Pete UK
Member
Yep - agree winter is rubbish compared to summer. The point I was trying to make was that even, say a “4kW” a day generated is 4kW added to the 38kW (/whatever battery size you have) downloaded overnight from grid in the battery I (/you/anyone) wouldn’t have to buy at 42p peak. And you’d use at least 4kW in winter from 0530 till useful generation starts, So that’s £50 a month saved; If it were only an average of a 4kW trickle per day.If that's from my image above? then its from 48 panels ... and my best ever winter day, "useful generation" for only around 4 hours in the middle of the day, and breaks down roughly like this:
For context: I have 48 panels, and average use is ~50kWh a day
April 1782 kWh : 5 "low days" 25-ish kWh, most are around 60kWh, and 7 are 80-ish kWh
(June, July, August around 2,200 kWh)
January 388 kWh : 14 "low days" < 3kWh, 5 days 5-ish kWh, 7 days 10-20kWh, 5 days > 20Kwh
December 257 kWh - 12 "low days" < 3kWh, 14 days 6-10 kWh, 5 days 15-ish kWh
Someone with, say, 16 panels might only get 1/3rd of that, dunno how much is needed before the systems will actually start?
So apart from the occasional "perfect" winter day, in Winter the norm is "rubbish" - I would characterise whatever I get as a bonus, rather than anything that actually contributes to my consumption. Just don't want anyone to assume that the 4 winter months contribute anything useful - particularly as that occurs at a time of greater electricity use (even if only more lighting for the long winter nights)
I’m not sure of your usage profile or situation but;
On the excellent winter days where your getting 10-20kW or 20kW that’s £4.20-£8.40 or £8.40 per day, so that’s 7 days saving you (using 15 average) £42 total and 5 days saving you a total of £42. Assuming you can use/store that extra.
In other situations, A 4kW trickle generated could stretch the time before you start using peak by 8 hours at 500w background or 4 hours at 1kW background drain.
Plus (or minus ) probably out of the whole 50kW you’d use on a winters day maybe 10-12kW (in our case) of that might be going in a car which would be off peak already.
I’m just rambling really but it seems that with a high useage one just has to accept the fact that in winter you’re never going to have a big enough battery (unless you go mad on kit, but you still need the time/ grid power/ approval/ ability to charge it in the off peak window) and are going to have to pay for some peak price kW’s. But that’s ok. Every little helps though and all adds up.