Commercial solar for Birmingham industry

The West Midlands licence area is held by National Grid Electricity Distribution, the business formerly trading as Western Power Distribution. The rebrand confuses people, and quotations or older guidance still referring to Western Power Distribution are describing the same network.

A commercial array is applied for under G99 and needs approval before energisation. National Grid Electricity Distribution publish network capacity information, which is worth reviewing early on a larger scheme, because it can indicate whether an export limited design will move an application along faster.

If your site already has a large supply for process plant, you may have more headroom than a comparable site elsewhere. That is one of the quieter advantages of an industrial location and is worth establishing before the array is sized.

Compressors, presses, extraction, ovens, welding plant and machine tools produce a load that runs through the shift and does not care about the weather. Against that background a rooftop array behaves as a direct reduction in import rather than as a generator looking for somewhere to send its output.

Self consumption is the single figure that determines payback. Sites running a full day shift routinely consume everything a sensibly sized array produces, which is why an industrial building in Birmingham can outperform a larger array on a building that stands empty at weekends.

Where a second shift or a night shift runs, generation covers a smaller share of the total, but the daytime portion is still fully absorbed. Storage becomes interesting only when the daytime load runs out before the generation does.

The industrial estates around the city and out towards Oldbury, Smethwick and Tyseley are dominated by single storey portal frame units with long shallow pitched roofs, usually profiled metal sheet. These are close to ideal: large, uninterrupted, structurally understood and easy to mount on.

The complication in older stock is the roof covering itself. Fragile cement sheet, asbestos containing materials and coverings near the end of their life all need resolving before an array goes on, because lifting a system to re roof underneath it destroys the economics.

City centre and Jewellery Quarter buildings are a different problem entirely, with small, subdivided and often historic roofs where the usable plane may not exist. We would rather say so at feasibility than design around it.

A structural appraisal is not optional on an older industrial roof. Purlin spacing, sheet condition, fixings and the additional wind and snow loading all need checking by an engineer, and the answer occasionally caps the system size.

Where the covering has under ten years left, the sensible sequence is re roof first and mount second, and a re roof carried out with an array in mind is cheaper than one that is not. If capital is the obstacle, that conversation belongs in the funding discussion rather than being ignored.

Mounting method follows the covering. Trapezoidal metal sheet takes clamped rails with no penetration, standing seam takes non penetrative clamps, and a flat roof takes ballast, each with different loading implications.

We operate nationally through a vetted installer network and hold no premises in the West Midlands. What we do is assess the site properly, model it against your own consumption, and match you with an installer who has genuinely worked on industrial roofs of your type.

That last point is the one that protects you. A contractor comfortable with domestic pitched roofs is the wrong choice for a fragile cement sheet works roof, and the vetting exists to make that distinction before you are exposed to it.

The assessment costs nothing and produces indicative figures from our published assumptions. Firm pricing comes from the installer after a site survey.