Tactical Voting?

A new toy

A brief note of tactical voting: while it is true that an extra 5000 votes for the Greens in the North West would have meant Nasty Nick wouldn't have been off to Brussels, it is also true that 2500 extra votes for UKIP would have had the same effect. I also note that if the Green voters had voted for the Lib Dems, UKIP, Labour, or the Tories would have had the same effect.

Over in Yorkshire and the Humber, it's a different story: the greens would need an additional 16,000 votes. However, only 11,000 extra to Labour would keep the fascists out. If your're really prepared to do "anything"  to keep the Nazis out, Green is not obviously the way to do it.  

You can check these calculations and have some psephological fun of your own with this automatic d'Hondt vote counter that I've put on a Google spreadsheet here. 

I took the data from The Guardian's electoral maps. The spreadsheet is fairly easy to use: I've shown a couple of worked examples, and I've manually calculated the d'Hondt count for Yorkshire and the Humber to provide a check. Any bugs, please, to "a dot political dot scientist AttT gmail dot com", or to the comments section below. You are welcome to use it for any purpose you like, but if you found it useful, please would you let me know, or provide a link back to this post.

INSTRUCTIONS: You'll need to log on to Google Docs. Save a copy of the spreadsheet, so that you can manipulate in. All the data is in the first sheet ("Complete Voting Data"). Go to "Automatic d'Hondt counter" and clear the example data. Copy and paste the data you want to count in its place. After the calculation has gone through, you can read off the number of MPs the party has by going to the column marked "Round n" where n is the number of MPs the constituency returns. Happy counting!

[BTW, if you're interested in Nazi ecological policy, the classic study is "How Green were the Nazis?"]

Bring back the Oxford and Cambridge MPs?

A new proposal from Left Outside 

The title of my post is rather misleading: although before 1950 Oxford and Cambridge did used to return University MPs, they weren't elected by the students. The electorate was composed of holders of MAs, effectively a property qualification. Although abolished by an earlier incarnation of the Representation of the People Act, the seats didn't disappear until the 1950 general election.

Left Outside has an altogether more interesting idea:

But, I would like to delve a little deeper into the specifics of a new system. I would like see a change to the narrow geographical boundaries which mark out our constituencies. If a more proportional system is introduced, and lets hope it is, then I think it is time to reintroduce some quirkier features of our democracy. This is why I advocate a reintroduction of multi-member University Constituencies.

We are used to constituencies being constructed on a continuous geographical basis. For example and for no particular reason consider Newbury, Sedgefield, Dundee Westand Warrington North [1], these constituencies exist because they loosely represent the community which will elect that area’s MP. This is big bonus of the Constituency system, people are directly connected with their local representative. However, the cohesiveness of these seats also leads to them becoming safely Red, Blue or Yellow. This is bad for democracy because elections are then only really conducted in 150 marginal seats, and millions of votes cease to matter.

[...]

However, constituencies do not need a continuous area in order to be representative of those who would be its electors. There can be circumstances that link me more culturally, emotionally and politically with a call centre worker in France than a Tory Grandee in Sleaford and North Hykeham. As an ex-student, there are also very obvious reasons to believe that I have more in common with the people I eat with, drink with and study with across the country than the community I visited for 3 months out of every 12.

As a student, for 3 years (and sometimes more) half the young people in this country leave their homes and enter a new community that isn’t so much described by geography as by its “Studentness.”

These would be more representative in two main ways. First of all they would give students a say in the community to which they belong (should they choose to register there of course). Secondly, as a consequence of the reallocation of voters, local communities which the students have left will have a more equitably and fairer say in their own affairs. -[source]

I think a version of this might be very practical: but why stop at the Universities? Voters might very well have more in common with fellow union, church, or professional body members than they do with others who are merely geographically close. All constituencies will become "empires of the mind" - free associations of sovereign people. If we are really serious about abolishing the "tyranny of geography", this is the way to do it. However, we are left with a problem - most people don't have a single identity, they are former members of universities, workplaces, unions, Doctor Who appreciation societies, and so forth. In Dsquared's plan to replace the House of Lords with a House of Chiefs, everyone had to endorse one, and only one person as their Chief, subject to a threshold of e.g. 4000 signatures. I suggest you can belong to more than one constituency, provided (a) that number is less than, say, 20, and (b) you have a total of one vote, but you can divide it between the constituencies you belong (say, 1/3 to your union, 1/2 to your church, 1/6 to your university), (c) there is some threshold that a constituency needs to get a seat.

[I hope to discuss my favourite PR system, Random Dictator with Barrage, in a future post]

Council elections

A mighty institution faces the electorate

I'm talking, of course, about the Institute of Physics. The postal ballot for IOP Council doesn't close until 20 July, but don't forget to vote!

