Tuesday, January 25, 2011

Elementary School Students Learning the Wonders of Solar Hot Water

Last November we installed a solar thermal system at the Wakarusa Elementary School in Lawrence, KS.  We've been logging data on the systems performance for the past 2 months and have since had a write up in the paper on the success of the installation. Tours given by staff to the "Solar Hot Water Room" have proven to be a successful tool in educating the kids in the function of the solar hot water system, and the importance of reducing energy consumption while also saving money.

Read more and see the video at:
http://www2.ljworld.com/news/2011/jan/25/wakarusa-valley-school-gets-new-solar-thermal-syst/#c1498531

Friday, January 7, 2011

Achimedes & His Friendly Sun Powered Deathray

As the story goes... in 114BC Archimedes used solar death rays to destroy enemy Roman ships that dared to sail too close to the Syracuse by focusing the rays of the sun using a series of giant mirrors. It's true! They even proved that its possible on Mythbusters, so you know it's legit.

Anyways, we may not be torching enemy vessels with our innovative Simple Drainback design, but we are using the sun's energy with good purpose. And we don't use a complicated series of giant mirrors, either. What do we use? One tank, one pump, and one controller. It's that simple:

The sun begins to heat the collectors, and when the collector's sensor is hotter than the tank, the controller turns on the pump, and solar water is pumped up to the collectors. The solar water is then heated as it passes through the collectors. The solar water then flows down to the tank, and heats the water within the tank. The cooler solar water is pumped from the bottom of the tank back up to the solar collectors. As the solar water continues to circulate, the coiled heat exchanger transfers the heat from the tank to the domestic water within the heat exchanger. The tank sensor will signal when the tank has reached its maximum temperature, and will then turn off the pump. The solar water then drains back from the solar collectors down to the tank.

So when hot water is drawn for domestic use, cold water enters the heat exchanger, an then comes out hot. The hot reservoir continues to supply energy to the domestic line until the stored solar water cools.

Then the sun reheats the tank. When the collector temperature drops below the tank temperature, the pump turns off and the water drains back into the tank. The system then waits again for the sun to heat the collectors.

Check out this simple video demonstrating how it works:  http://simpledrainback.com/simpledrainback.swf

(No Romans were harmed in the making of this video demonstration.)



Monday, January 3, 2011

A Solar Water Heater Made of PET Bottles


I found this old article from back in 2007. What a great way to do a little double-time recycling. After guzzling a ton of tasty soda, you can now get even more out of your old plastic bottles by using them to heat your water! Temas says:


"The government of the southern Brazilian state of ParanĂ¡ has been conducting an interesting experiment in environmental design utilizing waste materials.

Since August 2006 state agencies have sponsored projects to construct solar water heaters constructed from used PET bottles and “long life” (aseptic) milk packaging. So far some 3,000 such heaters have been constructed and put into operation in 254 ParanĂ¡ municipalities, in the process diverting about 1.2 million PET bottles and aseptic milk cartons that otherwise might have gone into landfills. It takes 200 PET bottles and 200 aseptic milk cartons to construct the solar water heater array.
It’s estimated that if the heater is used to heat the water for two bathrooms, it can save as much as 120 kilowatts per month."
However, if you're not quite into the extreme DIY approach as our friends in Brazil have so brilliantly developed, check out our approach, developed and designed right here in the heartland of the USA at www.simpledrainback.com