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The Greenhouse Gas Protocol ‘Corporate Accounting and Reporting Standard’ (Corporate Standard) and the EU frameworks of guarantees of origin (GO) and emissions disclosure of energy carriers are intended to inform decision-making and reduce GHG emissions. This study analyses how decisions on purchases of electricity and district heating and decisions on combined heat and power (CHP) production are incentivised by the Corporate Standard and EU frameworks. It also analyses how the EU frameworks relate to CO 2 emissions reductions through CHP production. Using a consequential CO 2 assessment method for comparison, the study shows that purchasing decisions supported by the Corporate Standard or the GO scheme can increase total CO 2 emissions. It also shows that the Corporate Standard and EU frameworks can counteract CHP production and its contribution to CO 2 emissions reduction. We recommend that consequential GHG assessment methods be used for emissions reduction decisions, including when designing policy instruments aimed at emissions reduction. [ABSTRACT FROM AUTHOR]

A majority of previous studies on environmental problems caused by waste generation have focused on waste disposal issues without fully highlighting the primary reasons behind the problems. As a consequence, efforts to reduce these problems are usually directed towards the stakeholders that provide waste treatment and disposal instead of the stakeholders that contribute to waste generation. In order to detect connections between different problems of sustainability and to suggest measures which may contribute to their solutions, this study provides a simplified overview of the mechanisms behind waste generation and management. The results from the study show that the only way to eliminate problems of sustainability is to apply an upstream approach by dealing with the primary problems which occur in the early stages of the system (e.g. overconsumption of products, as well as use of finite resources, toxic materials, and non-recyclable materials). By dealing with these problems, the emergence of secondary problems would be prevented. Thereby, stakeholders who have the highest possibility to contribute to the sustainable development of the waste generation and management are the stakeholders from the origin of the product's life cycles, such as product developers, manufacturing companies, product users and policy makers. Different trade-off situations such as contradictions between economics, recyclability, energy efficiency, make it even harder to deal with issues of sustainability related to the system and to detect the stakeholders who may contribute to the development. One of the main conclusions from this study is that when transforming society towards a circular economy, the traditional view of separate systems for production and waste management must be changed. In order to refer to all problems of sustainability and also cover the top steps of the waste hierarchy, life cycle assessment of waste management should include manufacture and use of products ending up as waste. Waste entering the waste management system with “zero burden”, by releasing the previous actors of the waste life cycle from any responsibility related to the environment (i.e. by shifting the total environmental burden into the waste management system), does not capture the problems with waste generation. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the possibilities of converting industrial processes from electricity and fossil fuels to district heating in 83 companies in three Swedish counties. Effects on the local district heating systems were explored, as well as economic effects and impacts on global emissions of greenhouse gases. The study was conducted considering two different energy market conditions for the year 2030. The results show that there is a potential for increasing industrial district heating use in all analysed counties. The greatest potential regarding percentage is found in Jönköping, where the annual district heating use in the manufacturing companies could increase from 5 GW h to 45 GW h. The annual industrial district heating use could increase from 84 GW h to 168 GW h in Östergötland and from 14 GW h to 58 GW h in Västra Götaland. The conversion of the industrial production processes to district heating would lead to district heating demand curves which are less dependent on outdoor temperature. As a result, the utilization period of the base load plants (above all of the combined heat and power plants) would be prolonged; this would decrease district heating production costs due to the increased income from the electricity production. The energy costs for the industrial companies decrease after the conversions as well. Furthermore, the increased electricity production in the combined heat and power plants, and the decreased electricity and fossil fuel use in the industrial sector opens up a possibility for a reduction of global greenhouse gas emissions. The potential for the reduction of global greenhouse gas emissions is highly dependent on the alternative use of biomass and on the type of the marginal electricity producers. When the marginal effects from biomass use are not considered, the greenhouse gas emissions reduction is between 10 thousand tonnes of CO 2eq and 58 thousand tonnes of CO 2eq per year, depending on the county and the type of marginal electricity production plants. The highest reduction is achieved in Östergötland. However, considering that biomass is a limited resource, the increase of biomass use in the district heating systems may lead to a decrease of biomass use in other energy systems. If this assumption is included in the calculations, the conversion of the industrial processes to district heating still signify a potential for reduction of greenhouse gas emissions, but this potential is considerable lower. [ABSTRACT FROM AUTHOR]

Abstract: Biofuel production through polygeneration with heat as one of the by-products implies a possibility for cooperation between transport and district heating sectors by introducing large-scale biofuel production into district heating systems. The cooperation may have effects on both the biofuel production costs and the district heating production costs. This paper is the second part of the study that investigates those effects. The biofuel production costs evaluation, considering heat and electricity as by-products, was performed in the first part of the study. In this second part of the study, an evaluation of how such cooperation would influence the district heating production costs using Stockholm's district heating system as a case study was performed. The plants introduced in the district heating system were chosen depending on the future development of the transport sector. In order to perform sensitivity analyses of different energy market conditions, two energy market scenarios were applied. Despite the higher revenues from the sale of by-products, due to the capital intense investments required, the introduction of large-scale biofuel production into the district heating system does not guarantee economic benefits. Profitability is highly dependent on the types of biofuel production plants and energy market scenarios. The results show that large-scale biogas and ethanol production may lead to a significant reduction in the district heating production costs in both energy market scenarios, especially if support for transportation fuel produced from renewable energy sources is included. If the total biomass capacity of the biofuel production plants introduced into the district heating system is 900 MW, the district heating production costs would be negative and the whole public transport sector and more than 50% of the private cars in the region could be run on the ethanol and biogas produced. The profitability is shown to be lower if the raw biogas that is by-produced in the biofuel production plants is used for combined and power production instead of being sold as transportation fuel; however, this strategy may still result in profitability if the support for transportation fuel produced from renewable energy sources is included. Investments in Fischer–Tropsch diesel and dimethyl ether production are competitive to the investments in combined and power production only if high support for transportation fuel produced from renewable energy sources is included. [Copyright &y& Elsevier]