More trivially, I hope UK readers remembered to vote yesterday. Between the IOP, the Euros, and Council elections - and possibly a Convocation, depending on whether the current mess is sorted out - I really feel I have shall have done my democratic duty this year. This is fortunate, as I shan't be able to vote in the election if it's after September.

Electrobollocks

It is a form of pollution

The lads at HolfordWatch have a look at the Green party's policies. All good clean fun - and, from Neil in the comments to that piece, this little gem:

PL414. The Green Party deplores the intransigent attitude of the United Kingdom government to 

the damaging biological effects to those living in close proximity to high voltage power cables, caused by the associated electromagnetic field. This constitutes an electrical pollution. Immediate action should be taken to ensure that no high voltage cables are sited near habitation and that those that are should be re-sited as soon as possible, recognising considerable urgency.  

 

Things that I do not understand

I leave the room for 5 minutes, and someone breaks logic

I have thought about this for several hours, and I still can't make sense of it. 

We've just had a crowd of Nobel Laureates telling us all how urgent is the need to do something about climate change. And we've also just had a group of not scientists telling us that hundreds of thousands are already dying from the effects. That latter used some, umm, creative methods to reach that conclusion, for I was previously entirely unaware that earthquakes were indeed caused by climate change.

However, this leads to me to ponder a little on what Lord Stern told us. That was that we could sort this all out for the remarkably low price of 1-2% of GDP, spent year by year over the next few decades. Given the size of the UK economy this means some £14 billion to £28 billion a year. And we're also told that this amount should be used to correct the price system, so that matters currently external to the markets become internal to the pricing system. This so called Pigou taxation.

This makes sense, I have to say, as the amount of damage, by Lord Stern's figures again, done by Britain's emissions are again in this sort of range: £14 billion to £28 billion.

Now whether I actually swallow all of these numbers is a different matter, but let's take them at the logic of their proponents. We know  the problem, we know how to solve it, we know how much the problem costs and we know how much the solution costs. Excellent.

But, but....well, how much are we already paying in such green taxes? That depends a little on exactly how you want to calculate what is a green tax but adding up landfill tax, air passenger duty, the petrol tax rises from the fuel duty escalator and so on we get to a figure of....£14 billion to £28 billion again. Which means that, by the logic of the Stern Review, we've actually already solved climate change.

No, not even I think that to be actually correct, as Lord Stern himself doesn't. For he keeps telling us that we must do much more, much more quickly, in order to solve the problem, as those Nobel Laureates were also telling us last week.

Which, sadly, leaves us with one inescapable conclusion. We're not going to crack this at that low cost of 1-2% of GDP per year over the decades. It's going to be much much more expensive than that: which means we really need to reopen the calculations of whether we want to stop climate change or would prefer to adapt to it.

I am being terminally stupid, or does this make no sense whatsoever? The conclusion is not inescapable, and it's all very well raising the money thru' taxation but presumably it needs to be spent on climate change mitigation efforts to actually do something about mitigating climate change. Presumably, the money is currently spent on other things.

Have I completely missed the point? If so, could someone explain it simply and in words of one syllable in the comments?

Kissinger and the Pot Thief

Testing The Register's hypothesis

I think it was in "Years of Upheaval" that Henry Kissinger compared Le Duc Tho to a thief's defense council: his client didn't steal anything, it certainly wasn't a pot, and anyway it wasn't black. This (characteristically self-serving) anecdote came to mind on reading this article in The Register. 

The UK's climate act is "all but certain to fail" and alternative approaches should be considered, according to a new study. The act commits the UK to cut its CO₂ emissions by a third in just 13 years, and by 80 per cent by 2050.
Roger Pielke Jr is a professor at the Cooperative Institute for Research in Environmental Sciences and a visiting professor at University of Oxford's Said Business School who has accepted the case for cutting carbon emissions. However, in a new journal article he says the Act is unrealistic, setting symbolic and therefore meaningless targets instead of practical policy.

Sadly, The Register doesn't link to the actual paper, which you can read here. 

I'm agnostic on the Climate Change Act (I simply don't have the economic background to have an informed view; it's a wise man who knows what he doesn't know) but Roger Pielke's name seemed awfully familiar. Perhaps it was from here:

"I honestly don't know what the proper test is" 

or perhaps it was here  or here .

Anyhoo, I think if we are going to be advised on meeting targets, it would be better if our advisers knew how to do a hypothesis tests. 

They said it was "too cheap to meter"

Oh no they didn't

Inspired by this excellent post  from Neurosceptic, I thought I'd use Google News Archive to investigate the widespread untruth  that proponents of nuclear power claimed it would be "too cheap to meter". 

Here are the time lines for searches on "nuclear power"  and "nuclear power" + "too cheap to meter" 

In the first we can see the peaks for the Three Mile Island (1979) and Chernobyl (1986) disasters, and a steady increase from about 1995.

