More expensive as the battery is 6.5kwh compared to the original 4.9kwh originally quoted for. No idea what the model number is for either battery or inverter as I’ve yet to go back to the installer. I‘m canvassing opinions on the brand first before I do anything. Seems the battery is a LiPo (I think the term is) which is a good thing from what I’ve read
Solar panels and battery - any real world reccomendations?
- Thread starter GinG
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Soldato
All the house batteries are LiFePo4 basically. The only real significant difference between them all is the BMS implementation and the controlling software. Plus the for most minor thing of IP ratings etc, a few cannot be used outside.
Soldato
It's so sunny today, I think my panels have gone into shock. 
Soldato
4.86 kwh today, can deal with that, that much tends to be enough for a fairly average day between GO charges.
Soldato
Totally agree mate.
Similar to @Bluecube I had an email from my installer saying can't get / having problems getting givEnergy inverters and battery. They're offering a GroWatt SPH3600 + battery instead (a bit pricier it seems) Either a 6.5kWh (GBLI6532) or 3x 3.3kWh. (ML33rta) It's an extra £1000 for the 9.9 or £1000 less for the 6.5. I'd go with 2x 6.5 if the markup wasn't a bit silly and 1 isn't really going to cut it over winter (12-15kWh/day) My issue with the 3.3 x 3 is the draw seems really poor on paper with a rated discharge power of 1.64 KW. Anyone got any real world experience with the groWatt kit?
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Soldato
My GivEnergy G1 system can only charge/discharge at 2.6KW but that seems OK. It rarely gets above that, and if it does it's mainly if I use heavy duty stuff like the oven or boiling water with kettle.
With the sun shining it's a non-issue really, as it can combine the solar and the battery to allow for the house to use around the 5KW if there is enough sun going on. At night it's back to the 2.6KW limitation.
As long as I'm a little careful about things grid draw is still pretty limited, but it's just me so it's easier to co-ordinate things to not overlap too much usage at once.
At 1.64KW I'd find that a little limiting, especially if that is the max charge rate as well. I'd certainly be taking from the grid more than I'd like, and charging up off-peak would be too slow. At 2.6KW I can theoretically charge about 10KWH in the 4 hour GO window. At 1.64KW I would be unable to fill my 8.2KWH battery in that same time window.
Not sure what alternatives options you have though?
With the sun shining it's a non-issue really, as it can combine the solar and the battery to allow for the house to use around the 5KW if there is enough sun going on. At night it's back to the 2.6KW limitation.
As long as I'm a little careful about things grid draw is still pretty limited, but it's just me so it's easier to co-ordinate things to not overlap too much usage at once.
At 1.64KW I'd find that a little limiting, especially if that is the max charge rate as well. I'd certainly be taking from the grid more than I'd like, and charging up off-peak would be too slow. At 2.6KW I can theoretically charge about 10KWH in the 4 hour GO window. At 1.64KW I would be unable to fill my 8.2KWH battery in that same time window.
Not sure what alternatives options you have though?
Soldato
0.5c and it will be per battery. The inverter is higher rated then that.
Edit: I'd be asking for the GroWatt SPH5000 though
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I'd forgotten to check the charge rate, I just moved to Octopus in anticipation, you're right, they won't charge in 4 hours at 1.6kW!
I could wait it out or shift installer I guess, but that's another x months for a site visit and 3 months for install vs 6 weeks if I agree to groWatt.
Nothing against it in principal but yes, the ML33 looks to be 32A/42.5A charge/discharge @ 51V. I'd have thought they'd install in parallel and the discharge rate would increase (like the Huawei's) but my installer says not so I guess I'm trying to calculate how often I go over a 1.6kW draw vs having the extra 4kW. Neither seems a good compromise. 2x 6.5 is what I'd want but it's 2.5K more than the givEnergy gen2 9kWh with a worse depth of discharge and 6000 cycle lifespan vs unlimited.
I could wait it out or shift installer I guess, but that's another x months for a site visit and 3 months for install vs 6 weeks if I agree to groWatt.
Nothing against it in principal but yes, the ML33 looks to be 32A/42.5A charge/discharge @ 51V. I'd have thought they'd install in parallel and the discharge rate would increase (like the Huawei's) but my installer says not so I guess I'm trying to calculate how often I go over a 1.6kW draw vs having the extra 4kW. Neither seems a good compromise. 2x 6.5 is what I'd want but it's 2.5K more than the givEnergy gen2 9kWh with a worse depth of discharge and 6000 cycle lifespan vs unlimited.
My installer seems to be a bit 'this is what we can get' and I think the answer to the 5000 would be not without a DNO and they seem reluctant / it probably won't be done in 6 weeks for install but yes, I'd much rather have a system than can cope with a 5kW peak, especially if the cost difference is minimal.
Soldato
You can export limit the inverter but have a slightly bigger one for internal use.
Nice benefit there is future proof slightly in case the default limit is changed as well, that 3.6KW default limit they set may go up some day.
Nice benefit there is future proof slightly in case the default limit is changed as well, that 3.6KW default limit they set may go up some day.
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Soldato
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Is RB Grant your installer?
Soldato
The installer is reluctant to apply to the DNO for a G99? It's the kind of installer I'd avoid if they can't be bothered to do an hours work, and e-mail a form to the DNO. These half baked installs that are supposed to last 20+ years, but if/when running an almost full electric household simply won't be suitable for the most part.
Anyhow, you'll be fine with the Growatt's x3 that are in parallel as they can each charge at a maximum rate of ~1.6kW, so a total of almost 5kW which is more than the 3.68kW inverter could delivery anyhow. I would really push for the 5kW inverter so you can run more amps outwards, for when you have heavy demand, which is easy to hit for short periods of times.
Man of Honour
Nice! I think I had about 5.7 and jumped on to put the washing machine and dishwasher on!
We've become quite neurotic about it! Haha!
I'll see if I can convince them, it looks like it's an extra £100 for the bigger inverter. I'll ask groWatt about the batteries though I've had a reply on a user forum from someone with 3 ML33rta's saying they can pull 3kW from them no problem so looks like journey is right.
Same as you then?
Soldato
Nice! I think I had about 5.7 and jumped on to put the washing machine and dishwasher on!
We've become quite neurotic about it! Haha!
Yep I try and use as much of my generation as I can
Makes more sense to me as well, 1.6KW would be very low.
Yep. I’d give them the go ahead but I’m not sure if I’d get my EST loan which is based on the original quote