Bringing down emissions from buildings to zero might be the hardest nut to crack for the European Green Deal. With heating and cooling in buildings being responsible for 40% of energy consumption and 36% of emissions, the importance of its decarbonisation cannot be overestimated. As the current annual renovation rate is below 1% and more than 70% of heating in buildings is supplied by old and inefficient boilers, buildings are unanimously recognised as a hard-to-decarbonise sector by the Renovation Wave Strategy, the Energy Efficiency Directive and national strategies.
A range of solutions is available to supply efficient and increasingly renewable heat to and in buildings, including reducing demand, direct electrification, district heating, cogeneration, solar thermal, and geothermal. Yet, key challenges to the timely and cost-effective decarbonisation of buildings include the seasonality of heat demand, the variability and limited capacity of renewable electricity supply, constrained electricity grids, customer choice and cost.
Due to the heterogeneity of the building stock and climatic conditions in Europe, it is clear that a one-size-fits-all approach will not work. Direct electrification of heating and cooling is not economically feasible in different types of buildings. In such cases, gaseous or liquid energy carriers will continue to be needed.
There is an ongoing debate between policymakers and stakeholders on the role of hydrogen to supply buildings with heat and electricity. This could be done via district heating, individual boilers or micro-cogeneration systems. A micro-cogeneration system running on hydrogen and fuel cells generates heat and electricity inside a building. It provides multiple benefits to the end-user as well as to a rapidly decarbonising energy system.
Firstly, fuel cell micro-cogeneration (FC micro-CHP) systems are very energy efficient, thanks to a total efficiency over 90%, allowing for a very cost-effective heat and power production. Furthermore, it turns energy consumers into prosumers giving them the flexibility to generate heat and electricity when they need it. Households and businesses can become largely independent from the grid with their own FC micro-CHP unit.
On the system level, several fuel cell micro-CHP units can act as a power plant and cover residual electricity demand, at times of peak demand or insufficient wind and solar generation. With the electrification of heat, power grids will be increasingly constrained in winter as peak demand will more than double in many countries. When the uptake of electrified solutions is complemented by fuel cell micro-CHP roll-out in the same neighbourhood or region, expensive power grid updates can be reduced or avoided. By bringing the point of power generation and consumption closely together, up to EUR 2,000 of grid reinforcements can be avoided for each 1 kWel of micro-CHP installed.
Accelerating a deep decarbonisation of buildings will require a profound integration and decentralisation of our energy system. Fuel cells and other hydrogen-based solutions can be a large and cost-effective contributor to that. With gas grids covering more than 50% of the energy needs in buildings across Europe today, we already have a wide network in place to deliver a decarbonised gas.
Several national and regional authorities have already signed the Joint Declaration on Stationary Fuel Cells for Green Buildings. Sign if you want to support the uptake of this decarbonisation solution!
