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by georgecmu 3046 days ago
It's a puff piece (who's his PR firm? I want to talk to them!)

Those interested in the topic should acquaint themselves with the policy context and the state-of-the-art.

[1] https://energy.gov/eere/fuelcells/doe-technical-targets-hydr...

[2] https://www.nrel.gov/docs/fy14osti/60528.pdf

The DOE goal for cost of distributed / dispensed hydrogen is $4/kgH2. Cost of centralized production is estimated at half that even with electrolysis. I find it suspicious that there aren't any specific production cost estimates cited; just vague comparisons to unspecified existing technologies.

Also, methane is a far better source of hydrogen than water (less energy required to break down the molecule for the yield of twice as much hydrogen). Steam-methane reforming (95% of industrial hydrogen production) gets you hydrogen from both methane and water, but is a huge CO2 emitter (9-10 kgCO2/kgH2).

I'm personally a big proponent of thermal decomposition of methane [3]. Theoretical energy consumption is only 1.29 kWh/kgH2. if you can use a non-emitting source of energy, there's no CO2 emission. Carbon falls out as a solid and capture and sequestration is free. If you can make a valuable carbon (e.g. graphene) along the way, then you're set and there's no way electrolysis will ever be competitive.

[3] https://www.nrel.gov/docs/fy02osti/31351.pdf

1 comments

One thing about methane, though, is that it's a nonrenewable fuel. Unless you're talking about it as a storage intermediary (for example, if it's synthesized from CO2 and H2O using renewable energy).