Being a new build it's probably only a token system, so if you have more space on the roof, regardless of what way it faces, it may be worth getting additional panels fitted as well as the battery.
Solar panels and battery - any real world recommendations?
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Being a new build it's probably only a token system, so if you have more space on the roof, regardless of what way it faces, it may be worth getting additional panels fitted as well as the battery.
Anker Solix is available in the U.K. IIRC.
Tesla power wall is overkill for what you need and I doubt it would make sense financially. 13.5kwh is probably 40% larger than you actually need.
The returns from battery storage doesn’t scale, once you have enough, paying extra for more negatively impacts the financial benefit.
If you do get one of these all in one systems which have a solar input, you’ll be able to extend your solar down to them and cut out the inverter in the loft, that’s how I’d do it anyway.
I'm basing that figure from our last house. I'm struggling to work out exactly what we use a month in this house as it's been a pretty sunny few months since we moved in so I expect we'll have a better idea of our actual use over the winter.
We are also planning on getting a split air-conditioning system for the bedrooms and living room so I expect that will also increase how much energy we use in the warmer months. Would like to get something that can accommodate for that as well as our usage at the moment
Definitely don't want to spend money for the sake of just spending money though. That's why I thought the modular nature of the Anker ones were quite appealing
We are also planning on getting a split air-conditioning system for the bedrooms and living room so I expect that will also increase how much energy we use in the warmer months. Would like to get something that can accommodate for that as well as our usage at the moment
Definitely don't want to spend money for the sake of just spending money though. That's why I thought the modular nature of the Anker ones were quite appealing
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Isn't exporting to grid much more of a pain if its not MCS certified though?
No because MCS isn't the only cowboy /sarc/ in town
Soldato
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Install all done and dusted yesterday, already have the MCS certificate and they have sorted the switch to the new tariff, quite happy with the whole process and would recommend contact solar to anyone
Getting paid is more of a faff from what ive seen yes. But that has nothing to do with your house insurance.
Update!
My install is due next week. I just got a notification from UK Power networks that I have an export capacity of 10kW so I think that's OK?
Reef et al. were right. The 12kw batteries don't work with the inverter. The installer has suggested going for an extra 10kw unit instead. The additional cost for the battery would be £2k.
That would make the system out to be:
Based off my usage, I'm tempted to go for the extra battery. As I have a heat pump I'll be hammering it in the winter months and think I'll appreciate the ability to charge the batteries overnight at 7p on decent tariff. Do you think that's a reasonable decision or does it take so long to recoup the extra cost that it's just not worth it? Getting the extra battery now will probably save around £800 over getting it later. Or just go with 2 batteries and optimise in the way that b0rn2sk8 suggests?
My install is due next week. I just got a notification from UK Power networks that I have an export capacity of 10kW so I think that's OK?
Reef et al. were right. The 12kw batteries don't work with the inverter. The installer has suggested going for an extra 10kw unit instead. The additional cost for the battery would be £2k.
That would make the system out to be:
- 26 Aiko panels over 3 different roofs
- 12kW Sigenstor Inverter
- 3x Sigenergy 10kWh batteries
- Sigen EV AC Charger 7 kW 4G
- Bird proofing etc. etc.
- £17k
Based off my usage, I'm tempted to go for the extra battery. As I have a heat pump I'll be hammering it in the winter months and think I'll appreciate the ability to charge the batteries overnight at 7p on decent tariff. Do you think that's a reasonable decision or does it take so long to recoup the extra cost that it's just not worth it? Getting the extra battery now will probably save around £800 over getting it later. Or just go with 2 batteries and optimise in the way that b0rn2sk8 suggests?
That's actually a really good export limit. I'm waiting for my G99 (still) and doubt ill get much more than about half that. The £17k for all of that is a good deal too.Update!
My install is due next week. I just got a notification from UK Power networks that I have an export capacity of 10kW so I think that's OK?
Reef et al. were right. The 12kw batteries don't work with the inverter. The installer has suggested going for an extra 10kw unit instead. The additional cost for the battery would be £2k.
That would make the system out to be:
- 26 Aiko panels over 3 different roofs
- 12kW Sigenstor Inverter
- 3x Sigenergy 10kWh batteries
- Sigen EV AC Charger 7 kW 4G
- Bird proofing etc. etc.
- £17k
Based off my usage, I'm tempted to go for the extra battery. As I have a heat pump I'll be hammering it in the winter months and think I'll appreciate the ability to charge the batteries overnight at 7p on decent tariff. Do you think that's a reasonable decision or does it take so long to recoup the extra cost that it's just not worth it? Getting the extra battery now will probably save around £800 over getting it later. Or just go with 2 batteries and optimise in the way that b0rn2sk8 suggests?
Your usage averages over 41kWh per day in the November - February period there and three of the 10.0 batteries is 26.28kWh usable - a figure which even your lowest usage days in Dec - Feb usually surpass. In that case I would probably go for it. It's likely you'll get good use of the extra battery. It will also allow the maximum charge / discharge rate of 12kW, as each battery can do 4.6kW.
I'm currently going for two of the 10.0s with the 12kW inverter, but will also change to three if I get a terrible export limit. Like you I have a heat pump, but it will be our first winter with it so we have no idea on usage at the moment. I'm also on Octopus EV tariff with a 6p/kWh cheap rate, so the sums look stronger as peak units are 27.5p/kWh, meaning 21.5p/kWh for every unit saved.
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@reef, IMO its not quite that straightforward.
You need to factor in they also has >12kw of solar so they will be generating a lot even in winter. Likewise I assume those daily usage numbers also include EV charging so 'house' usage is going to be a lot lower. There is also the overnight house use and you can 'pre heat' your house with cheap rate electrcity and then coast the rest of the day running your heating slightly below the heat loss. You'll use more energy but its cheaper.
My average daily usage in Jan was 35kwh (1107 for the month) with 79kwh being the high and 19.7kwh being the low. I only generated 141kwh as I have zero south facing pannel despite having 23 of them.
My battery is 13.5kwh usabe battery and I had 18 days where I used a material amount of peak rate electrcity. However, I have done the math and if all of that electrcity was at the peak rate instead of the peak rate, I would have saved just £32.61 and this is the worst month for usage. My savings in December and Feb would be around £10, so you are talking about saving £50-60/year in peak rate electricity.
Now factor in charging the battery from the grid at 7p and selling it back to the grid at 15p, you'll make 72p a day doing that (assuming 9kwh usable module and factoring in no losses), thats £194/year (9 months worth).
You'll see where I am going with this now - we have made £194 from brown export plus a generious £60/year saving from 3 months peak electricity total benefit per year is £250. A module is £3k plus fitting and installer margin, call it £3250 as its being installed at the same time as the rest of the system, you'd be breaking even in 13 years. I'd say that is being fairly optermistic also.
In my use case it might just pay back in its useful life but you really ringing every ounce of performance out of it to even make the man maths work. If export rates drop, the overnight rate went up, or brown export went away, I'd be screwed on the pack back. I've not factored in inverter losses into the above for the brown export either.
You need to factor in they also has >12kw of solar so they will be generating a lot even in winter. Likewise I assume those daily usage numbers also include EV charging so 'house' usage is going to be a lot lower. There is also the overnight house use and you can 'pre heat' your house with cheap rate electrcity and then coast the rest of the day running your heating slightly below the heat loss. You'll use more energy but its cheaper.
My average daily usage in Jan was 35kwh (1107 for the month) with 79kwh being the high and 19.7kwh being the low. I only generated 141kwh as I have zero south facing pannel despite having 23 of them.
My battery is 13.5kwh usabe battery and I had 18 days where I used a material amount of peak rate electrcity. However, I have done the math and if all of that electrcity was at the peak rate instead of the peak rate, I would have saved just £32.61 and this is the worst month for usage. My savings in December and Feb would be around £10, so you are talking about saving £50-60/year in peak rate electricity.
Now factor in charging the battery from the grid at 7p and selling it back to the grid at 15p, you'll make 72p a day doing that (assuming 9kwh usable module and factoring in no losses), thats £194/year (9 months worth).
You'll see where I am going with this now - we have made £194 from brown export plus a generious £60/year saving from 3 months peak electricity total benefit per year is £250. A module is £3k plus fitting and installer margin, call it £3250 as its being installed at the same time as the rest of the system, you'd be breaking even in 13 years. I'd say that is being fairly optermistic also.
In my use case it might just pay back in its useful life but you really ringing every ounce of performance out of it to even make the man maths work. If export rates drop, the overnight rate went up, or brown export went away, I'd be screwed on the pack back. I've not factored in inverter losses into the above for the brown export either.
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Different tariffs are likely to be much more expensive due to the EV.
That's why you need to model - not guess!
I think there is one thing we can be certain of, installing another battery module after the fact proponent be cost effective due to the additional £800 cost.
@Marakith I don’t think you’ll be disappointed either way but you’ll need to do the work.
The ‘safe’ option would be to get the 3rd module but it ultimately could cost you a bit more in the long run. That’s ultimately the decision at hand.
@Marakith I don’t think you’ll be disappointed either way but you’ll need to do the work.
The ‘safe’ option would be to get the 3rd module but it ultimately could cost you a bit more in the long run. That’s ultimately the decision at hand.
@dmsims What system do you have, and would recommend?
Yes, Sigenergy is is young company, and there are risks associated with that, and I've no idea how well it would work without the cloud, but the same applies to an awful lot of things - we only have to look at Fisker to see what can happen.
Yes, Sigenergy is is young company, and there are risks associated with that, and I've no idea how well it would work without the cloud, but the same applies to an awful lot of things - we only have to look at Fisker to see what can happen.
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I would avoid anything with proprietary connectors, cloud based and that is difficult to diagnose but that's just me!
Putting that into practice and taking batteries as an example I would want to see a "normal" lug connector, a BMS that supports multiple inverter manufacturers, and is user serviceable at the cell level
A sensible approach for those that can manage a system like, the vast majority of mainstream systems, which installers install don't really fit into that category though do they?
You never said what system you have?
Installers do what is easy (profitable) for them (mostly). From an installers perspective Sigenergy is a great system and there are some nice sweeteners.
Mine is Victron