EricMark
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Changing because the supplier I have has dragged their feet for a year, and still no payment for export. But I have been charging batteries overnight, then they have only discharged to 80% and then latter I have been exporting for no payment.
Working out tomorrow's weather is not really what I am good at. And there is a second dip in state of charge in the evening, where the batteries reach the 10% limit set, most days. And some days the battery never fully charges from solar.
So tariffs, it seems the very cheap overnight tariff also does not pay much for export, take Octopus as an example, their "Go" rate only pays 8p per kWh for solar export, but the "Flux" pays 13.9p until 4 pm, then 27.73p until 7 pm the overnight tariff for export I will never have power to export, so not interested in.
With a 3.2 kWh battery, the BG EV rate worked out well, However the battery would only charge at 2 kW and discharge at 3 kW so was seeing import/export when it should not really happen, so doubled up, 6.4 kWh, now discharge 5 kW (inverter limit) import at 4 kW, so other than a shower, don't use grip power in the day.
If I could set battery to charge only to 50% with off-peak, then maybe I could configure it better, but seems time is only control, so set only enough time to charge to 50%, but there was 60% left, and still fully charged.
Once one signs up to a tariff, can be stuck for a year, but is the 1p here and there really worth chasing? Why Octopus, simple, the solar panel installer will do all the work to ensure I get payment for export. Having tried for a year with British Gas, don't want that again. I looked back, to see when the batteries had run out between 4 pm and 7 pm, just twice, so unlikely to pay the 36.06p per kWh very often. And the 25.76p is cheaper than ever paid to British Gas.
My solar logs how much each day, but not how much before 5 am and how much after, the graph one can hover mouse to see what used at that time (kW) but not up to that time (kWh) working out area under the graph is too much like hard work.
So in the main guess work, may as well be blindfolded and stick pins in the page. Not helped as need post code entering before you can see the rates on offer.
