My panels are guaranteed to degrade no more than 15% over 25yrs.
A standard solar panel only setup should payback 6-8yrs. Adding a battery increase it by a few years based off my usage data. The key is to know the £/kWh that you might pay for a battery.
The National Weather Service in your country (if Great Britain, then the UK Met Office) will almost certainly publish monthly (or perhaps seasonal) and annual climate summaries. Typically, these include sunshine hours and departures from “normal”.
Over its lifetime or initial outlay?
Charging batteries could be done via solar, cheaper electric tariffs (while they last) or both, and I suppose solar wouldn’t be essential initially but could be added later if you planned at battery installation.
My PV/battery setup pays for itself in a number of ways.
The batteries mean that I can run off them all day when the sun is not out.
My batteries charge at night at 7p/unit. I sell excess solar or battery discharge at 15p/unit. I tend to discharge the batteries before bed if there is any left—even now I can discharge 5 or 6 units. In summer, almost the full batteries.
So, my electricity bill is close to zero, including a standing charge of 55p/day. And I have an EV which I charge at night at the 7p rate.
Being able to store power at 7p and sell it back at 15p makes a significant contribution to my savings. And yes, I had to fork out for all this. Payback is looking like 6 to 7 years currently.
PV panels do degrade with age. Mine are guaranteed to be something like 87% of original capacity in 25 years. More significant is that DC panel output has increased significantly in the last 10 years. Typically from 250W to now 450W for a typical panel.
a quick goggle gives this sitehttps://www.statista.com/statistics/609846/total-sunshine-hours-in-england-uk/
This shows uk sunshine down in 2024 vs 2023 especially in June.
The met office used to have sunshine hours on their website but i can’t find it at the moment.
I’m still unsure about batteries in the house (for me at least). When I look at the cost compared to payback, it tends to be a long payback. I think we are still in a transition, and see in the near future the final solution would be a smallish say 5KWh battery in the house, with the EV’s 40+KWh battery being a big part of the final energy solution. Vehicle to Grid/House which for some reason is still only in trial mode.
Does Canada have E.Vehicle to House availability, in which case this might be another solution to consider and more environmentally friendly. This assumes you have an EV, or it is something you are considering
Initial outlay. So ask for quotes with and without a battery so you get a cost for the battery.
Octopus tariffs are such that it’s not always cost effective to charge batteries with solar. Export all your solar back to the grid at 15p/kWh then charge your battery overnight at 5-12p/kWh
The advantage of this approach is that you build up credits in the summer from export which offset the cost of winter usage without the need for a battery.
On the other hand, even without PV you can benefit from a battery simply by charging it off peak on a variable tariff and using that power at peak times.
I have had my solar installation since 2011. I have no battery as they were hardly an option at that time. My system is less efficient than modern systems, probably cost more but has paid for itself twice over plus.
My generation data is
2012 3722
2013 3576 96%
2014 3664 98%
2015 3431 92%
2016 3530 95%
2017 3610 97%
2018 3781 102%
2019 3724 100%
2020 3917 105%
2021 3453 93%
2022 3766 101%
2023 3461 93%
2024 3477 93%
The percentage is generation compared to (full) base year 2012, so 2018, 2020 and 2022 were good years.
My system has been a grand sucess but if I was buying now I think batteries would be the priority then solar panels.
To have a battery setup here that would run the whole home, I believe we would need at a 15 kwh set up. That’s about 15K CAD with install, but when I was looking into solar panels and a battery, I was getting prices of $40,000 thrown at me.
A generator for a whole home generator set up which would be used for outages only, is about 10K CAD, but I’d like a setup that can be used as replacement for using the grid.
I believe that a very small generator to trickle charge a 15 kwh battery setup would only be about
1 or 2k cad.
BTW, I do believe we have EV to house availability here, but not certain.
We just purchased a Mitsubishi Outlander phev that requires charging two or three times a week at 120V which is the standard power supply here, so that shouldn’t be a problem for the batteries to supply. We will most likely have this vehicle for 10 or 12 years, so moving to a full EV vehicle is not an issue for us at this point. If we end up getting one, it may require an extra add-on battery pack to supply enough power for it, without lessening the power required for the house.
The initial battery setup at 15K seems affordable and possibly it can be wired to the grid as well so that the grid would trickle charge it and most likely the cost for that bit of power would be minimal. Then, if there is an outage, the small natural gas powered generator would automatically kick in to provide the trickle charge.
I’ve had to engineer the set up for this myself because most people seem to want battery backup as solely a backup system in case of an outage as opposed to an alternate supply of electricity, which I feel is the key element.
It will be interesting to see what I come up against when actually getting it happening in a year or two. I will have many questions for Jackery (the battery supplier) and the electrician and most likely some included interaction with Generac or the like.
Should be fun.
I think you have ht the nail on the head. The systems can be so very expensive that it can put you off. A smaller achievable outlay allows you to get on the ladder at least. I paid £5.3k 6 years ago just before I retired, and it has turned out to be a no brainer.
Do you have to own an EV to benefit from such a tariff?
Simply can’t do off-road charging currently, but have plenty of kitchen/utility white goods/electric heating which could be put on overnight without bothering anyone.
Then factor in bringing millions of tons of plastic and glass panels from china in a filthy powered ship, not good IMO
Just saying
Martin
A single 450W panel would generate 350-450kWh/yr, so 12MWh over a 30yr life.
I’d hope the transportation energy would be a lot less.
Granted, the inverter may last only 10-15yrs.
No, have a look at Octopus tariffs in the UK. They do have some that cater specifically for EV users, but you can have a variable tariff without one.
A friend uses his to charge a battery during early morning and afternoon cheap rates, and this more or less covers his peak time (4-7pm) usage completely, even without solar generation.
That’s interesting, thank you.
It’s probably all out there if you know where to look but you’d think the government would have been publishing official advice for many years to help the general public assess what might be a) feasible and b) affordable for them.
I’ve long felt that many of these things are simply impractical and probably too expensive and potentially disruptive for us in the short term - that may be the case now, but less so going forwards.
Will have to take a look on the river to see if there are any good guides to this kind of thing even if I’m not in a position to move it forward immediately.
its not rocket science to realise that winter anti-cyclones frequently mean very cloudy days and so little/no solar power generation along with very low winds which also mean no power. The puzzle is that the powers that be do not understand this and yet want even more solar panels and wind turbines .
The World bank published a study in 2020 that ranks the UK as the worst country in the Worlds for solar power generation.
Our solar panels have not produced anywhere near as much as same time period for 2023/24 because we have had so few sunny days. Even a “good” winter means low production becasue 2/3rds of the day is night and also a low/weak sun means lower power generation. Even a really sunny day does not get to 100% output form the panels, in a direct south facing roof.
Stephen
Hi.
I understand that invertors are no longer installed in roof voids.
Has anybody had theirs installed outside in a “box”, if so how much space did the “box” take up?
Also if there are no spare ways in your distribution board/consumer unit does a larger one have to be fitted? If you had a new one fitted did they then test all of the electircal circuits in your property?
if you search for images of “GivEnergy inverter outdoors” you’ll get plenty links
The Publicly Available Specification (PAS) 63100:2024 provides guidance on how to install solar panel inverters and batteries. It’s a best practice guide, not a regulation, but it’s intended to help reduce the risk of fire.
Our set up, installed May 2023 is in the garage whic has firprrof ceiling and internal door.
The issue may be how house insurance companies treat intallations that do not n meet these new standards.
Stephen