Solar PV vs Solar Thermal: A Basic Explanation

solar panels on roof image

Solar energy represents only 1.5% of the total US energy supply, but it is undoubtedly the one most frequently referenced when the average person thinks about clean and renewable energy. With more and more people looking to switch to solar power for their energy needs, we thought it would be a good idea to explain that there are actually two primary types of technology that can be used: solar photovoltaic (PV) and solar thermal, with the former being the type most commonly deployed on residential rooftops these days. In this blog post, we’ll explore the differences between these two solar technologies.

Solar Photovoltaic (PV)

Solar PV technology converts sunlight directly into electricity using photovoltaic cells. These cells are made up of semiconductor materials such as silicon, which absorb photons from the sun and convert them into electrons. The electrons are then channeled into a circuit and used as electricity.

PV technology is the most commonly used solar technology in the world today. It is widely used for both residential and commercial applications, and it is known for its efficiency and reliability. PV panels can be installed on the roof of a building or on the ground, and they require very little maintenance once installed.

Solar Thermal

Solar thermal technology, on the other hand, uses the heat from the sun to generate electricity or heat water. There are two primary types of solar thermal technology: concentrating solar power (CSP) and solar water heating (SWH).

CSP technology uses mirrors or lenses to concentrate sunlight onto a small area, heating up a fluid such as water or oil. The heat is then used to generate steam, which drives a turbine and generates electricity.

SWH technology, on the other hand, uses solar collectors to heat water directly. The collectors are typically installed on the roof of a building and consist of tubes or panels that absorb sunlight and heat up the water inside.

While solar thermal technology is less common than solar PV technology, it has some advantages over PV. For example, it is more efficient at converting sunlight into heat than PV is at converting sunlight into electricity. Additionally, solar thermal systems can be used for both electricity generation and water heating.

Which Technology Should You Choose?

When it comes to choosing between solar PV and solar thermal technology, there are a few factors to consider. If you’re looking to generate electricity for your home or business, solar PV technology is probably the better choice. PV systems are more efficient at generating electricity than solar thermal systems, and they can be installed in a wider range of locations.

On the other hand, if you’re looking to heat water for your home or business, solar thermal technology may be a better choice. Solar water heating systems are more efficient at heating water than PV systems are at generating electricity, and they can be a cost-effective way to reduce your energy bills.

Both solar PV and solar thermal technologies have their advantages and disadvantages, and the best choice for you will depend on your specific needs and circumstances, not to mention the availability of tax and other incentives that can help make an investment in solar not only good for the planet, but also good for you wallet. There are significant climate and economic factors that will vary from region to region and home to home. Solar is an important part of our (meaning humanity’s) collective decarbonization pathways, but individuals looking to solar have a staggering amount of information and options to navigate. As an initial step, it is essential to understand your state (or city’s) and utility’s solar programs and you should plan on consulting with a few professional installers who can help you determine which technology is right for you.

If you’re a high school students interested in climate change, decarbonization, renewable energy, including solar, have a look at one of our Sustainable Summer programs.