How much are Solar Panels worth

tnegun said:
Very little maintenance is required if installed properly in the first place. Ours will be installed 4 years this February, and after some initial issues with the install we have had no issues since or any maintenance required. Our payback was coming in around 42 months, and as they were working so well, I expanded the array and added 20 kWh of batteries last January, and switched to the Pinergy plan.
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Your timeframe is too small... I wudnt expect any maintenance in the first 5 years at least (hence installers give 5 year warranty :) these systems are supposed to last 30 yrs+, you think you aint gonna have to do anything during that time?
 
conor_mc said:
Sure something could fail, but you don’t plan maintenance costs for your fusebox or your fridge, right?
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No I dont, but then again we dont have threads outlining how they are making money back on their fridge and will have the initial investment paid off in x amount of years, if we did then it should be taken into account!
 
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Colin4444 said:
I wudnt expect any maintenance in the first 5 years
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Ok but you argue that payback within 5 years isn't possible right? Payback within five years is absolutely achievable in many cases, particularly with current energy prices, smart usage, and available supports. In my case, the system will have paid for itself well within that timeframe, and it is highly unlikely to require any major replacement during those initial years. Most components come with substantial manufacturer warranties — typically 10 to 25 years, depending on the equipment — which is standard across the industry. While no product is completely risk-free long term, by the time any major degradation might occur, the system will already have delivered a significant net financial benefit.

We also qualified for a Green Mortgage rate following installation, which alone reduces our repayments by at least €100 per month. When that saving is included, the overall return on investment is even stronger.

Solar PV systems themselves are relatively simple and reliable once properly installed. Batteries do introduce additional complexity and cost, so choosing a reputable brand and experienced installer is important to minimise risk and ensure long-term support. Overall, with good system design, quality components, and typical Irish conditions, there is very little evidence to suggest widespread serious faults within the first decade of operation.
 
tnegun said:
Ok but you argue that payback within 5 years isn't possible right? Payback within five years is absolutely achievable in many cases, particularly with current energy prices, smart usage, and available supports. In my case, the system will have paid for itself well within that timeframe, and it is highly unlikely to require any major replacement during those initial years. Most components come with substantial manufacturer warranties — typically 10 to 25 years, depending on the equipment — which is standard across the industry. While no product is completely risk-free long term, by the time any major degradation might occur, the system will already have delivered a significant net financial benefit.

We also qualified for a Green Mortgage rate following installation, which alone reduces our repayments by at least €100 per month. When that saving is included, the overall return on investment is even stronger.

Solar PV systems themselves are relatively simple and reliable once properly installed. Batteries do introduce additional complexity and cost, so choosing a reputable brand and experienced installer is important to minimise risk and ensure long-term support. Overall, with good system design, quality components, and typical Irish conditions, there is very little evidence to suggest widespread serious faults within the first decade of operation.
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Please share your figures to show you will have paid off well within that period, what size system, orientation etc.. talk is cheap..

You said it, no issues within the first decade, I dont dispute this, but then you will have maintenance after this - which eats into ROI. In my case my inverter has 5 year warranty, can you guarantee (backed by money) that I wont have to replace it in yr 6? No, no one can..

Thats a big range for warranty - 10 - 25 yrs. Just to be clear the only part that has a 25 yr warranty are the panels. Everything else is 5 - 10 years, which happen to be the most expensive parts by far i.e. battery and inverter.. And these are the parts that are gonna fail...

This is what adds to my gripe, people are very vague and not specific when they talk about solar.

Just so were clear, I think solar is good, and over the long haul is a good ROI, I just think most people exaggerate payback, maintenance free, stability of the equipment over the long term..
 
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I very much agree with Colin about the investment potential but am not buying some of the figures doing the rounds. I finally met someone that had solar installed 4 years ago. Cost 13K but still has bills of approx 400 Euro per year(credits in summer offset winter bills) and has never been able to withdraw anything. He says he is saving approx 1.2K per year so looking at 10+ years payback. And he says that solar technology has advanced so much in the last 4 years that it would make sense for him to replace his panels in the coming years!!
So this is one real world example that I have heard.
 
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There are many variables to consider when calculating the ROI of solar panels or any other home improvements.

