Interleuven, a partnership of municipalities in the arrondissement of Leuven, together with the municipality of Tervuren, is realising the new and innovative sustainable business park Keiberg-Vossem. For the business park there is the ambition to be as self-sufficient as possible in terms of energy based on solar energy with possible residual heat as extra input. To this end, the site invests in generating and storing renewable energy. _x000D_ The heat produced via PV, solar collectors and cooling of buildings is stored in an underground water basin during the sunny periods. This supply of heat is available for heating during the cold periods. Because of this storage, the heat demand in cold periods can largely be covered by its production during sunny periods. Due to this local production, storage and linking of supply and demand on the site, the impact on the electricity grid is very limited. This way of working prevents ‘inconvenience’ from a new business park to the electricity grid and ensures that energy production can be largely covered by renewable sources. _x000D_ Heat currently accounts for the majority of Flemish energy consumption. For example, in 2019, Flanders needed 122 TWh of heat and ‘only’ 48 TWh of electricity. For small-scale to medium-sized solutions, the main focus for the time being has been on heat pumps and beo fields (storage in the ground). However, the storage of heat in an underground water buffer has the potential to significantly increase and make more sustainable the degree of self-sufficiency in energy for, for example, business parks, residential areas and apartments. _x000D_ Interleuven is not about one night of ice and is now investing heavily in a common infrastructure that will be managed in consultation with the companies. The aim is to promote cooperation between relevant governments and companies and to form a renewable energy community, in which companies and the developer / manager participate. _x000D_ The heat distribution will be operational in early 2025 and one more cycle can be monitored (within the project period). In addition to the experience with the technical installations and the cost-benefit analysis, the data from this monitoring will be shared with other interested companies and authorities via a sounding board group that will be able to monitor the process of realisation periodically via site visits and technical information on the project website. _x000D_ This project is inextricably linked to another ERDF project ‘Op Slag Energierijk’ which regulates the production and buffering of energy on the same site. For the distinction see Annex ‘Project allocation of infrastructure’.