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given the hammering they have been getting on their facebooks for challenging people exporting brown power (charging at night and then exporting in the day) i suspect its to make it less lucrative to do so. 

 


 
Posted : 13/11/2025 10:47 am
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Ahh, OK.  I'm not sure I blame them [EON] to be honest although it must be a bit of a blow to those who bought [extra] batteries partly based on returns from doing exactly that.


 
Posted : 13/11/2025 11:03 am
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re, going off grid

so basically in my situation id need like 20 kw of panels, x5 what i currently have..and god know how much extra battery to have a chance

but.. then in summer id be producing 10x what i actually need.. and binning most of it off, and missing the 15p kw/h potential solar return from octopus, so say 90x15p £13.50 a day in generation, just so i have the capacity for when it's rubbish out

basically, it makes more sense not to off grid unless you actually do have to go offgrid.  the 46p/60p standing charge (in my area) is easily offset


 
Posted : 13/11/2025 11:55 am
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it must be a bit of a blow to those who bought [extra] batteries partly based on returns from doing exactly that.

 

that would be pretty stupid as its in the T+C not to do so. 


 
Posted : 13/11/2025 12:35 pm
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Posted by: trail_rat

 

that would be pretty stupid as its in the T+C not to do so. 

but quite a lot of people still do [going off what I've read on the octopus forum which is inhabited by people from all the providers inc EON]


 
Posted : 13/11/2025 1:56 pm
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i guess the few can be thanked for screwing the many.  Much like our political system really 😎 


 
Posted : 13/11/2025 2:31 pm
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There's specualtion that octopus may follow suit and reduce the export payments.  


 
Posted : 13/11/2025 2:59 pm
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While the grid needs the extra capacity at peak demand time, I wonder if the real reason for SEG being slashed is commercial battery storage operators and gas turbine operators, who make their profits during peak demand, peak wholesale price periods?

 


 
Posted : 13/11/2025 3:55 pm
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I mean renewal offers are always bad, I expect when my deal ends I would need to look at another supplier to get a good deal and then repeat at every renewal. 

I just wouldn't expect an electricity supplier to bend over backwards like Sky or Virgin might for TV or Internet for example. 


 
Posted : 14/11/2025 2:26 pm
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Anyone familiar with Axle Grid Services?  They're supposedly paying £1/kWh if you allow them to use your battery for grid balancing, but don't need exclusive control so you can still export at the normal rate (though not much exporting being done today!)

 

Axle Grid Services | Get Paid to Support the Grid

 

Edit - FWIW I've just signed up so will report back.  If you're interested in signing up let me know as there might be something in it for both of us 😀

 


 
Posted : 09/12/2025 11:14 am
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no, but signed up, and an instant 20 quid credit


 
Posted : 09/12/2025 11:31 am
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ah, was gonna come back and say there 25 for referrals, each.. failed at that one

 


 
Posted : 09/12/2025 11:32 am
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If you use HA they even supply the YAML config to set up a sensor to detect when their events are so you can use that to trigger an automation to adjust whatever else is controlling your inverter and avoid conflicts.  


 
Posted : 09/12/2025 11:39 am
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oo they do? what... amazing, i was just setting up HA to manually import the details, i will look for it


 
Posted : 09/12/2025 11:48 am
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Do report back, curious about this even if Sunsynk isn't listed as compatible at the moment. 


 
Posted : 09/12/2025 12:00 pm
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HA Setup here:

Axle Grid Services | Get Paid to Support the Grid


 
Posted : 09/12/2025 12:02 pm
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Update - just had an email confirming an Axle export event tomorrow morning at £1/kWh (my first). I'll let predbat know that I'm expecting to export during that time so that's factored into the plan, then set it to read only mode before 8am and see what happens. Will update after.


 
Posted : 15/12/2025 3:14 pm
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yer ive got an automation that has fired that into predbat as it was announced, i need to check what it does after the event before i put the automation out.


 
Posted : 15/12/2025 6:01 pm
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There's a few people building automations for predbat so I've borrowed a lot from here

https://github.com/springfall2008/batpred/issues/3051


 
Posted : 15/12/2025 7:08 pm
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So the Axle VPP event was 8-9 this morning. They didn't trigger my export until about 8.10 but then it exported at around 3.6kW for the rest of the hour so I reckon that's about 3kWh of export. They say my account should be credited within 48h so at £1/kWh that should be about 3 quid from Axle plus the normal 45p from Octopus.


 
Posted : 16/12/2025 2:00 pm
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Posted by: thepurist

So the Axle VPP event was 8-9 this morning. They didn't trigger my export until about 8.10 but then it exported at around 3.6kW for the rest of the hour so I reckon that's about 3kWh of export. They say my account should be credited within 48h so at £1/kWh that should be about 3 quid from Axle plus the normal 45p from Octopus.

Which of the Axle options did you choose? Fully Managed or Grid Events only? 

 


 
Posted : 16/12/2025 2:23 pm
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Events only - I normally use predbat as it's fully aware of car charging slots, solar forecast, octopus free electricity and saving sessions and typical load.

