Soldato
Tell em you can't afford it but would they entertain wiring them in if you effectively install them on the roof ready for them? Surely that can't take them a lot of time if the cabling is sat there waiting to be attached
Solar panels and battery - any real world reccomendations?
- Thread starter GinG
- Start date
Tell em you can't afford it but would they entertain wiring them in if you effectively install them on the roof ready for them? Surely that can't take them a lot of time if the cabling is sat there waiting to be attached
Soldato
Only this morning I was reading an article comparing induction hobs and slow cookers, the induction hob was far cheaper. We currently cook from gas, but will be changing to an induction hob, in fact the electrician will be installing the power supply for it next week.
Yes my garage is at the back / side of the house, it's got a flat roof unfortunately, but I could do a "ronski" and get some brackets done. Could fit at least 6 panels there... dammit don't tempt me
Go on, you know you want to. If the roof is strong enough you can use a ballast system which is easy and means no holes in the roof.
Soldato
Have a read of the instruction manual, I bet it's just a case of plugging it in. Only potential issue is with warranty if there is ever a problem.
Soldato
Yup this as well.
Soldato
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- 1 Oct 2006
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That would be a dick move if they have, but as with all of these things if you've got physical access to it then it'll be hackable.
Soldato
Thanks for your reply.
I know I'm going to sound thick but how would I determine what our baseline would be?
I can work out our average daily, no problem. Am I using Only electricity consumption?
01/09/21 to 16/02/23 average daily electricity is 10.13 kwh with an average cost of £3.90 (gas is 48.16 kwh with an average cost of £5.20)
Does a household use extra electricity when it's cold?
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Soldato
Cold tends to align with dark
So more lights, central heating pump, more inclination to hot meals
I assume and it seems to work out for me that I use about 5% less in summer months and 5% more in winter months when compared to my average
Soldato
Ah sorry I may have got wires crossed, you mentioned electricity only for supply but you must have been talking about business rather than home?
A bit more electric in winter yes, but if gas does heating, then not loads more! If you had electric heating then yep, would be a lot more.
10 kWh is a good place to be and I think where Solar can really start to shine.
You want reasonably to generate what you use in a year, 1 kW of panels well positioned should be capable of around 1000 kWh per year.
Your usage is 10 kWh per day, so 3650 kWh and change per year. Ideally you'd want at least a 3.6kWp system but you may as well go a bit bigger if you can.
There are fixed costs to installations, adding some extra panels can help with Winter generation, and also just give you more options later. I'd oversize rather than under-size personally. If I could have added some more panels easily I would have done
For battery, you reasonably want enough to keep your power going overnight, most of the time. I think somewhere around 60%+ of your daily usage is good. But if say a 10kWh battery was possible at a reasonable price, you kind of may as well get that.
Battery isn't just for pure generation and usage purposes, sun can cut in and out a lot, it smooths out your grid usage a bit even on a sunny day, because if the sun dips behind a cloud whilst your oven is on, the battery will take over powering it rather than resorting to grid.
Additionally I would say that orientation matters a bit, as does shading factors. E tends to get sun earlier, S is the best overall, and W gets it later. N is awful, don't put panels N facing. E and W are about 80% of the generation of S. Splitting across more than one orientation can be good, gives you more generation slower in the day, rather than all at once when you can't use it as easily.
For shading, if you get a lot, you may need optimisers, Solar Edge are well regarded.
MKW has this, but you can also get hot water diverter if you have a tank, it can send excess solar to the tank to heat your hot water. I cant' do this, Combi boiler only :9
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Yeh, I’d fit as many panels as you can in first instance and worry about batteries if you have any money left.
A huge chunk of the cost is the installation, think scaffolding and labour. It doesn’t really cost less on the installation side if you lower the number of panels you get. You are paying for the scaffold and labour for the whole day if you get 9 or 12 panels and the marginal cost to add a panel is small.
The more panels you get, the better your winter generation will be. In summer you’ll produce more than you can use on a sensibly sized domestic system.
A huge chunk of the cost is the installation, think scaffolding and labour. It doesn’t really cost less on the installation side if you lower the number of panels you get. You are paying for the scaffold and labour for the whole day if you get 9 or 12 panels and the marginal cost to add a panel is small.
The more panels you get, the better your winter generation will be. In summer you’ll produce more than you can use on a sensibly sized domestic system.
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Soldato
Soldato
Personally if I was serious about batteries but not on day 1 I would just get a hybrid inverter fitted with the panels.
The costs are not that much more. Certainly cheaper than having two inverters one for panels and one for batterie(s)
The costs are not that much more. Certainly cheaper than having two inverters one for panels and one for batterie(s)
Soldato
Also simpler, adding an AC battery would require G99 application.
Glad I've gone for two inverters with a battery on each, as I would be able to charge 19kWh in that period.
However my daily usage is high with the EV as well, so currently Go seems a keeper until I run the numbers.
Soldato
MKW ran some numbers and Go is generally better anyway.
If you export a lot, then that changes a bit, but a lot of us using this don't export much.
Go does benefit from some min-maxing in not fully charging the batteries ready for a good day though, it's a little risky if Solcast winds up being way off.
Soldato
You'll export a whole lot more as we head towards summer.
One thing with Flux is if you can fully charge the batteries during the three hours, then any solar production over and above what you use at other times is exported at higher than what you paid, which takes a bit of guess work out of it.
Then export as much as you can in the peak period, even if you have to import some afterwards its less than what you got paid to export.
One thing with Flux is if you can fully charge the batteries during the three hours, then any solar production over and above what you use at other times is exported at higher than what you paid, which takes a bit of guess work out of it.
Then export as much as you can in the peak period, even if you have to import some afterwards its less than what you got paid to export.
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Soldato
The ez life version is tempting not going to lie. Every time I look at this the prices change! I can even see my own screenshot the other day had export at 36p odd, and now it's showing 38p odd, this is for the same region both times.
I don't think I'd be exporting much until May ish, and I can see from my history that export in September was low, so it's whatever it does in the intervening gap.
The bigger problem is what to do after the September or so even if I went to it, the 3 hours isn't long enough to charge me up beyond about 80% in Winter, and I may struggle to get back onto Go easily. My 7.5p/40p rate runs until 01/09.
I don't think I'd be exporting much until May ish, and I can see from my history that export in September was low, so it's whatever it does in the intervening gap.
The bigger problem is what to do after the September or so even if I went to it, the 3 hours isn't long enough to charge me up beyond about 80% in Winter, and I may struggle to get back onto Go easily. My 7.5p/40p rate runs until 01/09.
Yes I thought that might be the case, I'm likely to use a lot of my generation hopefully anyway so export will be minimal
3 panels on a string might not be create enough voltage to fire up the inverter, in general a minimum of 4 panels?
Soldato
IMO Octopus have been very clever with the charging and exporting prices.
Once you factor in a reasonable allowance for energy losses there is practically no point exporting at the 4pm-7pm rate and paying for grid useage in the normal day rate period
And likewise in the flux charging to day rate export window, again its nigh on the sorts of difference/loss you would expect to see from the battery losses and inverter discharge.
So your only real "win" is charging in the flux period and discharging in the peak rate period. Which means just sitting there on that battery charge (or most of it) all day paying for day units when your not generating enough or the sun is down, waiting to get to 4pm in order to discharge.
But if you take go, you can buy in at 12p, your using 12p units.
The flux scheme clearly suits those with very high generation potential or those with no batteries who would have been buying at 34p and exporting at max 15p
The flux scheme comes out nearly as good as go. Go is an incredibly cheap tariff for what it is.
So flux is great, its a really good benefit for solar users and a long time coming. And if your not on go, and I suspect thats going to be harder to get onto over time, its almost as good and you have no worries on being on it.
Once you factor in a reasonable allowance for energy losses there is practically no point exporting at the 4pm-7pm rate and paying for grid useage in the normal day rate period
And likewise in the flux charging to day rate export window, again its nigh on the sorts of difference/loss you would expect to see from the battery losses and inverter discharge.
So your only real "win" is charging in the flux period and discharging in the peak rate period. Which means just sitting there on that battery charge (or most of it) all day paying for day units when your not generating enough or the sun is down, waiting to get to 4pm in order to discharge.
But if you take go, you can buy in at 12p, your using 12p units.
The flux scheme clearly suits those with very high generation potential or those with no batteries who would have been buying at 34p and exporting at max 15p
The flux scheme comes out nearly as good as go. Go is an incredibly cheap tariff for what it is.
So flux is great, its a really good benefit for solar users and a long time coming. And if your not on go, and I suspect thats going to be harder to get onto over time, its almost as good and you have no worries on being on it.
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Soldato
Yep so the dilemma is leaving Go for a slightly better profit in summer, may also mean I can't get back onto Go for the winter.
That would certainly wind up costing more longer term because it's by far the best Winter plan.
Decisions, decisions.
Also not impossible they start asking for proof on renewal and then I can't anyway.
That would certainly wind up costing more longer term because it's by far the best Winter plan.
Decisions, decisions.
Also not impossible they start asking for proof on renewal and then I can't anyway.