Japan Hydrogen strategy and its environmental impact

Japan pledged to be a net-zero carbon emission country by 2050 and made hydrogen and ammonia technology and supply chain one of the pillars of its environmental strategy.

In 2021 METI revised its Hydrogen Strategy, building on its originally published “Green Growth Strategy”. Japan is planning to use 3 million tons per year of hydrogen in 2030 and 20 million tons per year in 2050 (vs 2 million tons currently). Most of this is supposed to be imported. One of the main applications for this hydrogen will be to fire 15 to 30GW cumulative capacity power plants and generate power at 12¥/kWh  and would require ~ 9 million tons of Hydrogen (30GW generating 184TWh with a conversion rate of 20kWh/Kg of hydrogen).

There are three potential issues in this plan that could cast some shade on the environmental impact of this plan.

A local concept of carbon neutrality

The first one, not specific to Japan, is the idea of being “carbon neutral” independently of the rest of the world. Carbon accounting as done by METI is production based and not consumption based. It looks only at the emissions linked to the production process happening in Japan (scope 1 and 2) but not of emissions linked to imported materials nor to those linked to the use of what has been produced in Japan (scope 3) (

This means that if Japan moved all its carbon intensive activities abroad it would meet its goal of being “Carbon neutral”. This would be a fallacy and it proves that the carbon accounting must be done within a “closed system” in the physical sense of the term. This is of course valid at a smaller scale and companies claiming to be “carbon neutral” are usually omitting an important part of their activities. This brings us to the second issue.

“Green” Hydrogen

Japan interest with Hydrogen could be seen from the lenses of the above notion. When used to produce energy, hydrogen does not emit any CO2. Therefore, Japan can produce “clean” energy with hydrogen fired power plants. The burden of carbon emissions reduction has been shifted on the hydrogen producer, in the case of Japan a foreign country.

Today 90 million tons of Hydrogen are produced globally, almost exclusively from fossil fuels, resulting in ~900 million tons of CO2 emissions (IEA global Hydrogen review 2021). That is 10 tons of CO2 per ton of Hydrogen produced. With a fuel value of 33kWh/Kg and a fuel cell efficiency of 60% this is ~450Kg of co2/kWh for hydrogen, similar to burning LNG in thermal power plants. The production of “green” (low carbon) hydrogen is still in its infancy.

But that will not be of much concern for Japan as the emissions linked to Hydrogen production won’t be accounted for in Japan. Thanks to Hydrogen, Japan might end up being “cleaner” while its partners’ emissions rise.

“Green Growth”

The last issue is the commonly referred idea of a “green growth”. It is the idea that GDP and GHG emissions can be decoupled. This might be true at a country level, depending on carbon emissions accounting, but is much more doubtful at a global level. The European Environment Agency published a paper “Growth without economic growth” on this topic. Japan’s strategy for a “green growth”, relies heavily on technologies that do not exist today or that are projected to become much cheaper than they are. This is a problem that is of course not specific to Japan.