Speaking of renewable fuels, green hydrogen may be a wildcard here. Produced through the electrolysis of water using only renewable energy sources, it would make it possible to operate heating systems without any emissions at all. For old buildings, there is the option of converting gas boilers. Due to the lower heating value per volume unit of hydrogen, however, this is far from a technical triviality. Fuel cells are available as an alternative to gas boiler conversion. They can generate electricity and heat at the same time, but the acquisition costs are high. According to a joint study by the Fraunhofer Institutes ISE and ISI, the quantities of green hydrogen available in Germany are still very modest; it would therefore need to be imported for the most part. To prevent this from thwarting the goal of reducing greenhouse gas emissions overall, we need “hydrogen (...) produced as regionally as possible, since long delivery routes can worsen the CO2 footprint,” points out Andrea Appel, project manager for hydrogen development at VDE.
Areas with plenty of sun, wind and water are particularly suitable for generating green hydrogen. Even so, producing it in-house also makes sense here in Germany.
For more flexibility
How is green hydrogen produced?
Green hydrogen is most commonly produced through the electrolysis of water powered exclusively by electricity from renewable energy sources. The most suitable production locations are mainly regions with sufficient wind, water or solar energy potential and the availability of enough high-quality fresh water.
Which regions fit those criteria?
The most promising candidates at the moment are coastal areas in sunny equator regions, as well as Australia and wind-rich Chile. Germany’s new federal government is currently looking into a wide range of possibilities. Strategic partnerships are being developed with Australia and countries in North and West Africa, among others. To keep the CO2 footprint as small as possible, the transport routes should also be short and make use of existing infrastructure where feasible. The main example that I have in mind is green hydrogen production in Scotland.
Does it also make sense to produce in Germany?
Yes, in two respects. It can initially help cover our own power needs but, more crucially, it can also act as a supplement for stabilizing the power grid by establishing highly flexible power plants, which make it possible to react to the fluctuations of more volatile renewable energy sources.