The Halfords type and similar ones that appear in Aldi & Lidl at £30 or so are cooled by Peltier effect. It's a semiconductor device that gets hot on one side and cool on the other when switched on. The hot side releases heat via a grille, sometimes aided a little fan blowing air over it to the outside of the box, the other side cools the interior. The cooling effect is pretty small for a reasonable current so the best way to use them is to fill them with well refrigerated stuff and keep it cool, which it will do reasonably well.
We use one for days out to keep the picnic and drinks cool on the journey there but TBH an insulated box or bag(s) with a reasonable number of ice packs in will do just as well for a day. Chucking an ice pack or two into the cooling box doesn't hurt either.
They do draw enough current that you really only want them on when the engine is running. They probably use as much electricity as a typical small caravan fridge but they are much less efficient and far less effective.
You can buy proper fridges with a compressor (and possibly evaporator types) e.g.
www.amazon.co.uk/Alpicool-K25-Refrigerator-Campervan-20%C2%B0C-20%C2%B0C/dp/B08BX7Q4YF/
if you need something more effective.
Don't expect too much.
|
