Science – Page 108 – a sibilant intake of breath

Peak power, storage, and renewables

One characteristic of electricity poses severe challenges both for the drive towards lower carbon emissions and towards more power based on renewables: the fact that supply must precisely match demand at all times. On account of this, power plants are divided into two categories – base plants, which constantly provide the amount of power normally demanded by homes and businesses, and peaker plants, which provide some extra juice when everyone decides to turn on the air conditioning at once.

The first reason this is a problem is that peaker plants are much less efficient. It is costly to build an efficient oil or gas plant, and it just isn’t worth it to do so for one that runs relatively rarely. The second problem is more to do with the inconsistent nature of renewable power; the wind does not always blow and the sun does not always shine. As such, we need enough on-demand energy (usually based on fossil fuels) to fill the gap between what windmills can produce at time X and what consumers demand then. Plants on standby may not use much fossil fuel, but maintaining and operating them uses resources in a way that makes renewable options less appealing than otherwise.

The answer is obviously energy storage. We can build dams with two reservoirs, one uphill from the other. When power is in excess, we can pump water from the low reservoir to the high one. It can then be passed through turbines at times of peak demand to recover energy. Apparently, this can be done with efficiency of about 85%. Other options along these lines would be to have clusters of offshore wind turbines that use electrolysis to make hydrogen from seawater. That can be piped or carried to shore and used to produce carbon-free energy.

To me, it seems like another option is to use technology and incentives to help moderate power demand. If there are industries that can use a lot of power or a little, switching easily, then should be encouraged to become part of the swing capacity. It may even be worthwhile to store energy as heat in sinks or as kinetic energy in flywheels. If houses could heat or cool a block of material at the time when power is cheapest, then use that potential for heating or cooling across the day, we might need less peak capacity.

Some kind of competition for inventing fossil-fuel-free peak-power solutions may well be in order. If the technology exists, and there is enough of a cost differential between times of highest and lowest demand, it may well transpire that infrastructure can be built to normalize power demand on the scale of days, or even weeks.

The Khazzoom-Brookes Postulate

Reading through George Monbiot’s Heat, I encountered the idea of the Khazzoom-Brookes Postulate for the first time. The postulate relates to the effect of increasing energy efficiency on total energy usage and holds thas as the energy efficiency of industrial processes increases, total energy use actually rises as well. While initially counter-intuitive, the idea does seem to have some validity. If the energy cost of producing one tonne of aluminum falls from $5000 to $4000, you would expect aluminum companies to produce more. After all, their profit margin will have widened, all else being the same. The Celsias blog cites another example: if Boeing’s new 787 Dreamliner is 20% more fuel efficient, that just means that ticket prices will fall and more people will fly. Greenhouse gas emissions will stay the same or rise.

As Monbiot acknowledges, the postulate is controversial. It is certainly decidedly inconvenient for all the people who trot out ‘increased energy efficiency’ as the first (painless) means to combat climate change. Increased energy efficiency may be great for various reasons of convenience and enjoyment, but the postulate and accompanying logic does give one reason to doubt whether it can have a positive effect on reducing greenhouse gas emissions.

Sustainability and the Prius

One way or another, the Toyota Prius. is a symbolic vehicle. For some, it symbolizes how saving the planet can be relatively painless, enjoyable, and hip. You still get the same basic thing (the ability to zip around in a car) but without the guilt and with the important ability to lord it over the less environmentally responsible. Alternatively, the Prius is a symbol for the superficiality of the environmental commitments most people are willing to make. Seen in this way, it reveals how environmentalism is mere tokenism in many cases.

There are two arguments here which frequently become confounded. One is a first-order question about the ultimate sustainability of different energy systems. Is it sustainable to run internal combustion cars using cellulistic ethanol? What about plug-in hybrids charged using big nuclear fission plants? The answers to these questions are ultimately knowable to a high degree of specificity. For any given level of technology, answering them is simply a matter of applying chemistry and physics. The uncertainty therefore lies in estimations about what will be technologically possible at X or Y time.

The second-level argument is much more heuristic and intractable. There is the fundamentally liberal belief that environmental problems can be tackled fairly painlessly through a bit of cleverness and some new hardware. This is a view that takes the Prius as a positive symbol. At the other extreme is the conviction that only massive sacrifice can generate sustainability. The vision in Fight Club of people in rags pounding strips of leather on an abandoned superhighway captures this, and adherents would surely dismiss the Prius as a pathetic fig-leaf.