Speaking from experience my roof is South facing we got 15 panels (6.4 kwp and a 10kwh battery) installed in late October last year. My BER went up to A1. Yes we changed our behaviour to take advantage of the ev rate between 2am and 5am. Before solar panel installation we paid roughly 100 euro per month now we aren't paying anything and I'm showing 200 euro credit. The key is to get a system which will be sufficient for your needs. My battery lasts a full day which means I'm sending back any solar production to the grid at 0.25 per kwh and charging the battery at night for 6 cent per kwh.
From my estimates if I'll continue for a full year the savings will be around 2200 euro per annum. Considering my system came at a cost of 8250 euro it's not a bad investment. Naturally, maintenance will happen at some stage therefore I'm adding an extra year to payback period to account for that. So even if it takes 5 years to recoup the cost I'm still happy. You can also get an extended warranty on your battery and inverter for the peace of mind.
 
Pawel Nowak said:
he key is to get a system which will be sufficient for your needs.
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Exactly, which some ppl cant - I can only get max 9 panels due to my roof.. their will be shading on some panels etc..
You seem to have a good setup - unfortunately alot of people cant get this
 
tnegun said:
The table got mangled. Here's a screenshot
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Colin4444 said:
Please share your figures to show you will have paid off well within that period, what size system, orientation etc.. talk is cheap..
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Our original system was installed at the end of 2021. It consisted of a 4 kWp east-west array and a 5 kW hybrid inverter with no battery (batteries were still relatively expensive at the time). The total cost was €5,100, of which the SEAI grant covered €1,800.

The installation price was lower than typical for a few reasons: it was before the war in Ukraine, surge in demand, my neighbour and I used the same installer, and I received a further referral discount after recommending them to a friend.

Our electricity bill in 2021 was approximately €1,700 per year for a household of six (3 adults, 3 teenagers). From 2022 onward, despite rising electricity prices, our annual bill fell to under €900 due to self-consumption and Feed-in Tariff payments.

Based on those savings, the projected payback period was just over four years.

In 2024, I expanded the system by adding a further 3 kWp of panels and 20 kWh of battery storage at a cost of €2,500. I carried out most of this work myself, which significantly reduced costs. After 12 months, the system performance aligns with the figures shown above.

Notably, we added an EV in June and have driven nearly 8,000 km since, with around 95% of charging done at home. Even with this additional load, our electricity account is currently in credit by €134.26.

There are also several financial benefits not included in the payback calculation:
  • Savings on petrol/diesel of roughly €100 per month due to EV use
  • A reduced mortgage rate after qualifying for a Green Mortgage (minimum €100 per month saving) following BER improvements
  • Reduced gas usage, as EV rate is used to heat water when the car is not charging
  • Electricity price increases since 2021, which further improve the value of generated energy
For context on the BER improvement: we previously upgraded attic insulation, added a well-insulated extension, and improved heating controls, moving from C3 to B1 (only B3 is required for a Green Mortgage rate).

Regarding reliability, modern solar PV systems are relatively simple and have long component warranties. If an inverter were to fail outside warranty, replacement would typically cost under €2,000. Battery replacement costs are in a similar range, though such failures within the first decade appear uncommon when quality equipment is used.
 
Colin4444 said:
Exactly, which some ppl cant - I can only get max 9 panels due to my roof.. their will be shading on some panels etc..
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If I had limited roof space, I'd spend more on a big battery that would allow me to use an overnight EV charging rate (preferably Pinergy's 6c/kWh) whilst avoiding daytime import (and their painful ~40c/kWh) for all but deepest winter days. There are many ways to configure your solar generation, battery storage, and tariff combination and it's really not hard to be hitting a sub-7 year payback.
 
tnegun said:
Regarding reliability, modern solar PV systems are relatively simple and have long component warranties. If an inverter were to fail outside warranty, replacement would typically cost under €2,000. Battery replacement costs are in a similar range, though such failures within the first decade appear uncommon when quality equipment is used.
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But this is my point, if the inverter failed after 6,7,8.9,10+ years, it needs to be replaced at a cost, as you say of approx 2k, this eats into the ROI.. adds another year or 2 to your payback... Plus if anything goes wrong with the system, after the typical 5 yr installer warranty, you will have to pay to get someone to fix it.

I can see in the years to come, plenty of companies offering maintenance, repair, cleaning etc etc on all the solar systems installed in the last years...

