solar panels for manufacturing in Portsmouth

Portsmouth’s manufacturing base

Portsmouth Naval Base still sets the character of industry in this city. The dockyard and the defence and marine supply chain that grew up around it feed a spread of precision engineers, metal fabricators, electronics assemblers and marine sub-contractors, most of them tucked into the northern half of the island and the mainland fringe around the M27. Voyager Park, off the A27 near the old airport, mixes production units with distribution and trade counters in clear-span steel portal frames. Next to it, the Airport Industrial Estate occupies part of the former airfield and carries a lot of light-industrial and manufacturing floorspace on wide, low-pitched roofs. Walton Road, out towards Farlington, adds further workshop and trade units, while Lakeside North Harbour beside the M27 anchors the larger commercial and business-park end of the city.

These occupiers share a problem. Industrial electricity has become one of the biggest bills a Portsmouth plant cannot easily control, and a mid-size site here runs at roughly £38,000 a year on grid power, with energy-intensive operations paying a good deal more. At the same time, the naval and defence primes that buy from local firms now ask suppliers to report Scope 2 emissions and show a credible reduction plan, which turns carbon disclosure into a condition of the next contract. Rooftop solar answers the cost side and the reporting side together, which is why enquiries from this part of Hampshire have picked up.

What on-site solar does for a Portsmouth plant

A machine shop on Voyager Park or a fabricator off Walton Road draws most of its power in the working day, when CNC beds, welding sets, extraction and compressed air are all running. That daytime shape is what makes solar work on a manufacturing roof: the electricity is produced at exactly the hours the plant is using it, so it displaces grid import at the full retail rate rather than being sold back cheaply. For a single-shift Portsmouth operation with some early and late overlap, a well-sized array typically self-supplies between 40 and 70 percent of annual demand, and refrigeration-heavy or multi-shift sites push higher still.

Sizing follows the load, not the roof. We pull at least 12 months of half-hourly meter data and size the array to a large slice of peak daytime demand, so generation lands on the site rather than spilling onto the export meter. That usually points a Portsmouth manufacturer towards something between 150 kW and 600 kW, though larger sites near Lakeside North Harbour run well beyond that. Every kilowatt-hour generated on your own roof is also one taken off exposure to wholesale price spikes, which a finance director values as much as the headline saving.

Funding, tax relief and local support

Portsmouth City Council has committed to a 2030 net zero target under the Portsmouth Climate Emergency Plan, two decades ahead of the national statutory deadline, so the planning authority treats rooftop PV on industrial buildings as routine and it usually falls under Permitted Development Rights where the building is not listed or in a conservation area. The city’s Solent Freeport status adds a further layer: qualifying investment inside the designated tax sites can attract enhanced capital allowances, which is worth checking against your site boundary before you finalise the business case.

On the tax side, solar PV counts as plant and machinery, so the Annual Investment Allowance lets a limited company expense the first £1m of qualifying spend in year one, giving up to roughly 25 percent effective relief straight away. Larger, energy-intensive Portsmouth sites in eligible sectors may also draw on the Industrial Energy Transformation Fund or improve their position under a Climate Change Agreement, since on-site generation reduces metered grid consumption directly. We map the combination that fits your site and flag which routes are live before you commit; the detail sits on our grants and funding page, and you can sanity-check the numbers on the cost breakdown.

Connecting to the grid across South East

Portsmouth falls inside Scottish and Southern Electricity Networks’ distribution area for the South East, and that Distribution Network Operator has to approve any commercial array of real size. A G99 application is needed for connections above 17 kW per phase, which covers effectively every manufacturing install, and the study response commonly runs to around 65 working days. The connection date itself, though, can land anywhere from 6 to 18 months out on a constrained network, so it tends to be the longest single item in the whole programme rather than the physical build.

We handle that by getting the DNO application in early, alongside the structural survey, so the connection clock is already running while the design is finalised. Where the export capacity will not arrive in time, we phase battery storage into the scheme so the plant starts self-consuming its own generation from commissioning and picks up the export agreement later. On older units around the PO postcodes, a legacy single-phase or capacity-limited supply can cap array size, so the connection review happens up front rather than as a nasty surprise late in the day.

Example: a engineering and metalworking business site in Portsmouth

Take a representative engineering and metalworking business near Portsmouth, the kind of sub-contract shop that machines, welds and fabricates to order for the naval and defence chain. The unit has a 1,400 square metre roof over a portal-frame workshop and a daytime-heavy load from machining, extraction and a large compressed-air system. A rooftop array of 230 kW, roughly 425 panels, fits across the available roof and generates in the region of 211,000 kWh a year.

Because the load is concentrated in the working day, self-consumption sits around 75 percent, so most of that generation replaces grid import at the full rate while the modest surplus earns under the Smart Export Guarantee. On those figures the array saves about £30,000 a year, and simple payback comes in near 6.6 years, with the panels carrying a 25-year output warranty so the return keeps running long after the system has paid for itself. Just as usefully, the generation data drops straight into the customer sustainability audit the shop’s primes now expect. These are representative figures for a site of this class, not a named client, and any real proposal is built from your own half-hourly meter data, which we share in full so your finance team can stress-test it. Model your own version on the savings calculator.

The wider Portsmouth area we serve

Beyond the island itself, we cover the manufacturers ringed around Portsmouth Harbour and the mainland to the north. That takes in Gosport across the water, Fareham at the head of the harbour, and Havant and Waterlooville up towards the A3, plus the workshops and trade units around Southsea. Coverage runs west along the coast to Southampton, the nearest city, so a manufacturer with plants in more than one location gets the same design, installation and reporting standard on every site.

Wherever your operation sits, whether on Voyager Park, the Airport Industrial Estate, along Walton Road, near Lakeside North Harbour, or on a smaller unit in the PO districts, the first step is the same. We run a desk feasibility study from your half-hourly meter data and roof drawings, come back with a sized and costed proposal, then survey the site before the G99 application and contract. If you want to know whether your Portsmouth building stacks up, request a quote and we will give you straight numbers. You can also browse our other manufacturing locations to see where else we work.