The price cap will hit £1,923 in October, the highest it has been since the energy crisis began. For a typical 3-bed semi using 3,500 kWh of electricity a year, that is about £160 a month just on power. Against that backdrop, the Financial Times asks whether solar panels still make financial sense (see the original FT article). The answer, for most homeowners, is yes, but the maths has shifted.
What the FT analysis gets right
The FT piece correctly notes that the Smart Export Guarantee (SEG) rate has fallen sharply. In 2020, Octopus Energy paid 15p per kWh exported. Today, the best fixed-rate SEG tariff from Octopus is 12p, and some suppliers offer as little as 4p. That cuts the income side of the solar equation. But the FT also highlights a countervailing trend: retail electricity prices have risen 50% since 2021. Every unit of solar power you use at home replaces a unit bought at the cap rate, currently 27p per kWh. That self-consumption saving is where the real money sits. Energy Saving Trust figures show a typical 4 kWp system in southern England generates about 3,800 kWh a year. If you use 50% of that directly, you save £513 on your bill. Export the rest at 12p and you earn another £228. Total benefit: £741 a year.
The EPC bonus most buyers miss
What the FT article touches on only briefly is the EPC impact. A home with an EPC rating of D typically needs a score of 69–80 to reach C. Solar panels alone can add 8–12 points, depending on roof orientation and shading. That jump unlocks access to green mortgages, Nationwide offers a 0.25% rate discount for EPC A or B homes, and Barclays gives up to £1,000 cashback for C-rated properties. On a £200,000 mortgage, that 0.25% cut saves £500 a year in interest. The Department for Energy Security and Net Zero confirmed last month that homes with solar sell for an average of 4% more than equivalent homes without. For a £250,000 semi, that is £10,000.
But the catch is timing. The current SEG rates are not guaranteed to hold. Ofgem reviews the minimum export price every year, and the trend is downward. The government’s own advisory group, the Climate Change Committee, has warned that falling export revenues could push payback periods beyond 15 years for some households. That matters because the typical solar system warranty is 25 years on panels and 10 years on the inverter. You need to be confident you will stay in the house long enough to recoup the upfront cost, typically £5,000–£7,000 for a 4 kWp system installed.
What the FT misses, grants and regional variation
The FT analysis is London-centric. In Scotland, where solar irradiance is 30% lower than in Cornwall, a 4 kWp system generates only about 2,800 kWh a year. That drops the annual saving to roughly £550. But Scotland offers the Warmer Homes Scotland programme, which covers up to 100% of solar installation costs for eligible low-income households. In England, the Great British Insulation Scheme does not currently include solar, but the Home Upgrade Grant (phase 2) does, up to £10,000 for off-gas-grid homes. The FT also omits battery storage, which can push self-consumption from 50% to 80%. A 5 kWh battery adds £2,000–£3,000 to the system cost but boosts annual savings by about £200, cutting payback from 12 years to 10.
What to do now
Households considering solar should act before the SEG review in December 2025. Get at least three quotes from MCS-certified installers, the Microgeneration Certification Scheme is non-negotiable for SEG eligibility. Check your EPC first; if your home is already rated C or above, solar’s EPC benefit is smaller. For those in the bottom four EPC bands (E, F, G), the best first step is often loft insulation and cavity wall fill, which cost £300–£1,000 and can cut heat loss by 25%. Once the fabric is efficient, solar becomes a pure electricity play. Applications for the Home Upgrade Grant in England reopen on 1 April 2025. Don’t wait for a cheaper inverter, panel prices have fallen 80% in a decade and are unlikely to fall much further. The right time to buy solar is when you can use the power yourself, not when the export rate peaks.
Frequently Asked Questions
Yes, because the main saving comes from using the electricity you generate at home, replacing grid power at the current price cap rate of 27p per kWh. Even with SEG rates at 12p, a typical 4 kWp system saves £500–£700 a year.
A standard 4 kWp system with installation costs between £5,000 and £7,000, depending on roof type and location. Adding a 5 kWh battery adds £2,000–£3,000. Grants like the Home Upgrade Grant can cover up to £10,000 for eligible off-gas-grid homes.
