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EFFECT OF THE ELECTRIC CAR ON THE
ENVIRONMENT AND ENERGY SUPPLY


Vlado Bevc


Paper presented at the Rutgers University
Advanced Workshop in Regulation and Public Utility Economics
Seventh Annual Western Conference, San Diego, California
July 6-7, 1994

[Views expressed in this article are those of the author]

ABSTRACT

   Estimates are presented which may be relevant in evaluating the
effects of large scale introduction of electric cars on the
environment and the demand for electrical energy.  There are 17
million cars in California.  The mandated program for introducing
electric cars in California would have only an insignificant effect
on the reduction of air pollution. Only when the number of the
electric cars displacing the conventional internal combustion
engine automobiles would approach several million of vehicles would
there be a noticeable effect on the reduction of automobile related
air pollution. At present the electric rates for recharging a few
electric cars at night are low because the demand for the energy at
night is low.  The load represented by charging, for instance, 5
million cars at night would be of the order of magnitude of the
largest electric demand peaks of California's largest utilities
(19,000 MW).  With such demand there would be no low electric rates
available at night.  Use of batteries on a massive scale would
create a demand for lead approaching or exceeding the world
production quantities and would require significant changes in the
production, processing and recycling of this metal which is subject
to the toxic substances regulation.  An evaluation of the related
health and environmental hazards is recommended.  The above
problems may well vitiate the presently held expectations for a
large scale application of electric cars.

    California Goals and Objectives.  The goals set for the number
of the electric cars to be introduced in California have been set
by legislation [1] and the California Air resources Board.[2]  The
regulations of the Air Resources Board require that, beginning in
the year 1998, 2 percent of all new cars sold in California will
have to be zero emission vehicles, 5 percent by 2001, and 10
percent by 2003.  California Department of Motor Vehicles reports
that in 1993 there were 17.10 million automobiles of which 1.67
million were new vehicles.[3]  In the Los Angeles County there were
4.80 million automobiles.  Examination of the vehicle registration
trend shows that this number has remained within one percent of the
totals since the year 1991 and the DMV forecasts predict
essentially no substantial change in these numbers until the year
1996.  It is therefore reasonable to use these numbers in our
estimates bearing in mind that by the end of the year 2003 the
totals will most likely not change by more than 10 percent.  If the
state mandated goals are met there will be 434,000 low emission
vehicles in California by the year 2003. This figure is in
agreement with the expectations quoted by the California Electric
Vehicle Task Force.[4]

  At the very best, if all the low emission vehicles introduced in
compliance with the mandate were electrical cars and if we could
assume that electrical cars cause no air pollution at all, the
total air pollution reduction attributable to the displacement of
gasoline powered cars by the above quantity of electric vehicles
would be no more than 2.5 percent.  The achievement of the mandated
goal would thus not have a significant effect on the air pollution.

The mandated program no doubt carries with it the expectation that
it will somewhere in its evolution trigger a technological
breakthrough that would eventually result in the replacement of the
conventional cars with electrical vehicles.  It is thus of interest
to consider the effect of replacing between 5 and 10 million
gasoline powered cars with electric powered vehicles.  Specifically
we consider the energy requirements on the electric utilities and
the demand for lead used in manufacturing the storage batteries. 
We note that 5 million is approximately the number of automobiles
registered in the Los Angeles County.

  Energy Requirements. The typical requirement on an electric
automobile within the constraints imposed by the size and capacity
of the battery is that it should have a range of some 80 miles and
a top speed of about 60 mph.  One can readily estimate the required
energy that must be supplied to obtain this performance which in
turn provides the requirement for the capacity of the battery used
to power the vehicle.  To move the car over the desired range it is
necessary to overcome the air and rolling resistance which are
about the same order of magnitude.[5]  For a typical American car
weighing 2,000 kg (4,410 lb) the combined resistances amount to
about 100 kg (220 lb) at 60 mph (26.8 meter/second) which
translates to a traction power of 26.8 kW or 35 hp.  This power
sustained over a range of 80 miles at the specified speed requires
an energy of 36 kWh.  The capacity of the battery must be at least
that much.  The above result is compared with the specifications
for two commercially available electric vehicles.

