Combined heat and power (CHP) production in buildings is one of the mitigation options available for achieving a considerable decrease in GHG emissions. Micro-CHP (mCHP) fuel cells are capable of cogenerating electricity and heat very efficiently on a decentralised basis. Although they offer clear environmental benefits and have the potential to create a systemic change in energy provision, the diffusion of mCHP fuel cells is rather slow. There are numerous potential drivers for the successful diffusion of fuel cell cogeneration units, but key economic actors are often unaware of them. This paper presents the results of a comprehensive analysis of barriers, drivers and business opportunities surrounding micro-CHP fuel-cell units (up to 5 kWel) in the German building market. Business opportunities have been identified based not only on quantitative data for drivers and barriers, but also on discussions with relevant stakeholders such as housing associations, which are key institutional demand-side actors. These business opportunities include fuel cell contracting as well as the development of a large lighthouse project to demonstrate the climate-neutral, efficient use of fuel cells in the residential building sector. The next step could involve the examination and development of more detailed options and business models. The approach and methods used in the survey may be applied on a larger scale and in other sectors.
Many technical solutions have been developed to enhance the energy efficiency in buildings. However, the actual effectiveness and sustainability of these solutions often do not correspond to expectations because of the missing perspective of design, user's real needs, and unconsidered negative side effects of their use (rebounds). With the aim to help address these challenges, this paper presents results of a longitudinal living lab study and proposes a user-centered building management system (UC-BMS) as a prototype for office buildings. Based on mixed methods, UC-BMS was co-developed, tested, and evaluated in Germany in up to six office buildings, 85 offices, and within two heating periods. The results demonstrate that such user-oriented approach can save up to 20% of energy while maintaining or even improving comfort and work productivity. The findings show three main areas of intervention and elements of UC-BMS: (1) How interactive design and feedback systems (e.g., air quality) can stimulate ventilation practices and energy efficiency in offices and (2) supporting heating system optimization e.g., by better understanding office behavior. (3) Finally, an office comfort survey was conducted to enable communication between facility management and office users and thus limiting complaints and adapting the heating system towards actual office user needs.