Was listening to the repeat of Desert Island Discs this morning when the eclipse started here in S London. Not very spectacular due to the cloud coverage.
The track being played?
*I'd rather go blind"
Followed by * I can see clearly now*?
For those that are interested you can see the effect most clearly here
As expected a non-event and probably a straw man raised by those who want to prove that renewable energy is really great. Its not, but this isn't why.
I am surprised it only dipped by a factor of 4 or 5 from the trend line. I measured a decrease in light intensity here of 1/16.
Actually it was a straw man raised by those trying to rubbish solar PV which does attract insane market distorting grants in Germany. They do have way too much of it installed for such a high latitude country.
On this at least we are agreed. BTW Any idea why the solar PV output didn't fall more in line with the reduced light levels?
Simple geometry suggests with a 90+% obscuration of the suns disk incident power on the ground is down by the same proportion so why did the solar PV trace not fall by a similar amount from its trend line?
Is someone running deisel powered fake solar PV arrays during daytime? (serious question)
After all that I hardly noticed through the cloud - I thought it might go a bit darker - but just another shade of overcast.
Shame - be a while till the next one.
You say there that the short-term variability in supply, as provided by Renewables, is essentially the same problem for the grid as variability in demand, which makes good sense and which I understand. As your Gridwatch admirably demonstrates, the daily fluctuation in UK demand ATM is about 20GW, from say 50GW at around 7PM down to 30GW in the middle of the night. Looking at the sources of supply, this variation is compensated for in part by coal (say 3GW), part by pumped storage (say 1.5GW), but the lion's share is taken up by CCGT (say
15GW), which ramps up 10GW over about 2 hours, first thing in the morning and another 5GW in the late afternoon, both fairly predictable.I don't see why the number of CCGT generators couldn't be increased significantly to compensate for variations in solar and tidal in the same way, using fracking gas for example. What the financial cost of running CCGT plants like this is, I've no idea. Nor do I know the benefits in terms of CO2 saving, if any, which is the raison d'être underlying the whole thing anyway.
I'll go and see if MacKay says anything about it.
perhaps as it was predicted less reliance on solar was assumed.
Nah they'd use CFL or LEDs focused on solar panels. ;-)
I think it was Spain where there was widespread abuse and the FIT payments showed there was full sunshine, 24 hours/day every day, on a widespread basis.
The problem is that building more CCGT that is operating at a lower capacity factor is simply uneconomic. Hence all the capacity payment stuff.
Have a look at Euan Mearns blog
Well no. In fact that article was written to address what Mackay didn't
- the cost and issues associated with intermittency as opposed to energy density.
Ob#vipously te problems of renewable energy can be 'solved' by destroying the whole countryside and national economy, and building lots of subsidised gas power stations and overcapacity of renewable energy..etc etc.
The point to make was, first of all would that actually result in any emissions reduction - and years later NO ONE KNOWS, and the other point was, there comes a point where, overall, even at current mad regulations-inflated prices, nucleaar is *overall* a cheaper way to reduce emissions (if you think they need reducing that is).
Ultimately load variation is a problem for conventional power stations they already have to cope with. Renewable energy just adds *more* variation. And the cost - carbon and financial - of dealing with fluctuations is as high if not higher than actually dealing with the demand.
It presumably was not 1/16th across the whole country at the same time though?
With the subsidies available, I am sure there must be a few installations where someone has worked out how to sell mains electricity back to the grid at a profit. ;-)
Is it not that the further south you go the less the obscuration, the
90%+ figure was only true for northern locations. I have been unable to find the numbers for southern France but guess that it would be a lot less than 90%
You're overlooking the financial cost of *building* them, too. Renewables means building power sources *twice*.
I had clear skies, and the fall in output as graphed seemed pretty proportionate.
Chris
Well, OK, ITYP, but really I was just exploring the idea that CCGT generators were more easily brought on stream and hence more flexible and dispatchable than e.g. coal-fired power stations, so could be used to fill the gaps in renewable energy supply at short notice. I accept that it would cost, but I'm sure the likes of Harry would say that no-one ever said saving the planet was going to be cheap. That pre-supposes that the planet needs saving, which is moot, and also pre-supposes that running CCGT power stations at reduced output would contribute to that salvation, which is also moot.
Mearns' blog for March 18th, that TNP posted a link to, makes alarming reading. Mearns summarises a recent report 'Central Planning with Market Features: how renewable subsidies destroyed the UK electricity market', by Rupert Darwall, published by the Centre for Policy Studies. Part of the last bullet point from Darwall's report is relevant: "No British government has yet to produce an analysis demonstrating renewables are the most efficient way of cutting carbon dioxide emissions."
I'm with most people here; if CO2 is really a problem, then build nuclear. It's a no-brainer, and the obvious way to go.
They are all of that, but gas is a lot more expensive than coal.
I accept
Euan is worth looking at once a week. Some interesting stuff there.
And doesn't waste the gas that will be needed for plastics etc sometime either, particularly if the nukes are done well enough so that electrical heating is the same price as using gas.
In fact methane can be made from carbon dioxide via the Sabatier reaction, discovered early in the last century: CO2+4H2 -> CH4 + 2H2O
You need to supply the hydrogen though, probably by electrolysis of water using nuclear-generated electricity! More here
Polymerising the methane gives you plastic feedstocks.
Makes more sense to start with coal or natural gas if the crude oil is gone.
And that is just one of the reasons its better to use coal or natural gas.
probably by electrolysis of
No, nukes can generate hydrogen directly.
More here
Sure, but it works a lot better to start with coal or natural gas.
Pretty close. It was probably closer to 1/10 across the whole country taking an average across the timespan and geographic diversity. The phase difference between Cornwall and Faroes wasn't massive.
I suspect this may well be the case. ISTR It has happened in Spain.
Yes. Italy is also suspect as well on that score.
TBH a co-operative neighbour and some dummy solar panels is all you need. Simply get a small but real solar installation, then take some of next doors electricity, rectify it, smooth it and add it to the real solar panel output and you can arbitrage 'fossil' electricity bought at
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