Two million. That is the number of solar panel installations now live across the UK, as reported by The Worcester News. The milestone comes a decade after the one-millionth system was connected, and it reflects a surge in demand that began in 2022 when gas prices spiked. For homeowners still sitting on the fence, the question is no longer whether solar works, it is whether they can afford to wait.
Who is installing, and why now
The two-million figure, confirmed by industry body Solar Energy UK, includes both rooftop systems on homes and small commercial arrays. Domestic installations account for the bulk of the growth. The driving factor is simple: the typical 4kW system now costs £5,000-£6,000 installed, down from £8,000 a decade ago, while electricity prices have more than doubled over the same period. Ofgem’s latest price cap sets the unit rate at 24.5p per kWh from October 2024, meaning a household that generates 3,500 kWh a year can save £350-£420 on their bill, assuming they use half of what they generate. The rest can be exported via the Smart Export Guarantee at roughly 15p per kWh, adding another £260 or so.
What this means for EPC ratings and home value
Energy Performance Certificate ratings are increasingly tied to heating and generation. A typical 3-bed semi with gas central heating and no renewables sits at a D rating. Add a 4kW solar array and the rating often climbs to a C, sometimes a B if the roof faces south and shading is minimal. That jump matters: lenders such as Nationwide and Barclays now offer lower mortgage rates for homes with an EPC rating of C or above. The Energy Saving Trust estimates a C-rated home can save £1,000-£2,000 in annual energy costs compared with a D-rated one, though the exact figure depends on insulation levels and heating type.
The catch, grid capacity and battery storage
But the solar boom has exposed a bottleneck. Distribution Network Operators in parts of the South West and East of England have started rejecting new solar applications because local substations lack capacity to handle the extra generation. The government’s Smart Systems and Flexibility Plan, published in August 2024, promises £3.5 billion for grid upgrades by 2030, but that timeline does not help a homeowner who wants panels fitted this spring. The workaround is battery storage. A 5kWh battery adds roughly £2,000 to the installation cost but allows a household to store midday generation for evening use, cutting grid imports by a further 30-40%. Without a battery, a typical system exports about 50% of its generation, money that could be staying in the home.
Grants and schemes, what is available now
The Boiler Upgrade Scheme covers heat pumps but not solar panels directly. For solar, the main support is the Smart Export Guarantee, which ensures payment for exported electricity. Some local authorities offer grants for low-income households, but availability is patchy. The Green Homes Grant, relaunched in a limited form in 2023, prioritises insulation and heat pumps over solar. The most practical route for most homeowners remains self-funding and claiming the 0% VAT rate on installations, which runs until March 2027. After that, VAT reverts to 20%, adding £1,000-£1,200 to the cost of a typical system.
What to do next
For anyone considering solar, the first step is a shading and orientation check. South-facing roofs with a pitch of 30-40 degrees are ideal, but east-west arrays still generate 70-80% of the output. The Energy Saving Trust’s online tool provides a personalised estimate of generation and payback. Installers should be MCS-certified and ideally recommended by neighbours, the Which? Trusted Trader list is a good starting point. Given the grid capacity constraints, homeowners should apply for a connection agreement early, even before choosing an installer, to avoid disappointment. The two-million milestone is a signal that solar is now mainstream. The real question is whether the next two million will arrive before the grid runs out of room.
Frequently Asked Questions
A typical 4kW system costs between £5,000 and £6,000 installed, including VAT (currently 0% until March 2027). Prices vary by region and installer, with some companies offering finance options.
Yes, but output is lower. A north-facing roof generates roughly 60-70% of the energy of a south-facing one. An east-west split array can be more effective, capturing morning and afternoon sun. A professional survey is recommended.
