"The domestic sector faces a range of challenges as the UK attempts to drastically cut its carbon emissions by 2050. A key issue is reducing the overall demand for heat and then decarbonising residual heat loads - which encompasses both demand for space heating and hot water provision. Two non-exclusive means to achieve these goals are: firstly, the diversification of the heat sources serving buildings and communities towards a variety of low-carbon heat sources including solar thermal energy, biomass, waste heat and ground source energy. Secondly, the electrification of space and hot water heating using heat pumps running on decarbonised electricity. Thermal storage would play a key role in facilitating both of these developments, acting as an integrating mechanism for heterogeneous heat sources and decoupling heat supply and demand to mitigate the worst impacts of the electrification of heat. However, there are challenges, one of the most significant is competition for space - as dwelling sizes reduce, the space penalty associated with conventional hot water storage acts as a barrier to uptake. Storage in the future may need to migrate away from the traditional hot water tank at seen at present, towards media such as phase-change materials and storage that makes better use of the existing space and thermal mass in and around buildings, including large scale community storage. An attractive storage option is to integrate future thermal stores into the fabric of the dwelling - fabric integrated thermal stores (FITS).
The aim of this multi-discipline research is to investigate how thermal stores could be integrated into the fabric of future dwellings and communities (both new build and retrofit) and how they would be operated within the local context of accommodating multiple low-carbon thermal energy sources and within the wider context of the decarbonisation of the UK's energy supply. Specific activities include: establishing the operating criteria for fabric-integrated thermal stores (FITS) operating in a future low-carbon energy system; generating prototype FITS concepts, controllers, energy services and heat sensing solutions; performance evaluation of FITS concepts using modelling and simulation leading to selection of best performers for further investigation; construction of scaled FITS prototypes for testing of in-situ performance; gauging user reaction to the concept of using thermal storage for energy services to third parties including demand management; and finally testing of prototype interfaces to FITS with end-users.
The research will generate new knowledge in a number of areas: the architectural integration of thermal storage materials (eliminating the space penalty associated with water tanks); interfacing of thermal stores with heterogeneous heat sources; and information on the acceptability of the participation of domestic heat storage in energy networks. Tangible outputs will include: a range of FITS concept designs - the performance of which will be evaluated using modelling and simulation; two prototypes of promising concepts will be constructed as demonstrators (to test performance in the field); new thermal storage controllers; and energy services will be developed and tested, predicated on the active participation of thermal storage in energy network management.
The work will benefit the construction industry, particularly Architects and Structural Engineers, offering new ideas on the space-efficient integration of thermal storage into buildings. The work will also benefit the building services community and technology developers, providing information on the combination of multiple low-carbon heat sources and the measurement, management and control of stored heat over different timescales. Finally, the work will be of value to utilities and energy service providers, offering insight into the potential of thermal storage to facilitate network support services."