Solar thermal is the forgotten renewable energy resource according to solar thermal experts. When we think of solar, we think of photo voltaics (PV). However, solar thermal is much more efficient that PV and can stand the test of time, while allowing us all to become energy independent.
A couple of weeks ago this examiner attended the monthly Colorado Renewable Energy Society’s meeting. This meeting and May’s meeting are both free and open to the public. The meeting was held on April 28th and featured Colorado solar thermal industry leaders at the City of Broomfield’s library at 3 Community Park Road.
The first to speak was Broomfield City and County Assistant Manager Kevin Standbridge. He was proud of the money invested in the renewable energy projects throughout their city and county.
The library has a PV array, which was the first solar project Broomfield began by buying electricity from SunEdison via the PV panels a couple of years ago. (See article on SunEdison project on the Western Slope.)
Broomfield has three different solar projects. According to Colorado Energy News, the city and county will be saving an estimated $450,000 over the next 20 years by investing in “green” energy.
The array at the library consists of panels on the roof and ground producing 102 kilowatts (kW). The library also has solar thermal.
Onto solar thermal, and the first to speak on the subject was Laurent Meillon, Director of Capitol Solar Energy. Their systems work with water, (can be mixed with plant based glycol to prevent freezing), circulating through copper tubing to capture solar thermal heat to either create hot water for household or commercial use or for radiant floor heating. Their system interfaces with a forced air heater in a heat exchange with solar thermal. It also utilizes the excess summer heat to mix with cool water in radiant flooring; thereby keeping the home or business at a constant comfortable temperature.
The forgotten renewable surpasses PV in efficiency. While PV has an efficiency level of 17-30%, solar thermal has 70% energy efficiency according to Meillon.
When the sun heats the water, glycol or oil on rooftops, it is stored in a tank in the basement of the building or home.
Solar thermal can provide 60% of the hot water in a typical home, so it is practical to have a backup water heating device of about a 40 gallon capacity according to Meillon.
However, think of it! Up to 60% of the time, your home or business is not using natural gas or electricity from your local utility. Your home or business is not paying a dime to heat water for bathing, washing and/or heating 60% of the time! As long as the sun is shining, your home or business is acquiring free energy from that fiery ball in the sky with solar thermal.
Solar thermal is at the forefront in China and not a forgotten renewable as in the United States. According to Meillon from 2007 data, China is installing over 80% of the entire solar thermal globally. Meanwhile, the U.S. makes up only .5% of all the solar thermal installations globally.
This is far cry from the days when the U.S. was a leader in solar thermal in the 1970s during the Carter administration. In those days and even today, citizens receive a federal tax credit for installing solar thermal panels on their homes and businesses.
The leaders of solar thermal advocated for their “green” alternative to nuclear power. Nuclear power, as stated in a previous article by this examiner, has many deadly consequences in meltdowns, being prohibitively costly to build and maintain reactors, and costly to manage waste from the reactors. These experts promoted concentrated solar over nuclear power as a safe and “green” alternative.
However, according to Bill Lowstuter, Founder and CEO of Sun Trac Solar, natural gas not nuclear power is the biggest competitor to solar thermal in Colorado.
His business installs primarily in education facilities and commercial buildings. He stated that their solar thermal systems are most ideal in industrial food service and food processing businesses. He added that there is a quick return on investment on solar in Colorado of 1-2 years.
Lowstuter stated that it is difficult to compete with natural gas because it is readily available in Colorado and out-competes solar thermal, mainly because of tax credits and subsidies the natural gas industry receives.
Furthermore, Colorado utilities do not give consumers any rebates for solar thermal installations and Xcel Energy just halted their PV solar rebates.
In addition, natural gas receives higher tax subsidies than solar thermal. Meanwhile, natural gas extraction has its potential negative impacts on the environment and Colorado’s most precious resources, water and clean air.
There are three types of solar thermal collectors: flat plates, which produce temperatures up to 140̊ Fahrenheit, evacuated tubes up to 200̊ F and more efficient than flat plates, and finally the tracking troughs, which are miniature concentrated solar panels producing temperatures up to 600̊ F with heat oil.
Sun Trac uses the flat plate collector with the trough system inside, which can run at higher temperatures for longer periods of time. Lowstuter stated that their systems do not overheat and even when it is only 50̊ F outside the collectors can produce water at temperatures of 100-200̊ F.
Sun Trac manufactures their solar thermal systems in Golden and they are looking for installers.
The next speaker was Mike Wilson with Sol Source located in Lafayette. Wilson talked about the large concentrated solar system found in Southern California and he also believes that concentrated solar may replace nuclear power.
He added that the Governor’s Energy Office (GEO) is giving rebates on solar thermal up to $3,000.
Wilson would like to see more usage of solar thermal in our state, since Colorado is one of the best locations for efficient and effective solar thermal all year round. He suggested feed in tariffs as Germany now implements. He encouraged citizens of Colorado to write to legislators and the Public Utilities Commission (PUC).
Overall these leaders and advocates for renewable energy believe that solar thermal is one of a variety of ways that we can become energy independent and lessen our negative impact on the environment.
Learn more about CRES upcoming events.
Want to do a DIY solar thermal project on your home? Check out: http://www.jc-solarhomes.com/solar_hot_water.htm