Differences between thermal and photovoltaic solar panels
Solar panels are one of the most modern and effective devices that we can find when it comes to the use of renewable and non-polluting energies. Did you know that these were invented by NASA almost 70 years ago? That’s how it is, The first solar panel was developed by NASA engineers in 1954 for space use.. These panels were invented in order to autonomously power the communication equipment of the satellites.
Differences between thermal and photovoltaic solar panels
Much has happened since then… Solar panels today have nothing to do with those large prototypes with poor performance, with very high manufacturing costs compared to the amount of energy they were capable of providing. Currently we can find two types of much more modern and sophisticated solar panels, each with its own different characteristics and functionalities. These are the photovoltaic and thermal solar panels. Next, we analyze what are the main differences between solar and photovoltaic panels.
What are solar thermal panels?
Solar thermal panels, also known as solar collector panels or collectors, are panels that are used to obtain thermal energy. These panels work by taking advantage of solar radiation in order to generate thermal energy in the home by heating water. The operation of the thermal solar panel is simple, what happens is that the heat carrier is heated —or liquid that runs through the solar panel ducts—. This liquid, which can be water or glycol, or a mixture of both, then passes to the heat exchanger where the energy is transferred to the water for domestic use while the liquid in the panel recovers its usual temperature. These solar panels can be of two types:
- Flat collector solar thermal panels: Physically it is very similar to the photovoltaic solar panel. These have a rectangular box that is covered by a sheet of glass and five remaining faces that are opaque and thermally insulated. Inside the box is the metal plate attached to the conductors through which the heat carrier flows.
- Empty tube solar thermal panels: These solar thermal panels have a more complex structure. They have an outer shell and several empty tubes. In them are linear collectors. The heat transfer liquid circulates through the mast to which the different empty tubes are attached. These thermal solar panels make better use of solar energy.
What are photovoltaic solar panels?
Photovoltaic solar panels are solar panels used to obtain energy through solar radiation. In this case, the energy obtained is converted into electricity by taking advantage of the conductive materials with which the photovoltaic cells of the panel are made. What happens is that the flow of energy generated is transformed into electricity. Likewise, depending on the installation that is carried out in this type of solar panels, we can distinguish between two types of photovoltaic solar panels. These are:
- Photovoltaic solar panels on the network: These are the photovoltaic solar panels that are connected to the general electrical network.
- Isolated photovoltaic solar panels: These are photovoltaic solar panels that are installed in locations where the general electrical network does not reach. These panels need a battery to be able to store energy.
Differences between solar and photovoltaic panels
As you will have verified, the difference between solar panel and photovoltaic is great. Each one has its way of working and its specific main function. Although we can also find other less notable differences that we explain below:
- Differences in function: Photovoltaic and thermal solar panels are totally different panels. Although both types of panels take full advantage of solar energy, photovoltaic solar panels are used to obtain electricity while thermal solar panels are used to obtain thermal energy.
- Utilization: The use and demand for photovoltaic and thermal solar panels also varies from one type to another. In fact, the difference between solar and photovoltaic panel is that the photovoltaic solar panel is more used than the thermal one. This is so because the photovoltaic solar panel represents a very high cost reduction in the electricity bill, it can also be used in isolated areas where the general electricity network does not reach.
- different materials: Although both are solar panels, the truth is that photovoltaic and thermal solar panels are made of different materials. Photovoltaic solar panels are made from photovoltaic cells which are themselves made from silicon. Silicon is a metalloid widely used in computing for its conductive properties. Photovoltaic solar panels can be made of mocrystalline silicon (the silicon is transformed into a single crystal) or polycrystalline silicon (this type of glass is much easier to obtain, although the amount of energy used is slightly less). However, in the case of thermal solar panels, the material used in their cover is a transparent tempered glass with a dark hue that allows better heat capture, as well as favoring the greenhouse effect.
- Useful life: Many times the doubt also arises about the useful life of photovoltaic and thermal solar panels. The truth is that this difference between solar panel and photovoltaic is very prominent. While solar thermal panels typically have a lifespan of approximately 10 years, solar photovoltaic panels have a lifespan of approximately 20 years. Now, thermal solar panels usually make better use of energy compared to photovoltaic solar panels. For this reason, both choices are correct. In the end it all depends on the needs and the use we are looking for.
- Facility: The installation, on the other hand, is easier to carry out in thermal solar panels, while in photovoltaic solar panels it is a little more complex. Photovoltaic and thermal solar panels hardly need periodic maintenance. Photovoltaic solar panels can save the energy of the house of 50 or 60% of the total.
These are the differences that exist between both types of solar panels, thermal and photovoltaic.