Solar TCO over time

kippy · 08-09-2022 7:37pm #1

Hi all,

There may be something on this forum addressing this but I'd like to see what the total cost of ownership/ongoing running(maintenance costs) are involved in a solar PV system.

There's a lot of talk about the initial install cost and grant funding for this etc but I don't see a huge amount about the warranties, general reliability and costs to fix various things with the system over time. I appreciate PV has only gotten REALLY popular the past 5 years or so so long term there mightn't be much data on this.

So, are there any opinions on this topic - what are the pitfalls over time, what costs might be associated with maintenance and what components of the system are most likely to fail first?

I suppose this type of thing may not be thought about too much in the generaly conversation about "payback" relative to other technologies but I think it's an important factor.

Thanks in advance.

Ubbquittious · 08-09-2022 9:04pm

It is set and forget for most unless you desire to keep meddling with the system. Apart from the odd inverter blowing up almost nothing

kippy · 08-09-2022 11:16pm

https://www.boards.ie/discussion/comment/119592765#Comment_119592765

Over what time period have you had the system in place?

slave1 · 09-09-2022 4:42am

I know one early adopter, 8 years in, nothing broken, had a bank of 200w panels which he recently replaced with higher rated ones, sold them to an off grider (yes, they exist)

yankinlk · 09-09-2022 6:04am

Another great thread. There is a misconception that there is annual maintenance with PV. I heard a friend at work, very smart guy, but getting PV mixed up with solar tubes. No consumables in my PV system...

It also means there isn't a repair/service industry so be sure to buy from a trusted company that's going to be around a few years.

jkforde · 09-09-2022 7:22am

https://www.boards.ie/discussion/comment/119593695#Comment_119593695

last bit is important esp. non-tech, DIY types, hope our Fermanagh friends don't pack it in too soon.

Ubbquittious · 09-09-2022 11:01am

https://www.boards.ie/discussion/comment/119593452#Comment_119593452

I'm a meddler, started off with a measily 250w about 4 yers ago, then went to 600, now 2.4kw and will probably expand again

ELM327 · 09-09-2022 11:09am

The whole benefit of solar is that there's very little to go wrong. You can also iterate over time.

kippy · 09-09-2022 11:26am

https://www.boards.ie/discussion/comment/119594845#Comment_119594845

If you iterate over time, do you ever actually make back what you put in? (Granted with regular energy prices increasing these TCO's calculations can change a lot.)

Just to clarify what I am getting at here. In the main, traditional electricity generation works on a model of "someone else is responsible for the generation of the electricity, the upkeep of the equipment, transmissions and storage of product - in fact the electric can come from any number of sources in reality"

That take a lot of hassle off you, the homeowner. If you need to iterate equipment every few (are we talking 10 years or more here) where does the "payback" come from?

slave1 · 09-09-2022 11:55am

https://www.boards.ie/discussion/comment/119594940#Comment_119594940

The focus here should be to manage your install costs, if you negotiate at the best level and take on some work yourself then the payback will be considerably more efficient and thoughts of replacing inverters etc become (relatively speaking) noise.

My first (installer) install was tracking 9year payback, second DIY install with battery has pushed cumulative total to around the 12/13 year mark payback.

I've got very low rates for electricity, if I was to use some of the rates mentioned here then my payback would be years sooner.......but I'm not that naïve

bullit_dodger · 09-09-2022 12:00pm

https://www.boards.ie/discussion/comment/119594940#Comment_119594940

Once you pay your initial outlay to get the panels in, guys on the roof etc, spark to wire the thing up - there's nothing else, your done. You can sit back and do nothing for the next 20-30 years. Possibly more.

Like all electronics, things break. Tv's go on the blink, as do washing machines, dish washers, computer hard drives, headphones, etc. Inverters and batteries are no different. You might have one for it's entire lifecycle and not a peep out of it, or you might have to replace it after 1 week (in warranty so free to you).

Not sure I understand what your saying "where does the payback come from". The payback is that you generate electricity for "free" once you have the panels, as in you don't pay for that unit of electricity......as opposed to paying €0.30 (or more) from the grid. You do 5000 of those a year and that's €1500 that you didn't have to get from the grid. Over 10 years.....well you get the idea I'm sure.

kippy · 09-09-2022 12:07pm

https://www.boards.ie/discussion/comment/119595098#Comment_119595098

And this is the crux of it. Is there anyone on this forum who has had a system for ten years, could outline their total install cost and maintenance issues and say they have produced and used the amount of electricity you are suggesting is possible to generate?

bullit_dodger · 09-09-2022 12:18pm

Be surprised if anyone here has a system for 10 years. Some people have various systems for 5-6 and upgraded/added to them over the years.

