How Solar Panels Work

So, how do solar panels work, well firstly we need to look at the different types of solar panel that are in use today.

There are three main types of solar panel in use today:

* Solar PV or Photovoltaic panels

* Solar Thermal Panels

* Solar Hybrid 'PV-T' or 'PVT' panels that combine Solar PV and Solar Thermal.

Looking at these technologies in more detail:

Solar PV (Photovoltaic) Panels

These panels are used to produce electricity. A typical PV Solar panel works by using an array of Photovoltaic cells, which are semiconductor devices that produce electricity when exposed to light. Each cell only produces a relatively small amount of power, which is why multiple cells are used for each panel.

Solar PV cells produce DC (direct current) and for powering normal domestic appliances this must be converted to AC (alternating Current) and at a suitable voltage. An _Inverter_ is used to convert DC to AC and a suitable inverter is an important part of the solar PV system. Likewise there is an electronic control and metering system to control when you use solar power and when you feed electricity back to the main grid electricity supply provider.

Technological development has increased the power efficiency of these devices in recent years and the introduction of PV panels has greatly increased with the introduction of the government Feed In Tariff's or FITs which providing financial inducements to use such panels and reduces the payback periods. To qualify for the FIT scheme the panels and installer must be MCS certified.

Solar Thermal Panels

Solar Thermal systems use pumped fluid circulation to directly harvest the solar heating effect and high temperatures at the solar collectors to heat fluid which is then passed through a solar cylinder or heat exchanger in a closed loop to transfer heat to a pumped home heating system, providing hot water for the home, office or to heat swimming pools! Thermal Solar Panels work with this transfer fluid (often a glycol solution) passing through tubes or across a flat plate mounted on a roof or angled ground array, with a small electric pump to circulate the fluid.


These systems have been around for a long while; however as with solar PV systems there have been developments that have improved efficiency, with the use of evacuated tubes ensuring that the heat captured at the collector is more efficiently collected. There is another financial incentive scheme - the RHI (Renewable Heating Initiative) which may assist in the payback period for such installations.

Hybrid Solar PV-T Panels

Solar PV panels become less efficient as the temperature of the panel rises. An obvious solution to this, is to cool the solar PV panels to ensure that they stay cooler and keep running at high efficiency.

PV-T/PVT Hybrid solar panel systems work by combining the electrical generating properties of a Solar PV system with the heat transfer system of a solar thermal system - bringing the combined benefits of both systems for heating and electricity.

These hybrid systems are fairly recent developments and to successfully combine these systems, the two technologies involved need to be carefully designed. Claims are that for a correctly balanced system it is possible to obtain up to as much as a 40% increase in electrical yield compared to a standard PV panel of the same area and enough free heat for a low energy buildings annual heating requirements.

At Wholebuild we work with a range of professionals in the solar industry. For more information on these systems, browse our site where you will find information from a range of professional manufacturers, installation companies and trade associations.

Solar panels provide renewable energy sources. See the Wholebuild website for more.