In the second, we can see a peak representing Lewis Strauss speech (and the aftermath of Eisenhower's "atoms for peace" speech) in 1954, a few more references during the 50s, and then a big gap until 1975, when the porky picks up popularity, although we can't see "I told you so" spikes associated with the two nuclear disasters mentioned above. There's a caveat to this - the timeline shows hits in the 1940s, although examination shows that they are from much more recent sources referring to events in the 40s. However, I think the distribution is still interesting.

 

[Sadly, one of the top hits on the second search is this from "Scientific controversies: case studies in the resolution and closure of disputes in science and technology", edited by Hugo Tristram Engelhardt and Arthur L. Caplan. The depressingly familiar quote is enlivened by a bogus citation: 'In December 1953, when President Eisenhower was promoting the Atomic Energy Act in his famous "atomic power for peace" speech before the United Nations General Assembly, he made his promise of electricity so abundant it would be "too cheap to meter" '. In the internet age, you can read Eisenhower's "atoms for peace" speech here, and use control-F to verify he said no such thing. I suspect the author is confusing the Atomic Energy Acts (the original 1946 McMahon act, and its subsequent modification in 1954) with the International Atomic Energy Agency that Eisenhower's speech eventually led to] 

Tilting at windmills

Wind turbines: grudge match

[New and irregular readers may like to read the Heresiarch's original post  and my response]

Further to our discussion about wind turbines, the Heresriach has returned to the field of battle with this post. His previous railings against the "wastefulness and illogicality of investment in wind-power" aside, he now quotes from this article  in The Times.

"Europe should scrap its support for wind energy as soon as possible to focus on far more efficient emerging forms of clean power generation including solar thermal energy, one of the world’s most distinguished scientists said yesterday.
Professor Jack Steinberger, a Nobel prize-winning director of the CERN particle physics laboratory in Geneva, said that wind represented an illusory technology — a cul-de-sac that would prove uneconomic and a waste of resources in the battle against climate change.
“Wind is not the future,” he told the symposium of Nobel laureates at the Royal Society. Instead, he said, technologies such as solar thermal power — for which parabolic mirrors reflect the Sun’s rays to generate heat and electricity — represent a more promising way of supplanting fossil fuels. “I am certain that the energy of the future is going to be thermal solar,” he told The Times. “There is nothing comparable. The sooner we focus on it the better.”"

It is worth examining this in detail, because it illustrates the ignorance and misinformation about energy generation in general and wind power in particular. 

Although Steinberger is best known for the discovery the muon neutrino, and got his Nobel for this achievement, he has a distinguished track record in particle physics. All the more disappointing, then, for him to come out with this sort of nonsense:

He said that intermittent energy sources, such as wind, required back-up power generation, which undermined their contribution to emissions reductions. In contrast, solar thermal power could generate heat energy that could reliably generate 24-hour electricity.

[To be fair, the lack of direct quotation demonstrates that this is a journalistic precis, as I can't see someone of Steinberger's stature saying anything so moronic. I suppose we should be greatful that it isn't Vitamin C , racism  or telepathy . Does funny things to people, winning the Nobel prize]

1. A note to all wind skeptics: intoning "of course, the wind doesn't blow all the time" does not make you look profound, it makes you look silly. All power stations have a less than 100% capacity load, and every informed wind advocate is well aware of it. Not also that a capacity load of 33% (for UK offshore generation) does not mean that the wind isn't blowing 67% of the time: it means the turbine isn't operating at maximum capacity, which is not the same thing.

2. Even if there is no power storage whatsoever, and the wind stopped blowing everywhere, there would still be carbon savings from using wind: back up power generation doesn't have to work all the time, so even intermittent power plants can reduce CO2 emissions (John Band made this point on the original thread)

3. These apply to solar power as well as wind: solar won't work at night, but no grown-up is going to offer that as a citisism of solar. 

From the article:

"Britain has made wind energy a priority in reducing carbon emissions by 34 per cent by 2020. The Government plans to build 33 gigawatts of offshore wind power by 2020, which the professional services organisation Ernst & Young estimates will cost more than £100 billion."

The Times does not supply a citation for this statement, perhaps because to do so would show that it isn't true. You can read the Ernst and Young report ("Renewable energy country attractiveness indices", Quarter 1-2 2008) here , and I quote from page 13:

"The lions share of the 2020 of 20% of energy generated from renewables target will have to be generated from wind, anticipated to be around 33GW of additional capacity. The plans will see an additional 4,000 onshore and 3,000 offshore wind turbines. It is expected the plans will cost the country around GB£100bn" 

Right, so not all offshore and not more than £100 billion - isn't the Old Media fantastic? 

However, now we have the accurate figure we can calculate the cost/GW of the plants. Wind power offers an additional 33GW at £100billion pounds (including the cost of connection to the grid): £3 billion /GW. The 3-3.5GW solar thermal project, claims Steinberger, will cost £20 billion (not including connection to or construction of a continent spanning undersea grid from North Africa to the UK): £5.7-6.7 billion /GW. The solar thermal plan costs about twice as much per GW. 