Abstract: This paper evaluates the effects on profitability of biofuel production if biofuel producers would sell the waste heat from the production to a local district heating system. All analyses have been performed considering four different technology cases for biofuel production. Two technology cases include ethanol production which is followed by by-production of raw biogas. This biogas can be upgraded and sold as biofuel (the first technology case) or directly used for combined heat and power production (the second technology case). The third and the fourth technology cases are Fischer-Tropsch diesel and dimethyl ether production plants based on biomass gasification. Two different district heating price levels and two different future energy market scenarios were considered. The sensitivity analyses of the discount rate were performed as well. In the case of energy market conditions, the profitability depends above all on the price ratio between biomass (used as the feedstock for biofuel production) and crude oil (used as the feedstock for fossil diesel and gasoline production). The reason for this is that the gate biofuel prices (the prices on which the biofuel would be sold) were calculated assuming that the final prices at the filling stations are the same as the prices of the replaced fossil fuel. The price ratios between biomass and district heating, and between biomass and electricity, also have an influence on the profitability, since higher district heating and electricity prices lead to higher revenues from the heat/electricity by-produced. Due to high biofuel (ethanol + biogas) efficiency, the ethanol production plant which produces upgraded biogas has the lowest biofuel production costs. Those costs would be lower than the biofuel gate prices even if the support for transportation fuel produced from renewable energy sources were not included. If the raw biogas that is by-produced would instead be used directly for combined heat and power production, the revenues from the electricity and heat would increase, but at the same time the biofuel efficiency would be lower, which would lead to higher production costs. On the other hand, due to the fact that it has the highest heat efficiency compared to the other technologies, the ethanol production in this plant shows a high sensitivity to the district heating price level, and the economic benefit from introducing such a plant into a district heating system is most obvious. Assuming a low discount rate (6%), the introduction of such a plant into a district heating system would lead to between 28% and 52% (depending on the district heating price level and energy market scenario) lower biofuel production costs. Due to the lower revenues from the heat and electricity co-produced, and higher capital investments compared to the ethanol production plants, Fischer-Tropsch diesel and dimethyl ether productions are shown to be profitable only if high support for transportation fuel produced from renewable energy sources is included. The results also show that an increase of the discount rate from 6% to 10% does not have a significant influence on the biofuel production costs. Depending on the biofuel production plant, and on the energy market and district heating conditions, when the discount rate increases from 6% to 10%, the biofuel production costs increase within a range from 2.2% to 6.8%. [Copyright &y& Elsevier]

Abstract: In this study, cooperation between Stockholm's transport and district heating sectors is analysed. The cooperation concerns the integration of biofuel polygeneration production. A MODEST optimisation model framework is used, assuming various energy market and transport sector scenarios for the year 2030. The scenarios with biofuel production and increased biofuel use in the region are compared with reference scenarios where all new plants introduced into the district heating sector are combined heat and power plants, and the share of biofuel used in the transport sector is the same as today. The results show that the cooperation implies an opportunity to reduce fossil fuel consumption in the sectors by between 20% and 65%, depending on energy market conditions and assumed transport sector scenarios. If we consider biomass an unlimited resource, the potential for greenhouse gas emissions reduction is significant. However, considering that biomass is a limited resource, the increase of biomass use in the district heating system may lead to a decrease of biomass use in other energy systems. The potential for reduction of global greenhouse gas emissions is thus highly dependent on the alternative use of biomass. If this alternative is used for co-firing in coal condensing power plants, biomass use in combined heat and power plants would be more desirable than biofuel production through polygeneration. On the other hand, if this alternative is used for traditional biofuel production (without co-production of heat and electricity), the benefits of biofuel production through polygeneration from a greenhouse gas emissions perspective is superior. However, if carbon capture and storage technology is applied on the biofuel polygeneration plants, the introduction of large-scale biofuel production into the district heating system would result in a reduction of global greenhouse gas emissions independent of the assumed alternative use of biomass. [Copyright &y& Elsevier]

Abstract: Ethanol can be produced with little impact on the environment through the use of polygeneration technology. This paper evaluates the potential of integrating a lignocellulosic ethanol plant into a district heating system by case study; the plant has an ethanol capacity of 95MW with biogas, electricity and heat as by-products. Stockholm’s district heating system is used as the case study, but the results may be relevant also for other urban areas. The system has been studied using MODEST – an optimisation model framework. The results show that introducing the plant would lead to a significant reduction in the cost of heat production. The income from the biofuels and electricity produced would be about €76million and €130million annually, respectively, which is an increase of 70% compared to the income from the electricity produced in the system today. Assuming that the electricity produced will replace marginal electricity on the European electricity market and that the biofuel produced will replace gasoline in the transport sector, the introduction of the polygeneration plant in the district heating system would lead to a reduction of global CO2 emissions of about 0.7million tonnes annually. [Copyright &y& Elsevier]