Chinese astronauts make rocket fuel and oxygen in space

> 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

Why aren't we engineering plants to produce automotive fuel? We ought to at least be able to do diesel.

Plants have very low sunlight conversion efficiency compared to solar farms. If you need chemical fuel instead of electricity, it would still be more efficient to use solar electricity to turn carbon dioxide and water into simple liquid fuels like methanol (usable in spark ignition engines) or dimethyl ether (usable in diesel engines).

> Plants have very low sunlight conversion efficiency compared to solar farms.

Measured how? If nothing else, they seem to be good at carbon capture. And I don't see how you it could account for engineered for plants engineered to store more of their energy as oil.

Measured by the fraction of incident sunlight that gets transformed to usable energy. Solar farms generate about 30 times as much power per hectare as corn farms, assuming that you can use electricity directly:

"Ecologically informed solar enables a sustainable energy transition in US croplands"

https://www.pnas.org/doi/full/10.1073/pnas.2501605122

As a rough estimate, you'd lose 2/3 of that energy if the electricity had to be turned into liquid fuels. That would still mean 10 times greater usable energy produced per acre.

Plants genetically engineered for fuel production might be somewhat more efficient in the future, but future solar farms are also probably going to be more efficient.

For anyone wanting to learn more - the holy grail of Ag engineering would be to increase the efficiency of rubisco, which is the rate-limiting enzyme in photosynthesis - so understandably there’s a ton of research at doing just that.

https://en.m.wikipedia.org/wiki/RuBisCO

Why do we need more efficient photosynthesis in plants? Is it for indoor cultivation?