Can you store cheap rate leccy ?

[DSLiverpool]

So we get the Octopus 5p rate and use it as much as possible but it got me wondering can we pull cheap power off and store it anywhere to push into the car another time?

[coetzeeh]

I think the 5p rates will be history soon given the doubling of commodity costs in 2021.

[sjg]

Yes, lots of storage batteries - usually meant to store daytime solar for evening, but nothing to stop you filling at cheap rate.

Expensive though and I worked out our payback time as being over 8 years even assuming the cheap rates today stay as they are.

[phil4]

I think EVMan on your tube does just that, but on Octopus Agile, so buying at the cheapest rate overnight and selling back at the more expensive points.

[dmsims]

phil4 said:

I think EVMan on your tube does just that, but on Octopus Agile, so buying at the cheapest rate overnight and selling back at the more expensive points.

Yeah and he's a bit of a moron

Have you actually looked at Agile rates since about December 2020 ?

[hyphen]

As said, they do storage batteries. But you will need to calculate the payback period to see if its worthwhile.

[gmaz]

I store 5p/kWh Octopus Go leccy in my GivEnergy 8.2kWh battery. In summer, charge it to 50% and that's enough until the solar panels top it up. In winter I'll probably charge it to 100%.

[craigjm]

I’ve just come back from a couple of years in South Africa where being thrown off the grid so they can balance demand is a regular occurance. Batteries and n inverter are standard. You can buy really big ones the size of washing machines. Costly though so takes many years to get your investment back if you go that big

[hyphen]

gmaz said:

I store 5p/kWh Octopus Go leccy in my GivEnergy 8.2kWh battery. In summer, charge it to 50% and that's enough until the solar panels top it up. In winter I'll probably charge it to 100%.

Payback period?
gross Savings?

[dmsims]

hyphen said:

gmaz said:

I store 5p/kWh Octopus Go leccy in my GivEnergy 8.2kWh battery. In summer, charge it to 50% and that's enough until the solar panels top it up. In winter I'll probably charge it to 100%.

Payback period?
gross Savings?

Payback around 27 years, if it's still working!

[gmaz]

hyphen said:

Payback period?
gross Savings?

No idea. I mainly got it for storing excess solar.

[LargeRed]

5p/Kw and lots and lots of batteries.

it is not easy or economical to store energy.

Not like buying cheap fuel for your vehicle and having a handy spare in the boot.

[foggy]

Another car?… Ioniq 5 can charge other vehicles and has mains output. Think of it as a mobile battery…

[Lily the Pink]

Use it to power a pump to push water up to a tank in your loft. Then let the water down to power a turbine when you need the leccy. Doubtless totally uneconomic, but a fun project.

[phil4]

dmsims said:

Yeah and he's a bit of a moron

Have you actually looked at Agile rates since about December 2020 ?

I think that's a bit harsh... his vid was a while back. And you're right, Go is a much better idea at the moment. If only Octopus hadn't fitted a dud smart meter, that'd be what I'd be on - I'm not bitter.

[Desiderata]

I was looking at something along these lines here in Scotland where most of the public EV charging is free. Charge the car up while at work then bring it home and drop 80% of the charge into the domestic supply.
It doesn't really make financial sense for me at the moment as I don't need a new car yet, but it might do in some circumstances.

Edited by Desiderata on Monday 16th August 08:54

[dapprman]

I do just this - my solar install was back at the start of February, so from the start (until ~May) I was putting power in to the battery from the grid during my night rate period (00:00-07:00 for me). Was adjusting the schedule almost daily though I really need to just stick with the one going forwards (once winter sets in) when I'm not charging the car. Note plug your EV in and watch the battery drain in half an hour to a couple of hours depending on battery size.

Even during the summer I've topped the battery up at night a few times - a few times due to it being a poor summer and on occasions i was just not generating power, and on the other occasions because I was charging the car and so would need to refill the battery, i.e. 00:30-02:30 charge car, 03:30-04:30 top up battery to have enough power to comfortably get through to max sun the next day.

BTW as others have said - the batteries themselves are expensive and rather than prices staying static as new tech comes in (i.e. larger capacity), instead prices seem to rise with the previous models being kept around. Mine is 10kW based on two 5kW packs.

[oop north]

Desiderata said:

I was looking at something along these lines here in Scotland where most of the public EV charging is free. Charge the car up while at work then bring it home and drop 80% of the charge into the domestic supply.
It doesn't really make financial sense for me at the moment as I don't need a new car yet, but it might do in some circumstances.

Edited by Desiderata on Monday 16th August 08:54

I think you would need to have a different sort of charger which costs several £k (or a Kia EV6 / Hyundai Ioniq5 with the vehicle to load function) to allow vehicle to home charging - there is a current trial with Nissan Leafs exploring this (or maybe vehicle to grid) but currently not possible.

[ZesPak]

foggy said:

Another car?… Ioniq 5 can charge other vehicles and has mains output. Think of it as a mobile battery…

V2L/V2G should become more common in the coming years.

[steve-V8s]

Just out of interest what is the efficiency of storing off peak in batteries. Presumably when you charge not all of the power actually ends up in the battery and again when you draw from the battery there most be losses.

I guess if you are charging from solar it is not an issue but if you are charging from the grid off peak and using later the system losses must have an effect on the cost calculation.