Thermal Solar vs PV Solar

While most know that there are many renewable energy sources available on the market today. However, many people are unaware that there are different types of solar energy technologies. This includes solar technologies such as thermal and photovoltaic solar. Both involve the conversion of the sun’s rays into energy for the home’s consumption.

Also, there is a difference between utility solar thermal and residential solar thermal technologies. Solar thermal flat plate technology systems differ from photovoltaic cells (PV cells) because solar thermal systems solely produce heat from solar radiation.

In a nutshell, residential solar thermal systems generate heat energy. This heat then warms water within the solar thermal collectors and can be used in various ways to heat a home or water heating.

PV solar power, on the other hand, converts sunlight into electricity using semiconductor materials. That electricity can then be used to perform almost any task in the home. This includes heating, and cooling the home, charging an EV, even powering your Netflix, and keeping the lights on! It can also be sent back to the electrical grid or stored in a battery.

As stated before, there are two different types of solar thermal, residential solar thermal and utility solar thermal. 

With utility solar thermal the main intention is to turn the high-temperature liquid into electrical power. However, residential thermal solar is limited to providing heat energy, not electricity with the use of semiconductors like PV panels. Restricting the functionality of the thermal solar system to summer or warm months, unlike PV that will produce energy year-round.

Currently, solar thermal is used often by large-scale organizations that consume high volumes of hot water. While thermal solar will produce hot water, it does require a significant amount of water, materials, and equipment to install and maintain. These extra materials come with extra cost, making solar thermal more expensive than PV.

For the average homeowner, energy isn’t only needed when the sun is out, but during all hours of the day and night. This is why many PV solar owners choose to pair their system with a battery unit. By storing excess solar energy in a battery you have power regardless of the solar panels actively generating electricity or not. This includes during a grid outage, keeping you and your family safe.

Solar thermal systems however can not store electric energy because they do not produce electricity, they solely produce heat energy. This means that while a PV system generates electricity, a thermal system will only heat water within the collectors. 

There are thermal batteries on the market that are created with the ability to store heat. One example is a large water tank that can be buried underground. This tank is then heated by the solar thermal panels as seen in the illustration below

MIT Solar House thermal battery via Wikimedia

Another way to picture it is as a large tank of water or even candle wax that is heated by coils. These coils connect with the solar collectors. Running through that tank of water or wax is an additional coil. This coil is pumping the heat into your radiant floor or some other heating device you have.

Even though thermal solar may reduce your heating costs, the cost savings from PV solar far outweigh the savings from thermal solar.

The main reason many in Georgia choose to go with solar thermal systems is for pool heating. As it does consume a large amount of energy to heat water. Up until early 2012 heat exchange through thermal solar made economic sense. However, when solar PV panels started declining in cost the line was meet quickly where ROI was better in PV electricity and overall maintenance. 

Nowadays it’s by far more economical to have PV, even just for running an electric heater. However, propane has become more affordable as well. Thermal solar requires constant upkeep to and the longevity of the product is 1/4 of PV. Making the choice to go with PV solar an easy no-brainer for most homeowners.

Another reason many turn to PV systems recently is to take advantage of the federal tax credit (ITC). This year the ITC is 26% for adding solar to a home or business. This incentive will not last forever though, it expires December 31st, 2021.

Turn to the experts in PV systems. Turn to Creative Solar USA TODAY and find out how much you can save with a solar PV system for your home or business!! Set up your free consultation by calling 770.485.7438