Solar panels and battery - any real world reccomendations?

HungryHippos · 27 Oct 2022 at 12:56

I think that is pretty much the crux of it. Don't know if the V2 Givenergy can charge or discharge at more than 2.6KW.

I find for me the most important things are usually the first bits of it though, first few KW of panels are the most useful, first few KWH of the battery the most useful, and the same is true for charge/discharge.

You can't min/max fully on 2.6KW of draw like you can with the Solis, but the cost for the minor usage from the grid seems fairly negligible, and 2.6KW is usually a good enough speed for off-peak charging too.

Another factor might be support? Givenergy I think are a UK company who manufactures in China, but Solis may or may not just be Chinese, so your level of support could differ, although how much that matters I don't know.

Mercenary Keyboard Warrior · 27 Oct 2022 at 12:57

I would check the solis for DOD, if its 90% then I would go givenergy for the 9.5kwh being better than 10-1 (10% dod reserve)

Its easier to see a direct correlation between usable battery and savings now vs maybe something in rates that means GE is better in the future. (IMO)

Its not like any existing battery producer cannot change firmware to give more options anyway.

Freefaller · 27 Oct 2022 at 13:35

HungryHippos said:
I think that is pretty much the crux of it. Don't know if the V2 Givenergy can charge or discharge at more than 2.6KW.

I find for me the most important things are usually the first bits of it though, first few KW of panels are the most useful, first few KWH of the battery the most useful, and the same is true for charge/discharge.

You can't min/max fully on 2.6KW of draw like you can with the Solis, but the cost for the minor usage from the grid seems fairly negligible, and 2.6KW is usually a good enough speed for off-peak charging too.

Another factor might be support? Givenergy I think are a UK company who manufactures in China, but Solis may or may not just be Chinese, so your level of support could differ, although how much that matters I don't know.

And you have to remember that you're using the grid less, so you will be lowering your costs regardless.

I'm happy with the givenergy system, but I have no experience with any other.

94JDH · 27 Oct 2022 at 13:38

HungryHippos said:
I think that is pretty much the crux of it. Don't know if the V2 Givenergy can charge or discharge at more than 2.6KW.

I find for me the most important things are usually the first bits of it though, first few KW of panels are the most useful, first few KWH of the battery the most useful, and the same is true for charge/discharge.

You can't min/max fully on 2.6KW of draw like you can with the Solis, but the cost for the minor usage from the grid seems fairly negligible, and 2.6KW is usually a good enough speed for off-peak charging too.

Another factor might be support? Givenergy I think are a UK company who manufactures in China, but Solis may or may not just be Chinese, so your level of support could differ, although how much that matters I don't know.

Gen2 inverters charge and discharge at 3.6kW compared to Gen1 at 2.6kW

Zeeflyboy · 27 Oct 2022 at 13:42

Pure storage seems to be 90% DOD, so the givenergy technically has 0.5kwh more usable capacity… I had also been toying with adding an additional 5kw too as that would mean we could probably easily move every bit of extra consumption to off peak rates all year round.

While the PureStorage is a UK company, support for Solis had crossed my mind… I suppose worst case though replacing an inverter alone isn’t the worst thing and probably will have to happen over the life of the system anyway.

Decisions decisions…

Kill_Phil · 27 Oct 2022 at 13:42

94JDH said:
Gen2 inverters charge and discharge at 3.6kW compared to Gen1 at 2.6kW

Correct but as someone else said pretty much impossible to get hold of. Apparently a shipment is arriving in Jan but I'm not particularly hopeful, seeing as I've read some people ordered in June and keep getting pushed further and further back.

Tbf it's making me rethink. Have a sunsynk offer on the table but cant see too much in the way of reviews

94JDH · 27 Oct 2022 at 14:27

Kill_Phil said:
Correct but as someone else said pretty much impossible to get hold of. Apparently a shipment is arriving in Jan but I'm not particularly hopeful, seeing as I've read some people ordered in June and keep getting pushed further and further back.

Tbf it's making me rethink. Have a sunsynk offer on the table but cant see too much in the way of reviews

My installer has fitted two gen1 inverters and will retro fit when they are available which as you say is from around January. For reference I signed up back in March

SBo · 27 Oct 2022 at 14:38

S&SE have finally come back on my G99 application for 5KW maximum export on my 100amp supply, it starts "We have completed a network study and this has established that we do not need to carry out any reinforcement of our network to allow you to connect your generator."

