Solar panels and battery - any real world recommendations?

I haven't run the numbers and maybe you're right. At the current prices of buy back. But if the installers are so busy as people say, very soon there will be a huge surplus at sunny times and the prices will go down, potentially to zero or even below.

From this perspective, if you already have panels, it's in your best interest to discourage any more people from getting them :)
 
SkyTerran said:
I haven't run the numbers and maybe you're right. At the current prices of buy back. But if the installers are so busy as people say, very soon there will be a huge surplus at sunny times and the prices will go down, potentially to zero or even below.

From this perspective, if you already have panels, it's in your best interest to discourage any more people from getting them :)
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Ha yes, that's one way of looking at it!

The good thing is we can be flexible. E.g right now most of us fully charge our batteries overnight and then export almost all our solar generation, if the equation changes and that is no longer optimal we can quickly change. However. my view is the export payments are more of a factor for those with the larger systems generating well above their actual electricity usage and most of their ROI comes from export and that is probably not a spot I would want to be in.
 
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regardless of whether i have solar or not, i'll be happy to see energy prices fall
just too dang expensive in this country, just to line shareholders pockets :/
 
200sols said:
Ha yes, that's one way of looking at it!

The good thing is we can be flexible. E.g right now most of us fully charge our batteries overnight and then export almost all our solar generation, if the equation changes and that is no longer optimal we can quickly change. However. my view is the export payments are more of a factor for those with the larger systems generating well above their actual electricity usage and most of their ROI comes from export and that is probably not a spot I would want to be in.
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For many it is a conscious decision to vastly over panel I think, specifically as a revenue stream.

Its a gamble because the options for excess generation if export doesn't pay are fairly limited.

In other news I passed the 1/3 payback point in April.
I have had two summers and three winters in effect.
I expect that with nothing major changing then in 4.5 - 5 years time, give or take a little, I would be paid back.
 
I over panelled for two key reasons:
1) summer revenue stream (make hay while the sun is shining)
2) increased winter generation - we are all electric including heating. The solar helps keep me off peak time electric for most of the day even in the depths of winter.

Hardly any of the houses round me have solar, it’s going to be awhile. I’ve also got an EV that is at home most of the week, I’ve got plenty of places to put the energy.

The likes of Australia have near 40% market penetration at the point, we have only just breached 5%.
 
SkyTerran said:
I haven't run the numbers and maybe you're right. At the current prices of buy back. But if the installers are so busy as people say, very soon there will be a huge surplus at sunny times and the prices will go down, potentially to zero or even below.

From this perspective, if you already have panels, it's in your best interest to discourage any more people from getting them :)
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You've hit on an interesting point about export prices, and yes, they could definitely change as more solar comes online. But looking beyond just the buy-back rates, there's a much larger, positive shift happening.

Think about it – solar technology is constantly improving. Today's panels are great, but tomorrow's will be even better, and older ones will eventually be replaced by more efficient options. The key thing, as you say, is that the more power we generate and use ourselves, the less strain we put on the national grid. This directly translates to lower personal energy bills and greater energy independence for households.

And if everyone, or at least a significant number of us, adopts solar? Sure, that might mean big changes for the traditional power industry, but that disruption could be a powerful force for good. We'd be collectively slashing our CO2 footprint, which is a massive win for the environment and crucial for our future. Imagine the UK leading the way, becoming an international showcase for how a nation can successfully transition to widespread, decentralised renewable energy. That's a genuinely exciting prospect and, ultimately, better for everyone in the long run, far outweighing any short-term fluctuations in export tariffs.

This is just my perspective, I may be totally off the mark.
 
b0rn2sk8 said:
Pass on 10 years and the panels on your roof will be considered obsolete just like those fitted 10 years ago are now.
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Almost ten years on and my 250w panels are rather undersized, they are also physically smaller than modern panels as well, not by much, so modern panels would fit, but it's not something I'm looking to do.

Original Sunworld panels 1675 x 1001 and just 14.91% efficient when new, my newer panels are 1722 x 1134 and 21.5% efficient.

200sols said:
I suggest doing some sums on the annual return in percentage terms. Its very comparable to the stock market with considerably less volatility
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People often suggest you'd be better off investing the money, instead of fitting solar, but they fail to deduct the money to pay the electricity bill each year, doing this usually means the pot will empty over time.
SkyTerran said:
From this perspective, if you already have panels, it's in your best interest to discourage any more people from getting them :)
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Yes, don't fit more panels it's a terrible idea! I need to keep my £5 to £10 per day rolling in.

If export rates did drop in a few years, then hopefully I'll have retired by then and the car will be available to charge at home.
 
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b0rn2sk8 said:
The likes of Australia have near 40% market penetration at the point, we have only just breached 5%.
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Just to pull that up slightly, you're forgetting the climate.

