2003 Note to Some Friends About Electric Cars

From: Danny Sleator sleator@cs.cmu.edu
To: Michael DeKay dekay@andrew.cmu.edu
cc: guyb+@cs.cmu.edu, nmd@cmu.edu, tomek+@andrew.cmu.edu,
Illah Nourbakhsh illah@ri.cmu.edu
Subject: electric vehicle (EV) versus conventional vehicle emissions
Date: Sun, 24 Aug 2003 18:07:13 -0400

Here are three sources on this question. Regarding
greenhouse gases, I found this DOE study. It shows that EVs
reduce greenhouse gas production by between 25% and 70%,
depending on the type of generation used.

(page 37)

I also found an overall analysis by Engineer Phil Karn, who
used to have an EV (until it was recalled).

(also see http://www.ka9q.net/ev/)

According to his analysis of power generation in California,
and the efficiency of his own car, emissions in all
categories he analyzed (he didn't do CO2) are reduced by at
least a factor of 10.

Consistent with this I found:
On which it says:

In another study of six driving cycles in four
U.S. cities, BEVs [Battery EVs] reduced HC and CO
emissions by approximately 97%, regardless of the
regional source fuels mix. In comparison to large
generating plants, conventional cars produce large
amounts of HC and CO emissions, mainly because of cold
starts and short trips that do not allow vehicles to
become fully warmed up.

You also mentioned the issue of the pollution involved in the
manufacture of the lead-acid batteries. I think modern EVs
use nickel-metal-hydride batteries. I know nothing about
the pollution involved in production and recycling of these
batteries. I do know they last a very long time (100,000
miles and beyond). Of course, as manufacturing volume
increases, serious pollution problems could presumably be
addressed in a way that they're not addressed now. You also
have to consider the savings obtained by the fact that you
don't have to manufacture a lot of other stuff, such as

So I'm still very skeptical of what you said today. I'd be
interested in seeing the report you mentioned.

Left Out Home
Danny Sleator
Last modified: Wed Aug 23 15:31:03 2006