Solar PV Site Selection

Choosing the right site for your Solar PV array is the most important decision you will make throughout your installation. Location plays a vital part in its performance and efficiency of a Solar PV system so it is important to choose just the right spot.

To help you evaluate your site and confirm whether or not it is suitable for a Solar PV, we have designed the following guidelines:

  • PV arrays can be mounted in a range of locations but the roof of a building usually provides the best and simplest site.
  • PV systems are modular, allowing a great degree of flexibility in design and specification. In practice, the size of a system is often determined by the available roof space. A standard 1kWp PV array will occupy at least 8m² of roof.
  • The ideal roof is one that faces south with a slope of around 30-40°. However, other orientations and pitches can be viable with relatively little drop in performance (see table below). 
  • Any shade, such as from trees or neighbouring buildings, can make a large impact on the performance of a PV system. To work effectively, the whole PV array needs to be free from shade for the majority of the day. Do you have any chimneys, trees, or surrounding buildings that cast a shade over your roof?
  • The Good Energy Shop solar PV panels are designed to be mounted on top of an existing or new roof. Although Solar PV systems are not normally heavy enough to cause structural problems, if your roof is in poor condition we would recommend that you undertake a structural survey before proceeding with your installation. If your roof is in need of repair it is worth doing this at the same time as your PV installation to utilise the cost of the scaffolding.
  • The costs quoted by the Good Energy Shop assume a standard installation to a concrete tiled, pitched roof. For slate or clay tiled roofs, approximately £130 extra per PV module will be charged. This is because the PV systems are secured to the roof using stainless steel “roof hooks”. These hooks provide a very robust means of attachment and don’t compromise the weather proofing of the existing roof. Fixing these hooks to concrete tiled roofs is a relatively straightforward process. However, due to the way slate and clay tiles are laid, many more need to be removed to fit the hook, and layers of flashing are needed for weatherproofing - hence these installations are slower and more costly.