I think however, your over-worrying on the maintenance side of things. There's nothing to maintain. Nada. Zip. it's not like a boiler which you need to get serviced once a year. You need to think more like a fusebox or a television. How much work have you done on "maintaining" your fusebox or television over the last 10 years? It's that sort of thing.

Well installed Solar installation is the same. Zero maintenance.

slave1 · 09-09-2022 12:30pm

https://www.boards.ie/discussion/comment/119595131#Comment_119595131

Short answer is no, you can extrapolate annual generations from the Yearly Output thread (go look for it, search function poor), panels have very low and steady degradation curve, even after 20years they will still be at ~80%

DC999 · 09-09-2022 12:42pm

Hey @kippy. What do you want to find out?

Are you looking at solar but unsure are their hidden costs you want to include so you know the overall cost? Good question so you know your overall payback. And that has been answered here now.

I got solar a month ago and bar the inverter, the rest is dumb electrical stuff that shouldn't fail. Its just wiring. Panels have a 25 year warranty. I know I may have to replace the inverter at a point in time when 5 year warranty expires if it fails. Will cost hundreds only to replace plus sparks an hour or two to swap out.

Or are you unsure what solar in Ireland in the real world? If you want to see real world Irish stats look at the 'montly stats' thread (not exact name). In that people list what they produced and used. And there is also a monthly and yearly excel view of that in one of the stickies.

Or is it something else?

People can add to it when installed. But don't have to. You might decide to add more as we're all moving to more electric houses, cars, heating....

And based on what I've seen on YouTube and other places, you get your fastest payback from the initial install. But...all bets are off there now as we head for huge energy price rises.

fluffykre · 09-09-2022 1:24pm

I have my panels for around 2 years recent image above. Only maintenance concerns I have is getting the panels washed to stop the build up of bird poo. I haven't done it yet was quotes around 150 reach an wash with deionized water.

If rain does not clean the ingrained poo could it corrode the panels over time or create accumulate shading which reduces effectiveness this would be my concern. I may get them washed one day and see how effective it is 😀

Anyone else maintenance include cleaning their panels?

kippy · 09-09-2022 2:27pm

https://www.boards.ie/discussion/comment/119595309#Comment_119595309

I want to get a a fairly solid idea of what this "free" electricty actually costs and whether the amount of electricity that could be generated in my location justifies whatever the initial outlay will be.

Its fine saying that that we might add more panels down the line etc as we move towards more electric houses but each of those (houses, cars, heating) incurs a significant up front expense on top of your solar system investment.

Anway, I digress. A 10,000 euro investment in solar (and I amn't sure ye if and exactly what I would need, but lets just say 10K equates to approximately 8 years (even at current and near term and predicated prices) of electricity bills for me.

I know, almost for a fact, that even if I put a 10K system in, I will need to have a backup of grid electricity and during the a large percentage of the year (and the day at certain times of the day) I will need to buy units from the grid to suppliment the solar power. (Let me know if I am incorrect on this) The extent of this is currently unknown (I will do some more research in the tread ye've referenced here)

So the 10K wont cover ALL of my electric needs for the next 8 years. It will cost MORE than that - I don't know how much more but would it be fair to say it will cost more?

If it does cost more that 8 year result I came to above, get's pushed out by X years to the point where I would like to know at X years what kind of state would the panels and general tech be in?

The long and the short of it is, I am trying to see whether that 10K is best invested in solar, of left sitting the in bank account to pay my electric bills for the next 8 Years.

As you begin to add batteries to the system it gest more expensive changing the numbers and as you use solar for more (as mentioned above) you have to put more money into the system to get to that point.

I amn't convinced that the FIT system is fit for purpose either and is a long way from being fit for purpose.

Again, I am looking at this as what is best to do with the 10K. Get something shiny and relatively new or continue to pay someone else to worry about supply of electricity into my home.

And granted, energy costs are going up - is this going to continue for the next 8-10 years or is energy going to go down - I know this is something we have no control over directly but it needs to be factored in.

Thanks for all the advice and commentary so far.

jkforde · 09-09-2022 2:36pm

West of Ireland, mother nature is my maintenance crew 🌧️💨🌧️💨

bullit_dodger · 09-09-2022 4:00pm

https://www.boards.ie/discussion/comment/119595871#Comment_119595871

You should have a look at the FAQ. A lot of what you are asking, are questions which have already been answered in that FAQ.

Interested in Solar PV? Read this FAQ first. — boards.ie - Now Ye're Talkin'

it's why it was written :-)

But to answer some of your more general questions, a solar installation will more than cover your usage in the bright sunny months. Typically,

Apr->Aug you will have an abundance of power and you will be exporting to the grid
March, Sept and October, you will have good days and bad days where you will have all the power supplied, and others where you might get 50%
Nov -> Feb, with the short dark days, Solar won't be able to supply your house with electricity. You will get "something" from the panels, but it will be something like 10-20% of your consumption.

