Innovative Ideas To Keep Cool, Save Energy With much of the U.S. going through a heat wave and the report that the U.S. military spends $20 billion a year on air conditioning in Iraq and Afghanistan, we wondered just what's being done to make air conditioning more energy- and cost-efficient. Michele Norris asks Lloyd Alter, a senior writer for architecture and design for the web site, Treehugger.

Innovative Ideas To Keep Cool, Save Energy

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A few weeks ago, the Pentagon acknowledged that the U.S. military spends a cool $20 billion a year on air conditioning in Iraq and Afghanistan. We all know air conditioning is expensive. I know I'm not looking forward to my utility bill.

All this got us thinking: What's being done to make sure those machines that save us from heat are also saving more energy and more money, whether it's in the middle of a foreign desert or right here in the United States, where much of the country is right now going through a heat wave.

We're joined by Lloyd Alter. He's a senior writer for architecture and design the web site Treehugger. Mr. Alter, welcome to the program.

Mr. LLOYD ALTER (Senior Writer, Architecture and Design, Thank you.

NORRIS: Now, we've seen a push towards energy efficiency machines in the home and at work, things like washers and dryers and refrigerators. And as a result, those machines use far less energy. Do we see the same innovations for air conditioners on the whole?

Mr. ALTER: Yes and no. There is a lot of innovation going on. They are getting more efficient. But, ultimately, the real problem with air conditioning is it's all about laziness. People used to design houses with carefully placed windows for cross ventilation. Walls were thicker so that they would absorb heat in the day and give it off at night. And with air conditioning, everybody just got lazy. They figured they could just throw more money at it.

So you'll find houses that have huge, big picture windows facing south in the summertime, in a hot climate, when they then have to pay more money to move the heat back out that they let in.

NORRIS: But there are people who have been busy trying to find innovations in air conditioning and let's talk about some of those things.

There are a lot of new machines or contraptions on the market that seem to be designed to keep an individual or a single room cool, instead of an entire structure - the idea of putting central air conditioning on ice.

Mr. ALTER: Well, putting it on ice is actually the right word for a wonderful technology called the Ice Bear. So what it does is it runs the equipment all night long, making a huge block of ice. And then in the daytime, it actually uses the melting ice to keep cool instead of actually the air conditioning condenser.

NORRIS: What about building materials that absorb heat during the day and then release it at night, these so-called phase change materials?

Mr. ALTER: This is a wonderful coming technology that they're actually, in Germany, building right into your drywall. And it's, again, if you imagine when ice melts it absorbs a great amount of heat. But ice isn't melting right at a convenient temperature for you. So the chemists manufacture the material so that the phase change is right around room temperature.

So that at night when it gets cooler the stuff will solidify and give off heat. And in the daytime, when it's hotter, it will absorb the heat. And the fact that they're putting it right into the drywall - albeit still very, very expensive - will mean your whole house will work like that.

NORRIS: What about solar-powered systems?

Mr. ALTER: Ah, this is the Holy Grail I've been looking for, for so long. The trouble is, if you try and run a regular air conditioner off solar power, you have to have acres of solar panels to do it. But in China, one company, they're making the cooling cycle actually work on the power of sunlight. And it's very efficient and I think that's the real answer to the problem.

NORRIS: Lloyd Alter is a senior writer for architecture and design for Lloyd Alter, it's been a pleasure to speak to you. Thank you very much.

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