The Wikipedia article on photosynthetic efficiency[1] is informative. TL;DR: since extracting carbon from CO2 is energetically unfavorable, it needs to be powe

The Wikipedia article on photosynthetic efficiency[1] is informative. TL;DR: since extracting carbon from CO2 is energetically unfavorable, it needs to be powered by sunlight. Typical plants are 1-4% efficient in their overall usage of solar energy to generate sugars, and it's not possible to get above ~11% without using some totally different biochemical process. Some plants are adapted to be more efficient than others, but I think we can be pretty confident that there are no simple tweaks to radically increase efficiency that billions of years of evolution haven't already stumbled on. [1]: https://en.wikipedia.org/wiki/Photosynthetic_efficiency https://en.wikipedia.org/wiki/Photosynthetic_efficiency