Fridges are a complete no-no*, unless you go for gas ones (ex-caravan job) - I'd suggest the old low-tech bowl with water in, cans stood in water, old towel chucked over the top - sun evaporates water, taking with it the latent heat of vapourisation, and cools the cans..........
You could use a pv system, but to do it properly, even just for the fan is going to be horrendously expensive - I'd go at it from the other end - insulate the roof (polystyrene sheets and aluminium foil is cheap), then put in an ex-caravan "roof light" with integral fly screen to take the hot air out - louvred vent in door with screen, job done..........
If you want to "go renewable" get a solar tube from Navitron (under £20), fill with water, stand in the sun, under 2 hours, boiling water!
There's a very simple bit of advice when it comes to pv panels/wind turbines/battery systems -
only use them to produce power for things that can't be powered any other way, as they are SO expensive to do properly you're usually far better to go for bottled gas, woodstoves, rechargeable batteries in radios, lanterns etc........
*I've costed systems, and just to run a simple domestic fridge using renewable energy year-round would cost several thousand quid to do properly - 'fridges and freezers eat power!
