How Do I Know If My House Is Suitable For Photovoltaic Solar Panels?

There are millions of homes in the UK that are suitable for photovoltaic solar panels but how do you know if your home is one of these? Solar PV works by converting light into electricity, the main source of light being the Sun. Conversely Solar hot water panels work by absorbing the heat energy from the Sun.

Solar panels are usually fixed to the roof, they can be mounted elsewhere but for practical reasons roof mounted panels are the main practical solution for homeowners. This means that your roof needs to be facing towards the Sun. This may seem obvious to most but in the UK the Sun moves across the sky from east to west and is located in the southern part of the sky most of the time. For this reason your roof needs to be facing south.

Does my roof face South?

It can be difficult to tell whether or not you have a south facing roof. Most people will have two roof surfaces, one facing towards the street and the other facing towards their back garden. Most people do not have a compass so to get a rough idea you can see where the Sun is in the sky. On a sunny day at about midday to 2pm see where the Sun is in the sky, this will be approximately south.

Solar panels should be effective as long as your roof is facing within 90 degrees of south. For them to be at their most effective up to 30 degrees from south is recommended. The best way to check it to see if one of the free solar panel installers would accept your home for one of the free solar panel offers. If they accept you then you have an ideally situated home.

Other factors to consider for Solar PV

There are other practical considerations other than having a south facing roof. Solar panels are quite large and even a modest array will need about 24 square metres of roof space. Most companies will do a free survey and will tell you the size of the array that you can adequately fit. A typical 1960's semi detached house could fit about 8 solar panels on the roof.

Overshadowing can be a major factor. Some types of solar systems do not cope well even when just a small part of the array is in shadow. Shadowing can occur from a chimney stack, tall trees especially tall evergreen trees and of course other tall buildings.

To a certain extent your solar set up can be designed to cope better with low light conditions and shadowing. This can be done by choosing the right type of solar panel in conjunction with a good inverter that manages each panel individually rather than in a series.

Is your roof suitable?

Once your panels are installed they will likely be there for 40 years. The system will require maintenance but more importantly your roof may require maintenance. If you have an old roof that has never been maintained then it may be work considering getting the roof fixed first before installing the panels. It may be costly to remove the panels at a later date.

If you are considering getting your roof retiled then it may be worth considering solar roof tiles rather than panels. Solar tiles can replace ordinary roof tiles and do the same job as solar panels. The benefit is that they are less obtrusive and you can maximise your roof area for solar PV, essentially covering the entire south facing portion of your roof with solar PV tiles.