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0 pointsmschuster911y ago0 comments

> It certainly does not! (At least, not in any meaningful sense).

The problem is, there are applications that for the foreseeable future cannot be made to work on batteries - airplanes larger than bushcraft and large-scale maritime shipping (the large ocean liners carry upwards of a million gallons of fuel).

Assuming we want to convert these away from fossil fuels - which we have to! - there are only two renewable alternatives: biofuels, which carry serious ethical implications given world hunger and soil depletion, and synthfuels made from hydrogen and sequestered CO2 as base chemicals. The problem is, synthfuels are absurdly expensive because there is no hydrogen market yet so there isn't much happening in scaling up from lab-scale.

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MadnessASAP1y ago

There are some enormous issues regarding hydrogen storage that will need to be resolved before it will be usable on aircraft.

Pressure vessels are heavy, hydrogen is explosive, both of those are incompatible with aircraft.

mschuster91OP1y ago

That's why I said: "synthfuels made from hydrogen and sequestered CO2 as base chemicals."

You need to combine the hydrogen and CO2 into methane and from that into longer-chain liquid hydrocarbons, and that process is complex and energy-intensive even if you use microbes for the job.

MadnessASAP1y ago

Ohhhh.... That is what you said, apologies. Yes I'm all aboard the synthetic fuels train so long as it remains carbon neutral and can run at some reasonable degree of efficiency. Or we figure out how to make enormous amounts of power in a renewable and cheap manner.

jes51991y ago

synthfuels will catch up eventually, the economics keep getting better and there’s really no alternative

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0 pointsmschuster911y ago0 comments

> It certainly does not! (At least, not in any meaningful sense).

0 comments

MadnessASAP1y ago

There are some enormous issues regarding hydrogen storage that will need to be resolved before it will be usable on aircraft.

Pressure vessels are heavy, hydrogen is explosive, both of those are incompatible with aircraft.

mschuster91OP1y ago

That's why I said: "synthfuels made from hydrogen and sequestered CO2 as base chemicals."

You need to combine the hydrogen and CO2 into methane and from that into longer-chain liquid hydrocarbons, and that process is complex and energy-intensive even if you use microbes for the job.

MadnessASAP1y ago

jes51991y ago

synthfuels will catch up eventually, the economics keep getting better and there’s really no alternative

j / k navigate · click thread line to collapse