What Happens to Excess Solar Electricity?
When your solar panels generate more electricity than your home is using, the surplus automatically flows back into the national grid. You cannot store it unless you have a battery. But you can get paid for it.
Excess solar electricity automatically flows to the grid. You get paid for it through the Smart Export Guarantee, but the real value is in using your solar power yourself rather than exporting it.
How Solar Export Works
The process is automatic. Your solar inverter converts DC power from the panels into AC power for your home. If generation exceeds consumption at any moment, the excess flows through your meter and into the grid. Your neighbours effectively use your surplus electricity.
A smart meter records both what you import from the grid and what you export. This is how your energy supplier knows how much to pay you.
The Smart Export Guarantee (SEG)
Since January 2020, the Smart Export Guarantee has replaced the old Feed-in Tariff (FIT) for new installations. Key facts:
- Who qualifies: Any home with solar panels up to 5MW capacity and a smart meter
- What it pays: Rates vary by supplier, typically 3-15p per kWh exported (as of 2026)
- Who pays: Your energy supplier, under the SEG obligation. All licensed suppliers with 150,000+ customers must offer a SEG tariff
- How to sign up: Contact your energy supplier or shop around — you do not have to export with the same company you buy from
At current SEG rates, a typical 4kWp system in Milton Keynes exporting around 1,500-2,000 kWh per year earns roughly £75-200 per year from exports alone.
Self-Consumption vs Export: Where the Real Value Is
Exporting is worth less than using the electricity yourself. Here is the maths:
- Self-consumption value: Every kWh you use from your panels saves you 28p+ (the cost of buying from the grid)
- Export value: Every kWh you export earns you 3-15p (the SEG rate)
That is why maximising self-consumption is the priority. Running high-energy appliances (washing machine, dishwasher, EV charger) during daylight hours captures more of your free solar electricity. Adding a battery lets you store daytime surplus for evening use.
Want to maximise your solar savings? A battery stores your surplus for evening use.
Get Free QuoteEvery kWh you use yourself saves 28p. Every kWh you export earns 3-15p. Self-consumption is worth roughly 2-4x more than exporting. A battery or smart usage habits make a real difference.
Do You Need a Smart Meter?
Yes, for the SEG. Without a smart meter, your supplier cannot measure how much you export and therefore cannot pay you. If you do not have one yet, contact your supplier to arrange installation — it is free.
If you have an older generation meter, it may actually run backwards when you export (benefiting you), but this is not guaranteed and suppliers are phasing out these meters.
Can You Sell Solar Power Directly?
Not directly to your neighbours, no. In the UK, selling electricity requires a supply licence. However, peer-to-peer energy trading platforms are emerging, and some commercial solar installations use Power Purchase Agreements (PPAs) to sell directly to businesses on the same site.
For residential solar, the SEG is currently the only practical route for monetising surplus electricity.
Ready to start generating your own electricity and earning from exports?
Get in TouchPeer-to-peer energy trading platforms are emerging in the UK. In the future, you may be able to sell surplus solar directly to neighbours. For now, the SEG is the only option.
Frequently Asked Questions
How much can I earn from solar export?
A typical 4kWp system exports around 1,500-2,000 kWh per year. At current SEG rates (3-15p/kWh), that is £75-200 per year. The exact amount depends on your export rate, system size, and how much electricity you use during the day.
Does the grid pay for all my excess solar?
Your energy supplier pays for exported electricity under the SEG, not the grid operator. You must sign up to a SEG tariff to receive payments. Without signing up, your surplus goes to the grid unpaid.
Is it better to get a battery or export to the grid?
A battery is almost always the better financial choice. Storing electricity for your own evening use saves you 28p+/kWh (the import rate), compared to earning 3-15p/kWh from export. The payback on a battery is typically 7-10 years.
What is the difference between FIT and SEG?
The Feed-in Tariff (FIT) closed to new applicants in March 2019. It paid for all generation plus exports at generous fixed rates. The Smart Export Guarantee (SEG) only pays for exported electricity at market-led rates. Existing FIT recipients keep their contracts for the full 20-year term.