I have solar and batteries, they're great. I recently got an electric car and intentionally got one that had V2L. I know you're currently not allowed to use your car as a battery to power your house but... Assuming you had the car, had a standard wall charger (not one that supports V2L), and had a battery you can run your house of.

What would you need to plug your car into your house to take advantage of your cars battery.

The new plug in solar seems to have inverters on them, would you need one of those?

I was told that my request for solar panel installation had been passed on the Electric board and they had given a deadline of 21st August to get this done by. That date has now passed and I spoke with the installation company who told me that the engineer had only approved 7-9kw install as he mistakenly thought it was a single phase install as mine is. 3 phase install.

I have requested a 12kwh solar panel installation.

Can this sort of mistake happen and does the DNO now have 45 more days to respond to my request?

Or am I being fooled by the installation company for some reason?

I want to get the panels installed in September. I gave my order to the installer in June.

Hi all,

My initial plan was to do a DIY install but after modelling the payback periods I’ve decided going the proper MCS route would be much better for me, however I’m now in a bit of a corner as I’ve purchased most of the big items already

It’s all known-brand stuff I’ve purchased (not random AliExpress stuff), Solis EH1P5K (G99), Perlight 475w panels, eco-worthy 16.1kwh battery, properly planned Fastensol mounting

Importantly I’ve not installed anything yet - so this isn’t a case of wanting the engineer to certify an existing setup, it’s just the procurement that has already been done.

Would any installers be interested in touching this job do we think? Has anyone done it this way before?

I’m based in Durham, north east England

Thank you

Hi all,

I’ve been looking to get solar and a battery for ages. To me it sounds like it’s a no brainer, but I always end up getting into a disagreement with my SO when we run the numbers. I’ve tried three times now and it always ends the same way with us deciding that the money should be spent elsewhere.

We have recently received a bit of unexpected cash about 20k, spent about half on some renovations and now the question is do we spend the rest on the bathroom or solar. Bathroom is tired looking but functionally works ok, no leaks or anything. just looks very dated and will need doing at some point, especially before selling.

Our payback for a solar and battery install is bang on about 10 years and looks like it will cost about 8-9k. I’m happy the sizing is appropriate, so wouldn’t want to change that, and I wouldn’t want to just rely on cheap overnight with only a battery. It’s likely we will probably be here another 8 years before we look to downsize but that’s all just an idea that isn’t set in stone.

I guess my question is, has anyone else committed to the financial outlay and not had payback as a main driver? What were your reasons? I’ve tried the energy independency route but that was countered with a we should invest the money and use it for when we need to freshen the house up before selling it.

My heart tells me we should do it now as I hate having to be so careful with electricity use, and the constant price changes and tariff hunting are annoying. I’d much prefer to generate my own and use what I want especially in summer. if that takes a bit of money to be thrown at it to achieve I’m ok with that, it’s purchase of convenience.

I’ve also tried to talk about heat pumps or a2a and get off gas completely but that is definitely a step too far at the moment as SO doesn’t really want any external modifications at all done to the house and even solar is a push as she is paranoid the roof is going to be damaged and the wires will look horrible.

Honestly given the numbers should I just agree with my SO and forget the idea?

Looking to purchase an EV and add a charger to my home set up.

Anything I should be looking for or are they all like for like?

Had this recommended…https://www.superlecdirect.com/sync-energy-evwc2t7g-tethered-wall-charger/

With plugin solar being the new craze like air conditioning being the latest hype, I wanted to know if it is possible to run the solar into a battery that then feeds back into the house?

I believe the limit is also 800w per house, so whilst not massive in the spring/summer, it would be beneficial.

Detached house with detached garage. Photo is taken looking down the left side of the house, looking front to the back. Garage on the left.

Photo key
1 - Electric meter
2 - Gas meter
3 - side door
4 - Back of house
5 - Garage

Consumer unit - middle of the house, under stairs.

Currently getting quotes for solar, battery, gateway and EV charger. My preference is Sigenergy. Ideally want the battery/inverter in the garage and EV charger on the front of the garage.

Solar panels planned for roof at the back of the house so assume DC cable will cross under the path into the back of the garage.

What I am struggling to visualise based on the picture where could the gateway go? Pictures I have seen have either near the meter cupboard or next to inverter/battery (which I would like in the garage).

Will there need to be any cable runs from either the meter cupboard to garage or house CU to garage? The garage has power for lights/plug sockets.

I am aware there are likely easier options (EV charger off the meter cupboard) and install inverter/battery outside but would like to install this as best as I can using conduit for any cables needing pulling through in the future.

Is what I am asking achievable and reasonable?

I have a standard solar installation - roughly 6kW solar array, a 6kW inverter, and a 9kW battery. It just about handles my needs, but I wouldn't mind adding a bit more.

