Case Study 8: Mr and Mrs Spalding 


Mr and Mrs Spalding have a larger than average 7.2kW solar panel array across 21 panels, together with a 9.7kW battery system.

Their panels arrived in December 2020, although the battery wasn't installed until March 2022. There are four people living in their house and they use a lot of electricity because they also have two electric cars. The whole system cost £13,500 in total and they use SolarEdge for their data. 

Mrs Spalding says that they just missed out on receiving FiT payments as this scheme closed to new applicants in March 2020. However, they do receive 7p per kW exported to the Grid. This is known as the Smart Export Guarantee (SEG) scheme. SEG launched in 2020 and is a government-backed initiative which requires some electricity providers to pay households for generating low carbon electricity exported back to the grid. You can be a SEG generator if you have solar panels, a wind turbine, or hydro power. Additionally, Mr and Mrs Spalding also take advantage of a cheaper overnight rate on their electricity from their provider, Octopus, and between 12.30am and 4.30am, their electricity costs just 7p per kW.  


So far this year (as of end April 2022) they have consumed 2.72mWh, imported 1.26mWh, used 1.46mWh of solar generation themselves and exported 0.3mWh back to the grid. They do not have a complete year's worth of data as their Smart Meter was only installed midyear last year. However, Mrs Spalding is able to determine that last year they produced 7,550kWh in total. She tells us that their battery system in particular works very well for them because they will charge their cars overnight:

"Our first electric car came in September 2020. This was upgraded in December 2021 and then we bought a second electric car in April 2022. Last night we plugged in the second car, used the cheap electric rate between 12.30am and 4.30am and only paid 80p or 16kW at 5p per kWh to top it up!"

Due to their overnight rate, they do take their Everhot off ECO at 4am to take advantage of the cheaper electricity to bring it back to full power before their higher rate kicks in during the day. 

"We invited three national companies and two local companies to quote, and for each person who visited us, we learnt something new. Because of our two cars, and the Everhot, we are fairly high users of electric. But our roof is south/southwest facing with no shade at all and we were told that it would be better to get more panels at once than to add to them at a later date. Ours is the biggest array you can have without a three-phase electric supply. And just to say we did have to pay Scottish Power £250 for permission but we didn't need actual planning permission."