Those percentage figures are very dependant on your consumption and size of the system you install. But yeah, have a read of the FAQ first, then whatever questions you still have people can sort out for you

One thing though - while fiscal payback is important......it's not the only thing to bear in mind. There is the fact that you are doing the right thing for the environment and if you have a EV for 5-6 months a year you can "fuel" it with all the power that it needs.

kippy · 09-09-2022 4:19pm

https://www.boards.ie/discussion/comment/119596300#Comment_119596300

Fair enough - will read the FAQ again - I had read it some years ago but those numbers are as I would have expected/thought.

In my case from a fiscal standpoint - it make no sense to put a solar PV system costing 10K in place. I would be better put that 10K over the next 8 years into my bills as there are far too many unknowns.

FIT being mentioned as a viable option, when you look at the numbers, doesn't really appear to be a feasible option, should massive amounts of people take advantage of it.

The right thing for the environment is a very interesting angle - if that is one of the factors that is important to you, there are ten other things you could do that would probably be better for the environment than going solar/battery, none of which would be too appealing in the modern world.

Again, thanks for the input.

randombar · 09-09-2022 4:33pm

https://www.boards.ie/discussion/comment/119596384#Comment_119596384

If you have high energy bills then putting your money into the low hanging fruit first is best, LEDs, insulation etc.

There is definitely a return though if you get a decent price. Put mine in three years ago 3.3kw for about 4k. Definitely had the return already and expanding now.

Even if you forget about PV and just charge batteries on the night saver (LifePo + Seplos + Sofar) you'd see a return in 4 to 5 years and that's before the last big increase.

DC999 · 09-09-2022 4:34pm

If you don't have 10k to sink into it (which is very understandable), have a look at solar as a service. Pay something like 40 per month for 10 years and you own it at the end. For smaller systems, it's cheaper than paying a company up-front to install. More info in FAQ above on that. Anyways, all the best with your research on what's the right fit for you personally.

bullit_dodger · 09-09-2022 4:48pm

https://www.boards.ie/discussion/comment/119596384#Comment_119596384

I'd say every single person who's installed solar in the last 2-3 years will eventually breakeven on their solar installation.

Of course, some people will break even far quicker than others (6-7 years) because they got a better deal when doing their install and were not gouged by some unscrupulous suppliers. Others wil have bought a system not fit for purpose (e.g. bought a 10Kwp system when they really should have bought 5Kwp) - but ultimately in ~10 years most will have their initial outlay back and be "earning".

FIT has only helped reduce that breakeven timeline by 2-3 years I reckon.

I mentioned that fiscal reasons are not the only reason to get solar and that environmental reasons is another. It's been well proven by multiple sources that solar and a battery is environmentally beneficial, but my point that it's not all about breakevens. There is also the ability to provide some (limited) power in a power cut, some stability and isolation if the electricity rates go mental and you are in some respects isolated from crazy bills. You also help balance the grid. Batteries are not for everyone, and indeed with FIT the need for one has been reduced.

Course everyone's value systems are different, all I'm saying if if you only look at breakevens, you might be missing a bigger picture.

FYI: The FAQ was only put together about 6 months ago, so if you read it some years ago,.....not sure what you read :-)

graememk · 09-09-2022 5:44pm

Comparing keeping your money in the bank, vs spending on solar.

After 10 yrs you'll still have the solar panels.

Last year 2021, my system saved me 800 euro off my electric bills,

Thankfully I've been on a fixed electric rate of 20c day 5c night until August, now I'm on 28day, 7.9 night . Still fixed for a year.

With my day rate going up by nearly 50%. That's gonna make a big difference on the second half of this year.

Comparing this year to last though is going to be difficult, as I've doubled my battery capacity,

con747 · 09-09-2022 8:02pm

When I was thinking about buying my system I had 2 options, leave the money in the bank and see it shrink with inflation by 10% now or invest it in something that will add value to my house, make bills cheaper, and be paid for in full with I hope 15-20 years of life left in it. It was a no brainer for me. That 10k of yours is worth 9k now with inflation and will be shrinking as the price of electricity increases every year.

More Music · 12-09-2022 3:29pm

https://www.boards.ie/discussion/comment/119596446#Comment_119596446

You have saved €4000 in energy costs in three years before any of the massive price hikes? If you have saved that much due to solar alone how much were your actual bills before the savings?

randombar · 12-09-2022 4:04pm

https://www.boards.ie/discussion/comment/119608452#Comment_119608452

Have an EV, bills were lively. Zappi + Working from home on a sunnny day is great :D

ELM327 · 19-09-2022 2:35pm

https://www.boards.ie/discussion/comment/119594940#Comment_119594940

Iterate meaining to add more panels to generate more power, cover gaps in generation, add more storage etc. You don't have to do any of these.

Most of us on this forum after getting the first install like to get more and more, and DIY it etc.

Solar TCO over time

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