The latter argument seems to generate a lot more heated discussion, largely because the real meat of analysis on the former question lies in territory where most people cannot hold their own (who reading this could really calculate the efficiency of an energy grid based on photovoltaics, or of an industrial process for ethanol production from cellulose?). The latter debate requires only a will to participate, though it may not do much to leave us with an understanding of which view of the Prius is justified.

Responses to climate change scepticism

Thanks to a tip off from a new friend, I found this comprehensive collection of rebuttals written by Coby Beck and featured on the Grist website, which is itself well worth a look. The articles are sorted as follows:

Stages of Denial
Scientific Topics
Types of Argument
Levels of Sophistication

Whatever your beliefs, and whatever the case you want to make, you will find some points to engage with here.

Life improves with feta

Tonight, thanks to the cookbook Hilary sent me ages ago, I learned that a very nice pasta sauce can be conjured from onion, garlic, olive oil, basil, green beans, and nice tomatoes. Of course, what makes the whole dish work is the addition of little chunks of feta cheese on top at the end.

In Ottawa, I am planning to undertake several forms of self improvement. Better cooking is certainly on the list, as is rehabilitating my French. I am pondering whether taking some environmental science courses at Carleton or the University of Toronto would also be both possible and desirable. I would love to know more about climatic science, as well as the sciences more generally. Those who feel similarly may find this explanation of the difficulties involved in galactic colonization to be an interesting read.

James Burke’s Connections

I have mentioned it before, and may well mention it again. James Burke’s Connections is a television series worth seeing. Each episode wanders through history from one invention to another, with fascinating asides along the way.

As of this evening, someone put a stack of them on YouTube. The series was made at taxpayer expense by the BBC, so there is really no reason for which it shouldn’t already be available online for free. Watch a few episodes and you will learn a wealth of interesting (though often very esoteric) facts to break out at dinner parties.

As is generally the case when I am busy and need to come up with a blog post idea in a hurry, this was yanked from MetaFilter.

PS. By the end of each exam, I was coughing my lungs out. Now, I am taking little sips from my bottle of nasty tasting (and ineffective) cough syrup every three hours or so. Now, I feel like I have an especially nasty cold, with all the ill effects involved therein.

Haemodynamically responsive

How risky is climate change?

On his blog, Lee Jones posted a link to this book review. Basically, the argument is that people are (a) exaggerating the dangers of climate change and (b) using climate change as an excuse to pursue other ends. I would not deny either claim. The Intuitor review of The Day After Tomorrow is evidence of the first, and more can be found in many places. Of course, their review of An Inconvenient Truth suggests that not everyone is guilty of misrepresentation. As for smuggling your own agenda into discussions about climate change, I suspect that is equally inevitable. The question of how to behave justly in response to climate change is fundamentally connected to the history of economic development.

In an unprecedented move, I feel compelled to quote my own thesis:

While the IPCC has generated some highly educated guesses, the ultimate scale of the climate change problem remains unknown. On account of the singular nature of the earth, it is also somewhat unknowable. Even with improvements to science, the full character of alternative historical progressions remains outside the possible boundaries of knowledge. As such, in a century or so humanity will find itself in one of the following situations:

Knowing that climate change was a severe problem, about which we have done too little

Believing that climate change was a potentially severe problem, about which we seem to have done enough

Believing that climate change was a fairly modest problem, to which we probably responded overly aggressively

Observing that, having done very little about climate change, we have nonetheless suffered no serious consequences.

Without assigning probabilities to these outcomes, we can nonetheless rank them by desirability. A plausible sequence would be 4 (gamble and win), 2 (caution rewarded), and then 1 and 3 (each a variety of gamble and lose). Naturally, given the probable variation in experiences with climate change in different states, differing conclusions may well be reached by different groups.

As such, what it means to make informed choices about climate change has as much to do with our patterns of risk assessment as it does with the quality of our science. Exactly how it will all be hashed out is one of the great contemporary problems of global politics.

Scientific progress goes boink

When I was in the process of applying to Oxford, I filled out a web questionnaire about stress. A few months ago, I was invited to participate in a study and given a two-hour screening. Today, the active part of the experiment began. I know it involves mood and stress, but I don’t have a terribly good idea of what they are looking for.

Today’s poking and prodding

They tested my ability to remember long lists of different kinds of things, particularly after being distracted in various ways. They tested my spatial reasoning in a number of paper and computer based exercises. One annoying one was trying to pick out four different three-digit sequences from a rapid string of numbers, pressing a button when I saw one of them. Because you mind tends to break up the string into a distinct series of three digit numbers, this is extremely hard. 233453456 becomes 233 453 456 starting at wherever you started thinking about it. As such, it is hard to see that 334, for instance, is part of the sequence.

