▲ | _aavaa_ 16 hours ago | |||||||||||||
Water is critical but not hard to get. The energy and cost required to take a m3 of dirty water and turn it into pure water is a rounding error compared to the energy required to hydrolyze it. Yes methane is an environmental problem, even small methane leakages have a large GHG impacts. But the best way to deal with that environmental problem is to not pull it out of the ground in the first place Plus for pyrolysis, you have to deal with the carbon which makes up 75% of the methane by weight. A non-trivial issue. | ||||||||||||||
▲ | XorNot 13 hours ago | parent | next [-] | |||||||||||||
Except we already pull it out of the ground, and people are heavily invested in that process. Working with what we have is the best option here: far easier to enthusiastically go after methane leaks when the industry is otherwise being told "we will buy a lot of your product forever. Which is really the stakes here: if you can "burn" fossil fuels without putting GHG in the air...there's no reason to stop using them at all. In fact we should vastly expand their use. | ||||||||||||||
| ||||||||||||||
▲ | georgecmu 16 hours ago | parent | prev [-] | |||||||||||||
Water is critical but not hard to get. Right. https://en.wikipedia.org/wiki/Water_scarcity You would want to use solar power for electrolysis. In the US, regions with abundant solar power are also the ones that: - have true water scarcity - Nevada and Arizona - have low population and industrial density, so any generated hydrogen would need transported to the point of use. The bigger problem is the energy disparity. Electrolysis of water requires 50 kWh/kgH2 or more. Even a 70% efficient fuel cell would get ~25 kWh/kgH2 -- horrible roundtrip efficiency. With pyrolysis, that equation is exactly inverted: at 9-12 kWh/kgH2, you can generate excess electricity with no CO2 emissions. Plus for pyrolysis, you have to deal with the carbon which makes up 75% of the methane by weight. A non-trivial issue. Exactly. 20 kg of methane costs $3 today, but contains 15 kg of carbon that could be worth $20-$30. It's a non-trivial issue if you hate generating value. | ||||||||||||||
|