Reminder that they offer a £25 referral bonus if anyone's thinking of signing up 😉


 
Posted : 16/12/2025 2:28 pm
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Posted by: thepurist

They say my account should be credited within 48h so at £1/kWh that should be about 3 quid from Axle plus the normal 45p from Octopus.

I don't understand how they manage to do it but that's nice!
I was almost jealous until I remembered the FIT payment I get for every kW I produce 😉


 
Posted : 16/12/2025 2:43 pm
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Posted by: thepurist

Events only - I normally use predbat as it's fully aware of car charging slots, solar forecast, octopus free electricity and saving sessions and typical load.

Reminder that they offer a £25 referral bonus if anyone's thinking of signing up 😉

Poo, I signed up not long after posting! 

 


 
Posted : 16/12/2025 4:14 pm
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So Octopus are cutting their fixed export rate from 15p to 12p per kWh. I'm on IOG so charge car and house overnight at 7p which isn't changing bar the 6 hour car charging cap which isn't an issue for me.

Are there any competitors that are worth looking at? Eon have a cheaper EV tarrif but if you're on that it looks like you're limited to 6p(ish) for export so that's not viable. Good Energy have a decent export rate but their EV tarrif is at 8.5p and the cheap window is shorter than Octopus. And Octopus plays nicely with Home Assistant and predbat so that's another point in its favour.


 
Posted : 17/02/2026 4:09 pm
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I'm a bit late to this party, and apologies if this has been covered somewhere in the past 1600 comments. But is there a go to website for figuring out what I need to do, and get for a hobby type set up? I'm thinking workshed - panels on roof to charge up some smaller batteries to power lights, and keep battery tenders on the go...

Cheers!


 
Posted : 17/02/2026 6:52 pm
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Not that I know of.  But in essence, you need panels, a hybrid inverter and a battery compatible with your inverter.  Start by thinking about how much roof area you have and want to cover.  Panels vary in size and generating capacity but all are now around 20-24%. Meaning that size=power.  Once you know your area and find the right size panels to get the max power out of the area you have.  Use the total power to find a suitably sized hybrid inverter and use the inverter type to find a compatible and suitably sized battery.  The rest is just wiring and grounding.  


 
Posted : 17/02/2026 8:58 pm
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Posted by: Daffy

Not that I know of.  But in essence, you need panels, a hybrid inverter and a battery compatible with your inverter.  Start by thinking about how much roof area you have and want to cover.  Panels vary in size and generating capacity but all are now around 20-24%. Meaning that size=power.  Once you know your area and find the right size panels to get the max power out of the area you have.  Use the total power to find a suitably sized hybrid inverter and use the inverter type to find a compatible and suitably sized battery.  The rest is just wiring and grounding.  

Many thanks! I shall measure up this weekend and make a start to this next project...

Cheers!

 


 
Posted : 18/02/2026 2:36 pm
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So Octopus are cutting their fixed export rate from 15p to 12p per kWh. I'm on IOG so charge car and house overnight at 7p which isn't changing bar the 6 hour car charging cap which isn't an issue for me.

Are there any competitors that are worth looking at? Eon have a cheaper EV tarrif but if you're on that it looks like you're limited to 6p(ish) for export so that's not viable. Good Energy have a decent export rate but their EV tarrif is at 8.5p and the cheap window is shorter than Octopus. And Octopus plays nicely with Home Assistant and predbat so that's another point in its favour.

Reminds me, I had a letter from EDF as my export tariff is about to end, have to call them to agree the next rate for some reason, will do that and report back! 


 
Posted : 18/02/2026 2:40 pm
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Does anyone know about plug in batteries?

What I would really love is a plug in balcony solar setup, but my apartment doesn't have a balcony, so I just want to look at a plug in  battery storage to charge overnight at cheap rate and release during the day as needed.

 

 


 
Posted : 16/03/2026 7:12 pm
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I'm not saying it's a bad idea, but I have some questions/points:
- How would you get cheap rate... Do you have an EV?
- Even assuming free electricity a 2kW "station" seems to cost about £800 on average so £800 / £0.60 = 1333 days to break even. Doesn't seem very good numbers.
- balcony PV isn't allowed in the UK yet although it's being looked at. So I think you'd need some way of isolating the house in the event of a power cut.

If the numbers were better I'd be interested though.
(I think batteries still struggle to make economic sense unless without being paid for export .... And that's reducing now.)


 
Posted : 16/03/2026 8:06 pm
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Posted by: sharkbait
How would you get cheap rate... Do you have an EV?

Octopus Agile, is usually cheaper overnight and daytime away from peak time. Think you can automate battery charge based on the rate using IFTTT or go full Home Assistant on it.


 
Posted : 16/03/2026 8:50 pm
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Ahhh, OK.... I'm on agile too.
It's a bit cheaper but id say the average over night is about 12p is guess. Obvs not.last night 😉
One thing I would say is that the Octopus IFTTT integration is not trustworthy.
You'd be better rolling your own.
(I just run a bash script on a pi ever 30 mins to get the new price and then switch stuff on and off based on that)


 
Posted : 16/03/2026 9:46 pm
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It transpires my house has MCS certificate, despite being told before it does not.