One unusual bit involved playing a betting game on a computer. It showed two bars per screen, yellow in situations where I could win points and blue in those where I could lose them. Some bars were solid and had a single number on them. If you picked them, you were certain to win or lose that amount. Most were split into two fractions, where one was 1/3 of the bar or smaller. Usually, the choice being made was between the certainty of winning or losing a small amount for sure and the possibility of winning or losing more. For example, you might have to choose between a 2/3 chance of losing a small amount and a 1/3 chance of losing a larger amount or a 9/10 chance of losing nothing and a 1/10 chance to losing an even larger amount.

The curious thing is that, as far as my limited arithmetical abilities under such circumstances could be trusted, the bars were always very close to being or exactly statistically equivalent. For instance, you had the option of a guaranteed 66 points or a 1/3 chance at 200 points. As such, as the game went on, I found myself always choosing the ‘safe’ option. This was because I didn’t know the number of trials. You would expect the numbers to be the same for either strategy over the long term. After one million trials, it wouldn’t matter if you had chosen ’33 for sure’ or ‘1/3 of 100’ in every trial, or used any combination of them. If there were a small number of trials, however, choosing the option with more stable returns is less likely to generate an outlying number of points (high or low).

As the game went on, I thought I was doing no better than breaking even. At the end, it said I had over 10,000 points. Of course, it may just have been saying that. You can never be sure what is actually being tested in such experiments. The last, little thing that tends to happen at the end frequently seems to be the most important bit of the whole sequence. Regardless of whether the figure was meant to toy with my emotions or not, I am pretty sure I will get about another £10 at the end of the experiment for it.

In addition to all that, I was asked to tell little stories in response to words, provide definitions to others, and fill out lots of questionnaires about mood and my (non-existent) gambling habits. When called upon to define the words, I felt a bit like Blackadder when he was trying to re-write Samuel Johnson’s dictionary in one night.

The week ahead

For the next week, I need to wear an accelerometer and light meter, as well as keep a diary of eating, sleeping, and exercise. I am meant to wear the measuring equipment as much as possible, though I am not allowed to get it wet or bare-fist box while it is on my wrist. At the end of the week, they are giving me a functional magnetic resonance imaging scan, a diffusion tensor imaging scan, and testing my cortisone levels.

There are 40 other participants, so the total amount of data generated seems very considerable. I hope they find some interesting stuff in there.

PS. Back in March 2006, I hoped the money from this experiment would help me buy a bike. Funny how slowly some things can proceed…

PPS. One of the pictures associated with the Wikipedia article on DTI scans was used in an Economist article this week about synesthesia.

Tragedy of the commons

As a discipline, International Relations is packed with parables. Sometimes, they are hypothetical stories and sometimes they are interpretations of historical events. In each case, they are meant to demonstrate something important about how world politics works. Almost without exception, some aspect of their validity can be questioned on either historical or logical grounds.

When it comes to global environmental politics, perhaps the most well-known such parable is the ‘tragedy of the commons.’ Garrett Hardin is generally credited with coming up with the idea in a paper published in 1968. That said, the same idea was expressed in Michael Graham’s 1948 book The Fish Gate, in which he described how fisheries where access is unlimited will inevitably become unprofitable and fail. The logic of an individual who cannot control the entirety of a resource grabbing as much as possible before its inevitable destruction is the key feature of both analyses.

Personally, I would rather give the credit for the idea to Graham, rather than to Hardin (though it probably far precedes either of them). After all, the latter thinker went on to write such logically and ethically dubious documents as Lifeboat Ethics: the Case Against Helping the Poor. In an illustrative passage, Hardin says:

A wise and competent government saves out of the production of the good years in anticipation of bad years to come. Joseph taught this policy to Pharaoh in Egypt more than 2,000 years ago. Yet the great majority of the governments in the world today do not follow such a policy. They lack either the wisdom or the competence, or both. Should those nations that do manage to put something aside be forced to come to the rescue each time an emergency occurs among the poor nations?

His assertion that affluent societies are such because their leaders have set aside a surplus in times of plenty, whereas the leaders of poor societies have not, represents a massively myopic and superficial understanding of the processes of wealth accumulation, as well as the interactions between historically dominant and historically oppressed states. Explaining patterns of development in such a simplistic way obscures important elements of world economic history. Going on to justify a cold-hearted ethic of indifference to suffering and injustice outside the rich world likewise represents inappropriate extrapolation and faulty thinking.