Modelling-based Low Carbon Retrofit House Design

This paper describes three case studies of dynamic simulation in preparation for the low carbon retrofit practice, namely, a pre-1919 terrace house, and a 1970s and a 2000s semi-detached house. The houses are located in Wales, UK. Each case study examines its current performance, assesses the effectiveness of different retrofit strategies, and evaluates the best group of options available. Retrofit cost and time schedules have also been taken into account when making the decision. As a part of the SOLCER (Smart Operation for a Low Carbon Energy Region) project, local and emerging low carbon technologies are encouraged to be used as a demonstration of advanced Welsh construction technologies, and therefore have been considered in this research. It was found that a fabric approach could greatly optimize the energy performance of a poorly insulated house. The application of PV has been shown to reduce the total power demand from the grid by around 90%, and also contributing to domestic hot water heating. A systems based approach has been adopted, combining reduced energy demand, renewable energy supply and battery storage to reduce net carbon emissions by up to 90%, saving total cost by over 200% through operating energy cost reduction and cost earnings for renewable energy generation and export. Above all, great effort has been made to tailor the best retrofit approaches to meet requirements of different properties before starting work on site. The purpose of this paper is to describe the domestic retrofit case studies in Wales, which are intended to be replicable and affordable for largescale application in the future. It hopes to provide some reference to energy-led domestic retrofit programmes in China in relation to the approach to assess the retrofit strategies, identification of the best approach available, and the introduction of new technologies and local Welsh products.