i agree about the solvents etc.
Also the embodied energy of a PV system is very high at the moment.
It would be very interesting to see a system that is very low efficiency but very low cost. This would, be good for many off-griders that have large amount of land, and can build the PV’s themselves etc.
Also taking solar thermal energy and converting that to electrical.
Its good because you can store 1,000 of liters of BTU energy in water underground. 40 ft shipping container for example.
Or you can do the coversion immediatly and staor as electricity.
Or you can store as hydrogen too.
Which leads me to the aspect of the PV’s that output hydrogen NOT electricity.
At the Uppsala University they are doing thsi now.
Basically they have worked out how photosynthesis works and are replicating it.
Having hydrogen is great because you can store it for ever ( apart from leaks 
) and turn it into electricity or Heat when you need it.
Here is a schematic of an example system in Switzerland:
https://sel.me.wisc.edu/trnsys/downloads/trnsedapps/demos/pvhydro.htm
Its nice and simple to understand:
