Looking at getting solar pv

Unseul

Unseul

Unseul

Soldato
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Isle of Wight
Looking for help/advice/recommendations etc.

Looking at getting a solar system fitted. Have decided against a battery since it's just not cost effective at current prices that I can tell, even with the potential for energy credits/trading with some companies.

Been offered a 5.1kW system for £5200, or a 7.4kW system for £6500.

Now obviously the £6500 is the better deal, but not sure if we can go that big. Panels would be in different places across the roof, about half facing south, half facing west (just off in both cases, so slight south westerly).

We currently use around 6kWh a year, I work from home, and we have a small electric car, that we can try and focus on charging during daylight hours to maximise use.

I tried a solar calculator, and it reckoned we'd be able to export the power for about £330, obvious using it is even more cost effective. Presumably electricity prices will continue to rise.

The company selling it to us reckons we can save about £460 a year in electricity costs (currently we'd look at paying around £720, so I'm not so sure), and sell the rest for about £200. I can't see those figures being right myself, but could easily believe £500 in total. Meaning even without inflation/rising costs, it's paid off in 13 years, doesn't look too shabby?

The smaller system would obviously have a longer payoff.

Thoughts?
 
Unseul said:
Looking for help/advice/recommendations etc.

Looking at getting a solar system fitted. Have decided against a battery since it's just not cost effective at current prices that I can tell, even with the potential for energy credits/trading with some companies.

Been offered a 5.1kW system for £5200, or a 7.4kW system for £6500.

Now obviously the £6500 is the better deal, but not sure if we can go that big. Panels would be in different places across the roof, about half facing south, half facing west (just off in both cases, so slight south westerly).

We currently use around 6kWh a year, I work from home, and we have a small electric car, that we can try and focus on charging during daylight hours to maximise use.

I tried a solar calculator, and it reckoned we'd be able to export the power for about £330, obvious using it is even more cost effective. Presumably electricity prices will continue to rise.

The company selling it to us reckons we can save about £460 a year in electricity costs (currently we'd look at paying around £720, so I'm not so sure), and sell the rest for about £200. I can't see those figures being right myself, but could easily believe £500 in total. Meaning even without inflation/rising costs, it's paid off in 13 years, doesn't look too shabby?

The smaller system would obviously have a longer payoff.

Thoughts?
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Their numbers are always way off.

It will take 20 years IMO to payback the original set up.

Also inverters usually last 10 years so you will need 2 of them within that time at £1k each plus installation. So add another 3 - 4 years to pay for them.

So 25 years to break even. Then you can make a profit.

I'd take your £7k and either overpay the mortgage. Or stick it in an isa and add to it and move to a better home in a few years.

That's the problem with solar panels.

Are you 100% sure you will be living in that home in 40 years time? Because 25 years to pay off you want at least 15 years of profit.
 
Not everything is about profit and loss. Get solar if you are forward looking and want a better cleaner electricity supply, and maybe help the planet for the next generation.
 
We're already buying green electricity but interested in the next step. The calculator i used was an independent website not from the sales blurb. That gave £330 purely from export. That would be 20 years pay off. The fact we'll be using it as well will save even more. Throw in increasing energy prices and it works out even quicker. It's not entirely about profit either.

Inverter has 10 year warranty, so think it'll be ok
 
Unseul said:
Can you show me what your numbers are based on? Estimates etc?
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I own solar panels so they are based on that.

I however got Fit before it was discontinued which means I'm in a much better position in terms of payback period.

Also you will need to get the company to install bird proofing cage wire round the install.

Unless you like pigeons ******** all over your cars and property and them purring away all night and day.

That again is additional cost. Solar panels are natural shelter for them. As soon as I got my proofing installed I had a neighbour come and ask me where I had it done as he has the same issue. All my pigeons now moved to another neighbours house next door and I can still hear them but not anywhere near as bad as before.

So once you pay for that it will be £500 that's another years payback to add on.
 
Psycho Sonny said:
Also you will need to get the company to install bird proofing cage wire round the install.

Unless you like pigeons ******** all over your cars and property and them purring away all night and day.

