Solar Panels

[M4tt]

The previous owner had it done back when the subsidy was 43P and it brings in a tidy sum. The law recently changed so that you can exceed the max amount, in my case 4KWH, without penalty. In the summer it peaks at about 4KWH and in the winter at about 2KWH, which is definitely helpful. I'm seriously considering doubling it, so it's 4kwh in the winter and 8KWH in the summer. because that would pretty well eliminate my bill and maximise the money coming in. I'm unsure about a battery at this point as they don't last that long compared to the panels which seem pretty well indestructible.

[gunner]

I'd say a home visit and survey is a must - we've ended up completely changing the number and position of panels.

Battery is an expensive addition but we've gone for it to bridge the gap between production and use and give a bit of protection from power cuts!

[tertius]

The previous owner had it done back when the subsidy was 43P and it brings in a tidy sum. The law recently changed so that you can exceed the max amount, in my case 4KWH, without penalty. In the summer it peaks at about 4KWH and in the winter at about 2KWH, which is definitely helpful. I'm seriously considering doubling it, so it's 4kwh in the winter and 8KWH in the summer. because that would pretty well eliminate my bill and maximise the money coming in. I'm unsure about a battery at this point as they don't last that long compared to the panels which seem pretty well indestructible.

I think you mean kW not kWh?

i.e. peak output from the system is about 4 kW?

My system is 4.32 kW (12 panels) but that is the theoretical maximum output assuming 100% efficiency which you won’t ever see of course. On a good day in summer it will generate about 25 kWh, on a normal day in winter I’m lucky to see 1 kWh!

For the OP: I think the key questions I would raise are:
1. What is their ongoing support like - including advice not just sorting actual problems - can they refer you to real customers you can talk to? Or can you find some independently (better of course)
2. What is a realistic expectation for generation and how will it change over the year - see my comment above re. the difference between summer and winter. The main reason I see such a difference is the lower angle of the sun, and some trees that obscure the panels at that low sun angle
3. re. batteries consider your consumption profile and how it will fit to the generation profile - typically panels generate during the day but you use most at night - a battery allows you to store during the day and use it later. As there is no meaningful feed in tariff these days you’ll basically be giving away the excess. If you can try to shift consumption to the daytime when you are generating - dishwasher and washing machine and so on.

Like others my main objective was not financial but to feel I was contributing a bit to the environment.

Forgot to say I have a battery - 7.2 kWh vs my average daily consumption of 8 kWh - ideally I’d have a bigger battery, say 12 kWh so you have more than a day in reserve in the event of some crap generation days.

Also noted some comments about power cuts - note that your system has to be setup with the ability to isolate itself if it is to continue to provide power in the event of a power cut. Most systems will not do this and so they power off as there is otherwise a risk that they will energise the grid while it is being worked on.

[gunner]

Also noted some comments about power cuts - note that your system has to be setup with the ability to isolate itself if it is to continue to provide power in the event of a power cut. Most systems will not do this and so they power off as there is otherwise a risk that they will energise the grid while it is being worked on.

Yes, I think it's a common misconception and one I certainly hadn't realised until recently.

[garmee]

Yes, I think it's a common misconception and one I certainly hadn't realised until recently.

My system does take over and continue to power the house while there's a cut. Depending on the type of cut, it can take over seamlessly or sometimes I have about a 4 second gap before it kicks in.

[gunner]

Yes, mine will too, I just meant that it's easy to make the assumption wrongly.

[g40steve]

Re power cuts, no battery & solar should power your home during power cut without additional wiring usually called ‘Island mode’

In the event of power cut your isolator will shut down so you are not sending to the grid, in Island mode the house senses the cut & switches to battery & solar but cuts ties to the grid.

[MattH]

The previous owner had it done back when the subsidy was 43P and it brings in a tidy sum. The law recently changed so that you can exceed the max amount, in my case 4KWH, without penalty. In the summer it peaks at about 4KWH and in the winter at about 2KWH, which is definitely helpful. I'm seriously considering doubling it, so it's 4kwh in the winter and 8KWH in the summer. because that would pretty well eliminate my bill and maximise the money coming in. I'm unsure about a battery at this point as they don't last that long compared to the panels which seem pretty well indestructible.

When did the rules change ? When my system went down last year and I was concerned I would need to replace the panels - I would have had to inform the FIT company on any changes to my system and they would prorate the payments to exclude the additional generation.

Had panels for 11 years - it earns about 1000 a year as its in the old “good” fit payment scheme. No batteries so if I was not working for home most of it would just go to the grid.

It was worth doing for the payments - but its probably just about paid for itself now.
But if things go wrong there is no cheap fix. Had to replace the invertor once, that was 1k and then the system just stopped working. Seems a connector to one of the panels had split and failed (over the years) under the panels which then took out the string.
It was a quick fix - the guy just had to replace the connector! - but it still cost 1k for the scalfolding to be put up so that the panels could be worked on.

Lots to think about for new installs today - they are cheaper to buy - but the subsidy is not there in the same way now. And of course in the winter be prepared for the system to generate nothing - other than odd days.

cheers

matt