“Be kind, for everyone you meet is fighting a hard battle” - Often attributed to Plato but likely from Ian McLaren (pseudonym of Reverend John Watson)

Sunday, October 25, 2009

Olduvai?

There's a cheery website called "Dieoff" that does a pretty good job of factually presenting the worst case interpretation of demographic, economic, and resource consumption data. A contributor to the site, Richard C. Duncan, Ph.D., is the nominal (he acknowledges the contributions of many others) originator of the so-called "Olduvai Theory" which posits that we're quickly headed for a "post-industrial stone age."



The metric used by Duncan is per capita energy use. It seems to be a reasonable idea - mankind's ability to convert energy at ever-increasing rates has gone hand in hand with increasing standards of living (at least in those societies able to capitalize on it). And ranking of countries by primary energy use looks pretty similar to a ranking by standard of living, though there are exceptions at the high end.



Duncan cites a variety of sources indicating that per capita energy use peaked somewhere in the 1973-1979 time period. It's estimated that peak per capita energy use was about 11.15 boe (barrels of oil equivalent) or 6.46*10^7 BTU. He predicted that per capita energy use would decline at a rate of about 0.33%/year after that. Such a decline would lead to a 2008 per capita use of 10.47 boe or 6.07*10^7 BTU. What's happened?



Using BP's incredible site, the historical data spreadsheet gives me the data I need (by the way, anyone interested in energy, oil, etc. should spend a lot of time on that site). In 2008, per capita consumption was about 6.68*10^7 BTU. This is actually down from a peak of 7.24*10^7 BTU. The drops in 2007 and 2008 were quite steep.



Since the U.S. uses about 25% of primary energy and about five times the average, our effect on such statistics is huge, and we entered a deep recession in 2007. It remains to be seen what trajectory our recovery, if it comes, will take. For this reason, I don't think the current data support the Olduvai theory, at least at the present time.



It's also opined that the developing nations' striving for increased standards of living will overwhelm the developed world's (and particularly the U.S.'s) efforts at efficiency and I think that this is where the constraint will manifest. Since we use about 32.7*10^7 BTU per capita per year, a little less than five times the average, it's not likely we can find a way to bring the rest of the world to our level of use. And this takes no account of any peak oil consideration.



I've included a graph showing world population, total energy use, and world per capita annual energy use from 1980 through 2008. Click on it to see a larger and clearer version. Note the precipitous drop in the latter two categories in 2007 and 2008.



Friday, October 23, 2009

Modeling

Many of the comments I've seen "debunking" the science behind climate change are based on criticism of "computer models." Such people need to stay off of bridges and out of buildings, cars, ships, and airplanes. All are now designed using computer models. So, just what is a computer model, what can one do, when is one useful, and how can one go wrong?



Let's start with "what is a model?" When a net force acts on an object, that object accelerates. We learn in high school (and I've used repeatedly in this blog) that "F=ma." This constitutes, in a broad sense, a model. After all, the universe is not a calculator and F=ma is a synthesis of the way people (starting before Newton) believe material objects behave. It's been found to be useful and successful but may need to be modified, for example, in situations where the general theory of relativity is applicable.



As it happens, simulations using this model can be run on pencil and paper, with slide rules, or with a calculator. Nevertheless, the equation takes our best understanding of the essentials of a physical principle and, given specific input, will provide predictions of the output. But here's the point: science is about modeling. The world is too complex to track and measure every degree of freedom.



The spreadsheet I used to analyze acceleration is also a model. Again, it involves assumptions, separation of what I believed to be essential vs. non-essential parameters, measurements, and estimates. Like all models, it's subject to error if I've made a mistake in any of these components.



How do I check? In such a simple model, it's fairly straightforward. Does it make sense? How do the orders of magnitude compare? Does it provide reasonable numbers in limiting cases? Does it make predictions that match measured results? In my case, I believe the answers to this question is "yes, to within the accuracy that I can measure."



