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Micro-cogeneration (micro-CHP) is an emerging technology to reduce the non-renewable energy demand in buildings and reduce peak loads in the grid. Within building applications internal combustion engines, Stirling engines and CHPs based on fuel cell technology are mostly used. The heat and electricity demand here is often characterized by a strong fluctuation over time. The design and control of micro-CHP in buildings is therefore often more challenging in order to achieve its nominal efficiency. In a recently ended research project, different micro-CHP-technologies were evaluated based on on-site measurement campaigns. In practice, micro-CHP is hardly ever used as single technology to deliver the necessary heat. A poor hydronic design can strongly reduce the number of operating hours of the CHP and even its performance, which is influenced by e.g. return temperature. In this paper the performance and behaviour of different technologies are discussed with a strong focus on the part load and start-stop behaviour. The necessary insights are provided with respect to system integration and control and are illustrated with a discussion on the executed measurement campaign in the region of Flanders.

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Abstract. The overall heat demand of a single dwelling, existing out of space heating and domestic hot water production, decreases due to higher insulation rates. Because of this, investing in efficient and renewable heat generation becomes less interesting. Therefore, to incorporate renewables or residual heat on a larger scale, district heating or collective heating systems grow in importance. Within this set-up, the substation is responsible for the interaction between local demand for comfort and overall energy performance of the collective heating system. Many different configurations of substations exist, which influence both local comfort and central system performance. Next to that, also hybrids exist with additional local energy input. To evaluate performance of such substations, a new experimental-based test procedure is developed in order to evaluate these different aspects, characterized by the two roles a substation has, namely as heat generator and as heat consumer. The advantage of this approach is that an objective comparison between individual and central systems regarding performance on delivering local comfort can be executed experimentally. The lab set-up consists out of three different subsystems, namely the central system, the domestic hot water consumption and the local space heating. The central system can work with different temperature regimes and control strategies, as these aspects have proven to have the largest influence on actual performance. The domestic hot water system is able to generate similar tap profiles according to eco-design regulation for domestic hot water generation. The space heating system is able to demand a modular heat load.