I have 6x Viridian panels and Growatt inverter with estimated 1540kWh generation annually. 

Currently on Octopus Intelligent Go, EV X 12k miles, a person at home all day, 4 bed/4 people house.

Getting better at using cheap overnight AND load spreading through the day to maximise any solar. We do plan to use as much as we can locally rather than export.

Is there any downside to signing up to Outgoing Octopus (flat rate) on top of Intelligent Go (which is how I understand it works...) and selling on the odd occasion we have some "spare" electricity? 


 
Posted : 17/03/2026 3:35 pm
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That the 12p rate? If so thats what I'm on, so no downside. You're coming into right time of year now to export as much solar as you can, this is where batteries can help to store excess to use at at night and poor solar days but that's another topic.

 

so far this year I've generated this 

 

image.png

January was piss poor, but its getting better now 

image.png


 
Posted : 17/03/2026 6:13 pm
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No downside as you get paid more than it costs you overnight. That's is how we are setup except flux outgoing.


 
Posted : 17/03/2026 6:18 pm
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Yes, 12p rate.

I've signed up - seems that I've given free power away again today despite someone being in all day on a PC and a washing machine load done...

 


 
Posted : 17/03/2026 6:42 pm
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If you have a hot water cylinder then you're probably better off using spare power to heat that [using a diverter].


 
Posted : 17/03/2026 7:48 pm
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Posted by: sharkbait

If you have a hot water cylinder then you're probably better off using spare power to heat that [using a diverter].

 

I need to properly do maths on electric use, selling solar at 12p Vs gas unit cost and efficiency.

First glance seems use gas for hot water, use as much solar as you can buy oad spreading through the day, sell at 12p what is spare, charge car and big loads overnight at 3.5p...

That may change if I look at a battery. 🤔

 


 
Posted : 18/03/2026 1:12 pm
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i have a PV diverter - we never use it.

Charge the batteries , sell the excess. 

 

There is never excess at a points in the year where id need  to be heating water. 


 
Posted : 18/03/2026 2:05 pm
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Posted by: trail_rat
Charge the batteries , sell the excess. 

He's not got batteries - but he does have a bit water tank.
So he's have to spend a fair chunk before he start selling those units for 12p.
Also, maybe he wants to reduce his carbon emissions (rather than make a few quid) which using the power to heat water will do.


 
Posted : 18/03/2026 6:58 pm
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Posted by: sharkbait

Even assuming free electricity a 2kW "station" seems to cost about £800 on average so £800 / £0.60 = 1333 days to break even. Doesn't seem very good numbers.

certainly no expert but that works out at about 4 years no? how much do the regular rooftop installs take to break even? 12 years?


 
Posted : 18/03/2026 10:33 pm
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I really need to sit down and go through this thread to see what we are best doing. (Moving into a smallish (110m2) 4 bed house in East Yorkshire, built in 2003. EPC C. Gas heating, electric water heater faces ENE and WSW) It would seem daft to wait a year or three before acting rather than crack on and start saving money and investing in the property straight away.


 
Posted : 19/03/2026 6:42 am
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Posted by: Del
certainly no expert but that works out at about 4 years no?

Not really.
Because the only way to get that free electricity is through solar - and there won't be enough spare generation for 6 months of the year so that 4 years then becomes around 8.

And I don't think the batteries are expected to last that long if used in that way.
Solar panels are guaranteed for around 25 years (and I believe their payback is now around 7 years)


 
Posted : 19/03/2026 8:16 am
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Apologies as I'm sure this has all been covered, but does the cost of a new solar install ever stack up on a modern new build?

We just had a bit of a hard sell from a company we contacted for a quote.

£13,500 bought us 8 x 450W panels, invertor and 5.76kWhr battery, this would supplement the 6 x 300W panels (no battery) that came with the house.

Predicted annual generation is 5400kWhr including existing panels (I checked this against other, independent calculators such as this one https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html&source=gmail&ust=1774512820560000&usg=AOvVaw2e0hqTBW5Bh6uqU9_Pr-z e"> https://re.jrc.ec.europa.eu/ pvg_tools/en/tools.html which all seemed to agree more or less, including a 14% inefficiency factor).

This easily covers our electrical consumption for the year, saving us £40-£50 (I haven't figured out what component of our bill is standing charge which presumably we still pay!). Salesperson was adamant that we would recoup a significant extra sum from SEG but even his calcs (and the other independent calcs I did) only suggest £300/yr SEG, assuming we get 15p/kWhr which is sounds might not be guaranteed.

At ~£162/month for ten years on finance to pay for the installation, AND since we would still be paying for gas fired central heating and hot water (~£60/month) we're basically out of pocket for the lifespan of the install. Salespersons calcs (appended at the back of the quote) actually show break-even at yr 25 🙄.

I would have liked to do it just for energy independence and because it feels like the right thing to do, but I just can't square the figures. Am I missing something? Is SEG the cash-cow the sales guy suggested it might be? I'm wondering if we would be better off just sticking a hot water cylinder on to our existing install and using a smart tarrif to top it up overnight...


 
Posted : 25/03/2026 9:23 am
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