As the Heresiarch is concerned about the amount of land covered by wind turbines, it seems odd he doesn't calculate the area covered by this proposed solution: let's have a quick go. Suppose the energy density that can be delivered by solar concentrators is 15 Wm-2, and the putative solar power station is to deliver 3GW. This implies it will cover an area of 200km2 ! To replace the 33GW from wind power requires a solar farm of 2200 km2 - rather bigger than London . That's quite a large power station to build in someone else's country, and I am unpersuaded that the solar concentrator farm is any more aesthetically appealing than a wind farm. In addition, wind farms don't occupy the entire area around them, which can be used for agriculture or tourism. 

Now, this seems I'm a bit down on desert based solar - this is far from the case. David MacKay, who has thought about energy a lot longer and harder than I have, envisages 50 GW from solar in deserts in Plans N, L, and G (MacKay, Without Hot Air, page 208-210). Lomberg relies heavily on solar in deserts. However, there are technical challenges to exporting electricity across a continent sized distances, and you don't have to be a Little Englander to be concerned about relying on other countries for too much of our energy (problems we can see now with fossil fuels). And so we come to the Heresiarch's final argument:

"Claiming that his favoured model, solar thermal generation, was on the brink of a great advance, he said "Governments need to focus on this area right now". Continued investment in wind generation, he strongly implies, will actually harm long-term prospects for carbon-neutral power by diverting resources from where it would best be spent. Which is more or less what I said."

It's an argument I'm quite sympathetic to - although of course as a researcher, I'm all in favour of money being spent on research. 

However, the flaw is that it's an argument that can be made at any time, and it is quite resilient to evidence - research always might through up something new, which always might be better than what has gone before. Any investment in alternative energy can be rejected on the grounds that spending the same amount on research will deliver a better solution at some unspecified point in the future.

As always, it's seldom an either-or choice: there is a great deal of alternative energy research, which is quite consistent with investing in wind power as well. As wind power is undoubtedly going to be part of the mix - MacKay's plans all include more than 4% wind power - it's sensible to get building now. 

Betz' law

The proof of the pudding

Musing on the wind turbine post below,  it occured to me that the derivation of Betz' law could be made into a good class room exercise. All maths is GCSE level if you stick to graphical methods, though you can use calculus if the students have studied it to get an exact result. Some the algebra could be a bit tricky for school children - you need to use the difference of two squares twice.

Consider a wind turbine in the form of a disk, with area A. Wind traveling at a speed v1 hits the turbine, and leaves the turbine at speed v2.

Undisturbed wind flowing through the area of the turbine is 1/2 m v2. In one second, the mass of air flowing through the turbine is given by ρAv where ρ is the density of the air. 

Accordingly, the power - kinetic energy per second - in the undisturbed wind is P0=1/2 ρAv3. 

The wind speed through the turbine is (v1+v2)/2, the average of the the entrance and exit speeds.  

The mass of air flowing in one second is ρA(v1+v2)/2

The power imparted to the turbine is the kinetic energy of the wind imparted to the wind turbine in one second, P1

The efficiency of the turbine, η, is given by the ratio of extracted power to the power in the undisturbed wind

We can use the difference of two squares [(A2 - B2) = (A+B)(A-B)] to re-write this as 

We can write the efficiency as a function of the ratio R=v1/v2 :

We have two ways of proceeding: the first is to simply plot out η as a function of R, and see that the maximum occurs at just under 60% and for a ratio of about 1/3.

More rigorously, we can differentiate the efficiency with respect to R, and set the derivative equal to zero to calculate the value of R such that η is maximized. 

While we could plug our a,b, and c coefficients into the quadratic formula, a more elegant approach is to factorize the quadratic by inspection to obtain:

Taking the positive root (as the negative root is unphysical), the maximum occurs when R=1/3, and the efficiency η=14/24 =0.58 (2 s.f.)

Questions:

• What slightly dubious assumption has been invoked? Can you justify it?
• Could you confirm this result with a dimensional analysis?
• Any other suggestion in the comments.

 

If it annoys you that much, why do you read it?

Horrified fascination

Yes, it's more scienciness from Greenpeace's "Nuclear Reaction":

"So much for nuclear’s promise of cheap electricity. Do you know they once said nuclear energy would be too cheap to be metered? Stop laughing, it’s true." - [source]

No, really, it isn't. 

The myth of Richard Pike

An embarrassment for both the RSC and The Register

Richard Pike, the former BP executive turned head of the Royal Society of Chemistry, has written what Andrew Orlowski in The Register describes as "a hard hitting contribution to Research Fortnight". Orlowski goes on to claim that

"Pike says the £250m tax boondoggle designed to induce us to buy electric cars would save less than 0.01 per cent of UK carbon emissions - yet represents a third of the nation's annual budget of the science and engineering funding council."

