Should I charge my batteries overnight in Summer?

daksolaruser

Officer_Dibble said:

Well ditch Flux for starters, I can't believe it's the best tariff for anyone at current prices. Charge overnight at 6.7p/kWh and export at 16.5p/kWh with EON and the decision to charge at night is clear-cut.

I'm with EON but my overnight rate is almost 10p - they didn't offer me a better tariff than that... There used to be dozens to choose from but not I seem to get 'this one or that one' only.

daksolaruser

charles_b_2 said:

I'm charging overnight at 8p.  If i take a chance on the weather it would be charged via solar by mid morning, but on days like today, sadly its not. But the upside is I i export at 15p. So, subtract the import cost and i still make around 6p (more or less if you take account of conversion losses)

It is as straightforward as that isn't it? My brain keeps telling me that 'free' charging during the day must be better... lol

charles_b_2

daksolaruser said:

charles_b_2 said:

I'm charging overnight at 8p.  If i take a chance on the weather it would be charged via solar by mid morning, but on days like today, sadly its not. But the upside is I i export at 15p. So, subtract the import cost and i still make around 6p (more or less if you take account of conversion losses)

It is as straightforward as that isn't it? My brain keeps telling me that 'free' charging during the day must be better... lol

It could be!  Really depends on your point of view.  I prefer the surety of having my battery ready to take on the load for the full day and only get trickle charged if cloudy/rainy, whilst if it's sunny, the whole of the solar is exported (minus the house draw).  off my 6.75kWp array I was getting 30-40 KW a day, the vast majority exported.  If the battery needed charging, then 9Kw would be used to charge it, losing 15p of income
Simple example:
Charge overnight: 9Kw * .0.08 = 0.72.  Export 30Kw *0.15 = £4.50 : NET +£3.78
Do not charge overnight = 0.00 Export 21Kw * 0.15 = £3.15: NET +£3.15
The difference covers the standing charge!

Actually, if I don't charge, then the battery is 'empty' for about 3 hours, at approx. 300W base load, so ~1Kw imported, so the net is actually £3.07

Qyburn

daksolaruser said:

I'm with EON but my overnight rate is almost 10p - they didn't offer me a better tariff than that... There used to be dozens to choose from but not I seem to get 'this one or that one' only.

Eon say that you'd be eligible for their EV tariff, solar/storage systems are specifically mentioned.

ed110220

I'm charging up on Octopus Go for 8.55p/kWh each night still. I was thinking of switching back to Flux for the summer but not convinced it's worth it.