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Time to change your thinking

Time to change your thinking

Stop thinking like that.

I’ve been reflecting on the pace of change lately, especially after reading about some new photovoltaic and solar thermal collectors that will make you forget about any solar collector that you’ve seen before. posted a report August 30 about a Swiss invention, the Solar Sunflower, that goes by the acronym HCPVT, for Highly Efficient Concentrated Photovoltaic Thermal. It boasts total efficiency of 80%.

The collector, which actually does look something like a giant silver flower, is made up of a collection of slightly curved, round solar concentrating panels that make up the “petals” of the flower. The panels focus sunlight to the equivalent of “5,000 suns.” Ok, so concentrating solar collectors aren’t new. But here’s the new stuff.

The collector is a joint venture of Airlight Energy and IBM Research. One of IBM Research’s products is a gallium arsenide PV cell. They’re really expensive, but when you have a concentrating collector you don’t need a lot of them to produce power. As a result, each “sunflower” can generate 12 kW. The downside of a concentrating collector is that it produces a lot of heat. Fortunately, IBM has experience cooling supercomputers and has developed a way to feed water through micro-channels right on the back of a computer chip. That’s the technology that’s being applied with the Solar Sunflower, which can generate 12 kW of thermal energy (40,946 Btuh) at temperatures to 90°C or 194°F.

I also recently finished editing the fall edition of Radiant Living magazine that we published for the Radiant Professional Alliance.

The issue includes an article on site-sourced thermal energy management (SSTEM) by James Schenck. The key to SSTEM is storing energy in water, and lots of it. We’re not talking about a 120-gallon tank in the mechanical room. This about large underground tanks that can store energy contributed by multiple sources over long periods of time so you don’t need to worry about running out of stored energy tomorrow. You mate that with a water-to-air or water-to-water heat pump that can extract energy out of the tanks down to 32°F. If the ambient temperature is -20°F, that makes a difference.

The heat sources can include solar collectors, fluid coolers/ambient absorbers, earth loops, graywater, biomass, and building integrated thermal siding or roofing. All of these energy sources, stored in a big heat sink, operate independently of the loads. In elements, when applied to SSTEM systems, become “100 percent optimal bin hour capable.” In other words, because the heat sources and the heat sink elements operate independently from the loads, you can, as the old saying goes, make hay while the sun shines.

You can check out Mr. Schenck’s article in the digital edition of Radiant Living at

Coming up at this year’s Comfortech Conference and Expo in St. Louis, RPA Executive Director Mark Eatherton will be giving a talk on how to blend radiant heating and cooling with forced air heating and cooling.  Sometime to make the customer comfortable, you have to change your thinking.

Finally, I’m going to have the opportunity at the end of this month to visit with Nest Labs in Palo Alto, California, to check out the Nest thermostat and their other residential smart products. The Internet of Things will eventually be worth trillions of dollars — yes, that’s trillion with a T — and I’m looking forward to finding out more about Nest’s take on smart homes and smart buildings.

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