I'm really surprised that a Peltier device can pull that off. Mind you, the max temp difference between ambient and a carboy is 20F, so your house would have to be quite cold to be able to lager in a carboy. I wonder why a bucket is so much more efficient (max 35F difference)... the mass and high specific heat of the glass?
I'm very suspicious of their energy use claims though. For instance, why do their calculations assume the same duty cycle for their device and a freezer? If you're trying to cool to the rated maximum with the Peltier device (which is the only reasonable assumption given that it can only drop the temp 35F max) I would expect the duty cycle to be much higher than 25% Also, they don't include the 10W idle draw in their calculations, which would add another 65.7 kwh per year to the energy bill. Seems to me they're massaging the numbers.