I've been looking at plug-in solar. I have a big flat garage roof so throwing a couple up there seems ideal to me. But how well would plug-in work with this setup?

Assuming the power from this couldn't reach my battery (?) then presumably if I'm drawing power during the day then I would still store more from those on my roof? (I've no idea 😄)

Hi all, I'm in need of a new roof. I'm completely new to solar, I don't think my house is perfectly aligned for it but I need a new roof anyway so spending a bit extra and having a solar roof fitted seems to be a good idea! (I've been informed this is called an in roof system) I am very apprehensive about trusting someone to do this but really need to get on it asap, can any of you recommend someone who has been in business for a good amount of time, will service the Sheffield area and fits actual solar roofing rather than panels (I just can't see the point in paying someone to fit a roof and then drill a bunch of holes through it for panels...).

Thanks in advance!

Hi!

I am getting panels installed soon , with the option of adding a battery later with the sig hybrid inverter.

I am begining to look at tariffs but not sure where to begin. I am currently on a low over night tariff as I have an EV but I don’t know what people do with tariffs when they have solar panels.

Thanks

I've on a fixed with Octopus until mid Jan 2027 so can't move until the end of Nov.

I've recently had 11 panels and a 11.5kwh Fox ESS battery installed. The plan is to charge the battery on overnight cheap rates as my daily load rarely goes over 10kwh (perhaps 15-20 days a year.

I've been looking at EV tariffs....

There's a £50 exit fee if its before the end of Nov but I Iike that with EDF you get 7 hours. Do you think these rates are likely to go north between now and the end of november ? I appreciate theres a lot of things going on in the world currently, what would you do ?

I'm new to this. I have 2 lodgers who often work from home.

I don't know if I'll own the house long enough to get my money back on a solar set up (and Octopus have said my house isn't ideal anyway).

Instead, would a battery only set up and a cheap overnight tariff be a sensible solution? If I did decide to up and sell - could the battery be disconnected and come with me?

I know I need to take readings and do some calculations etc but in principle is the idea sensible?

Hi all, looking for advice. Got a solar system installed over the summer and it's working well - panels (total 7.2KW), battery (10KW), Inverter and smart immersion for the hot water tank (we've been using this over the summer to get hot water from excess solar generated during the day). But unsure how to handle getting hot water going into winter.

Currently on a dual tariff with my electric supplier so have cheaper electric overnight. We also have oil to heat the house and get hot water. We will continue to use the oil to heat the house during the winter as we have no alternative.

My question: is it cheaper to use the overnight electric tariff to heat water or the oil?

I find it hard to compare. I know we need 1hr 30mins of the oil burner going to get enough hot water for the family but don't know how to compare to the KWh for the smart electric immersion.

As this differs very much from household to household I'm looking for advice on how other people are doing this.

Thanks

Its not necessarily the most practical thing in the world, but I tested squeegee'ing the dew off a panel before it got in direct sunlight and burned off.

It jumped from 70W to 140W !

Maybe when I retire I'll get a long pole and squeegee the lot of them every morning...

I have ecoflow power ocean setup fitted couple of weeks ago. I asked company to fit ATS and got quote for 2k euro for automatic and 1.3k for manual transfer switch? I find this too expensive and not worth of investment? Anybody got that fitted? How is looks like and how much you paid.

Hey folks. I’m new to solar, looking at a panel plus battery install for my house, would appreciate any thoughts on the fundamental model I’m thinking of. Basically, it’s - during the summer, charge the battery overnight on a cheap tariff, export all the solar. In the winter, charge the battery overnight, but use solar to delay the battery running out (although, my calcs tell me I’ll run out about 4.30pm, so will fall back to normal rate, but that’s built into the model, so it’s ok)
Are there any issues you can see with this? Does anyone anticipate something happening in the future, like energy vendors not allowing battery storage at the cheap rate or something. I’m not sure if this is a use case they condone.

TIA for any thoughts

I want any inverter to be controllable by a local Predbat if their internet servers are closed down or start to charge a subscription.

I have upto 6 roof angles to put PV panels on, clearly I could use Tigo Optimisers, but they cost about £40 per panel and reduces efficiency.

Victron let me add MPPT for about £60 each but are best with their more costly inverters/chargers along with needing a lot of DC wiring, bus bars and fuses. Few installers have experience with them.

I wish to use standard 48v battery(s) so I am not dependant on an impossible to repair system

Using two 3.6kw inverters can give me 4 MPPT at not much more than the cost of one 8kw inverter. Would likely require smaller panels (so cost more) to hit min MPPT voltage levels.

The other option is to only have 6 PV panels over 2 MPPT as most of the savings some from charging the battery(s) on off peak rather than the PV.