OK great.

But then followed by:

"Final connection-Witness test £300.00
2nd comer contribution to prior work £319.05
VAT at standard rate (20%) £123.81"

So £742 for SSE to take a look at my already type approved inverter, and do nothing else.

My installer said he would "speak to them" having assured me six months ago that it would cost £0. I expect we'll go back with a G100 application instead as I can't see sense in paying that.

SSE are hardly helping the transition to net zero here are they...?

HungryHippos · 27 Oct 2022 at 14:47

That's weird, are you editing an existing install and they're checking it's compliant afterwards?

This was what mine said from SSE, so sounds similar.

Kill_Phil · 27 Oct 2022 at 15:17

94JDH said:
My installer has fitted two gen1 inverters and will retro fit when they are available which as you say is from around January. For reference I signed up back in March

Ahh blimey, doesn't fill me with much hope for securing one in Jan then as only placed my order a few weeks back. Will speak to installer if can look at gen1 as an interim but not sure I want to stump up a load of cash if only be a short term measure

OldKitMan · 27 Oct 2022 at 15:32

Zeeflyboy said:
Pure storage seems to be 90% DOD, so the givenergy technically has 0.5kwh more usable capacity… I had also been toying with adding an additional 5kw too as that would mean we could probably easily move every bit of extra consumption to off peak rates all year round.

While the PureStorage is a UK company, support for Solis had crossed my mind… I suppose worst case though replacing an inverter alone isn’t the worst thing and probably will have to happen over the life of the system anyway.

Decisions decisions…

Solis have a UK based support team as well. They are very busy at the moment but they do exist and they are helpful. FWIW Pylontech also have a UK based support team and they also seem very good.

Zeeflyboy · 27 Oct 2022 at 15:52

Thanks guys.

One last question - would you go for optimisers at least in the bottom string? Took a photo today at about 15:30 and you can see there’s some shading this time of year from next door which moves along the roof during the day.

Mercenary Keyboard Warrior · 27 Oct 2022 at 15:55

Do you know when in the year it starts to do that. IMO basing the decision on end of Oct when generation isn't going to be that great anyway would be a potential poor ROI

SBo · 27 Oct 2022 at 16:08

HungryHippos said:
That's weird, are you editing an existing install and they're checking it's compliant afterwards?

This was what mine said from SSE, so sounds similar.

Thank you for this, its the same letter just with a different bill! The surveyor is named on it so we'll query with him.

Hawk Tuah · 27 Oct 2022 at 16:51

Zeeflyboy said:
Thanks guys.

One last question - would you go for optimisers at least in the bottom string? Took a photo today at about 15:30 and you can see there’s some shading this time of year from next door which moves along the roof during the day.

Would optimizers be enough? That section of roof would be in shade almost all day. Even a row at the top would be partially shaded, and it's only October.

katie279 · 27 Oct 2022 at 21:57

Ooh, just had our Eddi fitted by surprise today - is there anything I need to do/should do to optimise or just leave it as is?

Freefaller · 27 Oct 2022 at 22:04

katie279 said:
Ooh, just had our Eddi fitted by surprise today - is there anything I need to do/should do to optimise or just leave it as is?

I just left it on auto... they should have set it up to work as it should. The only thing I've read is to select "avoid drain" so that it doesn't draw from the battery as long as there is surplus energy but not sure if it's worth it or not.

Ron-ski · 27 Oct 2022 at 22:25

Just noticed this on https://www.itstechnologies.shop/pages/order-status

Givenergy

Gen2 Hybrids: We have recently discovered that Givenergy or Givenergy’s exclusive distributor have decided not to supply any re-sellers with Gen2’s to re-sellers until sometime next year and have even changed over all orders without prior consent to Gen1 hybrids. We are now having to contact all customers for Gen2 to explain the situation and offer either Gen1’s or a refund.

katie279 · 27 Oct 2022 at 22:26

Freefaller said:
I just left it on auto... they should have set it up to work as it should. The only thing I've read is to select "avoid drain" so that it doesn't draw from the battery as long as there is surplus energy but not sure if it's worth it or not.

Perfect - ok, will have a fiddle tomorrow!

Not sure how long it'll be before I can actually check it's working given current weather!

gpuerrilla · 27 Oct 2022 at 22:27

katie279 said:
Not sure how long it'll be before I can actually check it's working given current weather!

You mean its not so sunny Scotland now? :confused: