If your only energy source was solar then nights could be a problem, but if you can connect to the grid and be paid for power you produce like they do in Germany and a few places in the US, then it could make sense. Here you can find a lot of information on watts produced per solar panel:
https://www.google.com/search?num=50&newwindow=1&safe=off&site=&source=hp&q=how+many+watts+are+produced+by+a+solar+panel&oq=how+many+watts+produced+&gs_l=hp.1.0.0i22i30l2.1443.14211.0.19783.33.25.2.3.3.0.472.3856.0j4j5j3j2.14.0.msedr...0...1c.1.60.hp..14.19.3902.0.SeNg5EXy8Nw
A friend told me that about 250 watts per panel under ideal conditions, and that seems right from what I see at these sites. Thus about 80 panels could provide 20KW, this is considerably less than 2 acres. In Germany, which I’m sure has a lot less sun than your location, the farmers put panels elevated and with spaces between rows. Then they grow crops underneath, and if it were very sunny like in the south, then some protection from excessive sun exposure for more tender plants would be the positive result. For small uses like the room with the bed, batteries can store power for later use.
That’s about what I thought.
At night, he could confine the cooling to just the bedroom with a window unit.
Otherwise, he could sleep in the bathtub, with some nice soothing cold water.