Solar power calculations, please help!

[John Rumm]

I would bury it in your garden.

[John Rumm]

If you think about it, most panels are less than 15% efficient, so

150W/m^2 would be a top end in full illumination... and that is before you factor in the realisation that more than half the time its dark, and most of the rest is overcast.

[John Rumm]

Both are true, it will never do enough, and when it does anything its usually too much at the wrong time.

It most certainly is.

[Chris Hogg]

I see today that the govt. are withdrawing the subsidy for small solar farms of up to 25 acres in area by 2016 (not sure if that includes domestic installations)

. A spokesman for the industry said on the radio that the UK had installed 8GW of solar capacity over the last few years and it was making a significant contribution towards a low-carbon economy. Assuming that 8GW is a maximum figure, and that the 15% figure estimated here for actual annual average applies, then in reality solar contributes 1.2GW on average over the year, i.e. about 3%, assuming an average UK demand of ~40GW.

The consumer will benefit in two ways: he won't have to subsidise an otherwise uneconomic industry, and he won't have to pay for the inefficiency of keeping base-load generators hot-spinning for when the sun don't shine.

[dennis]

Stop being so optimistic, most panels aren't fitted to sun trackers so only generate full power for a small period when the sun is due south(ish).

This is one of the problems people like harry cause because they are greedy and only put the panels due south so they can get maximum FITs.

It really needs the FITs changing so people that put them at other orientations get paid more to spread the peak out during the day. This would help the grid a bit.

[Chris Hogg]

I have no doubt that the renewables lobby could give you figures for that, but I wouldn't trust them in the least. I've also read that there is actually no reliable way of calculating how much CO2 is saved, simply because of the complexity of the supply system with its variety of base-load generators (coal, gas, nuclear, imports etc), all with different emission rates of CO2 per GWh of electricity generated. I've even seen it suggested that renewables could actually increase net CO2 output.

Etherington's book, 'The Wind Farm Scam'* has some useful information, especially in his chapter 5, 'Do wind turbines abate carbon emission?'. I think it's fair to assume that what goes for wind farms also applies to solar and any other form of intermittent renewable.

• new from Amazon or more cheaply S/H

[harry]

Drivel. Most people have them on the house roof and have no control of azimuth. I have seen some pretty ridiculous installations. I have a neighbour who has them facing both East and West, ie both side of her roof. There is a 15% reduction in total output if the panels are Eat/West facing.

Solar PV curve matches the peak load of electricity demand for commerce/industry.

[harry]

You fit the category nicely. They NEVER do anything and then suddenly they do. Which is it?

[harry]

It's in the pipeline shit-fer-brains. EG:-

[Tim Streater]

I notice the paper was submitted two years ago. Commercially available, installed, and able to run the grid for days yet harry?

[John Rumm]

Both you dim sausage...

In the grand scheme of things, the useful contribution to fuel saving and CO2 reduction is the cube root of FA.

However they can splurge some juice into the system in the middle of the day just when some poor power station operator could be selling their electricity.

When your solar system has enough viable storage that it can act as a dispatchable generator at least 24/7 for a substantial part of the year, and is attractive to an operator and investors to build based on the expected return on sales of the electricity sold at the market spot prices, you may have something worth discussing.

[harry]

Still drivelling on...

People like yo are the main problem.

[newshound]

As Walter Marshall pointed out, I wouldn't mind burying it in *my* garden as long as I had a heat pump too.

[bert]

So is the large hadron collider

[bert]

I see I'm being undercut. I offered a large hole in my garden for a couple of million.

[Chris Hogg]

Failing that, try one or both of these

[John Rumm]

Indeed you are...

Yup they confirm part of what I said - the cube root of FA bit - total contribution to the UKs electrical generation - just over 1%

They neglect to mention how much carbon emissions were reduced by (probably because they were in reality increased!)

They also fail to address the non dispatchability of the power generation.

Yup sorry harry, you keep spouting eco clap trap, and people like me will keep drawing your attention back to the truth. I know you are allowed your own opinion, but you are not also allowed your own facts.

[newshound]

IIRC if we shared out the vitrified waste it comes to an aspirin-sized piece each, not much good to anyone as a heat source. I see the Government flogged off Admiralty Arch to a hotelier, perhaps there is a market opportunity here.

I think James Lovelock already put in a bid too.

[bert]

Ah yes but the greenies are convinced it's dangerous hence I offer them a really really deep hole for £2m quid.

[David Paste]

I had no idea about that bit!