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298 points Teever | 1 comments | | HN request time: 0s | source
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kevinmershon ◴[] No.45032976[source]
> This is a similar reaction to photosynthesis in plants, which produces glucose instead of rocket fuel.

This is silly, but also begs the sillier question why we aren't bioengineering plants to produce rocket fuel

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andrewflnr ◴[] No.45033082[source]
Why aren't we engineering plants to produce automotive fuel? We ought to at least be able to do diesel.
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DanielHB ◴[] No.45037073[source]
We literally make ethanol from corn and sugar cane. And biodielse from soy.

It doesn't make economic and enviromental sense in most parts of the world (especially corn). In some places they are net-positive on carbon emissions compared to oil-derived gasoline. Tilling the fields, growing, harvesting, processing and transporting often emits more CO2 than the equivalent gasoline produced. Especially the initial tilling of the land to convert it to farmland releases A LOT of CO2 into the atmosphere (this is a one-time thing though).

In the US all (ground vehicle) gasoline sold needs to have 10% ethanol (corn-based), in Brazil it is 20% (sugar cane based). In Brazil almost all cars support 100% ethanol fuel and it is quite common to fuel with ethanol only.

https://en.wikipedia.org/wiki/Ethanol_fuel_in_Brazil

The whole bio-fuel industry is a very complex mix of economics (often requires subsidies to make sense), geopolitical (less imported oil), environmental concerns (mass scale farming soil degradation and CO2 emissions derived from it) and logistical (completely different transportation and refining process).

Fun fact ethanol freezes at a fairly high temperature and mixes with water which makes it not ideal for cold climates and boats. It is quite common for unaware boat owners to f-up their engines by buying car-grade fuel-station gasoline in Brazil.

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matheusd ◴[] No.45039065[source]
> in Brazil it is 20% (sugar cane based)

30% in 2025 for cars (from 27%), 15% biodiesel in diesel for trucks (from 14%).

Source: https://www.em.com.br/politica/2025/06/7183470-governo-aumen...

> The whole bio-fuel industry is a very complex mix of economics (often requires subsidies to make sense), geopolitical (less imported oil), environmental concerns (mass scale farming soil degradation and CO2 emissions derived from it) and logistical (completely different transportation and refining process).

Don't forget lobyying by the relevant sectors!

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1. DanielHB ◴[] No.45039789{3}[source]
And the social implications of converting farmland from growing food to growing sugar cane/corn/soy. It is a VERY complex topic, but it seems overall it is a marginally positive thing for Brazil (even in emissions). While a very negative thing in the US because of all the subsidies required to make corn ethanol viable and overall negative emissions impact compared to oil gasoline.