Why hydrogen from bioenergy cannot reduce greenhouse gas emissions
Hydrogen is being strongly promoted by governments, especially in Europe and North America, as part of their ‘net zero’ climate strategies. This is despite the fact that, so far, 98% of hydrogen has been made from fossil fuels, resulting in even more CO2 emissions than burning the same fossil fuels directly for energy. This is even true in the small number of cases where CO2 from hydrogen production is being captured. However, there is growing momentum for expanding so-called ‘green hydrogen’, made from renewable electricity.
The direct greenhouse gas footprint of hydrogen made using wind and solar power is small; however, using such power to make hydrogen will divert wind and solar power from other uses where they would do far more to reduce carbon emissions. This remains the case for as long as the majority of energy is still produced from fossil fuels. Furthermore, heat pumps and electric vehicles are significantly more efficient than switching to hydrogen.
Eventually, assuming meaningful action to reduce dependence on burning carbon for energy, there could be a case for using hydrogen from renewable electricity in certain industries. However this briefing sets out in detail why there will never be a case for using biomass to make hydrogen, regardless of how the biomass is sourced. Bioenergy already has the highest land footprint of all types of energy, because relying on photosynthesis to convert solar radiation to useful energy is extremely inefficient. Most of the energy in biomass is then lost during conversion to electricity or, for that matter, during the three-stage process of making hydrogen from biogas. Furthermore, large-scale bioenergy will rely either on cutting down trees or on converting land to grow energy crops, both of which result in very high overall greenhouse gas emissions.
Hydrogen-from-bioenergy proposals, such as one made by Onyx in Wilhelmshaven in Germany should therefore be rejected.