One of these maybe?
Basically a temperature controlled electric blanket - goes from 10C to 56C - if it works as advertised you could possibly even do a lager with one of these puppies wrapped around the fermenter
It's basically a peltier unit hooked up to a water pump. I'm using one as a makeshift fridge at the moment and can give you an idea of performance based on my unit.
80w of power is not going to give you much of a chiller and to put things into perspective, my unit chews around 145w when it's in chilling mode. Peltiers are also one of the most inefficient forms of refridgeration. 10-15% compared to around 50% for compressor based systems ( although don't quote me on those figures, check for yourself).
Maybe the unit would be good enough if you placed the FVs in a styrofoam box with the blanket wrapped around them. Unfortunately, I don't think the unit is powerful enough to overcome the heat generated by the fermentation.
Another problem I've found with my unit is that in higher ambient temperatures, the unit really struggles. It's great if you want 17-18C and the temps are anywhere between 20-28c. Using it to cold crash the FV it takes a hell of a lot to get it down those last few degrees.
For me it made sense to use the two spare chiller units I had laying around as the price was just right, as in free.
If you want a peltier chiller you are better off buiding your own and getting a massive chip. A fridge would be much simpler, cheaper and would allow you to do lagers if that's your thing. For ales it would probably work but is way too expensive.
Here's a copy of a few notes I took while recently chilling a FV in my budget fridge:
Ambient 23c. Water in polystyro box 26L @ 25c. FV 23L @ 21.5c. Time 8am.
The next day the whole thing is 9c around lunchtime.