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Hello
Posted: Wed Jun 07, 2023 4:50 pm
by Letthesunshine
I'm new to this forum
My annual PV generation is 3890kWh
I use 936kWh to heat water via Solarboost
I can provide more information if you let me know what you want.
There seems to be a lot of knowledge on the forum so I wonder if someone can help.
My problem is that even at night, when my electricity use is minimal and my battery is nearly fully charged I am still importing. It is less that 0.1kW but over the year it is costing me several hundred pounds.
My Powervault app doesn't register any import, but Octopus does.
Is this a particular issue with my Powervault system or do I need to live with it?
Powervault say this is normal.
I'd welcome your advice.
Andy
Re: Hello
Posted: Wed Jun 07, 2023 5:15 pm
by Joeboy
Letthesunshine wrote: ↑Wed Jun 07, 2023 4:50 pm
I'm new to this forum
My annual PV generation is 3890kWh
I use 936kWh to heat water via Solarboost
I can provide more information if you let me know what you want.
There seems to be a lot of knowledge on the forum so I wonder if someone can help.
My problem is that even at night, when my electricity use is minimal and my battery is nearly fully charged I am still importing. It is less that 0.1kW but over the year it is costing me several hundred pounds.
My Powervault app doesn't register any import, but Octopus does.
Is this a particular issue with my Powervault system or do I need to live with it?
Powervault say this is normal.
I'd welcome your advice.
Andy
Welcome Andy, most inverters will pull a little from the grid to run. A quick check puts you at max 876kWh pa on 0.1kW background load. Which tarrif are you on?
I am currently 0.5kWh to 0.6kWh per day or 200kWh pa average for reference (that's optimal days). Hopefully a powerwall owner will be along soon
Re: Hello
Posted: Wed Jun 07, 2023 5:21 pm
by Letthesunshine
Hi
I am on Octopus Cosy
I import between 0.03 and 0.07kW all day
Andy
Re: Hello
Posted: Wed Jun 07, 2023 5:28 pm
by Letthesunshine
Sorry I typed Powervault but it should have been Powerwall
Re: Hello
Posted: Wed Jun 07, 2023 5:40 pm
by Joeboy
Letthesunshine wrote: ↑Wed Jun 07, 2023 5:28 pm
Sorry I typed Powervault but it should have been Powerwall
There are a few powerwall owners here. By dint of being grid connected there's really no way to null it out (I think).
Re: Hello
Posted: Wed Jun 07, 2023 7:57 pm
by nowty
Welcome Letthesunshine,
You may have one of the dodgy smart meters which don't like Powerwalls, if so Octopus should swap it out.
https://octopus.energy/blog/perils-work ... nnovators/
"Our conclusion is that both devices fully comply withtheir respective standards,however there is an incompatibility between them which is only detectable under the rare conditions when the L+G meter doesn’t have a load and is exposed to the noise from the Powerwall . We have concluded that it’s just the one L+G meter model and so far only with the Tesla Powerwall. We’re yet to find any other battery system experience this issue (we’ve tested one other manufacturer in the lab too) although this may be because Tesla is simply the most popular and well established nor is there an issue with any other smart meters (we’ve tested 6 others in the lab) or other L+G models.
Now we’ve solved the riddle we’re changing Octopus Energy customers that have a Tesla Powerwall and the L+G smart meter by changing their L+G meter for an equivalent L+G model.
We’re keen to stress this issue is affecting a very small number of customers and is only related to the combination of the Tesla Powerwall and the specific L+G smart meter model but unfortunately there’s been a fair amount of public discussion more generally referring to all home battery systems and all SMETS2 smart meters so we’re sharing our investigation in full and what action we’re taking.
If you think you’re affected by this feel free to contact me directly via agile@octopus.energy or find me on Twitter as @agile_phil and we’ll take a look at your Octopus account (we need to look at the half hour data over a few weeks) and investigate and resolve it if you are affected."
Re: Hello
Posted: Thu Jun 08, 2023 10:32 am
by Mr Gus
That is handy info for future trawling.. nice one nowty.
OP might assist others if you edit the post where the brand error occurred, it also sounds like Octopus / other suppliers ought get this information out there for any install works (ie alleviate the problem prior to meter change) drawing attention to possible outcomes (powerwall Y/N) ..as simple as that.
Re: Hello
Posted: Thu Jun 08, 2023 11:10 am
by nowty
Also some inverters like my SMA Sunny Island has a facility to set a plus or minus offset in watts to correct any errors.
Its very difficult for inverters to measure near zero current. I have to set an offset of around 10W (export to grid) in order for my battery inverter to read zero import/export.
The same setup with my older E7 meter and I could import about 20W before the meter started clocking up.
Re: Hello
Posted: Thu Jun 08, 2023 2:01 pm
by Thebeeman
I'm on Pylontech and a Lux inverter and my daily import at present is 0.4-0.6 Kwh per day. It seems to be a lag in the inverter shifting between battery, solar and grid. I've decided not to lose any sleep though.
Re: Hello
Posted: Thu Jun 08, 2023 3:17 pm
by openspaceman
Thebeeman wrote: ↑Thu Jun 08, 2023 2:01 pm
I'm on Pylontech and a Lux inverter and my daily import at present is 0.4-0.6 Kwh per day. It seems to be a lag in the inverter shifting between battery, solar and grid. I've decided not to lose any sleep though.
Same here, I'll not worry until it reaches the same cost as the standing charge.