste-heat sources, the municipal DH systems need to look for new solutions in order to further reduce their dependency on primary energy sources and enhance their sustainability. An integration of local systems into a regional heat system would allow for utilization of an increasing amount of waste heat, to capture scale effects of biomass combined heat and power plants and also to compensate for load profile differences between the local systems. DH systems are in addition being increasingly integrated with the power system and also with biorefineries through the production of bio transport fuels. Thus, the role of DH systems is becoming increasingly complex. This calls for new tools and methods to assess the sustainability of various possible future options and developments.The aim of the study is to assess the long-term sustainability of different DH developments with a focus on possibilities for integration of local DH systems into a regional system. In order to assess the sustainability in a long-term perspective of future DH options, we combine methods such as energy systems modeling and life cycle assessment in a procedural framework called life cycle sustainability assessment. The energy systems model applied is an optimizing bottom-up model. The study concerns the Vastra Gotaland region of Sweden and our model represents all the municipal DH systems at a detailed level. This presentation will mainly focus on the methodological aspects of the work: on how the different methods can be integrated and applied in a sustainability assessment of future district heating.
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| 2. |
- Fakhri, Akram, 1976, et al.
(författare)
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LARGE-SCALE UTILISATION OF EXCESS HEAT - ASSESSMENT THROUGH REGIONAL MODELLING
- 2014
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Ingår i: The 14th International Symposium on District Heating and Cooling.
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Konferensbidrag (refereegranskat)abstract
- The use of excess heat (EH) in district heating (DH) may contribute to increased sustainability through reduced use of primary energy. In Sweden biomass has become an important DH fuel during the last decades. Currently, there is a strong focus not only on use of biomass in heat and power generation but also for the transport sector. Competition for biomass, as a limited source, is thus likely to lead to higher demand and increasing prices of biomass. This study addresses the long-term system effects and connecting costs of three DH systems though a transmission pipeline that enables an increased use of EH from a large chemical cluster. The assessment is carried out with the optimising energy systems model MARKAL_WS, in which DH systems in the Västra Götaland region of Sweden are represented individually. Options for the production of transport biofuel as one potential competitor for biomass use are also included. The results show that the investment in the pipeline is cost-efficient when our energy system optimization takes both the DH systems and the transport sector into account, resulting in reduced total system cost.
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| 3. |
- Fakhri, Akram, 1976, et al.
(författare)
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MODELING REGIONAL DISTRICT HEATING SYSTEMS – THE CASE OF SOUTH-WESTERN SWEDEN
- 2012
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Ingår i: DHC13, the 13th International Symposium on District Heating and Cooling. ; , s. 219-224
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Biomass has become the main fuel for district heating (DH) systems in Sweden and is used both in heat-only boilers and, increasingly, in combined heat and power (CHP) plants. DH contributes also to increased sustainability through the utilization of waste heat (WH) which substitutes for primary energy use. Both the geographical distribution of WH sources and the scale effects of bio CHP plants are driving forces for the merging of DH systems. In this study, we are assessing opportunities for connecting local DH systems by transmission pipelines in the Västra Götaland region of Sweden and the system effects and costs of such investments. The assessment is carried out assisted by the optimizing MARKAL_WS model, in which the municipal DH systems in the region are represented individually as well as their relative geographical distribution. The results indicate that linking of local DH systems into larger regional systems can assist economic and environmental sustainability since it enables utilization of, currently unexploited, industrial waste heat resources. However, the cost-effectiveness of pipeline investments is dependent on the size of the available WH capacity. Furthermore, increased use of WH leads to less electricity generation from CHP in the region.
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