Talk to me about solar panels.

tek-monkey

wanna see my snake?
My thinking is unless you're at home all day solar on it's own is wasted, there is no feed in tariff really anymore so you need a battery backup too. Thats starts getting expensive, about 7k min for a 4kw solar setup and a 4.8kwh battery. I use at least 20 units per day, so I'd want at least a 10kwh battery for solar to ever see me through the night. I expect to pay about 11k for that, and it'll generate about 3500kwh/year on average. At current prices thats £700/year, so at least 15 years to repay itself if everything runs optimally and assuming energy prices don't rise. 2 months ago this would have been saving about £525, so much longer to pay off, but energy prices did indeed go up.

What I'm interested in is maybe just getting the battery and a smart tariff, and charging the battery at night giving myself a guaranteed 10kwh/day @5p/kwh. In todays tariffs it'd essentially cut my bill in half, as 10 would be at 75% off and 10 at normal price. My electricity spend is around a grand per year but I guess more now, so halving that without even needing the solar would be great. Balancing the two so I get a full battery on the cheap at night then topped up with solar in the day would obviously be even better, but I need to work out repayment times. If it'll pay for itself within the warranty period at todays prices I'll bite, because in 10 years time it'll be worth lots more to me in savings.
 

Cue

Well-Known Forumite
What I'm interested in is maybe just getting the battery and a smart tariff, and charging the battery at night giving myself a guaranteed 10kwh/day @5p/kwh. In todays tariffs it'd essentially cut my bill in half, as 10 would be at 75% off and 10 at normal price. My electricity spend is around a grand per year but I guess more now, so halving that without even needing the solar would be great. Balancing the two so I get a full battery on the cheap at night then topped up with solar in the day would obviously be even better, but I need to work out repayment times. If it'll pay for itself within the warranty period at todays prices I'll bite, because in 10 years time it'll be worth lots more to me in savings.

The nerd in me kind of wants the battery just to have a battery backup in the event of a power cut to be honest… that’d be pretty cool

Not that it’s a common occurrence mind you
 

tek-monkey

wanna see my snake?
The nerd in me kind of wants the battery just to have a battery backup in the event of a power cut to be honest… that’d be pretty cool

Not that it’s a common occurrence mind you

Yeah, a whole house UPS is pretty cool!
 

tek-monkey

wanna see my snake?
Anyone considered a wind option? Anyone know where I can get good data on Stafford past wind conditions to see if it's worth bothering?
 

The Hawk

Well-Known Forumite
Anyone considered a wind option? Anyone know where I can get good data on Stafford past wind conditions to see if it's worth bothering?
Between 2006 and 2009 B&Q did a "1kW" domestic wind turbine for under £2,000. They were withdrawn after being found to provide substantially less power than claimed.

I would think the technology has improved significantly since then. Even so, if I go down the route of home generation, I think it would be solar for me, as at least then "any way the wind blows doesn't really matter to me, to me".
 

Gramaisc

Forum O. G.
'Meteorological' wind data for the general area may not apply to your specific location. There can be large variations in air movement near ground level, due to local topography, trees, buildings, etc - these variations will generally lower the energy available.

But, the wind is out at night, when the Sun isn't.

Near to our place in Ireland are large onshore wind farms, which sometimes seem to be running at a good output on days which seem to be a flat calm at ground level.
 

tek-monkey

wanna see my snake?
Between 2006 and 2009 B&Q did a "1kW" domestic wind turbine for under £2,000. They were withdrawn after being found to provide substantially less power than claimed.

I would think the technology has improved significantly since then. Even so, if I go down the route of home generation, I think it would be solar for me, as at least then "any way the wind blows doesn't really matter to me, to me".

Amazon sell a 9kw one for £1500, yet the inverter appears to only support 1kw! So yeah, I think there's a lot of BS going on in how the numbers are reported, makes me sceptical.

Just had another look at that local 4kw system, peaked around 520 kwh in April and less than 100 in Feb (I think it was). With battery storage that would mean no costs pretty much in peak generation months, but I'll have a better idea once the smart meter arrives on what my usage curve is.
 

Cue

Well-Known Forumite
Amazon sell a 9kw one for £1500, yet the inverter appears to only support 1kw! So yeah, I think there's a lot of BS going on in how the numbers are reported, makes me sceptical.

Just had another look at that local 4kw system, peaked around 520 kwh in April and less than 100 in Feb (I think it was). With battery storage that would mean no costs pretty much in peak generation months, but I'll have a better idea once the smart meter arrives on what my usage curve is.

Where on earth did you get the space for a 4kw turbine? They’re not small…

It’s a very appealing prospect if you have a lot of land to be fair, if I ever find myself with acreage I’ll probably pop one up - you don’t do feed-in-tariff with big turbines… you just go to the local leccy board and tell them you want to talk business
 

proactive

Enjoying a drop of red.
I would imagine a planning application for a wind turbine in a residential area would find limited traction.
 

tek-monkey

wanna see my snake?
Where on earth did you get the space for a 4kw turbine? They’re not small…

It’s a very appealing prospect if you have a lot of land to be fair, if I ever find myself with acreage I’ll probably pop one up - you don’t do feed-in-tariff with big turbines… you just go to the local leccy board and tell them you want to talk business
Sorry, the 4kw is for solar! There appears to be 600w systems for a house, possibly 1kw, but certainly not the 9kw stated on amazon!

