Getting Up the Energy
Decatur Metro | December 15, 2010
Chart above from page 128 of David JC MacKay’s book “Sustainable Energy: Without the Hot Air”. (Thanks to FJ for the link!)
Aside from the energy usage of all these other modes of transportation, this chart echos my earlier ad-hoc and not-to-be-trusted calculation that an electric car uses about 1/4 or 1/5 the energy of a gas-powered car. It also shows that an electric car with one or two passengers uses more energy than a “full” electric train. Of course, electric trains aren’t always going to be full, so the “per passenger” number is actually a bit higher.
So now that we have a bit better sense of how these modes of transport relate to each other, lets introduce lifestyle back into the equation. Does living in an urban environment, taking the train, biking and walking, use more or less energy than using an electric car on a regular basis? Because while biking and walking will always use minimal energy, a half-full train can ratchet up your daily energy consumption pretty quickly.
Basically, which will use less total energy: a small, walkable town on a mass transit line or a subdivision serviced by electric cars?
The Rebound Effect Or Why A Prius Won’t Save The Planet
http://andrewsullivan.theatlantic.com/the_daily_dish/2010/12/the-rebound-effect-or-why-a-prius-wont-save-the-planet.html
Money quote: Efficiency doesn’t reduce consumption; it increases it.
Not a surprise if true, because efficiency, in the case of a car, reduces the cost of operating it. If it is cheaper to use a good, many people will use more of it.
If we really want cars to use the least amount of energy possible, the price of fuel needs to go up. I don’t think there is any real alternative. A steep rise in the gas tax is one of the only new taxes I support. If the peak oil folks are right, the tax will be temporary anyway.
How about a reduction in the effeciency of fuel? Take ethanol, for example.
So a hovercraft is more efficient than a Range Rover?
My plan to solve Atlanta’s transportation woes by constructing jet-ski canals throughout the Metro area now appears less eco-friendly than I anticipated, alas.
There’s always catamaran!
I’m just really glad that our boat is not a dot on this graph or we might be run out of town.