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Solar Panels UK - is it worth it?
- Thread starter jdwuk
- Start date
So my research on the Growatt kit is not filling me with confidence. They appear to be a budget brand and there is a lot of ‘you get what you pay for’ type of feedback out there
I’ve just had a good chat with Octopus and they’ve given me a very detailed quote for 16 x JASolar panels, a Givenergy Hybrid 5kw inverter and a 9.5kWh Givenergy battery, all fitted for just over £16k. It’s about £3.5k more than the quote I got for the equivalent size Growatt setup but from what I gather, Givenergy is superior in every way (plus the fitting backed by a company the size of Octopus). The detailed Octopus quote is great and includes estimates on how shading from some nearby trees would affect generation. Payback is estimated at 8 - 9 years. I could even double up the batteries for just an extra £3.5k but that would increase payback to around 11 years.
I’ve got another installer coming to tomorrow to do a quote to include a Solaredge inverter and Tesla Powerwall 2, so will be interesting to see how much more that will come in at.
At the moment I’m leaning towards the Givenergy kit fitted by Octopus, unless the Powerwall quote surprises me!
I’ve just had a good chat with Octopus and they’ve given me a very detailed quote for 16 x JASolar panels, a Givenergy Hybrid 5kw inverter and a 9.5kWh Givenergy battery, all fitted for just over £16k. It’s about £3.5k more than the quote I got for the equivalent size Growatt setup but from what I gather, Givenergy is superior in every way (plus the fitting backed by a company the size of Octopus). The detailed Octopus quote is great and includes estimates on how shading from some nearby trees would affect generation. Payback is estimated at 8 - 9 years. I could even double up the batteries for just an extra £3.5k but that would increase payback to around 11 years.
I’ve got another installer coming to tomorrow to do a quote to include a Solaredge inverter and Tesla Powerwall 2, so will be interesting to see how much more that will come in at.
At the moment I’m leaning towards the Givenergy kit fitted by Octopus, unless the Powerwall quote surprises me!
Pete UK
Member
Thanks, Yeah. Strange and a very annoying waste of time chasing them.
I emailed back and attached their Octopus announcement on 6th September. Also told them they confirmed to me by email that I’d be switching to the 15p rate automatically.
Sunny money: Octopus Energy quadruples export rates for smart tariff customers
Let’s see what happens. Fingers crossed they sort it
They seem to take a day to reply to emails at the moment. But at least it’s in writing then.
Pete UK
Member
Yeah. Much appreciated. More ammunition, if I don’t get any further. Thanks. So it’s actually called “Outgoing Octopus” that I want.
Whoah 60p a day standing charge?
that’s 50% more than here.How’s the generation going?
I’m still struggling along on half a system. Not had to buy any peak yet, so all good for now. Could do with the export tariff being sorted though, as some solar is spilling out to the grid every day at 4p because 2 batteries are out of action. Now it’s 4p, was zero till a few days ago.
Apparently I need a new battery, a new BMS in the other one and a new inverter.
Bit slow with the customer service. Been out of action since 29th July. Very frustrating but not affecting me financially too much at the moment. At least I’ve got a bit of redundancy having two inverters.
I think I’ve been a bit unlucky. But I’m not sure if it’s that or a dodgy batch of equipment.
growatt inverter alone is ~1500 for SPH6000
I got one but in reality - I cannot fault it. it works, so not sure where issue is...
have you tried to ask Otovo if they provide other options for inverters and batteries?
Powerwall alone will be 10+k...
Powerwall showing on Tesla GB site as £6000 including VAT. Not sure if this is for v3 or not.
I’ve done a lot of research across the internet and Growatt consistently comes up with less positive reviews and feedback. Of course there are people that have had good experiences but it feels like a bit more of a lottery, particularly when you hope to have them for at least 10 years.
Givenergy on the other hand seem to have a much better reputation overall. I believe it also integrates with Octopus tariffs like IO and Agile.
The fitter I have coming tomorrow to do a quote said the Powerwall 2 is around £7500 and that includes the gateway.
Or I could have 2 x 9.5 Givenergy batteries for about the same price through Octopus.
I’m not knocking Otovo by the way. The guy I’ve been dealing with has been great. Very professional and not pushy. I’d definitely recommend having a chat with them to anyone that is not looking to spend out on Givenergy or Tesla kit.
Ask them to explain this:
Only negatives I hear with Giv is that they're not the fastest to get an engineer out (Potentially 4-6 weeks of lost production). But it's a long term investment, and it's not outside of industry norms...
Octopus fitted mine (10 panels, 3.6kw hybrid, 9.5kWh). They did a good job start to finish, and aftercare has thus far been good.
I don't know your usage patterns, but the reason your payback jumps with 2 x 9.5kwh is that the setup is probably too large. You've got to remember you need to cover the average day, not worst case. 11 years payback pushes you outside of warranty periods.