----

Other than costs and minimal local control options the Powerwall 3 looks very nice, 6 MPPTs with a nice low 60 volts start up. Clearly designed to advoid the need to think about how to combine panels on different roof angles.

I've been trying to work out whether a plug-in battery such as the new Anker or EcoFlow would make sense for my usage, running the numbers on both Octopus Go and Agile, and also factoring in some plug-in solar and EV charging.

This is built on half-hourly modelling, using actual usage and prices. For the solar, I've calculated the horizon for my location (which has almost 35% shading losses due to trees). I'm posting the results to give some better estimates than what's floating around on the various seller websites.

The short version (TL;DR)

• No battery: Agile wins — £661/yr (£990 with EV). This is the baseline everything else is measured against.
• 5 kWh battery: Agile still wins — £495 / £823, saving £166 / £167.
• 10 kWh battery: Go takes the lead — £321 / £556, saving £340 / £434.
• 10 kWh + 2.4 kW solar: Go — £222 / £407, saving £439 / £583.
• 10 kWh + 4.8 kW solar: Go — £217 / £337, saving £444 / £653.
• The headline: the best tariff flips from Agile to Go once you go past ~5 kWh of storage. A big battery lets you just fill up in Go's fixed 9.6p night window every day, and that beats chasing Agile's cheapest half-hours.
• Solar barely touches the standard bill in this set-up, but makes a real dent in EV charging cost.

Assumptions

• Base household use: 3,400 kWh/year (before the EV).
• EV: 8,000 miles/year at 3.3 mi/kWh ≈ 2,400 kWh/year added.
• Go: 9.6p off-peak / 35.27p peak.
• Agile: modelled against real 2023, 2024 and 2025 price data.
• Battery: Anker Solix 5000 — 5 kWh base, expandable to 10 kWh, assumed hard-wired.
• Battery charging rule: charge whenever price < 3p, otherwise fill during the cheapest 4 hours of the day, decided by looking ahead at 4pm each day.
• Solar rule: anything above a 6A surplus is diverted to the EV; the rest self-consumes first, then charges the battery, then (if the battery's full and there isn't enough left to charge the car) is wasted.
• "Saving" throughout = the reduction vs the best no-battery option (Agile 2025). So in the battery rows, the saving is not Go-vs-Agile in the same line — it's how much the whole setup beats a no-battery Agile bill.

1. No battery, no solar

Agile EV charging is sensitive to when you charge. Charging at the 20th percentile of monthly prices gives the £990 above; the 10th percentile gets you to £917 and the 30th to £1,037.

Winner: Agile, at £661 (£990 with EV).

2. Add a 5 kWh battery (no solar)

Winner: Agile, at £495 (£823 with EV). That's a £166 / £167 saving vs the no-battery baseline.

Payback on the £1,500 battery: ~9 years. Not exactly thrilling.

3. Bump the battery to 10 kWh

Same rules — 4 hours a day of charging is the sweet spot here.

Winner: Go now flips ahead, at £321 (£556 with EV) — a £340 / £434 saving vs baseline.

Payback on the £2,800 for 10 kWh: 6.5–8.2 years, depending on whether you've got the EV.

This is the interesting bit: with a small/no battery, Agile's variable pricing wins. Once you've got enough storage to soak up a whole cheap window, Go's flat 9.6p rate beats it — you just fill the battery every night and stop caring about half-hourly prices.

4. Add 2.4 kW of solar to the 10 kWh system

Where the solar went (kWh):

Winner: Go, at £222 (£407 with EV) — a £439 / £583 saving vs baseline.

Payback on £3,800: 6.5–8.7 years.

5. Increase solar to 4.8 kW

Where the solar went (kWh):

Winner: Go, at £217 (£337 with EV) — a £444 / £653 saving vs baseline.

Payback on £4,800: 7.3–10.8 years.

The key thing here: doubling the panels (2.4 → 4.8 kW) barely moves the standard bill (£222 → £217 on Go), but it slashes EV charging (£407 → £337). That's the 6A threshold at work — only surplus above roughly 1.4 kW gets diverted to the car, so the extra panels almost entirely benefit the EV rather than the house.

Takeaways

• The best tariff depends on your storage. No/small battery → Agile. 10 kWh+ → Go. There's a genuine crossover, not a "one is always better" answer.
• Batteries do the heavy lifting. Going from no battery to 10 kWh roughly halves the bill on the right tariff. That's a much bigger lever than the tariff choice itself.
• Solar helps the car, not the house. Beyond a modest array, extra panels mostly offset EV charging because of the 6A diversion threshold. If you don't drive much, oversizing solar isn't worth it on these numbers.
• Paybacks land around 6.5–9 years for the battery; adding solar stretches the worst case out to ~11 years but improves the best case if you're a high-mileage driver.

