Solar panels and payback

I'm antagonistic for the reasons given, which may well no longer apply. However, what we see in the media and also from MilliBean is that all his new solar investments will solve our energy production problems and "power thousands of households". Statements of this nature tend to mislead people.

We're on the end of a rural 11kV, so a small system here, with battery, ought to be able to cover the short outages we get here, too.

Whilst I agree with your sentiments I really would like to know where you have found a guaranteed 10% minimum return on capital.

In the past solar has been taken up by those who can afford the initial outlay (with the subsidised discount) and have benefitted from generous FIT payments.

As there is no magic money tree it seems to come as a suprise to some that the money for all these subsidies came from the (mainly) undisclosed green tax on all our utility bills.

Solar hasn't helped low income households but the exact opposite. The well off have had the disposable cash to invest in solar, albeit made cheaper with subsidies, and the poor (and the rest of us) have had to pay for it with higher utility bills.

The same appears to be happening with heat pumps for domestic central heating. However, in my opinion, there is also a problem with the mis-selling or mis-advertising of ASHP when the changes to the rest of the heating system are ignored. A lot of fly by night companies selling ASHP suggest a ASHP is just a simple swap out for a gas/oil/LPG boiler. They are more interested in getting their hands on the grants rather than doing decent job.

Precisely the points I was trying to make.

The mere existence of intermittent flows on the grid increases system costs for *everyone*

Your solar panels force some gas station to operate inefficiently because when you are generating, overall demand diminishes, and at sunset demand leaps up more than it otherwise would, so the gas station has to be fired up from cold, incerasing emissions and costs. Your solar panels force grid infrastructure to be built to deliver it when you are not generating. So the power companies are delivering less chargeable units for the same grid overheads.

So electricity prices have to increase. For everyone *else*.

Its very simple. Every six months or so I review a set of tradeable funds I have investment in, and if they are doing less thabn 10% , I sell them. I then look for any exchange tradeable funds that have delivered more than 30% annually over the last three years and buy them..

The point is neither I, nor the fund managers I effectively employ, keep their money in one place.

And some of them buy options and get even better returns in a rising market.

Its a lot less work than 'working' or installing solar panels

I probably make about £20,000 a year for about 4 hours work every 6 months

But you cant just leave the money there. Sectors go out of fashion. Tech funds made a lot during Covid. Now energy funds are doing well.

And there exists another possibility. Buy gold.

That's gone up 900% in the last 20 years. Dunno what the compound equivalent rate is with that. Probably exactly the same as inflation...they say a loaf of bread costs the same in gold as it did in roman times...

If you stick your money in a deposit account, then the bank gambles at the financial casino with it.

And inflation eats into it.

I'd rather trust a fund manager with a proven track record on 1% commission to do that.

One that I can fire online in ten seconds

My inverter and panels show no loss in performance after 12 years so far.

It is getting interesting; if I just consider the PV panels and inverter we fitted 18 months ago to a house with a much better aspect than mine it came to £7k, at current Octopus rates if the generation were exported the return on the 5MWh/annum generated would be £750, that's 10.71%, of course you never get to draw your capital out but what the hell, I would never have spent the money.

In fact with an additional £4k for 10kWh battery and £1k for EV charger it is looking better, the arbitrage on buying electricity to charge car and battery and selling during the day looks like it is running the car and house for free and covering standing charges for gas and electricity. How long these rates will last is a bit of a guess and what amortisation per kWh for storing in the battery is debatable but I'm unlikely to outlive the battery.

That's right

My way of thinking too so I have been pleasantly surprised with both installations

My 4.6 kWp panels were installed end of 2015 and cost just under £7500. Factoring the FIT payments and 100% usage of everything produced, it broke even in June 2021 and as of end July (2024) it's returned a profit of £6200. No electricity is "wasted" on unnecessary stuff done for the sake of trying to use excess energy, it's all used on regular day-to-day usage, same as having a large 100% efficient battery but without having a battery!

And crashed badly in 2022, and again in August 2024.

Scottish Mortgage lost more than half its Nov 2021 value by May 2022.

Just about the worst thing you can do. Zero interest and storage charges on top. Better to buy Black Rock funds.

Only because Gordon Brown signalled his intention to sell the UK gold stocks back in about 2002, whereupon all the fast movers like JP Morgan short-sold gold and forced its price down to a historic low point and then bought our gold at massive discount.

Any one who used Lettuce Monday to buy gilts will have locked in a 5%+ yield, and if held to redemption, would make a nice tax-free capital gain too.

Your money may have underperformed for a while before you make that decision.

Buy those FITs last 25 years and the earlier ones are RPI linked !. This should never have been done, when most other things have shifted to CPI linking.

Just to be clear, are you saying that you manage not to actually export any energy at all?

Chris

JAAMOI, if the FIT payments were not factored in, what would the payback time have been, and what profit would you have made?

These might be useful figures for anyone thinking of installing such panels now that subsidies have ended.

And you never send us all christmas cards ...

Not really, because the costs of materials and the costs of energy have changed massively.

When I did this calculation for the wiki 2 years ago:

So you have to do the numbers based on your costs *now* and your projection of the price of energy in the future.

"Past performance is no guarantee of future results", as they say.

Theo

I do export everything un-used to all the neighbours in the area and then they give it back as and when my demand exceeds production. The very reason I'll never have a smart meter, my mechanical meter doesn't have a backstop. Don't know what year they started fitting them but the date on my meter says 1984.

Not "electricity theft" as I'm paying the going rate for every kWh used in excess of that which I am supplying.

Far more fair than the trillions of government contracts handed out to "chums" for backhanders and bonuses.

I do, every year, a card to everyone not in my PLONK filter.... about 6 of you that'd be. Perhaps Royal Mail subcontraced card delivery to Evri... I expect your neighbours had it or it's still behind a bush in the garden.

;¬)

I also wonder with the ever declining price of panels and presumably inverters, what the average lifespan of current products is.

All mine would take would be a failed inverter and cost of replacement would significantly reduce the R.O.I.

Quick worked example:

Suppose you have a 4kWp system. Peak generation in midsummer is about 500W per kWp (in the UK midlands at optimal southerly orientation):

That inverter is going to cost you £165 inc VAT (which you may not need to pay, but we're being pessimistic). Let's add £100 labour for installation, total £265.

So your inverter replacement is paid back within 8 months, on a pessimistic estimate.

Theo

If I read your reference accurately, I believe it is giving the _average_ peak generation.

My 3.64 kWp installation gives a peak output of around 3.5 kW, so a smaller inverter would be wasting some of my output.

Chris