Are solar panels only useful in the summer? As a leading installer of solar panel systems all over Scotland, this is a question that we hear on a very regular basis.

It is an understandable concern. As skies darker, days shorten, and inclement weather becomes all too common, it is hard to believe that something which relies upon the light of the sun could be cost-effective for more than a few months each year.

However, the fact is that it is a complete misconception that solar panels do not work during the winter.

The UK, which has a much cloudier and more temperate climate, produces solar panel efficiency levels on par with warmer countries such as France and Spain, and colder northern countries such as Germany produce well over 5% of their energy from solar sources alone.

How then, is this possible? Well, it all comes down to the way in which solar cells work as they are affected by seasonal weather changes a lot differently to what many people believe.

How do solar panels work?

The key to understanding why solar panels can still be cost-effective during the winter is in understanding exactly how they work.

Solar panels are constructed from photovoltaic (PV) cells, special units that are usually made out of silicon.

These PV cells contain electrons which become energised when impacted open by photons, otherwise known as light particles.

This energy is then converted into electrical energy within the panel itself that can be used to power your home.

Does cold matter?

As demonstrated above, it is photons, and not heat, which makes a solar panel function.

This means that there is just as much potential for energy production from sunlight in freezing temperatures as there is during a heatwave.

In fact, your solar panels will likely become even more efficient on a cold day as like the majority of other electrical appliances, solar cells actually operate best in colder conditions.

Contrary to what most people would imagine, extremely hot weather will actually harm the efficiency of solar panels, as the energy difference between the photons and electrons will be much smaller.

The ideal conditions for solar energy production are when the difference in energy between the photons and electrons are at their greatest, and this is most often the case on a cold but sunny day with few or no clouds.

The short answer, explained in rather more complex terms above is that no, the cold does not harm the efficiency of solar panels.

What about the weather?

Ok, so sure, a cold sunny day is perfect for solar panels but how many of them do we get in a Scottish winter?

The real concern about solar panel ownership during the winter is the snow, rain, and clouds that fill the void between us and the sun.

Snow

Snow is possibly the only weather condition that can completely stop the production of energy by your solar panels.

If enough snow settles on the surface of a panel the sun’s rays will be unable to reach the solar cells beneath until it is cleared or melts away.

Luckily the smooth surface of an angled solar panel is not particularly prone to holding snow for a prolonged period and even the smallest increase in temperature will likely see the snow slide off.

This process will be sped up even further by the fact that for maximum performance solar panels will be installed facing the sun so the snow nearby will be the first to melt.

Rain and cloud

Overcast conditions will result in a significant drop in solar panel performance but as long as there is light, your panels will continue to produce energy.

It is estimated that on a cloudy day solar panels tend to produce around 10-25% of what they would on a clear day.

Rain, on the other hand, has no negative effect on solar panels besides the act that it is accompanied by clouds, and can even help to improve performance by washing away the dirt and debris that has accumulated over time.

Shorter Days

Many people point to the shorter daylight hours that we get here in Scotland as a reason that solar panels may not be a worthwhile investment but in contrast we are also blessed with much longer daylight hours in the summer than many other countries.

This means that although you may indeed see lower production from you solar panels in the winter, although there will still be a significant amount, the excellent performance in the summer alone is enough to make them a sound financial investment.

For more information on solar panel installation, or to arrange a free home suitability survey, get in touch with Greener Energy Group today and our expert team will be delighted to help.