So what about computer modeling of climate? The models are built by doing what I did for the acceleration of my car, i.e., culling non-essential (or non-measurable) parameters, applying basic physical principles (Newton's Laws, conservation laws, thermodynamic laws, transport and transfer laws, etc.) to initial conditions, and evaluating the output. Like my model, it's an iterative process - the model is tested with input conditions for which output conditions are known and a determination if adjustments are required is made.



Of course, the more assumptions included and the larger the input data set, the more complex (and potentially though not necessarily the more accurate) is the model. The so-called "global circulation models" (GCM's) are quite complex. But as with any model, confidence in their accuracy is gained by comparison with known initial and final conditions. Here is a summary of successes of the GCM's.



The point here is that naive criticism of the process of modeling is completely misguided. Such critics use the results of successful "computer modeling" every day. If one wishes to criticize the models, it must be based on the factors above: wrong choice of parameters; inaccurate measurement of initial conditions, etc. "How can we believe a computer model?" is a question indicative of blissful ignorance. As stated (and demonstrated) in the post cited above, there are improvements to be made, but the current state of the art appears to be very good. And when it comes to physics, models are all we have.

Saturday, October 17, 2009

Is there a psychologist in the house?

Just kidding, my regard for the so-called "soft sciences" is pretty low, though my father was a psychologist. But I'm trying to understand a guy like Marc Morano. Amazingly, Mr. Morano has no Wikipedia entry, so I'm tempted to think he doesn't actually exist. But he's the driving force behind the Climate Depot web site, an aggregator of anthropogenic global warming ("AGW") denial (or skeptic, take your pick) stories modeled very much after the Drudge Report.



Morano was an early promulgator of the Swift Boat Veterans' attacks on John Kerry and has worked for Rush Limbaugh. I've watched Morano in several debates and he's a quick witted and intelligent man and he very clearly has his facts in hand. So what does this man believe? I know what he contends but what does he believe?



I see several possibilities: he's a true believer that AGW is false but thinks those who claim it to be true genuinely believe that it is; he believes it's false and that the professed believers know it's false and are using it as a trojan horse for control of the world's economy; he believes AGW is true but thinks those who pay him really think it's false and he wants to continue to get paid; he believes AGW is true and that his income comes from people who also know it's true but whose economic interests are more important or who think that the consequences of action against AGW are worse than the consequences of warming; and several more possibilities.



Suppose he really is a true believer. I came to the issue leaning toward acceptance of AGW and severe negative consequences but had doubts. Among other sites, my friend Michael Tobis' Only In It For The Gold web site and links and papers therefrom have led me to be fairly firmly in the "it's warming, it's us, it's bad" camp though reading the guys below and the comments on their blogs occasionally still causes doubt to creep in - this is just not my area of specialist expertise. Though I've taken a lot of physics courses I'm no physicist, and though my college major was math and I'm working on an M.S. in Applied Mathematics, I'm no mathematician. I doubt I'm smarter than Morano and I certainly don't have the time he does to devote to the issue. So how can it be that he's a true believer? Is it truly a matter of his being slavishly beholden to his philosophy?



I want to understand Morano, Anthony Watts of Watts Up with That?, Steve McIntyre of Climate Audit and others. I'm not sure it would help in the battle for the hearts and minds of the public and the politicians, but it certainly couldn't hurt to know what's really going on in the minds of these highly popular and influential bloggers.

And I thought my disdain for Bill Maher couldn't get any deeper

My comments about Maher tend to be so vituperative that they don't pass moderation even on blogs whose viewpoints I generally support and when Maher is espousing an opinion with which I agree (admittedly rare), e.g., my first comment at ClimateSight.

But here we find him telling pregnant women not to get the H1N1 ("swine flu") vaccine. And he not only repeats lame pseudoscientific claptrap ("Western Medicine misses a lot") but makes inane factual misstatements (i.e., "lies"). For example, he states that the injected vaccine is a live virus. It is not. If one pregnant woman sees his screed and consequently avoids the vaccine, contracts the disease, and dies, as far as I'm concerned it is depraved indifference tantamount to negligent homicide.

