Cool your house with chemical reactions

MENLO PARK, Calif.--Solid, meet liquid.

Acvio, a company out of Finland showcasing its technology at the Nordic Green conference this week at SRI International in Menlo Park, says it has come up with an air conditioning system that consumes 60 percent to 70 percent less power than conventional systems.

The energy savings comes because Acvio's system doesn't require a compressor to make cool air, the traditional engine inside air conditioners. It works like this: Warm air from the outside is collected and funneled toward a solid. The heat melts the solid and the melting process takes heat out of the air. That cooler air is then cycled inside to cool down the inside of a home or office. You can also use it in server rooms. Half the electricity in today's data centers gets used to power the air conditioners. (And you thought it was to run the machines in the snack room.)

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"Instead of a compressor, we use hot and humid air," said CEO Kari Moilala, during a meeting. "The energy is taken out of hot air."

Acvio's system does require fans, but these can be run by solar panels, Moilala said.

The system can also be used to heat a building by running the process in reverse, but it works better as an air conditioner.

Moilala wouldn't say what the material is that goes from solid to liquid, but it isn't water. A few U.S. companies like Ice Energy are cooling buildings by converting ice to water.

Heat exchange systems--those that shuttle heat and cold back and forth like this-- have been around for a while but are improving in the face of increasing electricity prices. Another one to check out is Hallowell International, which has an air conditioner that also works as a heater in cooler climates.