Research transfer from the road to the building sector

The DLR Institute of Networked Energy Systems significantly supported the commissioning of the prototype regarding questions on electronics and hydraulics as well as hydrogen components. The researchers gathered decisive insights during the first project phase in the DLR laboratory, where they had evaluated the fuel cell system provided by the automotive manufacturer Honda at a specially set up test bench for several months. In a realistic test environment, the system was evaluated here for the first time worldwide regarding its properties in combined heat and power (CHP) using very precisely calibrated and coordinated measurement techniques in high-resolution measurements.

Tests in a realistic system environment

The high practical relevance plays a decisive role in this and comparable analyses, as Dr Hendrik Langnickel, HyNRGCube project leader at the Institute of Networked Energy Systems, emphasises: 'The unique networked laboratory environment at the institute allows us to evaluate the system under a wide variety of requirements: for example, with regard to the electricity and heat demand for residential units or commercial operations across seasonal temperature profiles or regarding energy provision at charging stations based on high-resolution consumer data'. Currently, the DLR researchers are investigating possible later application scenarios for the fuel cell system based on these results, for example in residential quarters. Equally indispensable alongside the technical equipment: years of know-how regarding heat extraction as well as profound technical understanding of cross-sector energy use regarding hydrogen.

Overall efficiency of up to 97 per cent

Langnickel explains why a mature technology still needs to be measured with the originally intended application: 'In a fuel cell system constructed for mobility, thermal output plays a rather subordinate role. Excess heat is usually dissipated into the environment as a 'waste product' in the transport sector, so that no detailed data on thermal performance were known in the project'. When the measurement results from the HyNRGCube project were finally available, it became clear how much potential the intended research transfer from the road to the building sector holds: overall efficiencies of up to 97 per cent were determined at the test bench for the provision of the combined electricity/heat base load. For comparison: with separate supply systems for electricity and natural gas, the efficiency values are around 20 to 40 percentage points lower. Thus, Hy-Energy Cubes are suitable for future energy supply concepts not only because they can provide energy without CO₂ emissions. They also open up new perspectives in terms of efficiency and technology diversity for the heat transition in Germany and the world.

An interesting option for crisis preparedness

The research approach from the HyNRGCube project is a very application-oriented example of how an already mature technology can be used efficiently in a completely different context. Because the 'Hy-Energy Cubes' are designed modularly as compact units, they can be individually configured and thus support stationary electricity and heat demand at specific points. Especially where it comes to supplying critical infrastructures, the concept could make an important contribution to greater resilience and security in the future: 'Hydrogen-operated fuel cells have the decisive advantage that they can provide electricity and heat completely off-grid. In the event of large-scale power outages or disturbances, for example in the natural gas infrastructure, they can also be operated autonomously in island mode in combination with an H₂ storage', says Langnickel. This makes the technology very interesting for crisis preparedness, for example in energy centres or in emergency medicine, as Langnickel adds. 'And in contrast to emergency generators, which remain unused outside of emergencies, the Cubes are already a systemic component of the energy supply in regular operation. This leads not only to continuously efficiently used energy, but also to much higher operating times – and thus to greater economic efficiency.'

Synergy effects for manufacturers and consumers

The financial view of the later practical application played a major role from the start of the project anyway: so far, no cost-effective solutions for stationary fuel cell systems in this performance class are available on the market, because there is no series production with large quantities required for this in this market segment. However, by repurposing already developed systems, any costs still outstanding for product development are eliminated. In addition, advantageous synergies could arise for manufacturers and consumers, leading to cost degression via higher quantities.