Commercial solar for Glasgow businesses

Glasgow sits in the SP Distribution licence area, operated by SP Energy Networks, which covers central and southern Scotland. It is a distinct licence from SP Manweb in the north west of England, although the two are run by the same business.

Commercial arrays are applied for under G99 and require approval before energisation, exactly as in England and Wales, since the connection engineering standards are Great Britain wide.

What differs is the wider grid context. Scotland generates a very large share of Great Britain's renewable electricity and parts of the transmission network are known to be constrained, which shapes network planning. For a rooftop array on an existing supply this is usually background rather than an obstacle, but on a larger scheme it is a reason to ask about capacity early rather than late.

Planning in Scotland runs under its own legislation, and permitted development rights for non domestic solar are set out separately from the English regime. Do not rely on English guidance or on a supplier's English planning summary.

The practical position is broadly similar, in that roof mounted arrays on commercial buildings are often permitted development subject to limits, with restrictions applying to listed buildings and conservation areas. Glasgow has a great deal of both, particularly in the Victorian commercial core.

Building standards are also separate, with a building warrant required for work that alters the structure rather than a building regulations application. The installer should be pricing and programming that from the start.

Annual generation per kilowatt peak in the west of Scotland is meaningfully below the south of England, and a business case that quotes a southern yield figure here is overstating the return. Site specific irradiance data should be used rather than a national average.

What partly offsets this is temperature. Panels lose efficiency as they get hot, so a cool, bright day in Scotland produces better per panel output than the same irradiance on a hot day further south, and the summer months are long.

Our own indicative figures use a national assumption, which is optimistic for Glasgow. Treat any output from the assessment on this site as a starting point, and expect the installer's modelled figure to come in below it.

The commercial centre is dominated by Victorian and Edwardian sandstone buildings with pitched slate roofs, dormers and chimneys, which offer little usable plane and frequently sit in conservation areas. These are difficult sites and should be assessed honestly rather than optimistically.

The better candidates are the post war and modern estate: industrial and distribution units along the motorway corridor and to the east, retail parks, and the newer office and campus buildings with flat roofs and clear structural information.

Where the commercial core building has a flat roofed rear extension or a plant deck, that is often the only viable location, and it is worth surveying rather than dismissing the building outright.

We operate across Great Britain through a vetted installer network and hold no Scottish premises. We assess the building, produce indicative figures and match you with an installer who works in Scotland and understands the warrant and planning process here.

That last requirement is not a formality. An installer unfamiliar with building warrants or with the SP Distribution application will get the programme wrong, and the delay lands on you rather than on them.

The assessment is free and carries no obligation.