That again is additional cost. Solar panels are natural shelter for them. As soon as I got my proofing installed I had a neighbour come and ask me where I had it done as he has the same issue. All my pigeons now moved to another neighbours house next door and I can still hear them but not anywhere near as bad as before.
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Strange as we don’t have any bird proofing on ours and don’t seem to have any issues with birds of any kind. We get pigeons around here but they mainly frequent a neighbours garden as he feeds them I think.
 
We have lotsof birds hence already including the netting.

Sonny how big is your system and how many kwh does it produce each year? Southerly facing and roughly where in the uk?
 
Unseul said:
We have lotsof birds hence already including the netting.

Sonny how big is your system and how many kwh does it produce each year? Southerly facing and roughly where in the uk?
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I'm in Scotland, it's southerly facing.

It's a 2kw inverter but the panels produce more I think maybe 2.2 or 2.4.

You want to over spec on the panels slightly and smaller inverter it's more efficient that way.

We could have gotten a bigger system but would have been not as efficient as then your using parts of the roof that don't get constant light.

1,808 kWh per year on average. From 2kw inverter.
 
Doobedoo said:
Strange as we don’t have any bird proofing on ours and don’t seem to have any issues with birds of any kind. We get pigeons around here but they mainly frequent a neighbours garden as he feeds them I think.
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Well I've had issues and 2 of my neighbours so it is very common.

You must have panels which are tighter to the roof or something.
 
1800kwh in Scotland from 2.4

I'm working on calculation of 6000 from 7.4. Seems fairly accurate seeing as I'm on the isle of wight. Don't think £500 is an unrealistic amount per year. Which is 13 years pay off. Not even taking into account increasing electricity prices.
 
Unseul said:
1800kwh in Scotland from 2.4

I'm working on calculation of 6000 from 7.4. Seems fairly accurate seeing as I'm on the isle of wight. Don't think £500 is an unrealistic amount per year. Which is 13 years pay off. Not even taking into account increasing electricity prices.
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It's not 2.4 though it's 2.

The way an inverter works it can only give a max of 2 however to get maximum efficiency you need to over spec on panels.

Also you get 2p for every kWh you don't use. And you save what 10-15p for every one you do use.
 
Unseul said:
I thought you were referring to your panels. What's the wattage of your panels?
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I have 9 times 280w panels.

With a 2kw inverter so 2.5kw panels feeding a 2kw inverter.

Based on your 7.4 system you will be best getting a 5kw inverter unless it's a perfect set up in a sunny location.

That way you will see 2.5 times 1800 kWh per year if you were in my location. So 4500 kWh per year

Which is 75% of your calculations like I said they are usually way off.
 
You should get a quote for your system using micro inverters if you wish to make the most of the system, it'll be a bit more expensive up front, but your system is much more efficient, as they are 'smart', and the long term running costs would be lower as if a individual panel/inverter failed you can see which one it is immediately and replace it, or just continue without it.
 
Journey said:
You should get a quote for your system using micro inverters if you wish to make the most of the system, it'll be a bit more expensive up front, but your system is much more efficient, as they are 'smart', and the long term running costs would be lower as if a individual panel/inverter failed you can see which one it is immediately and replace it, or just continue without it.
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Yeah I saw on YouTube jerryrigeverything done that. His setup was really nice. No doubt cheap too because of who he is.

Much much better system than what we usually get over here.
 
Isle of wight recieves about 33% more hours of sun than Scotland (potentially upto 60% more). 33% increase of 4500kWh is 6000kwh. Which is what the calculators were showing.
 
Unseul said:
Isle of wight recieves about 33% more hours of sun than Scotland (potentially upto 60% more). 33% increase of 4500kWh is 6000kwh. Which is what the calculators were showing.
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Yes, and as per above if you use a micro inverter based system you'll get even more, as the individual panels work at maximum efficiency rather than using hte weakest link as they do in a series connection to a main inverter.

A good solar company will come out and measure the sun with a Solmetric solar analyser or similar device, and they will show you exactly what % to expect and can give you an indication of panels that will get the least light etc. Using the micro inverter system also means it is easy to expand the system at a later date.
 
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