3,582 new solar panels will soon cover a field near a Wiltshire village. The military base that secured planning permission this week is not a household name, but the decision sends a clear signal to every UK homeowner weighing solar: the economics have shifted, and the biggest obstacle is no longer cost but connection.
As reported by the Salisbury Journal, the MOD site will host panels capable of generating roughly 1.5 MW – enough to power several hundred homes. That scale is out of reach for most households, but the principle is identical: cheap, clean electricity from a south-facing slope.
What a solar array does to your EPC rating
Energy Performance Certificate ratings are the currency of the home energy market. A typical 3-bed semi with gas heating and no renewables sits at D (band 55–68). Add a 4 kW solar PV system – roughly 10–12 panels – and the rating jumps by 5–8 points, often tipping into C. The Energy Saving Trust estimates a 4 kW system in southern England generates around 3,800 kWh per year. At the current price cap of 24.5p/kWh, that’s £931 in avoided electricity costs annually. Over 25 years, even with degradation, the system pays for itself twice over.
But the EPC uplift matters more than the bill saving. A C-rated home sells for 5–14% more than an equivalent D-rated property, according to estate agent data compiled by Nationwide. For a £300,000 house, that’s £15,000–£42,000 of additional value – far above the typical £6,000–£8,000 installed cost of solar PV.
Who qualifies – and who doesn’t
Not every roof works. The ideal is south-facing, unshaded, and with at least 20 m² of usable space. East-west roofs generate about 15–20% less. The military base has the luxury of open fields; most homes do not. For those with unsuitable roofs, ground-mounted solar – like the base’s system – is an option, but requires land and typically costs 20–30% more per kW due to trenching and foundations.
The catch is grid connection. The base’s 1.5 MW system will need a dedicated transformer and a connection agreement with the Distribution Network Operator (DNO). Homeowners face the same bottleneck: DNOs in parts of the South West and East of England are reporting wait times of 6–12 months for new connections. Ofgem’s latest data shows 40% of small-scale solar applications face delays beyond 12 weeks. The solution is to apply for a connection before you buy the panels – and to check your DNO’s capacity map online first.
What it costs a typical 3-bed semi
A 4 kW roof-mounted system, fully installed with inverter and scaffolding, ranges from £6,000 to £8,000 in 2025 prices. The Smart Export Guarantee (SEG) pays 5–15p/kWh for surplus electricity exported to the grid. At the higher end, that adds £190–£570 per year on top of the self-consumption savings. Payback periods are now 6–10 years, down from 12–15 years a decade ago.
The military base’s system will benefit from zero VAT on installation (the government extended the 0% rate for solar until March 2027) and the ability to sell power via a Power Purchase Agreement. Homeowners get the same VAT relief, plus the SEG. The difference is scale: the base’s panels cost roughly £0.80 per watt, while a household system costs £1.50–£2.00 per watt. That gap reflects installation overheads, not technology – and it is narrowing as more roofers train in solar fitting.
Who pays – and who should act now
Households on standard variable tariffs can apply for solar PV through any MCS-certified installer from 1 April 2025. The 0% VAT rate runs until 31 March 2027, so there is no rush – but there is also no reason to delay. Panel prices fell 15% in 2024 and are expected to drop another 10% this year, according to BloombergNEF. The military base’s planners clearly saw the same trend: buy now, lock in lower costs, and start saving.
For homeowners, the message is simple. Check your roof orientation on Google Maps. Get three quotes from MCS-registered installers. Apply for a DNO connection the same week you sign the contract. The Wiltshire panels will be generating by autumn 2026. Yours could be generating by next spring.
Frequently Asked Questions
In most cases, roof-mounted solar panels are permitted development and do not require planning permission, provided they do not protrude more than 200 mm from the roof plane and are not on a listed building or in a conservation area. Ground-mounted systems usually need planning permission, especially if they cover more than 9 m² or are within 5 metres of a boundary.
A typical 4 kW roof-mounted system costs £6,000–£8,000 fully installed. The 0% VAT rate (down from 5%) saves you roughly £300–£400. The Smart Export Guarantee then pays you for any electricity you export to the grid.