Australia (and other countries with similar levels of penetration) tend to have a much better climate for solar, which skews those figures a little.

With improvements, at the minute they're distinctly marginal, and I'm not sure there's anything really on the market horizon to change that.
Things have been getting cheaper, yes but the absolute panel efficency hasn't got much better.
 
leezer3 said:
yes but the absolute panel efficency hasn't got much better
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My panels installed in 2015 were 14.91% efficient, you can now get panels that are 25% efficient, thats a 67% improvement in ten years. If they ever get Perovskite panels to market, that could see another big leap, although that seems to have been in the back ground for years now.
 
That's a fair point, although I was primarily thinking about the last 5 or so years, where things have definitely stalled.

(FWIW, 22.5% efficency was about in the absolute top-end commercial stuff in 2015, which actually tends to support my point)

Either way, doing it sooner is almost always going to be better than doing it later.
 
Ron-ski said:
If they ever get Perovskite panels to market, that could see another big leap, although that seems to have been in the back ground for years now.
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It's on the cusp of being available to public consumption, there is one company producing panels for solar farm, and have sold their licensing to China for production of panels. I am with you though, I wouldn't wait, not for the cost of a system at the moment, just get it done and stop worrying about the cost so much. :)
 
leezer3 said:
Just to pull that up slightly, you're forgetting the climate.

Australia (and other countries with similar levels of penetration) tend to have a much better climate for solar, which skews those figures a little.

With improvements, at the minute they're distinctly marginal, and I'm not sure there's anything really on the market horizon to change that.
Things have been getting cheaper, yes but the absolute panel efficency hasn't got much better.
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The point about the Australia was more about the impact of solar on their energy grid than the climate.

They have only really started having issues with the amount of solar on the grid a peak times (e.g. mid day) fairly recently and their market penetration is considerably higher than ours. That said they have far heavier air con usage than we do which matches directly with solar production.

One other interesting thing that people often miss with solar is that is also directly matches up wit the usage curve of EV rapid chargers. They are the most busy during the middle of the day and it tails off either side of that.
 
Mercenary Keyboard Warrior said:
Is there a guide as to what that is for?
It could be for grid sync if so I believe it will only happen occasionally just to be able to match the grid.
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from what i can tell, it's for countries that do not allow exports or for pre-paid meters that might trip (none of which apply to me) but just want to be sure before i go messing about lol
i've already set my battery to export fully before 2359, so that's an extra ~£150 year...
...but just want to optimise as best i can, if i can turn trickle feed off that will save me another £15/yr...every little helps lol

i don't want to change something that i cannot immediately sort if it gets broken, that would be disastrous :cry:
 
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As you say above, you don't need it just set it to zero.

Grid draw/export will always fluctuate a bit as equipment in your house switches on and off, or if the grid voltage changes suddenly, it takes a little time for the inverter to adjust, and it is in theory to stop export where people are not allowed to feed back to the grid, but even at 20w you'll still get some feedback.
 
Well the mob that did my initial installation finally got back to me, they won't touch anything to do with my plans for a 2nd string unless they do everything. They specifically called out the fact they didn't supply the equipment as a reason. A verbal quote of about £3k to install 6 panels on a south facing wall. Good access, little scaff needed (if any, but sensible to use scaff), very easy cable run to the inverter.

I tried to get them to quote for a 2nd string a year back at the same time as a heatpump quote, and they just delivered the heatpump quote and went quiet on the extra PV. (I didn't progress the heatpump after a heat loss survey but that's another story.)

Oy.


Reading through MIS-3002 I appreciate that there are many considerations and data that needs to be calculated and provided to obtain the MCS certification, as well as the obvious design and installation particulars to ensure it's compliant. However, there's so much in that document that the installer didn't provide to me (that I didn't know then, that I do know now!) so I'm even more irked at their response. The calcs they provided me for example bear no relation to the actual performance, I didn't get any datasheets or system layout docs prior to signing. I did get some of these once the system had been commissioned.

From that document it does seem that a Solar installer can install equipment they didn't supply when operating as an MCS Contractor for a client with a design. However I'm willing to bet me amending the existing design doc with my crayons to show the 2nd string probably won't cut it... :D


So what to do?
- Do I suck it up and shell out £3k+?
- Keep gradually accumulating shiny new PV parts in the hope I can find an installer willing to undertake?
- Or train, get MCS certified, register myself as a competant person and just do the damn thing myself out of spite? :D
 
randal said:
So what to do?
- Do I suck it up and shell out £3k+?
- Keep gradually accumulating shiny new PV parts in the hope I can find an installer willing to undertake?
- Or train, get MCS certified, register myself as a competant person and just do the damn thing myself out of spite? :D
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Is it a new inverter? Do you already ave a G99? Are you exporting at all now? Sorry if I missed the answer to these before.
 
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