Also note that 2 x 9.5kWh will only just about fully charge in the 6 hour IO window, and wouldn't in a go window.
I suspect you'd be better off with a single 9.5, or 9.5 + 5.2. But again, don't know your usage patterns
Have you tried an online switch using this link Outgoing OctopusYeah. Much appreciated. More ammunition, if I don’t get any further. Thanks. So it’s actually called “Outgoing Octopus” that I want.
Whoah 60p a day standing charge?
How’s the generation going?
I’m still struggling along on half a system. Not had to buy any peak yet, so all good for now. Could do with the export tariff being sorted though, as some solar is spilling out to the grid every day at 4p because 2 batteries are out of action. Now it’s 4p, was zero till a few days ago.
Apparently I need a new battery, a new BMS in the other one and a new inverter.
Bit slow with the customer service. Been out of action since 29th July. Very frustrating but not affecting me financially too much at the moment. At least I’ve got a bit of redundancy having two inverters.
I think I’ve been a bit unlucky. But I’m not sure if it’s that or a dodgy batch of equipment.
Provide your MCS details etc. Mine just sailed through.
Thanks, that makes a lot of sense. A single 9.5kWh is probably only slightly too small but should allow me to charge the battery and top up the car in the 6 hour IO window (I think). The almost 3 years faster payoff is more attractive and as you say is within the 10 year warranty.
The 13.5kWh of the Powerwall should more than cover average use. Fitter is due in a couple of hours to prepare a quote for that so will be able to compare prices.
bearing in mind if you're on IO the battery only has to cover 18 rather than 24 hours, and even in winter you'll get a smidge of solar to help a *bit* other than really bad days which you can treat as edge cases that don't justify a second battery.
I'm still tempted to get a second - if my wife goes crazy with the tumble dryer or my son decides to do a separate wash in the middle of the day and wears me down with 'why do I have to wait for overnight' - that gives me peace of mind which has its own intangible value. but down the line once I've fixed the roof and recovered a bit from that...
More directed at notmeguv..
With the PV and Solar, you only really need the battery to cover between 5:30 and say 9:30 depending on orientation. *most* days you'll have enough PV to cover baseload and cooking lunch, if not enough to fill the battery totally and export. Then maybe 5-6pm it's back onto the batter until 11:30pm.
The depths of winter isn't most days, and even then, you get some OK days.
Extra batteries need to cover your needs on the majority of days, otherwise you'd cheaper running off grid, and just living with the fact that some of your power on some days will be 30p/kWh, but that this is still cheaper than spending another 3 grand on a bigger battery. It's really important not to over-engineer
Tumble and Washing - hopefully the exception rather than the rule, but running through a few kWh at 30p/kWh probably won't add up. (If the tumble is heavily used, then a heatpump tumble might make sense... Especially if you have a replacement opportunity). Good load shifting hygiene is useful for making the whole system pay back.
One other thing to ponder. You probably won't know exactly how much battery you need right now, but the odds are that the cost of batteries will come down over time (Sodium would seem a good fit for the usecase, lithium is in high demand as a result of high costs, etc), so maybe extra capacity is a mid-life refit rather than a "now".
PS, as EV and solar with battery becomes more common and there is more off-peak, it does raise the question of how long the "good days" of super cheap off peak will continue. I'd be concerned about making a large long-term investment just on the basis of cheap off-peak.
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I believe the Giv warranty is now 12 years.
My setup is 4.6kwp panels + 9.5kwh battery. Instead of a second battery, I opted for a hot water diverter which typically soaks up 3–6kwh a day of excess.
We’re on Octopus Tracker at the moment as it’s working out cheaper than IO but we were on IO for a month and got used to scheduling washing machine and dishwasher to run in the off peak window.
Our old tumble dryer is a vented and uses a horrible 4.5kWh per load so I’m in the process of deciding which heat pump type to buy. Looks like it will be a Samsung which is at least a 3rd of the energy usage of the current one.
Bearing all that in mind and the fact I hadn’t thought about only needing to cover the shorter peak period, I reckon the 9.5 battery will be enough on most days.
I'm not clear on how that's fed through to Octopus, as the Giv 12 year warranty requires "inspections" during the timeline, and octopus were previously offering 10 years with "their own arrangement with Giv"
Main aim with the battery is to keep enough to get you to the end of the day. Maximising value over exporting is also useful - suspect most people here also have an EV to dump power into, and hot water tanks, moving washing around, etc all make sense.
Currently with the IO + 15p ongoing, it makes most sense to export any spare. But that will no doubt change over time.
Odds are you'll want intelligent octopus or agile. The heatpump drier is loads better than our old vented, and also feels a lot safer to use overnight.
Always difficult to size things up before you buy, but 9.5kWh is a big battery by most standards
