Thermal end-uses (space heating, hot tap water, cooling) represent a major part of electricity consumption in Europe and cause consumption peaks, often when electricity is expensive. Hot tap water is the only thermal end-use provided as a base load over a year and that is stored. Space heating and air conditioning are seasonal thermal end-uses with a high residential electricity consumption. They are not stored at the buildings scale to allow peak shaving of the residential electricity consumption. These statements show the interest to develop appropriate thermal energy storages, suitable for buildings, to reduce the electricity bill of end-users. ComBioTES will thus develop a modular compact thermal energy storage (TES) solution for heating, hot tap water and cooling fully adapted for electricity load shifting. A first modular TES will be able to store hot tap water to be converted into ice storage during summer (cooling needs). A second compact latent TES, using high performances (ΔH≈260kJ/kg) bio-based non-aggressive PCM, will store high heating energy amount, for space heating or hot tap water demands. As thermal end-uses in buildings are different regarding seasonal needs, this concept combines the advantage of a modular TES (high utilization rate) with the high volumetric energy density of a latent TES using a bio-based PCM (high compactness: ≥ 100kWh/m3 ΔT=50°C). The ComBioTES consortium and associated External Advisory Board (Idex, Danfoss and Passive House) involve all relevant key players in energy storage and management: RTOs for development and testing infrastructure and SMEs for manufacturing & commercialization of the technology, and representative of potential customers and end users (building owners &operators). In line with IC7, two partners from CHINA (The Institute of Electrical Engineering of the Chinese Academy of Sciences, and The Henan Province GuoanHeating Equipment Co., LTD) will promote the ComBioTES concept in this country.