 

Cue

Well-Known Forumite
I would imagine a planning application for a wind turbine in a residential area would find limited traction.

To be fair I’m probably not too worried about neighbours if I have enough land to build turbines large enough to sell back to the grid

Pipe dream mind you
 

tek-monkey

wanna see my snake?
I wonder if any local companies would install kit I bought? Some much better panels around than most seem to fit, can get MSC certified 455w panels whereas most are fitting 370w.
 

tek-monkey

wanna see my snake?
Just did some very rough numbers, assuming a maximum usage of 10kw/day from solar (I use 20) and using a sample local system for numbers I'd save about £500/year with summer bills almost half the winter ones. If I could store all I generated I'd still only save about £700, so batteries purely for self storage aren't that much use.

Grid connected batteries plus solar, and using octopus go for 5p midnight electricity could save me over 1k a year, if managed/balanced right. That could pay for itself in under 10 years at my current tariff, which is my yardstick. Batteries will cost about the same as solar to install, but solar gives me self reliance to a point as increases in costs down the line are irrelevant to the portion solar generates. The main issue with batteries is savings rely on an outside agency still offering a similar tariff.

So, more sums required! Current plan is solar with a small battery setup and add them later as able (about 1k per 2kw usable storage).
 

tek-monkey

wanna see my snake?
Been thinking some more...

If you say 6k for 5kw solar, aiming for a 10 year payback to make figures easier thats £50/month outlay. My fix ends in October so I'm only paying about 22p a unit, that will go up, but if we assume 25p which is below current prices I'd need to use 200kw of self generated electricity per month to break even on solar alone. That is very roughly 6kw/day, due to a pond amongst other things my phantom load is near 500w so 12 hours of not using anything else would use that. My energy profile has all main spikes bar cooking the evening meal happening in daylight (we eat late) for most of the year, so it seems likely that it will easily pay for itself. This is just solar at present, no battery as costs for those seem to be rapidly climbing.

The question is would my money be better elsewhere? My mortgage will be down to about 30% LTV very soon and my remortgage is at under 2% so putting it there instead saves about £120 a year - probably not as worthwhile. I have no other debts*, we've replaced most household items that were needed too. The cars are 8 and 12 years old but plenty of life left in them still. Losing two lodgers then my wife losing her job means we took a cut of almost 1k/m, it'll be 1.5k once SMP runs out so we're trying to get in a position where we minimise bills going forwards. We're not poor, we can live on my wages alone, it just cuts out most extravagances I've become used to!

* Apart from my student loan which I think gets wiped next year
 

The Hawk

Well-Known Forumite
Been thinking some more...

If you say 6k for 5kw solar, aiming for a 10 year payback to make figures easier thats £50/month outlay. My fix ends in October so I'm only paying about 22p a unit, that will go up, but if we assume 25p which is below current prices I'd need to use 200kw of self generated electricity per month to break even on solar alone. That is very roughly 6kw/day, due to a pond amongst other things my phantom load is near 500w so 12 hours of not using anything else would use that. My energy profile has all main spikes bar cooking the evening meal happening in daylight (we eat late) for most of the year, so it seems likely that it will easily pay for itself. This is just solar at present, no battery as costs for those seem to be rapidly climbing.

The question is would my money be better elsewhere? My mortgage will be down to about 30% LTV very soon and my remortgage is at under 2% so putting it there instead saves about £120 a year - probably not as worthwhile. I have no other debts*, we've replaced most household items that were needed too. The cars are 8 and 12 years old but plenty of life left in them still. Losing two lodgers then my wife losing her job means we took a cut of almost 1k/m, it'll be 1.5k once SMP runs out so we're trying to get in a position where we minimise bills going forwards. We're not poor, we can live on my wages alone, it just cuts out most extravagances I've become used to!

* Apart from my student loan which I think gets wiped next year
I've been thinking a lot as well.

I've been getting quotes for solar and batteries recently and this is where I am at:

1) I've just purcahsed a share in Ripple's next wind farm, which seems to have a much better rate of return that solar panles on my roof.

2) Before my wind farm starts generating next year, I wanted to install batteries to run off Octopus Go. At that point my wind farm credit should exceed my outgoing payments for Octopus Go, meaning my electricity expenditure should actually be income (i.e. minus expenditure).

3) The along comes Rishi Sunak with his solar+ batteries = zero VAT, but batteries on their own = 20% VAT. I've been rerunning the figures, but I can't justify the cost of the solar panels (even with zero VAT), when compared to the wind farm.

I think I might sit back a little bit longer, in the hope that the VAT comes off the batteries or I might go with an initial 8.2kWh battery and expand the system later.

Further down the line, I want to switch from gas to electric heating (heat pump) so, at that point, I'll need to buy extra wind farm capacity and expand the battery system.
 

tek-monkey

wanna see my snake?
So if I pay them 4k now, in 18 months they start generating and from then on my electricity is free? Have I missed something obvious here as that seems too good an offer, and it says I'll save 300 a year which is nowhere near what I pay. I use about 7000kw
 
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