How do I export solar electricity back to the grid in the UK?

Exporting solar electricity to the grid happens automatically — when your panels produce more than your home is using, the surplus flows back into the street wires. You don't need to do anything to make this happen technically. But to get paid for it, you need two things: a smart meter (so the precise amount you export can be measured in 30-minute intervals) and a Smart Export Guarantee (SEG) agreement with an energy supplier. To get set up: contact your energy supplier to arrange a smart meter if you don't have one; then find the best SEG rate among available suppliers at the time; sign up — you'll receive payments on your electricity bill or separately. SEG rates vary from around 4p to 20p+ per kWh. You can export and get paid from the day your MCS-certified installation is registered — it doesn't matter if you're with the same supplier for import and export.