Upgrade Hybrid Inventor 3.6KW to 5KW.

Hi,
I'm looking at adding more solar panels to my system. Is there a buy back or cost-effective way to upgrade my hybrid invertor from 3.6KW to 5KW?

Regards,

Dan

danerf there's no buy back scheme, so you'd have to sell your 3.6 on ebay or similar, but the warranty won't transfer to the buyer so that could impact resale value.

You'd also have to get approval from your DNO as you're increasing potential export rating

I've been quoted £5,300 for nine panels, two optimisers, scaffolding front and back of the house, labour, fitting panels, changing the 12 panels at the back of the house 1 string and changing the hybrid inverter from 3.6kw to 5kw. The new nine panels will be on string two.
Do you think that's a reasonable price?

danerf 2 optimisers? Is that for a shading issue?

Price looks ok when you break down the costs. 2 or 3 guys all the scaffold.

THALL Yeah, the Apex on front of the house would hold two panels which get shaded

Our Gen1 Inverter was upgraded from 3.6 to 5kW via remote software update (by GivEnergy)
See previous discussion here: https://community.givenergy.cloud/d/1212-inverter-firmware-update-from-36kw-to-5kw

Note that I'm in Ireland, where there's a 6kW inverter output limit on domestic installs - obviously in the U.K. you have to apply to exceed the 3.6kW limit, so your mileage may vary!

danerf Probably a daft idea, and to be honest I don't even know if it is possible. However, could you just use your existing inverter plus another 3.6 with the new panels?
From other posts there are some that run with more than one inverter, but there are problems with them 'fighting' which apparently is going to be sorted before too long?
As I read it there are advantages with two inverters in as much as twice the power is able to be used so that 2 x 3.6's can give you 7.2kW in house to use, great when all the family is round for dinner.
The challenge is export exceeding the DNO limit, so can one (or both) of the inverters be limited to cap the max export? or would the DNO approve 7.2kW instead of just 5kW?
I'm guessing that the orientation is East/West so the likelihood of you getting max panel kW is an odd exception anyway?

Cost difference, slightly in your favour by the look of it if you assume the existing inverter is low value.

SilverArt I ran two Gen1's on an East West spilt, no problems with cross charging.
It's only since moving to Gen2 inverters that this has started but hopefully wil be resolved officially with the new piece of hardware soon.

simondoyle Our Gen1 Inverter was upgraded from 3.6 to 5kW

Are you sure it's a gen1? My understanding is that the gen2 internals (specifically the busbars) are the same for HY3.6 and HY5 but different for the gen1s. I read on this forum that some installers had been able to change the firmware on a gen2 HY3.6 to make it 5kW, but there's also a statement from Givenergy saying that they don't do this and installers have had this ability removed. Or maybe that's the case in the UK, other areas maybe less strict?

Tim

Yes - it's definitely a Gen1 - I got into a row with the vendor about this, as they had promised me a Gen2 5kW and turned up with a Gen1 3.6kW!

They agreed at the time to swap it out for a Gen2 when they became available, but I only have a 5.2kW battery, so I might just leave it be...

To confirm it was Givenergy themselves who updated the unit remotely, at the vendor's request.

And yes, it's possible that this is not ordinarily done for the U.K. market owing to different inverter limit regulations.

simondoyle promised me a Gen2 5kW and turned up with a Gen1 3.6kW!

Yep, I'd be pretty hacked off if that had happened to me. I'll defer to @hoggy and @TheDragon (GivEnergy) to offer views on whether this is a not to be repeated modification, or if technically, it's feasible but damaging from a marketing perspective.

GE did pop their head up a few months back saying that although they used to do it (upgrade OTA) they won’t be anymore. I’ll try and find the post and link back. Think it was Adam Reynolds

Some interesting threads here. Looking at the data sheets for the 3.6 & 5.0 gen 2s shows very little difference in specs apart from the primary ac output 5k vs 3.6k and 22.8A vs 16A.

https://www.givenergy.co.uk/pdfs/products/datasheets/giv-hy-3-6-gen-2.pdf
https://www.givenergy.co.uk/pdfs/products/datasheets/giv-hy-5-0-gen-2.pdf

So, you can run more heavy duty appliances on the 5k box, less grid import. Always a good thing. And i can see that in the summer likley to be pushing more than 3.6 back to the grid. Hence the additional certifcation/permission from DNO. But, i see there is some discussion on having the 5k upgrade but then limiting the mains export to 3.6 to prevent the need for additional DNO permission. But, aside from restricting the output on the inverter (which is counter intuative as you want the 5k ac output) how else would you limit the grid export to 3.6 with a 5k output from the inverter - asking for a friend 😉

My idea at first was to use the 3.6k hybrid inverter for all the panels but the sales guy told me it would blow the inverter. I was hoping it would dump the power.

The idea of two inverter could save alot of money, less scaffolding and no rewiring of strings

danerf Interesting to see what your supplier's take is. It may be dependent on where about you are and who your DNO is

Ok, I've ran the numbers and to my surprise, it's more cost-effective buying the 9.5KW Battery and charging at the cheap overnight rate than getting 9 Solar Panels.
Are there any issues getting a 8.2KW Battery and 9.% KW Battery linked up together? If I was to charge them overnight, would each independently be able to charge at 2.6Kwp/h?

danerf If I was to charge them overnight, would each independently be able to charge at 2.6Kw

No.

From reading about solar installations and this forum, the common conclusion is that since solar panels are relatively cheap, if you don't maximise the number of panels you install initially, it's only a matter of time before you start thinking "I wish I'd installed more panels". More panels means that you can start harvesting earlier and continue to later in the day as the string voltage stays high for longer, and your harvesting season starts earlier in spring and finishes later in autumn. The major cost of panel installation is the scaffolding and manpower to do the work. It'll probably take as long to put up 21 panels as 12. I know you are have been quoted for an array on a different aspect, so that means more scaffolding but I wouldn't expect the cost to be much less (if at all) if you said not to bother with the other aspect.

Once you have maximised (within reason) your panels, then look to the best option for inverters. If you have two inverters and two batteries you will be able to charge each battery from PV or grid from its inverter at the maximum rate (2.5-3.6kW irrespective of the number of batteries). With one inverter and two batteries, you won't double the charge rate. With two inverters you also get the ability to supply house load from battery at 5 or 7kW (2 x 2.5-3.6). Obviously two inverters cost twice as much as one to buy but not twice as much to install.

danerf more cost-effective buying the 9.5KW Battery and charging at the cheap overnight rate than getting 9 Solar Panels

Do electricity tariffs change? This might be the case today but by the time the panels get to the end of their warranted life, usually 25 years, the energy supply tariff might be different. I'd advise to think about the long term, maximise your potential to be free from grid import for as long as you can in the year, if you can afford it. Maybe also consider how long you're going to be in the house for. For me, if it's your forever home, or at least ten years, it's a no-brainer.