Most people nowadays are familiar with the concept of solar power – using energy from the sun to generate electricity – but not everyone is clear exactly how it works. That’s why we’ve put together the following guide to the basic science behind our photovoltaic products.

What does ‘photovoltaic’ mean?

‘Photo’ comes from the Ancient Greek word ‘phōs’ which means light, while ‘volt’ comes from the name of the unit used to measure electricity (named for Italian physicist Alessandro Volta). Although the word ‘photovoltaic’ does not have any direct translation into English, it does neatly contain the key concepts involved in solar energy – light and electricity.

How do photovoltaics work?

Electricity is formed from a flow of tiny, negatively-charged subatomic particles called electrons and photovoltaics use energy from the sun to produce this flow. Solar panels and tiles are made up of a lots of thin layers of alternating negatively and positively charged material, typically made from silicon crystals. The negative layers contain lots of spare electrons and the positive layers have too few electrons. By causing electrons to move from the negative layers to the positive layers an electrical current is generated.

Light is made of particles called photons which contain a lot of energy. It is these energy-rich particles which provide the energy to knock the electrons off the negatively charged layers of the photovoltaic cell and transfer them to the positively charged layers. In this way electrical energy can be generated directly from sunlight!

What’s so good about solar power?

You’re probably familiar with some of the arguments for solar power already. Photovoltaics are a great way to reduce your carbon footprint by providing energy in a way that generates no CO2 and they are also highly cost effective, usually paying for themselves within a few short years and providing an excellent return on investment. It’s also worth bearing in mind that as the price of traditional fuels is only likely to increase, solar power will almost certainly become an increasingly competitive option in the future.

One of the most important advantages of solar energy is that it is the ultimate renewable power source. Whatever your opinions on global warming, the fact is that fossil fuels such as oil and gas are finite resources that will one day run out. Sunlight, on the other hand, will never run out (or at least not for the next few billion years!) making it the ideal long term power source. At present, the energy contained in the sunlight that hits the Earth in just one hour is more than enough to meet the whole world’s energy needs for an entire year. This means we could potentially power the entire world using nothing but solar power.

Another factor in favour of solar power is that because it uses sunlight to directly generate electricity, it is inherently efficient. By comparison, coal, gas and even nuclear power stations are all designed to produce energy in the form of heat, which they use to turn water into steam. This steam then drives turbines which produce electricity using electromagnetism. This is a relatively inefficient process which wastes a huge percentage of the energy released by the initial fuel source. By using sunlight to directly produce electricity, photovoltaics result in far less waste.

Metrotile’s photovoltaic products

We offer a range of photovoltaic roof tiles and panels that can be incorporated seamlessly into a new roof or installed on top of an existing roof. Our products are both efficient and far more attractive than the common solar panels you may be familiar with, thanks to their modern design and lower profile. To find out more about the photovoltaic tiles and panels we offer, call us today on 01249 658 514, send us an email or fill out our online contact form.