Help with a solar project.

[DFBrews]

When you have power (daytime), run the compressor past its usual cutoff point, which is usually around 0F. R134a boils at -15F, so maybe somewhere around there. The extra 15 degrees is a thermal buffer that acts like a battery. Maybe enough to make the system run battery-less. If you keep the freezer mostly full (water/ice bottles?), your opening losses will be minimal and you'll have crazy good heat capacity.

My chest freezer cuts out at -10 I did a PID controller to bypass the factory thermostat and program it to avoid short cycling. I run my lagering chamber for home brewing this way I have a tub of glycol a pump and then a heat exhxanger in a separate box where i keep the beer