How Does the Solar Thermal Energy Work?

Solar thermal energy (STE) is one of the most important aspects when it comes to renewable energy sources. With the increasing demand for electricity worldwide, more and more countries are relocating their resources towards renewable energy sources. Solar thermal energy is what makes it feasible, producing electricity conveniently and economically. However, in order to start, we must know how does solar thermal energy works.

Power generation has now been made easier with solar thermal energy. When you hear the name “solar,” the only thing that comes into your mind is “Sun”. Utilizing the sunlight, there are two ways it can be consumed to generate power. One way of doing this is by using solar photovoltaic (PV) panels, while the other way is using solar thermal technologies.

If you are looking to find information about how solar thermal energy works, then this article is going to help you understand the process completely.

What is solar thermal energy?

Eco-friendly energy source, solar thermal energy is created when the sun’s rays are reflected off of a shiny surface which heats up and then transferred for further use. Use it for heating homes, offices, or for any other application; the central aspect remains the same, and that is utilizing the sun’s power.

Producing clean electricity using the sun’s heat, solar thermal energy collects and concentrates the sunlight and projects it towards a single point creating heat needed to generate electrical power.

To make this happen, solar thermal power plants are constructed in order to generate electricity at a large scale. It is different from using PV panels.

PV panels convert sun energy directly into electricity. Whereas solar thermal power plants collect warmth from the sun and heat the fluid. The fluid is then converted into steams, which then power a generator and produce electricity. In this way, no fossil fuel is required, and clean electricity is produced.

Besides generating electricity, the concentrated heat can be used for other purposes as well such as heating water for homes and industries or for heating the space.

How solar thermal energy works?

Solar energy is the cleanest, most abundant, and sustainable energy source available, and harnessing its power in order to meet our requirements is quite effective and simple.

Either used for power generation or heating water for residential or industrial use, STE works in a similar way. For harnessing solar energy, STE uses collectors that are classified into three types.

Low-temperature collectors: These are the flat plates that are mostly used for heating water at a small scale, such as for a swimming pool. These collectors are mainly used for short-term or seasonal applications.

Medium temperature collectors: Used for commercial and residential purposes, medium-temperature collectors are plates slightly bigger in size than low collector plates.

High-temperature collectors: Used mainly for power production, high-temperature collectors utilized mirrors and lenses to collect and concentrate sunlight towards a projected point. Using high temp collectors, the temperature can rise as much as 300 degrees C. However, using the concentrating collectors, as high as 1000°C temperature can be achieved easily.

Solar collectors are placed in a way that they receive direct sunlight and absorb solar energy. It then transfers the heat to a fluid that can be water or oil; it heats up and produces steam.

It is now on you to utilize the heat in any way you want. Other than power generation, STE is also used for air conditioning, cooking, industrial process heat, space heating, and many other numerous applications.


Converting solar energy into heat and then utilizing it for a variety of purposes, solar thermal energy is one of the most propitious renewable and clean energy sources. Giving an alternative to fossil fuels and helping achieve energy independence, there is no negative impact of it on the environment.

Given the benefits it has, more and more people are shifting towards solar thermal energy globally, and this article is going to help you understand how it works. You might have seen a solar plate installed nearby; let us know what you think about how it relates to thermal energy.