Without the Hot Air

I recently posted about a talk I saw about meeting our global energy needs in the future.  To me, one of the frustrating things about the whole conversation is that there aren’t hard numbers comparing one scenario to another.  For example, I’ve heard that if we cover all of New Mexico in solar cells, we could meet the energy demands of the entire nation.  However, I’ve not heard how much that would cost and how that compares to say building new nuclear power plants.

Clearly, I’m not the only one with this frustration.  And someone has done something about it. David J.C. MacKay, Professor of Natural Philosophy in the Department of Physics at University of Cambridge, is working on a book to answer precisely these questions.  As he says, we need “numbers, not adjectives” in trying to decide how to both meet our energy needs and to reduce our green house emissions.  On his website, Without the Hot Air, he presents a draft of a book in which he compares the possible energy sources available to Great Britain with the energy consumption they are currently using.  I’ll admit I haven’t read his book, yet, but I went through some of his slides and his executive summary, also available on his website.  The upshot:  Britain cannot generate the power it currently uses from renewable sources available only within Britain.  And that is if, for example, all land in GB was used for power generation of one sort or another, which, as he points out in his slides, would make a lot of people unhappy (he shows protests against off-shore wind farms, where the protestors bemoan the destruction of scenary).

And, as opposed to a lot of people who bemoan our current situation (i.e. Al Gore), Dr. MacKay gives concrete plans that embody different policies (such as a Green plan which uses no coal or nuclear to an Economic plan that relies heavily on nuclear) to solve Britain’s energy problem.  These rely upon two things: increasing energy production, which in the case of Britain seems to involve getting power from other countries that can produce more renewable energy, and decreasing energy consumption.  Both are key to a solution to the problem.

One interesting side tidbit I saw in his slides: I guess one reason people don’t like windmills is that they kill birds.  He compares the number of birds killed in Denmark, which has a much higher number of windmills than GB, by windmills and cars and the number killed in GB by cats.  The number killed by cars dwarfs those killed by windmills, and the numbers killed by cats are many orders of magnitude greater than either.  Just an interesting tidbit.

Anyways, without hard analysis like Dr. MacKay’s and the corresponding realistic look at possible solutions, we will never solve the energy problem.  A prime example is biofuels.  Biofuels are touted as a great advance in addressing the problem.  However, everything I’ve read suggests biofuels are, at best, a distraction and will not help in any significant way.  That they are so highly touted by politicians and the like just distracts us from real solutions.

Some other links I found on Dr. MacKay’s site: his blog, where he discusses energy claims in the media and other aspects of energy consumption and Sandy Polak’s site, which discusses ways to reduce your carbon footprint that are realistic.

(The figure is from Dr. MacKay’s website.)

8 thoughts on “Without the Hot Air”

  1. I’m with you on your interest in Dr MacKay’s proposition for ‘numbers not adjectives’ but there is a big problem with the often quoted ‘more birds killed by cats…’ statistic, in that it is a nonsequitar. The problm is not the numbers of birds (and bats) killed by the blades, they are usually migrating raptors… cats are much more likely to be prey for these large birds rather than predator to them. The turbine blades from a modern 3 megawatt turbine are 43.5 meters long, rotating at 19 RPM, for a tip speeds of 312 killometers per hour (193 MPH). The birds and bats have never encountered anything like this in their evolution… and its a one-time encounter when they do!

    As for bats, several of our larger species in the U.S. (that don’t occur in Europe) migrate along ridge lines in the spring and late summer, and are encountering these wind farms, also frequently found on ridges. There is a lot of info availible on this at Bat Conservation Int’l. . There has been very little cooperation from the wind energy industry for studying the bat problem. BTW, the motivation for the sudden wind energy push is that the industry (primarily big energy corporations) are currently getting tax credits against thier ‘other’ energy operations).

    Okay, that my 2 cents worth!

  2. I guess I should have said ‘not the numbers, but the type of birds (the species involved) which are not the numerous soung birds that cats usually enounter.


  3. Greg, those are good points. To be fair, I don’t know if Dr. MacKay goes into that in his book, that the types of birds affected by cats vs windmills are very different. I haven’t read the whole book.

    I agree that there are always hidden agendas, especially by the industries, but I think Dr. MacKay is trying to be as neutral as possible and is just trying to give some perspective on the size of the problem.

    It seems to me that no technology is perfect and that there will always be people opposed to one technology or another. I wonder if, overall, more birds are killed by pollution from fossil fuel burning than windmills, but that is a less direct death. However, unless we dramatically change the way we live, which seems unlikely, we need to implement some of these technologies soon, or things are just going to get a lot worse.

  4. I think you are absolutely right, Greg. The concern here is for raptors, bats, albatross, etc. And there are serious environmental consequences when we tamper with the food chain, be it intentional or not.

    I wonder if work can be done on the design and/or placement of wind mills to minimize the mortality and migratory impacts to the birds and bats. Perhaps wind mills should be thought of dams, and “bird ladders” need to be put in place. This is an opportunity to thoughtfully design and place wind mills from the onset, rather than throwing them up in an energy panic and then realizing we have made an even bigger mess.

  5. Hi Luistxo. Well, I am pro-nuclear. Most of the research the team I am on does is materials for various aspects of nuclear energy (work that won’t make much a difference now but hopefully lays the foundation for improvements in the next generation). I personally think that the only way we will be able to meet the demands for energy that the world will increasingly make is to have nuclear energy. There seems to be absolutely no way we can generate enough energy via renewables, especially as the rest of the world moves closer to US consumption (which, it seems, they will as they become wealthier, as there is a direct correlation between wealth and energy use).

    Also, I think that, while nuclear has its problems, and the waste is particularly nasty, at least it is self-contained. It is in a well-defined place. The waste from coal is just spewed into the air so no one sees it, but it is a lot more and harder to contain. To power a 1 Gigawatt power plan, you have to burn 8000 tons of coal or 3 pounds of uranium. That, there, is the real reason I’m pro-nuclear.

  6. Thanks for the explanation. I’ve read about some of your works with Germanium. You know, of course, that I understand it perfectly, but for the wandering netsurfer that might arrive here by chance, would you elaborate how your work relates to the next generation of nuclear?

  7. Well, we are studying the fundamental response of materials to radiation, to determine what materials survive radiation and which ones fall apart and why. The goal is to identify new materials and predict maybe new materials that would make for better reactors 30 years from now, improvements that would lead to better efficiency and performance. Not sure if that is what you were looking for…

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