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Comment by Reason077 | Hacker News Reader

The Japanese masterplan is to build a national hydrogen infrastructure, with H2 delivered to buildings and homes where it would both power domestic fuel cells and be burnt for heat, as well as provide fuel for Hydrogen fuel cell vehicles.

The primary motivation is energy independence: currently, Japan is the world's largest importer of both coal and natural gas.

As H2 would be supplied by reformation of methane hydrates, it is still a fossil fuel and does not solve carbon emissions. But the idea is that emissions would be substantially reduced compared to the current situation, where a large portion of Japan's energy is supplied by burning imported coal and oil.

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Wouldn't it be easier to create a national methane infrastructure, reforming on the spot where pure H2 is required and methanate H2 when/where/if you can get it from non-fossil sources? Methane is much easier to handle for transport/storage.

It’s definitely an option, although methane reforming will produce carbon monoxide as a by-product and separating that from the hydrogen in a distributed setting (as opposed to centralized plant) is so energy intensive that it would likely offset any savings. Solid oxide fuel cells that run directly on methane are yet another alternative, but their problem is they run at around 600C...

It seems to be easier to upgrade a hydrogen distribution network to use carbon neutral hydrogen than to use a methane distribution network to use carbon neutral methane.

it would be BETTER to produce hydrogen from sustainable non-contributing-to-climate-change-further sources such as electrolysis of water from onsite hydrogen generation such as wind farms, when the grid is not buying, rather than spinning down, produce hydrogen.

Japan has very limited wind energy currently (< 1% of grid generation).

Unlike many European countries, Japan is surrounded by deep waters, which makes constructing offshore turbines more difficult and expensive. But the recent development of floating wind turbines which can operate in much deeper waters means that may change.

However, there is an argument that hydrogen electrolysis is not an efficient use of electricity. By the time you've electrolysed water, transported the H2, and converted it back to electricity in a fuel cell, you've lost at least 70% of the original energy.

So unless there is a lot of surplus electricity generation that would otherwise be wasted, it makes more sense to use it directly where possible. Storage technologies (such as chemical batteries, heat batteries) may be more economic than H2 electrolysis/distribution.

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