Before going on, I feel obliged to note this is an unfortunate way of phrasing this that might easily be misread. The EPSRC budget is ~£750million this year, whereas the putative electric car program the Pike and Orlowski decry costs £250 million in total over 5 years (from 2011, when the DoT expects suitable cars will be available). However, there's rather bit problem with this, specifically that the program doesn't cost £250 million and isn't there to induce us to buy electric cars.

Pike is appalled by "woolly thinking" (as am I, although by a rather different target), warning of "a potential waste of £250 million of public money  to subsidise the purchase of over 50,000 vehicles."

 Oh dear. With 30 seconds on Google we can locate the press release on the program here: the description is "Central to the strategy is an initiative to help put electric cars into the reach of ordinary motorists by providing help worth £2000 - £5000 towards buying the first electric and plug in hybrid cars when they hit the showrooms - which we expect from 2011 onwards." We can see where Pike gets his figure from, he's divided what he claims is the total cost (£250 million) by the upper limit per car (£5000) to obtain 50,000 subsidies.

Unfortunately for Pike's argument: "This funding is included in a £250 million scheme to deliver a green motoring transformation, part of the wider Government support to help consumers and businesses make the transition to low carbon.....The strategy also includes plans to provide £20 million for charging points and related infrastructure to help develop a network of 'electric car cities' throughout the UK and an expansion of an electric and ultra-low carbon car demonstration project on the UK's roads. This project will mean over 200 motorists [!!!] throughout the country will have the opportunity to drive a cutting-edge car and feedback the information needed to make greener motoring an everyday reality." [emphasis mine, and under the circumstances pretty important]

Clearly, this is a measure with a tiny budget, to monitor what electric car drivers use, coupled with a much more expensive -and very sensible- proposal to build infrastructure and charging points. Even this last costs only £20 million over 5 years, a tiny fraction of the DoT spend.

Right, so those figures are just Pike's fantasy, as indeed is the whole "0.01%" thing, should we be any more convinced by the eye-catching claim that the efficiency of the electric car is a "myth", as is their environmentally friendly appearance?

No, I think we should not. Pike claims that, while electric cars are 3-4 times more efficient than petrol cars, the distribution of electricity from the power plant is only 36% efficient, and claim thats "the energy advantage has effectively disappeared". O rly? Accepting arguendo the figures he offers from the academic report - of 20kWh/100km and 80kWh/100km for electric and petrol respectively, this implies that accounting for his 36% efficiency, the electric car still wins, clocking in at 56kWh/100km vs. 80kWh/100km. 

What about carbon emissions? Grid electricity has a footprint of about 500 g per kWh (note we don't have to account for efficiency, as this is already built in to the carbon footprint), so 20kWh/100km implies a footprint of 100g CO2 per kilometer, comparing favourably with the UK average car 168g CO2 per kilometer (MacKay, Without Hot Air, p122, figure 20.9), unless we cherry-pick very small cars.

Note that electrification still wins, even with our present energy mix. As low carbon technologies are only going to make up a larger proportion the mix, the carbon emissions will continue to decrease. Surreally, Pike concedes that in nuclear France the carbon costs are close to zero (although a more intellectually rigorous author might have noted something about manufacture and the lithium supply).

Frankly, this is a massive FAIL for the RSC, and for the rest of us, a cautionary reminder both that an editorial in the house rag is not the same as a peer reviewed paper, and that The Register has real issues with energy policy.

Hot air and wind

The importance of numeracy

I am disappointed to see the - usually interesting - Heresiarch write a profoundly mistaken and, frankly, ignorant post attacking wind power. Now, I don't like dirty hippies any more than the next reactionary, but this is daft:

Why wind? As a giant wind-farm opens in Scotland, it should be obvious that wind power is not the future of energy supply in Britain or anywhere else. Wind-turbines are expensive and inefficient, they ruin the landscape, they are noisy when they work (which isn't very often) and they kill birds. In Taiwan, noise pollution from a wind farm has been held responsible for the death of four hundred goats. The amount of electricity they generate, even now, is negligible. It is said that the vast new Eaglesham Moor plant could potentially power the whole of Glasgow - but that is only when it is operating at full capacity, which even in a country as windy as Scotland is not even half the time.

As David MacKay would say, what we need is fewer adjectives and more numbers. Let's find them:

(i) "Oh noes, teh poor birdies!" MacKay [Without Hot Air, p63-64] notes that in Denmark, where wind generates 9% [!] of the electricity, 30 thousand birds a year are killed by wind turbines - but 1,000,000 are killed by cars! In the UK, a remarkable 55 million birds are killed by cats, and a similar number by flying into windows. If you are concerned about windmills, you must be distraught about cars, cats and windows! Unless, of course, the bird loving is just window dressing.

