Cooling home brew buckets

I have a 30 liter plastic bucket for fermentation. Is there an easy way to cool the bucket constantly for will say at about 8°C? Otherwise I can only brew ales and wheat beers...

why don't you buy a fridge?

why don't you buy a fridge?

good point. This will make

good point. This will make cold fermentation easy. I have to figure out how the fridge behaves on the huge amount of beer.