those controls sound like they'd drive my wife crazy. You'd think they'd try and design simple ones rather than squashing too many functions into not enough buttons. I have one socket for the oven but a big red switch and a 32A fuse so I assume there is a line they can tap into for the hob and I could have both on that.
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Solar Panels UK - is it worth it?
- Thread starter jdwuk
- Start date
Pete UK
Member
If it helps;
That’s almost exactly 75% of what I’m paying, for almost exactly 75% of the panels and battery storage. In almost exactly the same places on the roof probably, South, East and North.
Ours is on 3 different roofs, 3 and 2 stories up.
So I guess that’s about the going rate.
Drew57
Active ember
We fitted this white induction hob into a white marble worktop back in February 2019 and have been very happy with it. Most of the time using a medium-high setting it draws below the 3.6kWh inverter limit (as long as other high usage appliances are not used concurrently).
Against the white marble it contrasts as light greyish-white but is still far more attractive than black. It is completely flat with a shallow silver edging and wipes-clean very easily.
IT646KR
Against the white marble it contrasts as light greyish-white but is still far more attractive than black. It is completely flat with a shallow silver edging and wipes-clean very easily.
IT646KR
Pete UK
Member
…Also, yeah the output would be 2x3.6 kW for the Gen 2 inverters plus an extra 1.4 each from the Solar if the sun is shining.
I thought the older Gen 1’s were 2.6kW + the Solar. But I could be mistaken.
In case you’re not aware, there is a gen3 hybrid 5.0 inverter out now, the spec looks the same from what I can see except that it hides the ugly cable connections underneath. Not sure if that’s worth the extra money or not. Unless you’re looking at it all day, or there is some other advantage I didn’t notice.
I thought the older Gen 1’s were 2.6kW + the Solar. But I could be mistaken.
In case you’re not aware, there is a gen3 hybrid 5.0 inverter out now, the spec looks the same from what I can see except that it hides the ugly cable connections underneath. Not sure if that’s worth the extra money or not. Unless you’re looking at it all day, or there is some other advantage I didn’t notice.
WannabeOwner
Well-Known Member
The controls are fine for "Turn hob on. Turn on Ring #1 and set to 0...10"
Also not too bad for "Set timer on Ring #1 for 5 minutes" - e.g. if you put an egg to boil and then the phone rings ... but good luck if you accidentally press the Child Lock and are trying to figure out how to reverse that (ask a child is probably your best bet!!)
Basically: I would choose brand largely on usability of its interface.
Can't find an online manual for mine, but here's a different model. It would drive be BERSERK
Press a button to choose which ring and then have to hold-down a (separate) button to go up/down the power numbers. What a huge waste of time. At least on mine each ring has a set of digits 0...10 and you just click on the one you want.
Only difference between gen2 and gen3, technically,is solar input up to 15A from 13A (gen1 11A).
I have asked the company as we definitely need to be able to sustain more than 7KW at one time for the battery solution to be viable for us and to allow us to charge the batteries on the low night rate and then to be able to use solar and battery to power everything during the day (and on dark winter days that means really everything on battery)
Awaiting a reply from the company
What you would normally have is a spur from that socket and then one of these https://www.bes.co.uk/dual-cooker-appliance-outlet-plate-45a-white-22070/
It might be that you already have at least a single output one and will live bellow the countertop level often in the proximity of that socket.
If you're using Givenergy and dependent on 7kWh from the batteries only, you'll need multiple inverters and batteries.
The 3.6W and 5kW inverters, either gen2 or gen3, each discharge maximum of 3.6kWh from batteries only. If you need that rate continuously, and have two inverters and only two 9.5kWh batteries they'll empty in less than 3 hours.
7KW is what I hope to be a maximum draw from the batteries.
Over the course of the entire day I expect to use approx 28KwH.
I think they are planning on giving me 2 hybrid inverters... but the datasheet seems to suggest the maximum battery only output is 2.6KW
Whilst I think I will only very rarely go over 7KW draw of power (in which case I guess we would dip into the grid) I would expect to go over 5.2KW quite frequently.
So I think I need to wait for them to come back to me in answer to my question.
One other thought: will I have any issues filing up from zero charge 3 x 9.5KWH GivEnergy batteries during the cheap night tariff? As if so, that would also be a concern and would impact my financial analysis.
Also in relation to charging, if you're on Octopus intelligent for example, you'd only be able to charge two batteries per inverter in the 6 hour cheap window.
Must have posted and missed your additional one in the process!
If the the output is showing as 2.6kW then that is a Gen 1 hybrid inverter ( max actual charge is around 2.48kW with these). They've been recently available "free" with battery purchases from certain wholesalers.
You definitely need Gen2 or Gen3 hybrid inverters with the 3.6kW charge/discharge rate.
As my previous post a 6 hour window will give you enough to charge two batteries on one inverter.
There are also still issues with cross charging on multiple hybrid inverters, where one battery empties and fills the other and visa versa. This will be resolved with an official EMS unit to control it when it's released!
It can be resolved very well unofficially using GivTCP - plenty of help and files on a Facebook group for this.