(ii) "but the property values by which I mean the integrity of the landscape" Didcott power-station used to have an annual open day (this was something of a holiday treat). I used to love it, being in awe of such a mighty chunk of engineering - but I don't think you could call it "landscape-enhancing". Other things you couldn't call it were "cheap" or - Carnot cycles being what they are - "efficient". 

(iii) "Which isn't often" We'll have a go at quantifing this in a bit, when we discuss the failings of James Lovelock.

(iv) The utterly surreal: "In Taiwan, noise pollution from a wind farm has been held responsible for the death of four hundred goats." Well, call me Dr. Picky, but I going to be politely sceptical about this remarkable claim. Martin at the Lay Scientist feels the same way, and is prepared to bet no fewer than two goats that the wind farms are innocent of the charge of goaticide.

(v) "The amount of electricity they generate, even now, is negligible." Albeit not as negligible as the amount of electricity now generated by the Heresiarch's chosen alternatives of tidal power and "tapping into the jet stream of the upper atmosphere"[sic].

(vi) A statement that speaks for itself:  " Geothermal energy may be even better. This taps directly into the inexhaustible energy of the earth itself, and (technicalities aside) consists of little more than a hole in the ground. It has almost no environmental costs." I think it may be time for my long-planned "Introduction to Thermodynamics" series, which will presumably drive the remaining 3 readers of this blog. I think that's the only way I can explain all the problems with this statement, although if anyone else wants to have a go they could start with defining what we mean by hot rocks, where we can drill the hole, what the rate of thermal conduction thru' rock implies for the rate that heat can be extracted, complete with a parable about aquifiers and oil-wells to make concrete the abstract.

Poor MacKay is enlisted in support for Heresiarch's argument:

Even as the new plant opens, plans are announced to expand it still further (although it already covers 55 sq. km), while over in Shetland an even more elaborate wind-power scheme is attracting increasing opposition. A BBCreport quotes Professor David MacKay of Cambridge, who said that a "100-fold increase" in wind farms in Britain would be necessary to achieve the government target of a complete decarbonisation of our electricity supply system by 2030. The only other alternative to carbon generation he mentioned was nuclear power - itself an outdated and non-renewable technology that brings with it its own problems.

Actually, were the Heresiarch to read MacKay's excellent book Without Hot Air - which you can do for free online here - he'd find out that in ALL five scenarios that MacKay sketches out for a decarbonized Britain, wind power makes contributions from 4% (plan N, WHA pages 208-209) to 64% (plan G, WHA page 210). In the book, he discusses desert-based solar power and carbon-captured - "clean"- coal as well as nuclear.

The quotation from Lovelock is puzzling for two reasons: (i) the specific claim that turbines have an efficiency of 17%, which must be a simple misunderstanding, although there are less charitable explanations. Anyone with GCSE Maths can calculate the efficiency for a disk-like turbine as a function of wind-speed , and anyone with either a bit of calculus or EXCEL skilz can show the maximum efficiency of such a turbine is 59%. This is Betz' law, for goodness sake, it's been around for the best part of a century. Now, actual turbines will show a lower efficiency than this, being made of steel rather than algebra, but Mitsubishi quote efficiencies of 40%.  Also note that the specific power of the wind increases with the cube of velocity, so you get much more available at higher windspeeds.  (Nuclear advocates like Lovelock might also recall that a nuclear power station is just a kettle, albeit a nuclear powered one: it has turbines, too, to generate electricity. Any heat engine is going to be limited by some efficiency - the World Nuclear Association reckons you can get to 50% efficiency using super-critical water in the heat exchanger) (ii)  I simply don't get his wider point. The idea that a turbine farm is sold as producing x MW of power, but only actually produce 0.17x MW in nonscence - everyone knows the difference between capacity (the peak power attainable by a turbine) and capacity load (the expectation value of the power, given local average wind speed) - at least, anyone offering opinions about energy policy should. Incidently, the capacity load of a windfarm in the UK of a good site is typically about 30%

(iii) Further, the idea you need to back up every MW of wind-power with fossil fuels is simply erroneous. Hydroelectric batteries, where surplus electricity is used to pump water uphill, and stored as gravitational potential energy, can and are used to even out the supply. As I say, the charitable explanation is that Lovelock - an extremely eminent man with something of a cult following - has not informed himself as well as his admirers might hope. 

We finish off with a fact-free smear: 

They make their supporters feel morally superior to their opponents, who can be dismissed as selfish Nimbys. The uglier the wind farms are, the more they ruin the environment, the better: for their very unattractiveness draws attention to the sacrifice that they represent. They are Gaia's temples. The clacking of their sails is like a prayer offered up to Nature to forgive our environmental sins. It's mad.

Greens may be fanatics, lunatics, anti-technology, cruel to children or bad in bed : but what has this to do with the merits and demerits of wind power? I also think persons with scientific pretentions ought to support remarkable claims - for example, that "the more [wind farms] ruin the the environment", the better Greens like them - with evidence. Also, if you're going to run with "T3h wind-farms r prayer-weel 4 Gaia worshippers" you'd be well advised not to quote so liberally from James Lovelock. 

