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Thanks mate, I am not convinced though, do you have figures that explain the economics being good comared to the install and materials price? every quote I have had does not add up based upon 6 panels with a 10 year lifecycle
nothing about my panels suggest a ten year life cycle tbh, the efficiency drop offs now point to something more like a 20 year useful life IIRC. I intend to post my full year figures in here next summer. I think only with a full year of data can you really arrive at any conclusions.

I also have the somewhat luxury that I bought mine outright, in an exercise in trying to minimise my exposure to the oil and gas industry (shares from a previous employee)
 
Also, if you are looking at 6 panels, that must only equate to around 2.5kw at peak generation in the perfect conditions? Personally for what its worth, I think to make solar work you do need a good number of panels + battery as otherwise you'll always be pulling from the grid when you have anything high powered on.

I've a 6kw system and have generated about 6300kwh over the past year. ~2500kwh dumped into the grid, rest used myself. peak generation is around 4700watts at max sun. I do have 9.6kwh of battery as well which really helps store the surplus i generate that i can draw on in the evenings. I haven't worked it out to the nth degree, but I reckon I will have a return on investment in about 8 years due buying very little electric now.. i was lucky in that i got in last summer before it all went a little crazy with prices going up and stock running out.

Not sure if it will, but i'm optimistic that its added a little bit extra value to the house as I do intend to move in about 6 or 7 years time so definitely a big selling point imho as i won't be taking them with me.
 
Not sure if it will, but i'm optimistic that its added a little bit extra value to the house as I do intend to move in about 6 or 7 years time so definitely a big selling point imho as i won't be taking them with me.

That is a very good point, they may not add a huge amount to the value but they will make your house a lot more attractive to a buyer when compared to one that doesn't have them.
 
For the majority of people and roof space it does not work economically. In my house the equation is 22% and the rest would be grid. Plus sell to the grid the invome is again is poor now. Economicaly that is nonsense so forget it.
 
For the majority of people and roof space it does not work economically. In my house the equation is 22% and the rest would be grid. Plus sell to the grid the invome is again is poor now. Economicaly that is nonsense so forget it.
I'm on a fixed export rate of 15p/kWh to the grid which is more than I thought. Agile tariffs vary, and in a lot of case, you can get more for export than you pay. This results in you charging up then dumping back to grid repeatedly.

Whether or not I can be arsed monitoring it to that degree is yet to be seen. I will probably try agile, maybe come summer.
 
I'm on a fixed export rate of 15p/kWh to the grid which is more than I thought. Agile tariffs vary, and in a lot of case, you can get more for export than you pay. This results in you charging up then dumping back to grid repeatedly.

Whether or not I can be arsed monitoring it to that degree is yet to be seen. I will probably try agile, maybe come summer.
What year did you secure that? Think I’m 4p for export and around the same for generation.
 
I am thinking of getting a company in to see what I can produce. Don't really care about making money, if thr cost covers the cost I pay out for electric then that is fine.
 
Below is a table of my monthly electrical consumption (first figure) and the expected output from a 4.1kW solar array. Facing south with no shading for Northern Scotland.

Jan 422 93
Feb 359 164
Mar 340 315
Apr 331 423
May 321 520
Jun 295 454
Jul 348 456
Aug 311 398
Sep 340 307
Oct 393 203
Nov 432 120
Dec 460 72

It is only during Apr to Aug that it actually produces more than I use.

My roof isn’t suitable for the array, but I have enough land to ground mount the array.

I’ve been verbally quoted around £8,000 for the array.

At best, if I could use the entire year’s generation at £0.38 including VAT, it would save me 3580kWh x £0.38 = £1360.40 / year.

This will take £8000/£1360.4 = 5.88 years.

However to use all of the electricity generated it will rely on battery storage.

I was quoted £4300 for effectively 4kWh of usable energy from a battery, which actually won’t cover my overnight usage. Or £7000 for 8kWh.

So now my payback becomes £15000 / £1360.40 = 11.02 years.

The warranty on the inverter and batteries is only 10 years, so it’s not economic to install.

I haven’t allowed for inflation in the price of electricity, but as more renewables come on stream, and there is downward pressure on the use of fossil fuels, then I believe that electricity will be less than £0.38 per kWh by spring 2024.

It is only as high as it is, because it’s pegged to generation from gas turbines. These are typically 5 to 10 times more expensive than renewables.

I aren’t anti Solar, I’m just a realist.
 
Below is a table of my monthly electrical consumption (first figure) and the expected output from a 4.1kW solar array. Facing south with no shading for Northern Scotland.

Jan 422 93
Feb 359 164
Mar 340 315
Apr 331 423
May 321 520
Jun 295 454
Jul 348 456
Aug 311 398
Sep 340 307
Oct 393 203
Nov 432 120
Dec 460 72

It is only during Apr to Aug that it actually produces more than I use.

My roof isn’t suitable for the array, but I have enough land to ground mount the array.

I’ve been verbally quoted around £8,000 for the array.

At best, if I could use the entire year’s generation at £0.38 including VAT, it would save me 3580kWh x £0.38 = £1360.40 / year.

This will take £8000/£1360.4 = 5.88 years.

However to use all of the electricity generated it will rely on battery storage.

I was quoted £4300 for effectively 4kWh of usable energy from a battery, which actually won’t cover my overnight usage. Or £7000 for 8kWh.

So now my payback becomes £15000 / £1360.40 = 11.02 years.

The warranty on the inverter and batteries is only 10 years, so it’s not economic to install.

I haven’t allowed for inflation in the price of electricity, but as more renewables come on stream, and there is downward pressure on the use of fossil fuels, then I believe that electricity will be less than £0.38 per kWh by spring 2024.

It is only as high as it is, because it’s pegged to generation from gas turbines. These are typically 5 to 10 times more expensive than renewables.

I aren’t anti Solar, I’m just a realist.
This is what I found when looking at a Tesla power wall during my install 6 years ago.

Panels will be paid back in 2 years or less now due to the increase but the power wall was years longer. Way past its warranty
 
I had mine installed 14 years ago with a guarantee, not warranty, for inverter and panels for 25 years. Have I made my money back? Yes I have, at who's expense? The expense of those without solar who are paying for the FiT I receive.
 
Fair play, must be the first self described realist iv seen who thinks consumer prices are actually going to drop any time....
 
Yeah i'm not so optimistic on prices going back down.. I think the ~40p/kwh is here to stay.. Whilst we will bring on new power sources over the next few years, our own demand for electricity is soaring and will continue to as we all transition to EV's (and induction and electric based heat sources etc) over the next 15years.
 
Jan Rosenow
@janrosenow

Solar is on a roll.
The world installed 10x more solar in 2021 than in 2010.




1668371536410.png
 
It would be class if the climate was irreversibly ****** because we accidentally hoovered all the energy out of the sun
 
Installing an air source system and running it off your power is possible and can make you almost entirely energy self-sufficient.

Rubbish, you would NEVER generate enough energy with a typical domestic array to run any amount of heating during winter in the UK.
 
I have 15Kwh (12Kwh available) of battery storage. Over winter the solar availability is minimal compared to the summer and from November to March I charge the batteries to 100% overnight at cheap rate. On a typical overcast winters day I'll be back on the grid in the evening.
I'm using gas for heating. If I went air (or ground) source heating I'd be blowing my battery storage in hours.

The technology is good but it's not a miracle solution. I can remember a solar salesman telling me my panels would charge by starlight... aheadbutt
 
The technology is good but it's not a miracle solution. I can remember a solar salesman telling me my panels would charge by starlight... aheadbutt
I remember at the time I got mine the tagline was “solar panels will generate electricity even on cloudy days”. It is true, but, in the case of my system, it is more like 200w as opposed to ten times that amount when it’s sunny.
 
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