Solar power calculations, please help!

[dennis]

That's not a problem the inverter will shut off if it goes over voltage, you just won't earn as much cash. Buy some storage or move your panels so they aren't all South facing.

[John Rumm]

I would much rather subsidise a nice new nuke that will provide reliable power to many people for the next 40 years, than subsidise your pocket.

[John Rumm]

So only a 38% size error in harry's memory then ;-)

[Chris Hogg]

Returning to the original post, I took another look at the numbers the OP put up, based on the results from Chris Dixon and Harry.

50,000 panels and 40 MW output. Assume the latter to be peak output, then each panel has a Wp of 800 (40,000,000 /50,000)! That's some output, bearing in mind that even CD's panels, at 1.8m^2, only have a Wp of 260. I suppose it depends on how big their panels are; probably bigger than those for domestic roof installations. To get a panel with a Wp of 800 would need a panel size of something like 2m x 3m, at Wp/m^2 values of say 133 (a not untypical value).

But assuming that's OK, that the 40MW is peak power and they use super-sized panels, how much power might they be expected to supply

*on average*? Harry's panels give peak power per m^2 of ~134Wp/m^2 (185/1.383), while CD's give 144Wp/m^2 (260/1.8). *Actual* average powers are 15.7 and 15.9W/m^2 *(see end of this thread for discussion between Harry and myself), i.e. 11.7% and 11.0% of Wp, respectively, say a mean of ~11.5%.

So realistically, that 40MWp becomes something around 4.5-5MW average, perhaps a little more depending on the type of silicon used on the panels (poly- vs. mono-crystalline).

The renewable lobby does like to present it's case in deceptively optimistic terms, hoping that the sheeple will take it at face value, which they almost always do :-(

I don't know where one draws the line between being optimistic with the truth and bare-faced lying, but I reckon they get pretty close at times.

(E&O? Blame Bacchus!)

[The Natural Philosopher]

Worse, we cant cope with 40GW of midday summer sun power without switching off all our reactors and fossil power stations, running every interconnector backwards to export the surplus, and throwing 10GW away.

Lets stop at the unholy mess 40MW causes us before adding a single new solar panel.

[Vir Campestris]

The question is - will your solar panels produce enough power over their lifetime to make up for the "cost" of manufacturing? Ditto for the big windfarms - remembering that somewhere a fossil station (or 10!) has to be kept on hot standby to deal with the windless nights.

For "cost" you can read straight forwards £SD, or you can count the environmental damage of manufacturing all those odd chemicals. Including of course resource consumption.

Andy

[Tim Streater]

None of which of course goes on harry's account. Which just confirms that subsidies of any sort are an extremely bad thing, they distort the market.

[harry]

You still haven't explained how you will deal with the nuclear waste when everyone else has failed.

[harry]

Coal and nuclear need to be shut down permanently in the near future. Only gas fired power stations are acceptable.

[harry]

Full of crap as usual. It has been up and running since March with no problems. I see you've changed from Solar PV will never do enough to it's doing too much! Brain dead.

[tony sayer]

Christ!, are you expecting serious responses to statements like that one?.

So shut them down and where is the power lost coming from?.

Answer do like the Germans are doing, import some from Nuclear powered France and so are others.

What's the cost of another 2 G/Watt interconnector cable to France I wonder;?.

A virtual nuke that is;)..

[dennis]

You haven't explained why there is a real problem.

We don't count your paranoia as a real problem that needs engineering to sort out.

[dennis]

You haven't found a way to store your renewable energy yet?

[Tim Streater]

Lying again I see harry. You've been told several times that this is a solved problem for power station waste.

[David Paste]

Thanks for taking the time to work it out. I am genuinely staggered by the numbers!

[Chris Hogg]

A generous dose of scepticism is always needed when considering the top-line data put out by renewable energy companies. Wind energy is the same, as would tidal and wave energy if it ever gets taken up in a big way. It's always worth investigating what's known as the 'load factor' or 'capacity factor', i.e. the average output over twelve months as a fraction (or percentage) of the peak output, as done here. And don't just take the energy companies' word!

[David Paste]

Oh yeah, I'm wise to the optimism factor, but after leaning about average insolation levels for the UK (1 kW/m^2 aiui), I thought maybe 200 watts average would be likely. HA HA HA!! Oh well.

[bert]

In article , tony sayer writes

And Denmark

[bert]

And how much will it cost in CO2 terms as well as operating costs to have other power stations on hot standby as the output from these renewable sources fluctuates as opposed to just using them in the first place. (esp Nukes)

[bert]

+1