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“We did send free electricity to the grid as we’ve not sorted tariffs yet.”
Photo Credit: iStock
A U.K. homeowner with a new solar setup said a 6.2-kilowatt array and 9-kilowatt battery covered the home’s needs for essentially a full day without meaningful grid use.
But the export side was not fully sorted yet, so any surplus electricity still had to go back to the grid without payment.
In a Reddit post in r/SolarUK, the homeowner said the setup, which includes a 6.2kW PV array, 8kW Sig inverter, and 9kW Sig battery, delivered enough power on its first fully sunny day to make grid use negligible over 24 hours. Taking advantage of the excess generation, they wrote that they ran the washing machine “when the battery hit 100%.”
“We did send free electricity to the grid as we’ve not sorted tariffs yet (waiting on certificates etc),” the poster explained, referring to the U.K.’s Smart Export Guarantee (SEG) tariff that pays residents for the renewable electricity they send back to the grid. The home could already reduce imported electricity, but payments for exported power had not begun.
Replies centered on tariff choices and the money involved once export payments are active. One commenter advised, “Go for import and agile for export is my recommendation until they up the export on the fixed export.” 
“22 kwh in one day from 6.2kw is great, i have 4kw and when i get 15 on a sunny day,” one commenter applauded.
“I’d definitely smash more battery into that system,” one person suggested. “The key is how much you can export in a narrow window of peak pricing either via axle or agile export – and whether it’s worth it.”
Solar can cut home energy costs, especially when a battery lets homeowners use more of their own electricity instead of buying it later from the grid. Readers who want to compare pricing and projected savings can use EasyHome‘s free explorer tool to see options from vetted installers in their area.
With energy prices through the roof, there’s never been a better time to go solar — and EasyHome can help you find the best prices from the best installers in your area.
EasyHome takes the guesswork and headaches out of energy upgrades by showing you estimated savings from a network of vetted local partners. To get started, just enter your ZIP and share a few details about your home — seeing your estimate is really that easy.
One person in the thread said the original poster’s household would probably need both an export MPAN, an administrative reference for a home’s exported electricity, and a G99 certificate, which grants permission to export electricity from a home to the grid, before they could begin exporting electricity and getting paid for it.
A system can start producing exportable surplus right away, but the value of that electricity can vary widely by location and plan, and installation day is not always the same as payment day. 
One commenter added, “Last month my average export price was 17.66p kWh,” which converts to $0.24, underscoring that delayed export setup can have a real cost.
Another commenter in Northern Ireland wrote, “Cries in Northern Ireland where we get 9.7p for export or something,” which converts to $0.13.
One commenter in the thread shared a possible shortcut for people dealing with SPEN. After the MCS paperwork and G99 connection agreement are in place, homeowners can contact the network operator to request an MPAN assignment and ask to be copied on the response. That can help new solar owners get the number as soon as it is issued instead of waiting for it to filter through office administration.
If you are considering a setup like this, EasyHome‘s free explorer tool is useful because it lets you compare vetted local installers, compare competitive bids, and review savings without sharing your contact information unless you choose to move forward. It can also help you explore backup battery storage, and pairing solar with a battery can maximize savings while keeping your home powered by solar when the grid goes down.
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© 2025 THE COOL DOWN COMPANY. All Rights Reserved. Do not sell or share my personal information. Reach us at hello@thecooldown.com.

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