Overview
Buildings are a major source of greenhouse gas emissions and cost-effectively reducing their energy use and associated emissions is particularly challenging for the existing building stock, mainly because of the existence of many architectural and technical hurdles. The transformation of existing buildings into low-emission and low-energy buildings is particularly challenging in cities, where many buildings continue to rely too much on heat supply by fossil fuels. However, at the same time, there are specific opportunities to develop and take advantage of district-level solutions at urban scale. In this context, the project aims to clarify the cost-effectiveness of various approaches combining both energy efficiency measures and renewable energy measures at the district level. At this level, finding the balance between renewable energy measures and energy efficiency measures for the existing building stock is a complex task and many research questions still need to be answered, including:
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What are the cost-effective combinations between renewable energy measures and energy efficiency measures to achieve far-reaching reductions in greenhouse gas emissions and primary energy use in urban districts?
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What are the cost-effective strategies to combine district-level heating or cooling based on available environmental heat, solar energy, waste heat or natural heat sinks, with energy efficiency measures applied to building envelopes?
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How do related strategies compare in terms of cost-effectiveness and impacts with strategies that combine a decentralized switching of energy carriers to renewable energy sources with energy efficiency measures applied to building envelopes?
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Under which circumstances is it more appropriate to use available renewable energy potentials in cities at a district level, under which circumstances are decentralized renewable energy solutions more advantageous, in combination with energy efficiency measures applied to building envelopes?
The project objectives were to:
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give an overview on various existing and emerging technology options and on how challenges occurring in an urban context can be overcome,
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develop a methodology to identify cost-effective strategies for renovating urban districts, supporting decision makers in the evaluation of the efficiency, impacts, cost-effectiveness and acceptance of various solutions,
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illustrate such strategies in selected case studies and gather best-practice examples, and
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give recommendations to policy makers and energy related companies on how they can influence the uptake of cost-effective combinations of energy efficiency measures and renewable energy measures in building renovation at district level.
The deliverables from this project are:
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a report on technology overview, identifying energy efficiency measures and renewable energy measures at district level in an urban context,
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a methodology report on cost-effective building renovation at district level,
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supporting tools for decision makers: identification and adaptation of tools to support the application of the methodology in generic and case-specific assessments,
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a report on case studies, showing cost-effective combinations of energy efficiency measures and renewable energy measures in building renovation at district level,
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a report on good practice examples, showing strategies on transforming existing urban districts into low-energy and low-emission districts,
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guidebooks containing guidelines for policy makers and energy-related companies on how to encourage the market uptake of cost-effective strategies combining energy efficiency measures and renewable energy measures and guidelines for building owners and investors about cost-effective renovation strategies, including district-based solutions, and
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recommendations for subsidy programmes and for encouraging market uptake through competitions.
Participants
Austria, Czech Republic, Denmark, Italy, Portugal, Spain, Sweden, Switzerland