Thursday, 20 December 2012

You Against The Professors: A Challenge

Shale gas has greatly discomfited Greens (and Gazproms) everywhere, but their sleepless nights have been fruitful and they have launched a new "argument". If you haven't seen one of these little jolly little fallacies scampering around you probably think I am kidding; but no. Here, for example are Profs David Knight (structural biologist/ biophysicist) and Robert Whitmarsh (ocean and earth science), writing to the Grauniad.
 "The reduction in CO2 emissions resulting from the switch from coal to gas in the US has been entirely offset by the export of the coal saved". 
It gets worse because, carried away with the point they consider themselves to have scored, they go on: 
"A similar argument can be applied to the UK, as North Sea oil saved by burning shale gas in place of gas will not remain in the ground". 
I could just about conjure up a highly improbable scenario in which one or both of these could logically be the case, but I see no prima facie evidence for them. A huge amount of complex empirical analysis would be required to ascertain the truth of them, not to mention wrestling with labyrinthine counterfactuals, none of which has been carried out by them or anyone else - certainly not the flawed Tyndall Centre work they call in aid, which demonstrates nothing of the sort (though it sort of hints in that direction as a possibility they'd like to believe in - and even then, they only suggest that half of the US coal might have been involved in this way).

So here's the challenge. Assume a world where coal-burning emits 2 units of CO2, gas 1 unit, and renewables 0 units. What would need to be the case for the profs' assertions to be true? 

Bonus question: what would they say, do you imagine, about the fossil fuels displaced by renewables - where will they go ?



Blue Eyes said...

I suppose he is right in a world where energy demand outstrips supply. There will always be new demand for oil/gas/coal to take advantage of the lower prices brought by an increased supply.

hovis said...

A Scientist talking utter bollocks and hiding behind credentialism - tell me it's not true! Sureky that's never happened before? You'll be telling me doctors lie next ...

dearieme said...

Full marks for the bonus question.

Budgie said...

ND, it's a state of mind achieved by statists, greenies, socialists etc. They just salivate at the prospect of control over their fellow human beings. Ask them who is using all the horse dung displaced by the use of cars?

The assumption that Renewables emit 0 units of CO2 is false. Renewables, like Wind and Solar, need constantly available backup, often Gas ticking over inefficiently. So Renewables emit the same as Gas, ie 1.

Anyway the whole CAGW thingy is based on non-sense and non-science. Of course there has been global warming in the Holocene - otherwise we would be in the middle of an ice age. Of course there has been global warming in the last 150 years as we have recovered (naturally) from the Little Ice Age.

Is there imminent catastrophic man made global warming? - there is no evidence for it. Is there any man made global warming? - there may be a minor influence but it is unproven and far from being catastrophic, and could be cooling due to aerosols.

The CAGW proponents dire predictions have not materialised in their own stated timespans.

Bill Quango MP said...

There's something so very luddite about the greenies.

When they were 'friends of the earth' it was all about smog and acid rain and if we don't close down all factories we'll all die. Seas will become irradiated. Lakes polluted...etc.

Now, that may have been true IF there had been no improvement in emissions or changes to allowable pollution or ways of manufacturing items and so on. In the end, acid rain is something found only in Blade Runner.

More recently when Saddam opened the pipelines into the gulf, we were told all life would be ended there forever. the worst ecological disaster ever.
Today, its fine.

The greens seem determined to believe that all rising data is continuous. Ie, there was 1.3 cars / household in 1965. Today its 2.1 cars. So in 2050 it'll be 4.8 cars / household.

Yet they seem not to ever include improvements in technology and use of power and also alternative 'non renewable' sources of power. Such as Shale.

They are doom mongers.

Elby the Beserk said...

Did you see this, Nick...

Précis - wind farms are not what we are being told they are

Nick Drew said...

BE - will always be new demand for oil/gas/coal to take advantage of the lower prices brought by an increased supply

there may be more desire - eg for electricity in much of India - but that's not the same as economic demand, which for energy is famously inelastic (though not zero), and in electricity is
usually constrained by capacity, not availability of fuel

lower prices will only work through to higher demand over a long period of time, and even then you'd be pushed to claim it was one-for-one with the displaced coal

hovis - amazing, I know, but seemingly true

dearieme - yes, funny, isn't it?!