Monday, October 12, 2009

More on efficiency

The spreadsheet I created for my recent post on acceleration has enough data to enable me to make another estimate of the overall efficiency of my transportation system (the Land Rover LR3 HSE) during the acceleration phase. This is because I have a tenth of a second by tenth of a second tabulation of energy used to accelerate and to overcome external forces as well as a tabulation of the fuel used.



Summing the fuel and knowing the heat energy available in the amount burned and summing the energy expended to do useful work and dividing yields the answer: 21.0% using the 45 seconds to 55 m.p.h. regime and 22.7% using the 10 seconds regime. This is actually a little better than I would have imagined. I typically calculate cruise figures estimating 25%, but I'd have thought that accelerating from a dead stop would have a larger negative impact on efficiency. Admittedly, it's a long chain from the data I actually have obtained to the figures I've calculated and the weakest link is my use of a composite engine map adjusted with only a very few points from my specific car but as I've said repeatedly, I love it when multiple lines of data and/or reasoning converge.



If my car required half as much energy through weight and drag reductions and was twice as efficient, I'd use one fourth my current fuel. If we all did.....

Thursday, October 08, 2009

Can we "go electric"?

I'm sure it's been covered elsewhere on the web, but since James Kunstler has declared that we won't be able to keep the transportation system he refers to as "happy motoring," I thought I'd point my brand of quick and dirty calculating at the situation.



I'll start at the Energy Information Administration page here. This site is a gold mine of information for sources and sinks of energy of all kinds, for not only the United States but for the world. We find that in 2008, 8,989,000 barrels of "finished motor gasoline" was supplied in the U.S. per day on average. This represents 4.72*10^16 joules of heat energy of which I'll assume that 22%, or 1.04*10^16 joules are translated to force applied to the earth by tires to do the work of moving a vehicle down the road.



Using estimates from this post of 85% efficiency of chargers and 60% efficiency of transmission, 50% of the energy developed at a power plant winds up in a battery. Electric motors are pretty efficient, Tesla claims 86%. I'm going to go with 85%.



Since this is very rough, I'm going to assume that the vehicles replacing the gasoline vehicles are equally efficient, thus enabling me to merely look at joules at the wheel. Therefore, I need 1.04*10^16/(0.6*0.85) or 2.04*10^16 joules/day. This is energy divided by time, or power and using google's calculator, it equates to 2.36*10^11 watts or 236,000 megawatts.



The current generating capacity of the U.S., according to the EIA, is about 1.05 million megawatts (a little over a terawatt). This is just a little bit below the so-called "generator nameplate capacity" of the generating facilities. In 2007, we used electrical energy at a rate equivalent to about 464,000 megawatts, so adding a need for another 236,000 megawatts (increasing utilization by over 50%) would seem to be problematic. The difference between the actual rate of use and total capacity represents down time for maintenance, peak capacity, etc. and thus is not simply idle generating capacity looking for a use.



To maintain the same ratio of actual usage rate to capacity we'd need to add over 500,000 megawatts of generating capacity. That's a whale of a lot of solar panels and windmills. Or, since an average nuclear generating facility has a nameplate capacity of about 1,000 megawatts, we'll need about 500 of those. Best we had get started.



And of course, this says nothing about the transmission of all this electrical energy via a grid that is currently limping along at best, nor does it address the resources required to set up the infrastructure for such an increase in capacity. While I certainly have my gripes with Kunstler, it's true that simply switching to electric cars is no magic bullet for our peak oil predicament.



Update: an ultra-quick "back of the envelope" calculation indicates that we'd have to cover about 7.4% of the state of Arizona with solar panels to supply this extra electrical energy. Of course, storage might be an issue and I'm not so sure that condemnation of the southern eighth of the state (the extra area needed for storage, switching, support, etc.) via eminent domain would be well received.