Solar panels and payback

Taking the OP's figures, would suggest an inverter for my system rated at 1820 kW.

My data is based on logs from my system. From a histogram of actual output, I am able to see the peak of the 3.5 kW I already quoted. From that same data I can see that around 15% of the time it is generating it exceeds 1800 kW.

Chris

There was a "moment" shortly after the installation when I wanted to see if I could run a bigger inverter and put up to 20A rather than be restricted to 16A just to prevent "clipping" in peak summer.

DNO visited to take a look and I made the excuse that I had to open the garage from the inside for access as all the floors were up in the house... Quickly plugged in a 3Kw I.R. heater and put the washing machine on so when he was given access to the meter it was going in the right direction. Only way he'd let me exceed 16 Amps was to have 3-phase installed, so we left it as it was and I kept the happy-meter. It extends my "summer" by about a month as the summer build-up is consumed. ;¬)

AIUI domestic inverters are not allowed to run "islanded" - without any external feed.

Andy

Mine does - and did for a sort time in the summer. Mind you, the switch is "break before make"

Just noticed this reply . . .

I wouldn't mind seeing the figures that support that, er, hypothesis. And it's not just a switch, when the sun goes down, solar stops. Many systems have batteries for example.

Of course. I don't see a problem with that.

I export a fair chunk - about as much as I use - at less than I pay to import. So there is some benefit to you lot, my pleasure etc.

Anyway, there's bound to be some transitional costs. You feel they're unecessary or excessive because you don't appreciate the benefits.

I had a 6 kW system installed in July last year. No batteries.

Yielded 6.25 MWh in the first 12 months. Earned £695 flogging the surplus back to Octopus (at 15p/unit) 'Saved' £306 in electricity I didn't need to import.

So, a Grand in a year. System cost 7k, so a 7 year payback

Course they are.

Switch off the dead incoming volts and switch over to your wown

-- If you tell a lie big enough and keep repeating it, people will eventually come to believe it. The lie can be maintained only for such time as the State can shield the people from the political, economic and/or military consequences of the lie. It thus becomes vitally important for the State to use all of its powers to repress dissent, for the truth is the mortal enemy of the lie, and thus by extension, the truth is the greatest enemy of the State.

Joseph Goebbels

Nothing like enough.

All the batteries on teh grid might keep it up for a minute or two at best...

That grids infrastructure costs money, and its the consumer that pays,.

No there isn't. Whaty you export is as expensive or more expensive than gas coal or nuclear WE PAY

There are no benefitrs. Only costs

Market rate for gas power is about 5p a unit.

'Saved' £306 in electricity I

If the mains dies my inverter shuts down so it can't shock anyone fixing the supply.

It should be isolated.

This increases costs. It means the grid is bigger than it need be. Just like those who advocate a tidal barrier (such as in the Bristol Channel). When it's pointed out that 4 times a day, this produces no powwer, they just say - well, build another in anti-phase.

My riposte to that is to point out that you've just built two power stations in order to get the output of one, which is a waste of society's resources. A bit like the Soviets - they were unable to build reliable kit (e.g. planes) so they just built many more than needed and kept some as spares. Of course if the books are a state secret, then it's easy to cook them

Which is also why continental railways sometimes seem cheap - subsidised and the accounts are not your business, chum.

There is an isolator switch for servicing the inverter or panels but the inverter shuts itself down if the mains dies.

You haven't mentioned whether you have battery storage? Unless you do, there's not much point in your house power staying on, only to go off when the next cloud rolls past. Hybrid inverters can isolate from the grid and carry-on (with reduced output).

It's not a waste if you consider the wider benefits. For example, environmental, and socio-economic (help with fuel poverty say). I obviously accept that you and others don't buy that argument, but we can both agree that it's there.

I'd guess there's some crude economic benefit to not producing any more carbon-intensive or nuclear energy generation - would a solar/wind array be cheaper in capital and revenue terms at actual (not SMR-imagined) prices?

It just seems staggering to me - watching the vast sums of money being pumped into not actually producing any nuclear power at all. Just scoping and getting rid of waste.

They might also be cheap because they're properly maintained, relaible, popular, don't need to make any profit, and don't rely on massive government subsidies to keep shareholders happy.

Now we have track ownership re-nationalised and train operating companies heading the same way, presumably subsidies can go away and journey costs be directly reflected in ticket prices?

I'm not quite clear about what your inverter does if it only works when there is mains.

Building two power stations where one will do seems to me to be an un-benefit.

The solar/wind array will need backup, in particular for the winter periods of high pressure when there's no wind anywhere. Solar produces zero under these conditions. Now, what are you going to use for backup? Oh dear, another situation where we build two sources of power to get the output of one. Why not just build the nuclear in the first place. SMRs, in particular. And the nuclear stations last rather longer than wind farms, especially off-shore ones.

Scoping is hardly the fault of the nuclear industry. It's due to the lies spread by greenies which cause ordinary people to panic over nothing.

Waste is a solved problem and has been for years.

Something that doesn't need to make a profit, as you put it, can be relied upon to be inefficient. And prices are set low because of subsidies with no oversight.