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willtemperleytoday at 5:25 PM1 replyview on HN

That infographic says it uses 16-20% more fuel per unit of thrust. That's a significant amount more weight for an aircraft to carry, but because carrying extra fuel also burns fuel, extra fuel use would compound exponentially. This would probably mean significantly more than 20% extra fuel would be required for long-haul flights.


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Animatstoday at 6:28 PM

Ouch.

There's one plantation of under 1000 hectares in Papua New Guinea that makes biodiesel from coconut oil to power their own operation and vehicles on the island.[1] But they don't export. On an island with few energy sources, the process makes sense.

This is more like an industrial process that self-powers from its own waste. Sewerage treatment plants do that - the process produces methane, often enough to power the plant. Not enough to put them into the gas business, though.

Amusingly, corn to ethanol plants in the US do not generally self-power. They consume natural gas to produce ethanol.[2] Net energy gain is maybe 1.3. Only subsidies keep this going. About 40% of US corn production goes into this boondoggle.

Sugar cane, though - that's a win for biomass.

[1] https://www.theguardian.com/world/article/2024/may/10/png-co...

[2] https://en.wikipedia.org/wiki/Ethanol_fuel_energy_balance

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