Hydrogen-powered vehicle (archive image): a substitute for fossil fuels?
Photo: Bernd Wüstneck / dpa
Seldom have such high hopes been linked to a small molecule: Hydrogen is considered a key element for the climate-neutral transformation of the economy, housing and transport. Researchers at the Potsdam Institute for Climate Impact Research (PIK) are now pointing out, however, that it is not the appropriate means of replacing fossil fuels in all areas. "Hydrogen-based fuels are an impressively versatile energy source - but their costs and the associated risks are also impressive," said Falko Ueckerdt, lead author of the study.
For most sectors, the direct use of electricity, for example in electric cars or heat pumps, makes more economic sense. Hydrogen-based fuels should therefore primarily be used in areas that can hardly be electrified directly. These included "long-haul flights, parts of chemical production, steel production and possibly some industrial high-temperature processes," said Ueckerdt.
Fuels and fuels produced with hydrogen (e-fuels) are easier to store and transport than electricity or pure hydrogen. According to the study, however, the problem lies in the large amounts of green electricity required to produce hydrogen. In the German electricity mix of 2018, the use of hydrogen-based fuels in cars, trucks or airplanes would cause around three to four times more greenhouse gas emissions than the use of fossil fuels.
The study presented in the journal Nature Climate Change sees the use of hydrogen as a long-term perspective.
With carbon prices rising, hydrogen-based fuels could likely become cost-competitive by 2040.
However, given the urgency of reducing greenhouse gas emissions in order to stabilize the climate, 2040 would be too late for all those sectors in which direct electrification is possible.
mic / dpa