Vonovia, EnerCube, and DFA Demonstrationsfabrik Aachen are all set to launch a strategic partnership for the industrialisation of heat pump cubes in apartment buildings

Aachen, 19 September 2025 – Vonovia SE, EnerCube GmbH and DFA Demonstrationsfabrik Aachen GmbH have entered into a strategic partnership to advance the series production of an innovative heat pump system for apartment buildings, called Heat Pump Cube. Under the banner “Shaping the heating transition – innovation in series production”, over 1,000 Cubes are to be built in Aachen by the end of 2029 and then installed in Vonovia neighbourhoods across Germany. This enables over 20,000 residential units to be heated without the use of fossil fuels in the future.

The launch of the strategic partnership was announced today at RWTH Aachen Campus in the presence of Mona Neubaur, Minister for Economic Affairs, Industry, Climate Protection and Energy for the State of North Rhine-Westphalia.

The Heat Pump Cube was developed by the Austrian start-up EnerCube. It is a compact heating system that combines all key components within a compact cube. The Cube is installed outside buildings in residential areas. This modular solution will replace conventional heating systems in places without connections to local or district heating networks. By providing climate‑neutral heating and hot water to apartment buildings, Heat Pump Cubes will play a key role in the heating transition in existing buildings. The switch to sustainable direct supply also impacts operating costs positively.

After a successful pilot phase, the Aachen-based company DFA Demonstrationsfabrik Aachen GmbH (DFA) will now lead the industrial rollout of this solution. DFA specialises in the fast scale-up of innovative products – from pilot series to full-scale production. Combining their digital expertise, ramp-up experience and production planning skills, they have successfully helped numerous companies move from prototypes to mass production. Thanks to their close ties with RWTH Aachen Campus, DFA combines scientific excellence with practical industrial experience, making it the ideal partner to bring the Heat Pump Cube project to industrial scale.

The Cube is available in a range of power ratings and provides sustainable heating from the ambient air to between 10 and 40 homes. Thanks to its built-in sound insulation, the system is suitable even for high-density housing estates. Its high level of prefabrication significantly reduces on-site installation times and is not rendered impossible by cramped boiler rooms or entrance areas. Maintenance and repairs can be carried out on this external system without any disruption to residents.

“In North Rhine-Westphalia, we are working with determination to establish climate-friendly heating as the new standard – affordable, reliable, and safe. We want a heating transition that benefits everyone – innovative projects such as those by Vonovia, EnerCube, and the DFA Demonstration Factory Aachen are making a significant contribution to this. Every investment in renewable heat makes us less dependent on fossil fuel imports, ensures predictable energy costs, protects the climate, and brings concrete benefits for the people here in North Rhine-Westphalia. As the NRW government, we are providing the necessary impetus and creating planning security,” says Minister of Economic Affairs and Climate Protection Mona Neubaur.

“The energy transition will not succeed without innovation. With our Heat Pump Cube, we offer a modular solution that works quickly and easily in existing buildings. This is important in times of skilled labour shortages. and increasing environmental requirements. Green energy benefits our tenants and the climate alike. With strong partners at our side, we will now roll out this sustainable system in our neighbourhoods across Germany,” says Rolf Buch, CEO of Vonovia SE.

“The technologies for decarbonising existing buildings are now available, and it's just a matter of making use of them. The benefits speak for themselves: a self-sufficient energy system free from fossil fuels, delivering a secure energy supply and generating value right here in Germany,” says Laurenz Sutterlüty, founder and CEO of EnerCube GmbH. “By scaling up our production in collaboration with our partners, we want to make this independence available to everyone. We greatly value our cooperative partnership and are proud to make a contribution to Germany’s decarbonisation with our Cube,” says David Riedl, founder and CEO of EnerCube GmbH.

“Our strength lies in swiftly taking innovative ideas from the pilot phase into robust mass production – and this is exactly what we are doing in partnership with Vonovia and EnerCube. With our digital expertise, ramp-up experience and production planning skills, we are preparing the Heat Pump Cube for full-scale production, making a significant contribution to decarbonising heating systems in existing buildings,” says Prof. Wolfgang Boos, CEO of DFA Demonstrationsfabrik Aachen GmbH.

The pilot project in Donauwörth was a resounding success, achieving energy savings of 40 per cent, and mass production of the Cube has now begun nationwide. By the end of the year, 30 systems are expected to be operational.