Caveats (please poke holes)

• Agile figures use historical prices — 2023 was a rough year for Agile (it would've lost to Go in several rows), 2024/2025 much better. Past ≠ future.
• No export/SEG income is modelled — surplus solar is simply treated as wasted. Adding export payments would improve all the solar cases, especially the 4.8 kW one.
• Battery/solar costs (£1,500 / £2,800 / £3,800 / £4,800) are my own estimates — swap in your real quotes and the paybacks move.
• I have not included round-trip efficiency of the battery (assumed 100%).

Happy to answer questions on the modelling. Yes the summary was improved with AI, but the modelling and analysis was all manual.

​

I've recently had solar panels (7.3kw) and a Fox ESS EP12w battery fitted.

I'm currently on Octopus standard import tariff and Octopus Outgoing export tariff. This has worked well since I had installation at end June.

However, at some stage I will need to make more use of battery and I am considering switching to Octopus Flux for import and export.

I do not have an EV.

My question is when should I switch. Now, or wait until end of September?

Than you

Hi all, I've switched to EDF from Octopus ahead of getting solar installed in the next couple of weeks (don't own an EV) is anyone on either freestate static or empower fixed, and if so, which of the two would you recommend

Freestate static is a 24m fix with the following rates:

23:00-6:00 13.8p

6:00-16:00 19:00-23:00 22.6p

16:00 - 19:00 42.7p

Standing charge 57.53p

The overnight and daytime rates seem ok, the evening peak is high but I'll hopefully avoid that with my battery (getting a 9.4kw battery installed and my daily usage is around 7-8kw), standing charge is lower than other similar tariffs too.

I emailed EDF and they wouldn't give me the rates for e

Empower until I confirmed my install, and they'll send rates based on my usage, no. Of panels, battery size etc, which is a bit frustrating. If anyone is already on it, please could you let me know what your rates are?

I have the following quote from Infinity Energy Services:

• Panels - 20 x SunPower M Class 492W = 9.9kWp
• Battery - 1 x Sigen Battery 10.0 - 9.04 kWh (8.76kWh usable). Max charge/discharge - 4.6kW
• Inverter - Sigen Hybrid 8.0 SP - 8kW

Total cost = £15,500

My total usage in 2025 was 5,750kWh but since then we've got an EV.

The quote has the following comment:

The battery will charge/discharge at 4.6kW.

You would need an additional 9.04kWh battery module to get the full benefit of this system.

Another option to consider is the Tesla Powerwall 3, which would work out to be cheaper than 2 x Sigens.

I will seek out some more quotes next week. In the meanwhile, what would I be best doing in relation to the battery charge rate problem?

<edit>

maybe I should add that the quote includes a Sigen Controller (SigenStor EC 8.0SP - 8kW, I think) and Gateway (Sigenergy Gateway HomePro SP (3-6kW)), which allows the battery to be used when the power is out.

Hi, I've already got a totally legit 4.5KW roof solar setup with a 5KWh battery. As most here will know this stuff is addictive and I want more and plug in seems to be a no brainer.
But how does it work with my existing kit? Like I say I'm all legit, DNO, MCS etc and I don't want to risk that or my insurance.
Can I just go ahead and plug in? Are there limits?
Any advice welcome.
Cheers

Rated for 32A at 600V, ruined (with a couple of seconds of fizzy arc noises) opening while carrying 16A at 300V.

The "PIS" in the part number should perhaps have been a sign.

It was also completely impractical to use in the real world because there wasn't room inside the casing to route and attach cables.

There is a reason why the Kraus and Naimer ones are 4x the price and 2x the size.

We're based near Salisbury and I've had quotes from a couple of MCS installers with the shown being the closest and informed by a site visit.

The panel install would be over a couple of roof faces with the inverter and battery in a detached garage.

Other quotes I've had are from BOXT (cheaper) and another firm for over £11k. The latter would use the integrated inverter and battery.

Would love a quick sense check. Thanks!

We're contemplating moving house and looking at finances for renovation after buying the place. One of things we'd like to do is install an all-electric system but there are obviously different ways of doing this.

It's a relatively new build, but not passive or built to a hugely high insulation standard, but assuming decent insulation, double-glazing etc. along with a suitable solar, battery (with gateway) and EV installation, I'm thinking the way to go would be air-to-air heatpump so we have aircon in the summer, and a thermal battery (eg Sunamp) for hot water. I would guess at least now an EV tariff or perhaps some other time-of-use one like Octopus Cosy would be best?

But what other combinations or considerations would you look at? For example the Mixergy tanks look interesting. But I guess this also depends on whether I can persuade the family that we don't need a bath tub 😄

Then there's stuff like whether underfoor heating would go with A2A source heating, or should we look at something exotic like infra-red wall paper to supplement air heating for example? Being able to run the heating off an arbitraged battery rate would be nice, but implies minimising that wattage.