Solar panel production figures

HungryHippos said:
For most people it doesn't make sense to install solar if they don't use much, so it really boils down to what it costs you, how much it saves you, and how much it pays you. I says most as not everyone will have the same parameters to work with.

What is your expected ROI out of interest? Anything under 10 years is reasonable as things go.

I ran some figures and my install was about £8.5K and I am expecting current setup to save me £1000-£1500 per year, probably closer to the top end of that. Could even exceed it depends on unit rates and a few things.
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Im expecting around 1k a year…..but i wasnt too bothered about the roi, i had the money, it was earning zero interest, so i bought solar and as electric was getting more and more expensive, i had no issue in spending the 5k on solar
 
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Indeed - we went for as many panels as possible as we're high users (well, especially during the weekend) - but any excess can go to battery storage and then hot water but then also export which whilst not huge, over the winter period from november to end of Jan has been nearly £14 which whilst won't set anyone's pants on fire I think we'll be looking at that per month in the summer months potentially which will clock up.

So the ROI can also accelerate depending on your usage patterns - furthermore if the prices go up the ROI speeds up too.

The main reason I got them was to lower my monthly costs - psychologically, paying less than £100 per month for energy is quite an impact - but also because it's the right thing to do.
 
I think where solar doesn't make sense is when you use like 2kwh per day.

2 * 0.34 = £0.68 per day.
£0.68 * 365 = £250 per year.

It's hard to save anything with that, you'd be 100% reliant on proceeds of selling to grid, at 15p/kwh if you used none of it, a 4kw system can make something approaching 4000 kWh, call it 3500 kWh.
3500 * 0.15 = £525.

So in that sense max payment is about £500 for a year, and max usage at low level is £250, if you use some instead of selling it that goes down a bit as well.

It's definitely better the more you use, as getting paid £0.15 per kWh isn't as good as not paying £0.34 for ones you actually need to use.
 
HungryHippos said:
I think where solar doesn't make sense is when you use like 2kwh per day.

2 * 0.34 = £0.68 per day.
£0.68 * 365 = £250 per year.

It's hard to save anything with that, you'd be 100% reliant on proceeds of selling to grid, at 15p/kwh if you used none of it, a 4kw system can make something approaching 4000 kWh, call it 3500 kWh.
3500 * 0.15 = £525.

So in that sense max payment is about £500 for a year, and max usage at low level is £250, if you use some instead of selling it that goes down a bit as well.

It's definitely better the more you use, as getting paid £0.15 per kWh isn't as good as not paying £0.34 for ones you actually need to use.
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We dont use 2kwh per day everyday……..and when it is as low as 2.6kwhs a day, its because we are using the solar produced to lower the Cost, which isnt in your calculation.

The day we used 2.6kwh from the grid, we used 3kwh from produced solar and exprted the rest. So we also save 3x33 = 99p from not using the grid…..if that was 1 every day, then thats another £365 saved. So now we are up to nearly 1k a year.

But i did also state, it wasnt just about the money……its the right thing to do and i know people dont get that, but it truelly is
 
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Welshman said:
We dont use 2kwh per day everyday……..and when it is as low as 2.6kwhs a day, its because we are using the solar produced to lower the Cost, which isnt in your calculation.

The day we used 2.6kwh from the grid, we used 3kwh from produced solar and exprted the rest. So we also save 3x33 = 99p from not using the grid…..if that was 1 every day, then thats another £365 saved. So now we are up to nearly 1k a year.

But i did also state, it wasnt just about the money……its the right thing to do and i know people dont get that, but it truelly is
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You need to adjust based on your own usage figure.

If you use avg 5 kwh per day, then you'd spend 5 * £0.34 = £1.70 per day, or £1.70 * 365 = £620.50 a year without solar.

Then the numbers start to make even more sense.

Double to average 10 kwh per day and it's even better.

It's all variables and values, though solar won't reduce electric bill to £0 necessarily especially in Winter.
 
HungryHippos said:
You need to adjust based on your own usage figure.

If you use avg 5 kwh per day, then you'd spend 5 * £0.34 = £1.70 per day, or £1.70 * 365 = £620.50 a year without solar.

Then the numbers start to make even more sense.

Double to average 10 kwh per day and it's even better.

It's all variables and values, though solar won't reduce electric bill to £0 necessarily especially in Winter.
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But i cant double usage and i never said i wanted to reduce it to zero, but any reduction is netter than no reduction.

again, its not about the money, for me its the right thing to do and in future there maybe a heat pump or an ev, who knows. But right now, its reducing my monthly outgoings and pressure ( although small ) on the grid.

once i have a years worth of figures, i will see whats the best for me, but money isnt the controlling factor here.
 
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When im sat at my desk and the sun is out, i look at my IHD and see that its got the pylon sign, that for me is what its all about. knowing im helping to send green energy down the grid…….money isnt the only driver and never will be.
 
Welshman said:
When im sat at my desk and the sun is out, i look at my IHD and see that its got the pylon sign, that for me is what its all about. knowing im helping to send green energy down the grid…….money isnt the only driver and never will be.
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For me primarily financial related but I will also take the greener aspect of things.

Being a heavier user of kWh anyway, that's even more true as load off grid on my end will be higher.

So far my usage from generation is a high 90% or so, expect it go lower in the summer as I struggle to find ways to use it all :)
 
HungryHippos said:
For me primarily financial related but I will also take the greener aspect of things.

Being a heavier user of kWh anyway, that's even more true as load off grid on my end will be higher.

So far my usage from generation is a high 90% or so, expect it go lower in the summer as I struggle to find ways to use it all :)
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At the moment im exporting 63% of what ive produced…..it will only increase as we get more sun and the days get longer. Especially as from around feb to around november, i cook outside on gas.
 
I also had a go at moving some usage around just for the saving session, planned it perfectly so that the battery was empty at the right time and then fully filled it, washing machine, dishwasher, tumble drier and both heat pumps on. Id call it a success!!

Will be interesting to see the next session results as that was for 1.5hrs and again managed to time it perfectly, also poor solar so no input from the panels either.

Saving Sessions ExperimentKWH (PRE SESSION 1300-1600)COST (PRE SESSION @0.4687)POINTS EARNEDPOINTS VALUE
23/01/2023 (£3.37 or 2700 points per unit)7.9£3.7012160£15.20
 
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I've gone a different way with my DIY solar/batt setup, Its setup to draw only 1-5 watts from the grid 2.30am to 9.30pm everything else comes from the batteries.
Battery runs the house 2.30am to 9.30pm, all solar goes to the batteries, cheap rate kicks in then for 5 hours (batteries off) so immersion/washing machine etc all at 8p a unit
as well as charge the batteries when needed in the Winter months.

Saving a fortune, actual electric cost for the year will be under £100 + the standing charge ripoff!.
 
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