Ofgem announces the January cap in late November. The suppliers have already shown their homework: EDF forecasts £1,932, E.ON Next £1,941, British Gas £1,970. Against today's £1,723, that's a 12–14% rise, scheduled for the months when your heating is on and your panels are at their least impressive. Naturally.
The winter solar reality, stated plainly
A UK plug-in kit produces roughly a quarter of its annual output between October and February. Short days, low sun, Welsh cloud doing what Welsh cloud does. Anyone who sold you winter solar as a heating solution was lying to you; we didn't, and won't start now.
Why the forecasts still matter to solar owners
Because payback maths runs on the price of the electricity you don't buy, and that price keeps going one way. At the October rate of 26.32p/kWh, an 800W kit's annual output is worth roughly £130–£175 in avoided imports. If January lands where the forecasts point, the per-kWh value rises again — every winter morning kettle and laptop running on panel output displaces the most expensive electricity in two years.
The kit doesn't change. The grid gets more expensive around it. Our payback rerun from the October cap becomes conservative if the forecasts hold — a sentence we also wrote in August, and were right.
What we'd actually do before January
Two things, neither of which is panic-buying panels in November. First: if you've been weighing a kit, the maths says the decision doesn't improve by waiting for January's announcement — winter installs catch the spring generation ramp from day one. Second, and bigger: your tariff matters more than your panels this winter. A household that can shift usage typically saves more on a smart tariff than a plug-in kit generates — and they stack. Octopus Agile plus solar remains the best combination in the UK; switching via our referral link adds £50 credit on each side, which in January-rate terms is most of a winter month's electricity.
We'll report the actual number when Ofgem publishes it. The forecasts have been warned.
