Green hydrogen could cover only one per cent of the world's energy needs

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Green hydrogen and synthetic fuels based on it have great technical potential to replace fossil fuels in industrial processes and in the transport sector. Cruise ship owners and airlines, for example, are all too happy to refer to the coming "electrofuels" in order to quickly become climate-neutral.

But from today's perspective, this is hardly feasible within the next 10 to 20 years: because green hydrogen, which is to be produced via electrolytic water splitting using electricity from wind and solar farms, will remain a very scarce commodity worldwide at least until the mid-2030s. At least this is the conclusion of a critical analysis of the current situation.

Short-term scarcity, long-term uncertainty

The study by researchers led by Gunnar Luderer of the Potsdam Institute for Climate Impact Research (PIK) says: Even if electrolysis capacities were to grow as fast in the future as wind and solar energy have in the past, there are clear indications of a short-term shortage and long-term uncertainty in the availability of green hydrogen. Both inhibit investments in infrastructure and application technologies, which reduces the potential and endangers the climate goals.

Luderer and colleagues extrapolated the development of a hydrogen economy on the basis of economic models for new technologies. The growth almost always describes an S-curve with high growth rates at a low level at the beginning followed by a rapid expansion in the following years. In the final phase, however, growth flattens out again as market saturation sets in and slowly approaches a peak. Transferred to the production of green hydrogen with electrolysers, we are now in the initial phase with just 600 megawatts of capacity (2021) and small plants of up to ten megawatts.

In order to get on the path to the climate target of the Paris Agreement with green hydrogen, electrolysis capacity would have to increase by a factor of 6000 to 8000 by 2050. At the same time, the capacities for electricity generation from renewable sources would have to increase about tenfold. With the expansion plans for hydrogen production currently being pursued, the European Union will be able to cover at most one percent of its total energy demand with green hydrogen by 2030. Worldwide, this goal will not even be within reach until 2035. A significant share of 3.2 to 11.2 percent in the EU and 0.7 to 3.3 percent worldwide could only be achieved from 2040.

"Emergency-like political measures" could help

This scenario, which is sobering from today's perspective, shows that green hydrogen could be very scarce in the short term and the supply could still be fraught with great uncertainties in the long term. According to the researchers, more effective policy frameworks are therefore needed. "Historical analogies suggest that emergency-like policy measures could lead to much higher growth rates, which would accelerate the breakthrough and increase the probability of future hydrogen availability," says PIK researcher Falko Ueckerdt.

As examples of such engagement, he cites mobilisation in wars, as in the building of the US Liberty Fleet in World War II, or massive public investment with central coordination, such as the construction of the rapid transit network in China.

This analysis of the ramp-up of hydrogen supply shows that the forces of a free market alone will hardly be sufficient to achieve climate targets, for example in shipping and aviation. Thus, according to the researchers, hydrogen should not be used as an excuse to delay the introduction of other readily available clean options such as electromobility or heat pumps. To effectively reduce greenhouse gas emissions and limit climate risks, all major carbon-free technologies would have to be deployed simultaneously and with full force.

(bsc)