Invisible and Affordable Solar Water Heating for Your Home

Anyone who doubts the persistence of good old-fashioned American innovation is advised to consider the Greenbuild International Conference and Expo, an annual convention showcasing the newest and most ingenious green tech products made by American hands. This year¡¯s expo, held in the tremendous Phoenix Convention Center, comprised over 1,800 exhibit booths, making it the largest convention in Greenbuild history.

According to Treehugger.com, which covered the event, of particular interest this year was the Greenward Ridge Vent, a nifty piece of solar-heating equipment that can be fitted to any standard shingled roof. The Ridge Vent collects solar energy and uses it to heat water; but it is the thrift with which the vent performs its task that makes it remarkable. The Ridge Vent collects solar heat trapped in a home¡¯s attic; the heat flows through the Ridge Vent around PEX plastic tubes, heating an ethylene-glycol-and-water mixture that is then pumped into a heat exchanger, preheating the home¡¯s tap and fixture water even before it gets to the water heater. In other words, the vent effectively takes wasted energy and puts it to good use: a concept both simple and ingenious.

Close-up of demonstration Greenward Ridge Vent.
It is the Ridge Vent¡¯s innocuous design that makes it so appealing. Unlike the typical solar collectors, which can make your home look like a lunar space station, the Ridge Vent is barely noticeable. That¡¯s not to say you won"t notice its effect. According to Greenward, "With an average attic temperature of 120 degrees F., the Greenward Ridge Vent can reduce your energy consumption by just over 12 million BTUs a year and reduce your CO2 emissions by just over 1,400 pounds annually." The fact that heating water by solar energy costs one tenth as much as heating it by electricity means that you stand to save considerably on your electric or gas bill.

The Greenward Ridge Vent is just one more example of brilliant solar technology to be produced this year. Conventions like the Greenbuild Expo and the annual Solar Decathlon have provided public forums for emerging solar technology, and have garnered well-deserved attention from the media. Advocates of solar (and other clean) energy will recall that despite stalled climate legislation across the globe, the Cleantech Group has predicted a bright future for green technology. We look forward to it.