"Over the last decade rising energy prices, concerns about global warming and EU energy security have led to increasing interest in domestic scale Renewable Energy Systems (RES) such as solar thermal, heat pumps and biomass technologies. However despite these growth rates, the proportion of RES used for domestic heating and hot water is still under one percent. The main barrier is the high equipment and installation cost of the technology. In addition solar thermal yields cannot always be optimally utilised in existing hot water and heating systems. This is due to the limited size and operating temperature range of conventional thermal energy stores. Increasing the contribution of RES will also necessitate larger thermal stores, which is often difficult due to space and cost constraints. Although higher density Phase Change Materials (PCM) show promising results, they have not been proven to deliver real improvements in domestic applications. In PipeStore, we propose to develop a modular and low cost thermal storage technology, based on a ‘pipes-in-a-pipe’ configuration that can contain a range of PCMs. These will have different melting temperatures, enabling the storage of lower grade thermal energy. This will increase the effective utilisation of a typical solar system by up to twenty percent. Furthermore, a novel actuation and control system will facilitate the use of supercooled PCMs. This will be enable optimal energy storage with a controlled rapid thermal discharge. PipeStore can be scaled and customised to suit any RES in any property. The technology can be positioned in a loft, between walls or in a garage etc. This means that buildings with space limitations can also benefit from RES. The market for thermal storage relating to RES is currently €500 million in the EU and is expected to expand at a rate of at least ten percent per year. Our aim is to capture a five percent market share by 2020 which will be worth €40 million per year."