UK Solar
Knowledge Quiz

The Smart Export Guarantee (SEG) requires all licensed electricity suppliers with 150,000+ customers to pay you for every unit of renewable electricity you export to the national grid. Unlike the old Feed-in Tariff, there is no minimum rate — suppliers set their own tariffs competitively. Octopus Energy's Outgoing Octopus tariff currently pays around 12p/kWh (Q2 2026). You must use an MCS-certified installer and have an export meter (or smart meter in export mode) to qualify. There is no deadline or cap — you can join at any time after installation.

Most residential solar installations are covered by Permitted Development rights and do not require planning permission, provided: the panels do not protrude more than 200mm from the roof surface; the highest point of the installation does not exceed the highest point of the existing roof; the system is not on a listed building, in a Conservation Area, or a World Heritage Site. Flat roof installations and ground-mounted systems have additional restrictions. If in doubt, your local planning authority can provide a lawful development certificate for a small fee (~£100–£200).

G98 is the simplified notification process for solar systems up to 3.68 kW per phase (single-phase household limit of 3.68 kW). Your installer simply notifies the Distribution Network Operator (DNO) within 28 days of commissioning — no prior approval required. G99 is required for systems above 3.68 kW per phase or where the DNO needs to assess grid impact. G99 requires pre-application approval, which adds 4–12 weeks and typically £500–£2,500 in fees. Most domestic systems (up to 3.68 kWp) use G98; systems above this — increasingly common with battery storage — may need G99.

The Labour government's Clean Energy Superpower Mission targets 50 GW of solar capacity by 2030, up from approximately 17 GW in early 2026. For homeowners, this creates urgency: as the grid becomes more solar-heavy, the value of battery storage increases (self-consumption economics improve) and time-of-use tariffs become more favourable for solar owners. The government's investment in grid infrastructure and the continuation of the Warm Homes Local Grant are also direct results of this policy commitment.

The Microgeneration Certification Scheme (MCS) is the UK's quality assurance standard for small-scale renewable energy installations. MCS certification is mandatory for: (1) accessing the Smart Export Guarantee; (2) claiming VAT relief at 0%; (3) eligibility for the Warm Homes Local Grant solar funding; (4) accessing the MCS Installation Protection Guarantee (warranty backstop). MCS also regulates installer conduct — you can raise complaints through the MCS Consumer Code if an installer fails to meet standards. Never use an installer who is not MCS-certified.

Evidence is increasingly positive. A 2024 Rightmove/Solar Energy UK analysis found properties with solar panels sold for 0.9–4.1% more than equivalent properties without solar, depending on region and system size. In the South East, a 4 kWp system with MCS certification and a valid EPC improvement was associated with an average £8,000–£12,000 uplift. The effect is most pronounced when the EPC rating improves from C to B or D to C, as mortgage lenders increasingly offer "green mortgage" discounts for higher-rated properties.

Since April 2022, all residential solar panel installations are zero-rated for VAT under the Energy Saving Materials relief. This applies to: solar panels, inverters, battery storage systems, mounting systems, and associated electrical equipment installed as part of a solar system. On a £8,000 quote, this saves you £1,333 compared to paying standard 20% VAT. Your installer should apply this automatically — if a quote includes VAT, ask why and request it be removed. Note: commercial and mixed-use properties may be subject to different rules.