Outgoing Octopus

[Stinsy]

Are you big export people on 3-phase? or just going dawn to dusk?
A smallish array, a 3.6kW inverter and G98 approval cramps one's style a bit, especially when on top of that (I suspect) my export is being throttled back by the grid voltage...
A

3.6kW inverter here. I export at full whack from 0300-0600, 0900-1800, and 2100-0000. The rest of the time I game additional cheap slots and charge from the grid.

How long is the cable from your CU to inverter? And what size is it?

I’m similar to stinsy with a 5 kw inverter give or take a few mins either side of his times

The benefit of a 5kW inverter over and above a 3.6kW one is more than you might assume at first sight. The raw inverter capacity is c. 39% larger. However once you account for the house baseload (500W for the sake of example) then the inverters allow you to export 3.1kW and 4.5kW respectively. This is a 77% difference.

[AE-NMidlands]

Are you big export people on 3-phase? or just going dawn to dusk?
A smallish array, a 3.6kW inverter and G98 approval cramps one's style a bit, especially when on top of that (I suspect) my export is being throttled back by the grid voltage...
A

What has been your best export day this Spring? It's still a learning curve as we've not been exporting for a full year.

Ww generally export 07.30 to 17.00 @ 100% then down to 40% 17.00 to 23.30

Export PB on 2nd April 3.6kW nominal Hybrid, first £10 day. I would like to crack 80kWh this year. Might manage that in the fortnight away coming up.

I'm on Flux so I limit import to 0200 to 0500, and I try to match the amount (target %) to the following day's sun. Export during the evening peak (lower limit 15% to keep the house going until 2 a.m.) then let it top up to 30% if needed at 2am, watch the solar refill it during the day, hopefully getting to 100% by 1600 when I have a 3.6kW export session, the sun supplying some or all of it initially and the battery taking over.


the above shows my last import, the W-facing array puts a bit into the battery after 7pm now. I could top up to 100% at 2 a.m. but that is at 17 p/unit and my daytime export rate is ony 10.5! I reckoned there was no point filling the battery up with power that was more expensive than it would sell at. Below is a typical day at the moment,with lots of washing being done. sometimes the sun is enough to start exporting before 4pm, not since I limited my 2am charge target though:




Best recent export was 10.9 kWh..., best financial day this year so far was 2/4 when we imported 0.5kWh, exported 9.1 peak units and had a bill of -£1.79 net of the 66p standing charge. p.s. Generated 15.1 kWh that day...

[John_S]

I have 2.1kWp solar with original SMA inverter, 10kWh of Pylons and a 3.6kW Solis inverter.

My current strategy is to charge the batteries to 100% between midnight and 0530 and to export from 7am to midnight except for 1800 to 2000 when dinner is cooked. I set the export current to achieve this.

The extra half hour between 2330 and midnight allows some over shoot time if house loads are lower than expected in the evening.

Solar is all exported except when house loads are above the export that I have set. Times and rates get adjusted for saving sessions, power hour and cheap slots for car charging. Occasionally I forget to adjust back and mess things up a bit.

I don't usually charge the car outside 2330 to 0530 unless I have a long drive the next day.

Cheap slots seem harder to obtain in London, or I have not learnt how to game them better.

[AE-NMidlands]

I have 2.1kWp solar with original SMA inverter, 10kWh of Pylons and a 3.6kW Solis inverter.

My current strategy is to charge the batteries to 100% between midnight and 0530 and to export from 7am to midnight except for 1800 to 2000 when dinner is cooked. I set the export current to achieve this.

The extra half hour between 2330 and midnight allows some over shoot time if house loads are lower than expected in the evening.

Solar is all exported except when house loads are above the export that I have set. Times and rates get adjusted for saving sessions, power hour and cheap slots for car charging. Occasionally I forget to adjust back and mess things up a bit.

I don't usually charge the car outside 2330 to 0530 unless I have a long drive the next day.

Cheap slots seem harder to obtain in London, or I have not learnt how to game them better.

that might work because Octopus give very cheap electricity to BEV owners... What is your cheap rate? (to compare with my 17.1p)

[Stinsy]

that might work because Octopus give very cheap electricity to BEV owners... What is your cheap rate? (to compare with my 17.1p)

17.1p

Even vanilla Go is 9p. Pretty much everyone on here is on Intelligent at 7p.

[Yuff]

3.6kW inverter here. I export at full whack from 0300-0600, 0900-1800, and 2100-0000. The rest of the time I game additional cheap slots and charge from the grid.

How long is the cable from your CU to inverter? And what size is it?

I’m similar to stinsy with a 5 kw inverter give or take a few mins either side of his times

The benefit of a 5kW inverter over and above a 3.6kW one is more than you might assume at first sight. The raw inverter capacity is c. 39% larger. However once you account for the house baseload (500W for the sake of example) then the inverters allow you to export 3.1kW and 4.5kW respectively. This is a 77% difference.

The 5kw inverter makes a huge difference to our export numbers which means I can’t quite match your export hours. Yesterday was a very good day and I managed to get from 9.45am to 5.30pm before our batteries ran out.
Also managed a PB for export at just under 51 kWh, which is unheard of in the first week of April

[Richard77]

So the name of the game is export as much as you can no matter what at 15p, as long as you can import at 7p?

Fill batteries during the night... Export as soon as. Hope PV covers usage during the day (any excess exports too). When batteries depleted or as low as you want them to go, game a slot and start filling batteries again?

I think when I get my batteries installed, I will try keep the soc enough to cover the evening usage when the pv stops generating until 23:30. I won't have to try game slots then. Ideally want it so don't have to think about it and mess about with all the gaming shenanigans (plugging car in, etc).

[Richard77]

Quick query...

Can the batteries power the house at the same time as exporting back to the grid?

Obviously they can... As that is what the PV does... Apologies for the stupidity!

[AE-NMidlands]

Quick query...

Can the batteries power the house at the same time as exporting back to the grid?

Obviously they can... As that is what the PV does... Apologies for the stupidity!

actually they can only send to the grid what the house isn't calling for. Hence the hole in my 3.6kW export (red) in the second graph in post 242 at about 1745 when we put the kettle on (green load). I wish a bigger inverter than my 3.6kW had been available, 5kW at least!
My next system will be more batteries and a second bigger inverter to power the house while the exisiting one just dumps to the grid with no interruptions.

[Richard77]

Quick query...

Can the batteries power the house at the same time as exporting back to the grid?

Obviously they can... As that is what the PV does... Apologies for the stupidity!

actually they can only send to the grid what the house isn't calling for. Hence the hole in my 3.6kW export (red) in the second graph in post 242 at about 1745 when we put the kettle on (green load). I wish a bigger inverter than my 3.6kW had been available, 5kW at least!
My next system will be more batteries and a second bigger inverter to power the house while the exisiting one just dumps to the grid with no interruptions.

I thought that the battery would act the same as the PV as both DC input into the inverter.

PV (DC) -> inverter -> powers the house and excess is exported.
Or...
Battery (DC) -> inverter -> powers the house and excess is exported.