To force discharge, or not to force discharge, that is the question:

MrMessy

Whether 'tis good for the inverter to suffer
The charging and exporting of meager fortune,
Or to hold SoC against a sea of diminishing returns
And by self consuming end them.

For the last few years, my strategy with Octopus has been simple. Charge fully overnight (and any smart charging slots), export all solar in the summer, and force discharge any excess in the evening.
Now, we're entering new territory, with significantly reduced returns on arbitrage, I'm not sure that the additional wear and tear on inverter/batteries is worth the small (approx 3p/kWh after losses) return.
Additionally, for the first time, it's looking like Flux may be viable for 4-6 months, whereas previously it had been extremely marginal for me, so not worth the risk.

What are you doing now export rates are dropping?

KristianS

MrMessy Yes, I read the email from Octopus with a little dismay too. But it was always coming.
For purely financial reasons, even at the old rate, it was fairly mediocre as a means of return.... but it did make sense. Going forward..... very much less so.
However, for me, just for the record, my priority is not just personal financial gain. I genuinely want to put less impact on the grid, and now that I have a home battery, I like to contribute my little bit in reducing the Peak 16:30 - 19:00 demand on the gird so we burn less gas to meet the demand. I realise my personal contribution is tiny, but if there were a million home batteries like mine all contributing 5kW then that would be 5GW, which would just about remove the peak entirely.
Also.... as you know all too well, GivEnergy and thier SoC shenanigans still requires an Empty to Full to Empty routine on a reasonably regular basis, otherwise the system has zero idea of what the SoC is has not gone away either.
I see some folks on here charge discharge two or even three times a day.... I don't see the point in stressing the system like that, but a near once per day or five times a week equivalent as a compromise.
By the time I get to the end of my warranty period in 2035, battery technology will have moved on so much, it might be time to swap them out anyways..... even if they are only giving me 60-70% of the performance they do today.
By then, home batteries will be some super-special sodium variant at ~ £40 / kWh, and I can happily buy a system that will cost me under £3k and will last over a week in the summer and two days in the winter. And everyone can have something installed for under £500.
Just my two penneth....

KristianS

MrMessy Do you have a price per kWh drop in April? Mine is dropping by 25% and so brings back into play arbitrage as a viable option again..... possibly...

johalareewi

I'm going for the 'minimise grid import' method and when i have to import, get it as cheap as possible.
I'm still on Agile import and fixed variable export (soon to be 12p).
Exporting excess solar is fine but dumping battery to grid isn't really cost effective for my system unless there is also a price plunge where I get paid to charge the batteries and get paid to export.

MrMessy

KristianS we've had our system a little longer than you. At the time of installation, our thoughts were to minimise grid use and self consume as much solar as possible. Not unreasonable as we're off-grid for water, gas, phone, sometimes electricity, and besides, export with Octopus was 8p/kWh at the time (unless you fancied your chances on Agile). The move to 15p was quite a surprise, but one which we gratefully accepted, and have made use off.

Like you say though, it was never sustainable and I'm only surprised they haven't dropped it further, like EON.

Roll on V2G.

KristianS

Also.... the alternative is to switch (as suggested in the email from Pete Miller at Octopus) to Aglie Outgoing for Export
Energy Stats UK >> North Western Agile Outgoing Price over the last 3 years or so...
While in 2021 and 2022, that would have been very lucrative indeed, the last three years it has been a more sensible price and so expect on average during the peak of ~ 14-17p / kWh [other regions will vary slightly] and so once again, is not going to make you a fortune.

MrMessy

KristianS Mick's an encyclopaedia (do people even use those any more? Do people even know what they are? 😆) of useful information. I read pretty much everything he puts out. It helps that he's on IOG and has a Vaillant ashp.

WindyMiller

In January and February I minimise the grid and use the cheapest Agile slots with no export except...

When Agile slots are below 13p I'll import to export later based on Eon giving me 16.5p and losing 20% energy round trip.

In the summer I charge overnight so that I can export all solar but keep enough for the peak slots between 4pm and 7pm.

Between these periods I use one or other method depending on slot price and expected solar.

If I was on the other tariffs this method still works until the difference between cheapest import slots and most beneficial export slots becomes less than 20% where I would revert to using all solar and minimising grid.

Eon have not said what they will do with export rates but it renews for me every May and they could reduce them then.

MrMessy

WindyMiller how do you have import with Octopus, but export with EON?

I know EON have dropped export to 6p/kWh for smart tariffs. No idea how that would work for you though.

KristianS

MrMessy Have you heard of Axle Energy ?
They are offering a £1 per kWh for every time they need to assist the grid. They expect each user to get to about £10 per month.

Earn £1/kWh during grid events and at least £10/month guaranteed

Feel free to use my Referral Code to sign up, and we will both earn £25. It is beyond simple to do and doesn't require you to stop using your existing tariffs.
If you want some information outside of Axle - See Gary Does Solar video here>> Gary Does Solar >> Axle Energy: Energy Trading for details. Gary has had a lot of sign-ups.

WindyMiller

MrMessy Eon were my installer so they set up the export SEG at 16.5p to renew each year in May. Shell were my provider which got transferred to Octopus. Then I went onto Agile Octopus with no requirement to transfer export SEG.

KristianS

MrMessy Yeah, he is! I must follow him more closely

MrMessy

KristianS Yes, I've seen various bits of info regarding Axle. I've been umming and ahhing for a while, and there's been people posting their links all over FB and elsewhere for a while.
However, as you seem mostly sensible, there's £25 coming your way. 🙂 🤑

KristianS

MrMessy I too have been tracking for a little while, but with Gary's interview with "Archie", it pushed me over the edge.
I do try... mostly... thanks

KristianS

Looks like my first session has been allocated for tomorrow. I have been notified by my Home Assistant integration as well as by email.... Let's see what happens tomorrow.

MrMessy

That seemed to go OK. That's my 5kW hybrid maxed out.

Be interesting to see how long they keep paying out at £1/kWh, now they seem to be gaining some traction.

KristianS

MrMessy
I am pleased you had success
The irony, mine failed to Export. They managed to send commands that turned off Eco Mode and set the discharge times, but nothing else, so my system just sat there idling and then Importing when I turned something on.
I got a response from support, but they don't yet have a Test Export facility. It is coming soon.

KristianS

MrMessy
So, although Axle failed to automatically set my setup to Export, I did however manage to manually engage during the desired Export window.
That was worthwhile

KristianS

MrMessy I have another session planned for 17:00 - 18:00 this evening? Do you?

MrMessy

KristianS Yep, same times. Clear blue skies here, so may even spew out a little more from my west facing solar. 🤞

KristianS

MrMessy I have to admit.... this is getting quite a good rate of return...