Budgie - I must pick you up on one thing, which Dellingpole and Booker also keep saying and it's quite wrong. Wind + gas does not emit the same CO2 as gas alone, it emits less. The gas-fired plant moves onto a less efficient mode, but it isn't remotely enough to offset the nearly-nil CO2 of wind

(of course there are loads of other hidden costs of wind, and CO2 from their manufacturing and installation etc etc - but that's another point)

Bill - yes, luddite, leftist, irrational, and profoundly pessimistic about technological advance

oh - and very keen on redistribution

Elby - yes I did but thanks for sticking up the link

yet another of those hidden aspects of wind

Budgie said...

Come on, ND, think about it logically. You know that the load factor, on average, for Wind is around 26% (DECC figures, onshore). That means 74% of this nominal electricity output is obtained from Gas (at best) back up. That's about 0.74 CO2 in your invented Coal=2, Gas=1 scale already.

However for the 26% of the time that Wind produces, the Gas back up is still running in the background inefficiently. Say half for CO2, making it 0.87. But it is actually worse than this. Have a closer look at that 26%.

On a still, cold winter's day Wind might provide as little as say 3%. So extra Gas gets used to offset the paltry Wind, so extra CO2 is produced (bringing the figure to 0.97).

Conversely on a warm windy day Wind might provide as much as 50%+ of its nominal capacity (to get the 26% average). But the CO2 does not taper off in proportion since more back up Gas is at idle, meaning greater inefficiencies and higher CO2 than you would expect (0.5 + (½ x 0.5) = 0.75).

In both these scenarios more CO2 is generated than is first apparent so giving a figure of around 0.9 which is as near 1 as makes no real difference in such a crude scale as you sketched out.

Budgie said...

I must get out more.

Nick Drew said...

Budgie - we all know the CO2 reduction isn't what the greens would like you to think (using your numbers, 26%). But it isn't zero

there are many walks of life where a 10% reduction wouldn't be equated to 'no real difference', given the reference-point is (again, your numbers) 26%

Putting a bit more detail onto your numbers, BTW ... when efficient gas plant (CCGT in inflexible mode) moves into non-baseload operation, there is a progressive reduction in efficiency, followed by a step-change when it switches to OCGT mode - i.e. jet-engine (flexible) mode

illustrative numbers: 58% efficiency at baseload - but almost no CCGTs run that way, because night-time prices are so low. High load-factor efficiency 55%; lower load-factor but still in CCGT mode 50%; step down to OCGT, say, 45%.

So: Base case, 1 unit leccy from CCGT @ 55%, CO2 = 1

Wind case (a), 0.74 unit from CCGT @50%, CO2 = 0.74 * (55/50) = 0.81

But perhaps it needs to move to OCGT, in which case 0.74 * (55/45) = 0.9 (same as your number)

So 0.81 or 0.9 ? Everything depends on (a) how much wind in the fleet and (b) what else in the fleet. If hydro (e.g. access to Scandinavia), then things get directionally easier. If solar / nuke, things get worse. Of lots of wind, things get worse.

So - somewhere between ? Obviously a 12-15% reduction isn't a 26% reduction. But it ain't zero, and I think you damage your argument by sliding over the details.

I should get out more, too - back to the Round The Horne CDs !

Budgie said...

My you are picky. I conceded about 10% (0.9 on your scale) where you are arguing 12% - 15%. Bearing in mind that none of these figures are precise, and that your scale isn't either, there isn't much difference between us after all. Imprecision accepted, rounding to 1 follows.

My point was that Wind is not zero CO2 emission but, at 0.9, much nearer to Gas on your scale (Coal=2, Gas=1). The difference in CO2 is minimal, and UK power requirements so small in global terms, that it is not going to make the difference between Global Warming catastrophe and nirvana. And it will virtually double our capital costs (Wind plus Gas back up) for that sector.

Nick Drew said...

Actually My 0/1/2 scale was an avowedly simplistic model, purely for the purpose of having a go at the Professors

I'm not going to let the other point go though, (festive season or not) because you are blurring an important distinction and the imprecision harms the 'anti' case

it is not the wind that is 0.9 (or 0.85 etc), it is the total generation fleet with wind having replaced some gas.

Wind advocates would like to claim 0 on 'their 26%', i.e. a 26% overall reduction: but they can properly claim a 10 or 15% reduction (only), which would be wind = 10/26 (0.38) or 15/26 (0.58)

of course this is indeed a grotesque waste of money but hey, let's be accurate out there