Huh, this looks promising:
https://www.hotspotenergy.com/solar-air-conditioner/
Especially:
100% Solar Air Conditioner
NO AC Power or Grid Connection Required
SEER
On pure AC power when no free solar energy is used, official SEER is >22. SEER is “Seasonal EER” and is a way of describing an “average EER” and considers that the system operates under part-load conditions a majority of the time. Currently, there is no official test standard for testing SEER or EER based on whether or not the energy is paid for. However, if you perform a SEER calculation and include only the paid energy, this calculated SEER can be as high as SEER 75 or above when using solar along with AC backup power.
Ordering, Pricing & Specifications
The Manufacturer’s List Price on the ACDC12C is $1,895. ACDC18C cost is $2195. Solar panels, etc., are not included. Complete kits are also available, please call or email to discuss kit options.
Independent of grid, so no need to prevent electricity backfeed / have a transfer switch because this system never touches house wiring in the first place.
Obviously would need to figure in cost of solar panels… 