I'd personally look at a battery per inverter (19kWh total) and see how you go - you can always add more later.
if the batteries charge at 3kw max (I think the 9.5s are) then you should be able to fill one almost in a 3 hour window. So regular octopus go with a 4 hour window would manage one battery (per inverter) but not two. Can run two inverters in parallel if your other house load is ok - so 14kw. Octopus intelligent has a 6hr window so you could just about fill two batteries on one inverter at 3kw but not 0-100% - but they reserve 4% anyway (despite saying 100% DoD, I don't understand that part)
Assume for your math you need 3hrs to fully charge one battery on one inverter.
phil4
Member
You'll need to be careful with the DNO restrictions, which might hobble you a bit. ie. if you fit 7kW of inverters you'd need DNO permission on G99 for that export. Your other option is size your solar and inverter for the DNO restriction, eg. 5kW for both, and then use an AC connected battery, so has nothing to do with the inverter and is not limited by it.
Expensive option, but this is what I'm doing, with a 5kW solar inverted (DNO limit is 6kW), but 2 x Tesla Powerwalls, which will do 10kW in total. DNO doesn't care as they're not part of the solar, they're AC, and they'll be set to not export.
So as others have mentioned, Gen1 is good for 2.6kw battery charge / discharge, Gen2 3.6kw.
The batteries can be attached to exactly 1 Hybrid inverter. That means 1 inverter with 1 battery and a 2.75hr charge period, and 1 inverter with 2 batteries and a less favourable 5.5hr charge time. If you have IO then you'll just fit in, but that's another pain because you've then got to work out how you avoid the batteries discharging to charge your car. Go faster is going away, so it's 4hr go windows as the most convenient option..
The other thing to mention is that GivEnergy don't really support two hybrid inverters on the same supply phase. They tend to "trip over" each other, one detects a net load (export to grid) when a kettle turns on, so outputs from the battery. The kettle turns off and the other inverter detects an export to grid, and starts to pull power. They basically end up cross-charging, which is a good way to increase the cycles on the battery and waste 20% of the energy.
They say it's only supported with an external management system, which can totally be done, but isn't something they support right now.
The GivEnergy stuff is reasonably good, but it does less well with complex usecases. (They do have powerwall clones coming, which supposedly support up to 6 units with sync. Might fit the bill, but I'd probably want to see happy users with them before I spent my money)
The other thing is I'm not sure if you can island in EPS from two different hybrid inverters.
For the amount of storage you're looking for, I'd probably be more inclined to look at a pair of powerwalls, which will give you roughly the same capacity. Tesla have done a good job with enabling that usecase and making it pretty seamless. You also won't have issues with overnight charging not fitting within the off-peak window
Last edited:
That is interesting you mention that... a different company (WarmaUK) has come up with two possible solutions:
GivEnergy
On the GivEnergy system, we have three 3kW inverters each linked up with 3 x 9.5kW of storage (28.5 in total)...and allowing 9KW of power output at once
SolaX X1-3.6T 1ph (inc WiFi dongle) Dual MPPT inverter (inc DC and WiFi)
Giv.AC 3.0 Ac Coupled
Inverter Gen2 GivEnergy 9.5kWh LiFePO4 Battery (integrated DC breaker)
SolaX
On the Solax system, we have two 7.5kw inverters each linked up with 17.4kW of storage (34.8KW in total).... and allowing 15KW of power output at once
SolaX X1-3.6T 1ph (inc WiFi dongle) Dual MPPT inverter (inc DC and WiFi)
SolaX X1 G4 7.5 FIT AC Solax AC retroft charging solution for Triple Power batteries
SolaX Triple 5.8kWh LFP Battery Triple Power High Voltage Batteries for SolaX systems
Both systems are priced around the £22k mark (SolaX being slightly more expensive). I also understand that the SolaX system has usable storage of approx. 31.2KW... so that is an advantage as in Winter we can use 33-36KwH per day.
As mentioned earlier in this post, my primary objectives are financial and to allow me to use cheap overnight tariffs (such as Intelligent Octopus) to fully charge the batteries overnight, and then use them (and solar if there is any available) to run my entire house without dipping into the grid during the peak rates.
I am not sure if DNOs would be required in either / both of the above scenarios.
I am also trying to find out if the above system can be set up in "islanding" mode so that - if there would be a power cut - we could still operate normally for as long as there is battery power.
I have to say that, although I consider myself quite intelligent, this is way outside my skillset / knowledge - so quite nervous !
The batteries will charge at 3.6kW with the Gen2/3 hybrid inverters, the AC inverter limits this to 3kW.
With Go, you only would fill 1.5 x 9.5kWh batteries, which is why I went with one battery per inverter for now.
DNO approval will be needed for anything larger than 16a output. For single phase, that means a 3.6kw inverter, which probably means about a 4kw array if you don't want excessive clipping.
So the DNO will certainly need to be involved in any of the scenarios you've mentioned.
My 2c is that you're asking domestic installers about a fairly specific and complex solution with a lot of requirements, and they're positioning standard domestic solutions and just installing multiple units - I don't think this will work awfully well unless you put work into GivTCP and soforth.
For storage, powerwall is your plug and play option, where multiple units would be far from unusual. Then just have standard inverters
One further though, you'd spending a *lot* of money here to meet peak energy requirements. I would spend some time working out if you can spread loads so that the peaks are flattened a little. And also remember that you still have the grid there, and if you can cover 5 of a 8kw load for 10 minutes a day, well, that's going to cover the majority of the costs
Last edited:
