Using the sun to heat water (or other liquids) – which is called solar thermal energy – is an old technology that hasn’t been fully explored to see how it can contribute to reducing emissions associated with heating in homes and other buildings.
At the moment solar thermal energy installations in the U.S. number about only one tenth of the number of solar photovoltaic installations. In a solar thermal energy system, like the one at a residence hall of Creighton University in Omaha, Dan Gearino writes “vacuum-sealed glass tubes [that] are converting the sun’s energy into heat, as opposed to electricity.” The system “converts the sun’s energy into heat to increase the temperature of a liquid. The liquid circulates in a closed loop between the roof and a water storage tank in the building. The process transfers heat to the water, which is then used in sinks and showers.” The energy savings are not massive but will contribute to a lowering of emissions for the University.
Although not that popular or frequently used in the U.S., solar thermal energy is big in countries that get a lot of sun (Cyprus, Greece, Israel) and where energy costs are relatively expensive. It’s not that solar thermal energy is inherently better than solar photovoltaic but rather that when looking for solutions it is important to not get tunnel vision and decide that only certain approaches will work. Rather we should keep in mind that “everyone is better off if there is competition and innovation in a variety of zero-emission heating technologies.”
From “The Daily Difference” 12/14/23 by the Carbon Almanac. To read more or subscribe click HERE.
