Hydrogen: would it pass a change of scale?
Air Liquide recently announced the construction in Canada of a PEM (Proton-Exchange Membrane) electrolyzer with a 20 megawatts (MW) capacity to produce carbon-free hydrogen. “Carbon free” means that the electrolyzer does not release greenhouse gases (GHG) itself during the hydrogen production, unlike the steam reforming of natural gas that is the current main way to produce hydrogen and that is highly GHG intensive. Consequently, the positive impact on climate change depends on the way the electricity is generated. Connected to low carbon emitting power plants, hydrogen can be used as energy storage facilities for power production, power-to-gas solutions and transportation fuel. Without considering any economic/cost related issues, it seems to be a possible key element for a transition to a low carbon economy.
To discuss the credibility of such a scenario and to provide some order of magnitude, let’s imagine that French road transport massively migrates to fuel cell cars and trucks. In 2017, this represented about 600 billion vehicle-kilometres, meaning that we need to provide enough energy for such distance. Current cars fed by hydrogen (H2) roughly need about 1kg of H2 for 100km and 50-60 kwh are required for the production. The easy to estimate total of additional low carbon electricity production to fit yearly transportation needs is 330 TWh. In 2017, total electric production was 554TWh and if we decide not to add new nuclear capacities, at current wind (resp. solar) efficiency of 20% (resp .13%), it is about 184 GW (resp. 275 GW) of additional capacities to be installed. With a trend of yearly new capacities of 1.7GW (resp. 0.6), it is only a matter of centuries…
Certainly, technical improvements are not taken into account and we are at the very beginning of the technology, but we can’t consider hydrogen as a panacea and the solution is certainly multifaceted. First out, being the need for travel to decline or potentially rethinking cities.
Emeric Nicolas, Head of Data Science Dpt.
Sources: Beyond Ratings, UNECE, Air Liquide, Enerdata