The Yorkshire Ranter has suggested  the problem that macho techno types have with wind: it is "gay electricity". It isn't as hot as a decarbonised coal furnace, and it hasn't the appeal of mighty erections piercing the troposphere and riding the gulf stream like a cheap strumpet.

Frequency shifting a laser pulse with an AO modulator EXTERNAL to a laser

Uninteresting to non-physicists

[This is a note to myself, because I'm bound to forget it otherwise]

Acoustic-optical (AO) modulators consist of a piezo-electric transducer - to convert an electrical signal into an acoustic wave - bonded to an optical material (like tellurium dioxide, fused silica etc) which caries the acoustic wave.

The use of an AO modulator I'm most familiar with is a controllable polarizer for optical orientation experiments. Optical orientation unpolarized light to generate spin-polarized carriers in a semiconductor (to "orient" them). Control over light polarization can be achieved  with a suitable light source followed by a linear polarizer and either half-wave plate (linear pol) or a quarter wave plate (circular polarization). However, a side effect of using circularly polarized light to generate spin polarized excitons is that the electron spin couples via the hyperfine interaction to the nuclear spins, generating spin polarized nuclei. This can be a problem, as nuclear spins dephase/relax via dipole mechanisms which have much longer (relaxation T1 and coherence T2) lifetimes than electrons or holes. Carrier lifetimes in bulk III-V are usually less than 10ps compared with ~10s (!) for nuclei. This can wash out the effect you are trying to measure.

The way round this is to use an AO modulator, together with a half-wave plate, to flip the polarization very rapidly (~10kHz). This eliminates longer time effects like nuclear polarization.

The other use for AO modulators, that I've been finding out about recently, is to shift a laser pulse frequency, for example for heterodyne optical spectroscopy. The obvious way to do this would be to incorporate a modulator into the cavity and use the tunable dispersion or birefringence, perhaps together with another element to shift the wavelength of the laser. However, to do heterodyne spectroscopy, we need two (or more) coherent pulses of different frequency, so a laser pulse needs to emerge from the cavity unmolested, and then a beamsplitter(s) used to generate appropriate pulses. A pulse is then incident on an AO modulator, which is being modulated in the ultrasound region. This generates a series of compressions and rarefractions in the optical material, in effect a transient diffraction grating propagating thru' the modulator. The laser beam is refracted thru' the modulator, and deflected at some angle as expected from the diffraction grating. However, as the diffraction grating is propagating, it induces a Doppler shift in the frequency of the light (exactly as a mirror that was moving at a velocity that light was reflected off would, or as a car in a radar speeded trap does) shifting the light frequency to a higher (or lower) wavelength.  You then have two coherent pulses as a different wavelengths! Clever, eh?

Hiding in plain cite

"Nuclear Reaction": the gift that keeps on giving

The glorious thing about the internets is that you can follow up citations, and find out what someone isn't telling you. For example, take this post from Nuclear Reaction, which quotes a popular article in EnergyBiz by Dr Benjamin Sovacool. 

One recent study published in the May issue of Energy Policy looked at major energy accidents from 1907 to 2007. The major accidents were defined as incidents that resulted in either death or more than $50,000 of property damage. The study identified 279 incidents totaling $41 billion in damages and 182,156 fatalities, with the number of accidents peaking in the decade between 1978 and 1987, which had more than 90 accidents. In terms of cost, nuclear plants ranked first with regard to their economic damage, accounting for damages equivalent to $16.6 billion, or 41 percent of all damages during the past century.

Contrary to the industry´s claim that nuclear facilities are safe, 63 major accidents have occurred at nuclear power plants. Twenty-nine accidents have occurred since the Chernobyl disaster in 1986, and 71 percent of all nuclear accidents, that is, 45 out of 63, occurred in the United States, refuting the notion that severe accidents cannot happen within the country or that they have not happened since Chernobyl.

Using extremely conservative estimates, nuclear power accidents have also killed 4,100 people. The nuclear power accidents have involved meltdowns, explosions, fires, and loss of coolant, and have occurred during both normal operation and extreme, emergency conditions such as droughts and earthquakes.

Sounds scary. How odd that Greenpeace forgot to include the previous paragraph:

While responsible for less than 1 percent of total  energy accidents, hydroelectric facilities claimed 94  percent of reported fatalities. looking at the gathered  data, the total results on fatalities are highly dominated  by one accident in which the shimantan dam failed in  1975 and 171,000 people perished. 

Personally, I would have also noted that the number of people killed in coal mining accidents in China alone in 2005 was 5986, in excess of that for nuclear power in the entire period studied, in order to provide some context for the figure. 

