Did you know?

Photovoltaic comes from ‘photo’ from the greek meaning light and voltaic from ‘volt’ which is the unit used to measure electric potential at a given point.


How Much Energy Can I Generate?

How much energy you can generate is affected by a number of factors:


The amount of electricity generated by a solar PV system will vary depending on where you live in the UK. Northern areas receive slightly less energy from the sun over the year.

The map to the left shows average levels of solar gain across the UK and Ireland and you might be suprised to see that south Wales and southern Ireland have the same levels of solar gain as southern England.

For example a 1kWp system will generate less electricity in Northern Scotland than it would in Cornwall. However the differences are not substantial, so solar electricity is still worthwhile even in the northern parts of the UK.

Solar PV doesn't require direct sunshine, only sunlight and will still generate electricity on cloudy days.


Solar PV can be easily incorporated into most houses. The most common option is to use standard solar PV modules in a frame fixed to an existing pitched roof or a tilted frame on flat roof. In this arrangement the panels will slightly protrude from the roof tiles but are still in keeping with the shape of the house.

If you are replacing your roof you can buy solar PV integrated roof tiles and slates that can form part of the weatherproof membrane or structure.

Roof Shape & Size

As solar PV is made up of modules, around 1m x 1.5m, an array of solar panels can be designed to accommodate most size and shapes of roof.

Typical UK installations are around 20m2. For example a 3kWp system could comprise of 16 panels taking up an area of 24m2 & will generate roughly 2500kWh per annum.

Solar PV can also be mounted vertically & horizontally to form part of the wall & roof structures in new properties.


A solar PV system can tolerate shading early or late in the day without much reduction of overall output but ideally it should not be shaded between 10am and 4pm. Nearby trees, chimneys, TV aerials and vent pipes are all common causes of shading and should be accounted for before any installation.

Roof Direction & Tilt

Your roof should ideally face due south but installations facing anywhere to the south of due east and due west are feasible.

Your roof should be pitched at an angle of between 30° and 50° from the horizontal to give the best overall annual performance.

Read more about this here


How much Energy do you need to generate?

The easiest answer to this is to look at your electricity bill, you should find the information on the back or speak to your energy provider. According to the energy saving trust the average household uses around 4400kWh per annum, however our experience suggests that this is on the low side. Remember even if you cannot generate 100% of your energy needs, every unit you do generate is a unit you are not buying from your energy supplier.

Contact us and we can assist in sizing a PV system that meets your needs.



Contact Details

S Magill Contracts
2 Drumgask Rd,
County Armagh,
BT65 5DY




Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
Website: www.smagillcontracts.co.uk


We use cookies to improve our website and your experience when using it. Cookies used for the essential operation of the site have already been set. To find out more about the cookies we use and how to delete them, see our privacy policy.

I accept cookies from this site.

EU Cookie Directive Module Information