Manufacturers say that installing a couple of 300-watt panels will give a saving of up to 30% on a typical household’s electricity bill. With an outlay of €400-800 and with no installation cost, the panels could pay for themselves within six years.
In Spain, where two thirds of the population live in apartments and installing panels on the roof requires the consent of a majority of the building’s residents, this DIY technology has obvious advantages.
With solar balconies, no such consent is required unless the facade is listed as of historic interest or there is a specific prohibition from the residents’ association or the local authority. Furthermore, as long as the installation does not exceed 800 watts it doesn’t require certification, which can cost from €100 to €400, depending on the area.
As with all solar power systems, balcony power only works in daylight and a battery storage system can add at least €1,000 to the installation cost.
Vernetta says the vertical surface area of cities is far greater than that of the roofs and that, in Spain, balcony panels benefit more than roof panels from the low winter sun.
Cities such as Helsinki are already experimenting with buildings with solar panel cladding.
Hard pass. I don’t trust it will work in 6 years. So, it’s not really an investment.
Average solar panels are warrantied to give 100% power for 25 years. After that, they still work but at roughly an 80% rate, with a small fall off each year.
A 6 year payoff is an excellent investment. I’d gladly hang something with zero negatives on a balcony that just made me money for the rest of my life.
They don’t drop from 100% to 80% year 26. It’s a gradual but accelerating slide, with 80% still warranted at the end of the timeframe.
That doesn’t make PV a bad investment; overselling it puts people in the sceptic camp, though, which is what we’re seeing in this thread.
Its a general estimate of viability, yes. I did point out that panels drop off a bit every year, but it looks like that wasn’t clear if you feel like it needs a correction.
Every comment in here when I posted was skeptical about solar, with no stated reason. I added some general data about actual panels. If you want to add more up to date info, please do.
To be clear, I’m only wanting to clarify because I already live off solar. As such, I find it important to provide the correct information about expected panel longevity in general … getting into the weeds about things like panel type and brand tend to make people’s eyes glaze over while already skeptics, which doesn’t sell a lot of people on the virtues.
The important takeaway is, yes, this is mature tech that continues to evolve. There’s going to be loss each year, as there will be with LFP, so both can de viewed as depreciating assets when ignoring the cost savings accrued over time; however, price trends with both technologies suggest (thus far) that picking up an extra 25% of capacity in 20 years is not only doable but will actually lower the lifetime kWh cost of the system.
The real ongoing cost by then is going to be a few inverters.
If it replaced my need for a grid, I would.
It won’t, but the above replaces about 30% of power costs for life for these residents, and pays off in 6 years.
Thats still very good.
With the hell I continue to go through having made spectacularly bad choices in building out my solar, I get the trepidation. But my starting point was the grid being unreliable. If yours isn’t, great! That’s not the case everywhere, and freezing for a week changed my mind about the utility of being on-grid when I can have far more control for less money.
“Better than what I’ve been getting” is a low bar, but adequate for investigating other options. I’ve not correctly balanced everything yet. Still, I don’t just lose power because of weather hundreds of miles away, just my own inadequacy at research.
Solar panels have been out for a long time, they definitely last more than 6 years. You can easily look this up.
The warranties are usually 25 years at this point.
Maybe do some research instead of using your feelings to make every decision, you’ll get a better result.
I don’t think it really matters how long the warranty is, when the manufacturer is EGHIGXXJKNB from Amazon.
Removed by mod
Not him but here are a few links:
https://www.anker.com/blogs/solar/how-reliable-is-solar-energy
https://en.m.wikipedia.org/wiki/Solar_panel
TL;DR: Most rigid panel manufacturers provide a 25 year warranty. Performance degradation ranges from 1% to 4% per year depending on the material used, with thin flexible panels being the worst.
Oh look, a link to a solar company. Shocked.
Erm as he is talking about what the panel providers are willing to warrantee. Where else would you expect to see it.
Give me a week and I can go get the warrantee paperwork for my panels. But I’m net heading out to them till after Xmas. But it’s 20 years at something like 85% of original performance.
If you are expecting to see test data. Well, honestly, other than manufacturers. The older technologies really were not as reliable. The same manufacturing techniques that have reduced the price of panels over the last few years. Are the reason UV damage etc will take longer to effect them. Hence, the long warrantees. 70-90s panels used to suffer from UV fogging over the diodes, so did not expect to last as long. But even they tended to last about 10 years.
As I pointed out else where. It is not the panels that are likely to fail in 6 years. (unless damaged) But the electronics adjusting to battery or AC voltages for use. They tend to come with much shorter warrantees. But if fitted well, are also much easier to replace.
You can simple google it. It’s considered common knowledge at this point.
Find me something showing 25 year old solar panels that still deliver 80% or higher output.
Most haven’t been around for 25 years yet, but here’s a study on german panels at 16-20 years showing they’re just fine.
https://www.pv-magazine.com/2023/05/16/researchers-assess-degradation-in-pv-systems-older-than-15-years/
Do you expect a fridge to work in six years? Seems you’re applying an unreasonable standard to solar in a vacuum.
Honestly, it depends on what you spend. Many high-end fridges in Europe come with 10 year manufacturer’s warrantee. And EU law requires manufacturers to provide parts for 10 years on such goods. So honestly yeah.
That said, cheaper ones tend to make it past 5 (mine is 8 years old) without maintenance. And if I had to replace it 3 times in 10 years, it would still be cheaper than getting the expensive ones. (worse for the environment)
As for solar panels. I am about to replace the one on my boat. It is well over 5 years old and still works. I’m replacing it because I can get 2 410w huge panels for way less than the 100w one cost the past boat owner.
6 years really is nothing for a solar panel. My new ones came with a 20-year warrantee. (something like 85% after 20 year). High-end ones are better.
The 2 MPPTs are likely to need replacing first. But again, 6 years may be well beyond their warrantee. But is reasonable to expect. The lifepo4 battery should just manage 10 years. Before losing significant storage. But that is with the BMS set to keep them from 10-90% charge.
So no, 6 years is a very reasonable time to expect from solar.
EDIT: In a house setup. It is the inverter that is most likely to need replacing. But again, 6 years is more than likely for a quality one.
On my boat, the vast majority of the equipment is 12v, as it’s just more efficient. But the cheap (very) Chinese inverter did not last a year. So yeah they can be cheap crap if you don’t get good ones. But we don’t really use it much. So haven’t bother replacing it yet. Will do so this summer.
We agree for the most part … people unaware of how an off-grid DC setup operates fixate on the parts least likely to fail (that was me, as well, when I first started looking into things). MPPT, fuse panels and various step converters should be the anticipated replacements. They’re inexpensive compared to wholesale PV and LFP upgrades.
Grins, actually My MPPT cost more than the panels. £70 for each panel plus £33 shipping the pair. The 2 30a MPPTs £90 each.
But when fitting to a house it’s likely to be mounting by a pro that is the bigger cost. So yeah, way easier to replace the MPPTs etc then climb on a roof.
Fortunately, with a narrow boat a can do it all myself with just the risk of wet feet ;)
I’m in that in-between use where it’s a tool van. So I have acreage for solar on the roof and 1200W. I negotiated a remarkably reasonable rate with myself for the install.