[SGVLUG] [OT]Hybrids and trains (was fuel prices and the dollar)

[David Lawyer]

I've submitting the following letter to the editor of the LA times.
Not sure they will print it.
			David Lawyer
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Re: "Civilization's last chance", May 11

The implication that hybrid autos and trains (instead of airplanes)
could make much of a difference in global warming is simply wrong.

Hybrids use internal combustion engines no more energy-efficient than
the engines on non-hybrids.  They also waste a lot of energy converting
the gasoline motor power to electricity, charging a battery, and then
withdrawing energy from the battery to power an electric motor to move
the car.  All this energy conversion wastes energy and adds to the
weight of the car.  The reason hybrids get good mileage is not because
they are inherently efficient, but because people don't know how to
efficiently drive a non-hybrid and because laws and car design, etc.,
impede one from efficiently driving it.

To efficiently drive a non-hybrid, one needs to get a "brake specific
fuel consumption map" for their engine, which the auto companies don't
supply.  Then use the map to apply the optimal amount of torque at any
given rpm, but autos have no torque meter.  Efficient driving will
mean doing a lot of coasting but coasting in neutral is illegal.

As for trains vs. airplanes, it turns out that they are about equally
energy efficient, and we don't save energy by taking the train.  See
the U.S. Dept. of Energy's "Transportation Energy Data Book": edition
26, table 2.14, and account for the fact that about 15% of fuel for
passenger aircraft goes to transport freight in the cargo hold.  For
details see my "Fuel-Efficiency of Travel in the 20th Century"
http://www.lafn.org/~dave/trans/energy/fuel-eff-20th-3.html#air_eff