Leslie Science Center Nature House

Danish company AC Sun recently made news with the “invention” a new solar-powered air conditioning system.The new systems are pollution-free, low-noise, and use only 10% of the energy of conventional systems. The only problem is they’ve already been invented, several times over.

Lars Stigel, director of Østjysk Innovation, an investor in AC Sun, spoke with enthusiasm about AC Sun’s design. “It is a groundbreaking technology in relation to renewable energy and energy savings,” he says.

It’s true. There’s no question that solar air conditioning is a technology that deserves its day in the sun. Since central air conditioners are one of the most energy intensive home appliances, the solar-powered alternatives have significant potential for curbing climate change.

However, AC Sun is just the latest in a growing list of companies hoping to capitalize on more efficient and environmentally friendly home cooling technology. In fact, their model won’t actually be commercially available for another year. Who got to the table faster? SolCool (USA), Solar AC (USA), Greencore (USA), Broad (China), and Rotartica (Spain), to name a few.

Sketch of how the AC Sun solar air conditioner worksIt might seem counterintuitive that solar heat would cool a house. But the principles that allow the solar-powered AC systems to operate aren’t anything new. Essentially, the AC Sun unit uses the same Carnot cycle mechanics at work in traditional air conditioning and refrigeration systems. The main difference is that instead of drawing energy from the electric grid, the solar air conditioner uses steam from sun-heated water to drive an engine. A lengthier explanation is available at Solarserver.

Sources: The Official Website of Denmark, AC Sun, Treehugger (for alternate companies).

Photo credit: (top) jhritz via Flickr, under a Creative Commons license; (right) AC Sun.