A one-watt air conditioner

Air conditioning for your pet mouse

Jack and Dah have a goal: no house air conditioning.

Air conditioning is notoriusly inefficient in Thailand, with typical split room-size air conditioners churning out 12000 BTU per hour (3000 watts) of cooling per room, mainly energy spent on cooling sun-heated walls and vaporizing moisture that freely enters the room from outside sources, all at a cost equal to 35 percent of a Thai college graduate's salary. Tankers of oil steam into the Gulf to meet this wasteful demand.

And of course with the light, leaky construction of a traditional Thai house an off-the-shelf machine would be even more inefficient.

So...while hanging around the pub one day I set out to reinvent the air conditioner.

Let's start not with a 3000 watt machine, or even a (say) 300 watt machine that would be arguably sufficient to cool Jack and Dah when they are sleeping. Let's start with the bench machine above, which I built for a couple of hundred baht, a one-watt air conditioner, which meets the following specifications:

cooling capacity (mostly latent): 1 watt
condensate, cc/hr: 1
unconditioned air water vapor entering machine: 20 g/cubic meter
conditioned air water vapor exiting machine: 8 g/cubic meter

Operation of this machine requires about 3600 joules of energy per hour, which can be easily provided by only about 10 grams of ice.

The question: can we effectively scale up, say by a factor of about 300? This would require about 3 kg of ice per hour--seems doable.