Unfortunately, Dr. Sovacool (or his editor) neglects to give the full citation, or even mention the paper is by him, but for the partial citation in the text you can deduce that it is Sovacool, "The costs of failure: a preliminary assessment of major energy accidents, 1907-2007", Energy Policy, Volume 36, Issue 5, p1802-1820 (2008) and is available here thru' Science Direct.

Two more for the list

One from the US, one from the UK:

Vaccination (Not using) - People who do not have their children vaccinated should be prosecuted for domestic terrorism and child abuse. - [source]

SATs (UK) - The union's outgoing president, Bill Greenshields, said he was confident a boycott would be successful."We will end this child abuse," he said. - [source]

Both have been added to "In the future, everything will be child abuse for 15 minutes".

More "burning holes with light" stuff
How I love it

The Amateur Transplants destroy an Easter egg by accident. I don't think there's any lensing going on - the plastic is flat - but the point closest to the light presents a smaller surface area to the sun, and therefore recieves a higher power/ unit area. [This is the same reason that you want to locate solar cells as close to the equator as possible]. The burn through looks cool, tho'.

[via Dr. Crippen]

No, they did not.

Myths about nukes

An otherwise interesting paper is marred by this:

"Since then, Americans have dreamed of exotic nuclear 

possibilities. Early advocates promised a future of electricity too 

cheap to meter, an age of peace and plenty without high prices 

and shortages where atomic energy provided the power needed to 

desalinate water for the thirsty, irrigate deserts for the hungry, 

and fuel interstellar travel deep into outer space.‘‘carbon-free electricity source’’ (1998). Patrick Moore, co-founder 

of Greenpeace, has publicly stated that ‘‘nuclear energy is the only 

non-greenhouse gas emitting energy source that can effectively 

replace fossil fuels and satisfy global demand’’ (Environmental 

News Service, 2005). The nuclear power company Areva (2007) "

From Sovacool, Energy Policy 36 (2008) 2940-2953, emphasis mine

I appreciate it would be jolly convenient for anti-nuclear campaigners if the sinister cigarette smoking nuke-men in rakish hats had let the politicians astray with a lot of fast talk about monorails  energy which was "too cheap to meter", but -alas - it is Not True. 

The Daily Mash
On the expenses scandal

Emma Bradford, from Harrow, said: "I'd like to designate him as as my 'second MP', just for a couple of weeks, so that I can claim twelve grand to have him refurbished and then sell him to some really nasty Russian pimps."

Roy Hobbs, from Oldham, said: "I'd like to buy one of those four-slot Dualit toasters from John Lewis and spank him across the face with it so hard that I break both my wrists."

And Tom Logan, from Salford, added: "If you know that it's wrong now, then surely you knew it was wrong when you were spending my money doing up houses you bought with my money and then dodging capital gains tax even though you'd still have made a tidy profit and would, at least, have been able to return some of my money. You nauseatingly rancid lump of pox-ridden, cock-sucking pigshit." - [source]

Less laughing and more thinking

Greenpeace FAIL

I would quite like to be a Green, but this sort of rampant stupidity is quite off putting:

 

Yesterday we brought you the fantastical tale of the Brazilian government announcing their ambition to build 50 new nuclear reactors by 2050. No sooner had the disbelieving laughter died down here at Nuclear Reaction, along came the World Nuclear Association (WNA) with an amazing fantasy of its own. Wait until you see this – it’s amazing. There are comedians who would kill for this ability to make people laugh…

In its Nuclear Century Outlook report, the WNA has an upper ‘outlook projection’ of 11,000 new nuclear reactors being built by the end of the century.

Read that again. The WNA can envisage a scenario in which 11,000 nuclear reactors will be built in the next 92 years.

That means starting to build this October 120 reactors a year…

…which is 10 reactors every month…

…which is one reactor every three days.

I suppose that's why washing lines are an impossible technology: after all, if a sweater takes two hours to dry, all my laundry will take weeks... 

No-one is righteous 

Although plenty are self-righteous

6 in 10. 6 in 10. 

There is a reason Paul teaches that those who say "Do evil, that good may come of it" are condemned (Romans 3:8). 

No-one ever does evil for its own sake. The cackling Bond villain lives only in films. In the 80s, Private Eye did a spoof called "The Secret Diary of Colonel Gaddaffi", which consisted of "Monday: God up, GOD guided my breakfast, did something diabolical, went to bed. Tuesday: Got up. GOD guided my breakfast, did something diabolical..." and so on through out the week. All men in all places in all times who have committed abominable acts of wickedness didn't do it to laugh manically. They "pursue the good in a disordered way": they will the ends and ignore the means. "I was after a good end" and "I was following orders" didn't work at Nuremberg and will not work here.

6 in 10. The symbol of our faith is a torture device. How can people hear of a man half-drowned or another locked in a box with insects and think "Yes. Of this I approve. Now, I must hurry to Bible study".  

[Statistic via Ben Goldacre]