Can Artificial Photosynthesis be a Fossil Fuel Alternative?

[T.O.E Dream]

If we can achieve artificial photosynthesis, might it replace fossil fuels once and for all? Can it also be an effective engine in vehicles?

 

[Bob S]

Do you have any suggestions for a new energy source or a new photosynthesis cycle? The Calvin photosynthesis cycle is very complex, and requires ~ 24 photons to make a single C₆H₁₂O₆ (energy of oxydation ~ 29 eV), but we don't know any more efficient cycle (except C4).
Bob S

 

[DaveC426913]

Is there something wrong with our current solar panels? Is there any reason to think that photosynthesis would be more efficient in converting solar flux to energy?

 

[Lsos]

I read somewhere that photosynthesis is very efficient.

Now, I'm seeing sources that say it's very inefficient. Around 6% at maximum.

If that's the case, then I don't see solar panels getting replaced anytime soon...

 

[T.O.E Dream]

Is there a way to make solar panels more efficient?

 

[mgb_phys]

Is there a way to make solar panels more efficient?

Yes lots of ways. if you also want them to be cheap, reliable, long lasting, manufacturable , easy to install and maintain as well then it gets a bit trickier

 

[Bob S]

If we can achieve artificial photosynthesis, might it replace fossil fuels once and for all? Can it also be an effective engine in vehicles?

I have also calculated ~6% for combustible biofuels such as miscanthus or switchgrass (C4 photosynthesis). C4 crops are more efficient combustion biofuels than Calvin cycle crops, except at higher latitudes. They also release CO2 and other pollutants back into the environment when combusted.
Switchgrass releases about 7500 Btu heat energy per pound when burned. This is equivalent to about 7.9 megajoules per pound, compared to 120 megajoules per gallon for gasoline. So anyone using switchgrass in an automobile with a 20 mpg rating would have to put ~ 1 pound of switchgrass into the firebox per mile while driving. Switchgrass might be better used at a public electricity utility; 1 pound of switchgrass could generate about 0.7 kilowatt-hours of electricity for electric vehicle battery charging.
Bob S