I repeat, I see solar as good in the long run, I just think ppl dont look at the big picture... Im sure their will be a lucky few who never have issue, or small issues, but their will be people who have issues..

I had an expensive washing machine that only lasted 5 years and another (cheaper model) that is still going after 22 years!! You just cant tell how machinery will last..
 
conor_mc said:
If I had limited roof space, I'd spend more on a big battery that would allow me to use an overnight EV charging rate (preferably Pinergy's 6c/kWh) whilst avoiding daytime import (and their painful ~40c/kWh) for all but deepest winter days. There are many ways to configure your solar generation, battery storage, and tariff combination and it's really not hard to be hitting a sub-7 year payback.
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I am getting 10kwh battery.. their is only the 2 of us, use approx 3k Kwh a year, so 10 is big enough for us!
 
Pawel Nowak said:
Speaking from experience my roof is South facing we got 15 panels (6.4 kwp and a 10kwh battery) installed in late October last year. My BER went up to A1. Yes we changed our behaviour to take advantage of the ev rate between 2am and 5am. Before solar panel installation we paid roughly 100 euro per month now we aren't paying anything and I'm showing 200 euro credit. The key is to get a system which will be sufficient for your needs. My battery lasts a full day which means I'm sending back any solar production to the grid at 0.25 per kwh and charging the battery at night for 6 cent per kwh.
From my estimates if I'll continue for a full year the savings will be around 2200 euro per annum. Considering my system came at a cost of 8250 euro it's not a bad investment. Naturally, maintenance will happen at some stage therefore I'm adding an extra year to payback period to account for that. So even if it takes 5 years to recoup the cost I'm still happy. You can also get an extended warranty on your battery and inverter for the peace of mind.
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BTW 15 panels and 10KwH battery for 8250 is a very good price. Im getting 9 panels (and 9 optimisers), 10KwH battery and manual changeover switch for 8k after grant.. Just hope after sale service is good.. For some individuals I have seen the installer is very bad at any followup and in some small cases have gone out of business..

I know I seem to be bashing it and taking a pessimistic view of the whole thing, Im not, Im trying to see the whole picture so I aint surprised by anything down the line..

The impression I get, you get it installed, payback in 5 years after that its all saving, which is not realistic.. Things will happen without a doubt..
 
CuriousG10 said:
Cost 13K but still has bills of approx 400 Euro per year(credits in summer offset winter bills) and has never been able to withdraw anything. He says he is saving approx 1.2K per year so looking at 10+ years payback. And he says that solar technology has advanced so much in the last 4 years that it would make sense for him to replace his panels in the coming years!!
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What size system? As a rule of thumb it should cost 1100 per Kwp installed. If you over pay of course your payback will be longer.

His panel comment is nonsense, panels are getting more powerful because the trend is bigger panels!! The tech hasn’t really improved at all in the last five years.
 
Anything can go wrong with everything Colin. When buying a new car you don't look through every single thing that can go wrong because that would be a rather pessimistic outlook preventing you from making a purchase.
I have a 10 year warranty on the battery and the inverter even if something goes wrong some of it will be covered.
My opinion remains the same taking any downside into account is important but shouldn't be the only point.
If your roof is South facing or E/W and you have space providing you do you homework solar panels should be a good investment. A word to the wise always quote with a minimum of 5 suppliers. My first three quotes for practically the same equipment were 4k above of what I paid and that was with local trusted suppliers.
I would also recommend checking higher capacity panels my neighbour could only fit 10 panels but he went for 700w panels effectively ending up with a larger system than me.
 
Pawel Nowak said:
When buying a new car you don't look through every single thing that can go wrong because that would be a rather pessimistic outlook preventing you from making a purchase.
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A similar comparison was made previously posts 115 and 116 :)
1. For most cars are not an investment, and we dont speak about ROI
2. Cars have been around and most people have one, we all know things go wrong with cars, they cost money.. we all know they are a money pit
Pawel Nowak said:
My opinion remains the same taking any downside into account is important but shouldn't be the only point.
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So basically we agree?

Not sure where you got the impression that the downsides are the only point, I added a little disclaimer to some of my recent posts that overall I think solar is good.. Sure Im even getting solar installed myself

It seems that everyone agrees that their will be some maintenance cost, but they just dont like to talk about it for some reason, or add it to their payback calculations!
 
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