  Consider first the General Motors G-Van.[6]  Although with its
weight of 3,900 kg (8,600 lb) the G-Van is not a personal
automobile, it is useful to compare its battery capacity with the
above estimate.  According to the specifications, the 36 lead acid
batteries constituting the power storage pack have a capacity of
44.28 kWh.[7]  On the other hand, General Motors Impact, weighing
1,000 kg (2,200 lb) is much lighter than the average American car. 
Its specifications give the capacity of a power pack consisting of
32 batteries as 13.6 kWh.[8]  These two battery capacities can be
considered as bracketing values for the energy storage
requirements.

   Charging Power Requirements. It can now be estimated what would
be the power required to recharge 5 million cars every night.  If
we assume a charging time of 8 hours and battery capacities of 40
kWh, which is at the high end of the scale, the electric load would
be 25,000 MW (megawatts).[9]  If the battery capacities were no
greater than 13.6 kWh the corresponding load would be 8,500 MW. 
For the year 1998 the California Energy Commission forecasts [10]
peak demands of 18,000 MW for the Pacific Gas and Electric
Company's territory and 19,000 MW for the Southern California
Edison Company's territory.  An additional load of some 10,000 MW
represented by the recharging of car batteries would thus be of the
order of the peak demands of the two largest California electric
utilities.  A demand of this magnitude, assuming that it can be
readily met, is not likely to allow the present off- peak rates of
about 4.5 cents/kWh to remain in effect because the electric utilities
would experience another peak at night when the recharging would
presumably be carried on.  This would vitiate the present low cost
of night-time electrical energy as fuel which is often quoted as an
advantage of the electric powered cars.

  Battery Weight and Lead Content.  In addition to the energy
supply problem, quite apart from the fact that additional electric
power generation on a scale comparable to the present would
introduce a commensurate amount of air pollution,[11] it is
necessary to examine the requirements for lead used in the
lead-acid batteries.

  The weight of the battery can be estimated from the specific
energy (i.e., energy per unit of battery weight) of the available
batteries.  The specific energy of commercially available batteries
ranges from 20 to 40 Wh/kg.[12]  Taking the highest available
specific energy figure of 40 Wh/kg we see that the required battery
weighs for the above capacities would be 1,000 kg (2,200 lb) and
340 kg (750 lb) respectively.  Lead constitutes approximately 65
percent of the weight of a battery,[13] accordingly, from 220 to
650 kg of lead would be required for each car.  With 5 million cars
this would amount to 1.1 to 3.25 million metric tons of lead.  This
is a sizable order in view of the fact that in the total 1991 world
production of lead was 3.318 million metric tons of which 14
percent or 464,000 metric tons was produced in the United
States.[14]  It would be necessary to evaluate the impact on the
production, processing, and recycling of quantities of lead
approaching the world production figures.  Although the operators
of the lead acid battery recycling processes are able to recycle 95
percent or more of lead, substantial and extensive changes in the
processing of the volumes that have hitherto not been handled would
have to be made.  The implication, however, that introduction of
electric cars on a massive scale would increase the amount of lead,
a toxic substance, several times over its present amount is
inescapable.

  Conservation of difficulty, Entropy?  With the above indicated
issues that might militate against or diminish the expectations we
have for a large scale application of new technology, the question
arises whether by improving or making things better in one area we
are not degrading the situation in another area.  Introduction of
technologies such as the electric car has to be evaluated with
respect to their overall effect on the world we live in so that we
can make the assessment whether the resulting additional disorder,
disruption, or pollution will be something we can perhaps more
easily manage and live with.  For the electric car we have clearly
the view: these vehicles pollute less than the cars presently in
use.  This is true so far as it goes.  But we have seen no studies
that will show the entire picture, namely, what does it take to get
the electric car in place and whether to do so we may increase
pollution or cause environmentally deleterious effects elsewhere
such as increased thermal and chemical pollution outside the Los
Angeles basin from the additional power generation, both fossil and
nuclear, and lead and acid processing by the industry manufacturing
all the required batteries.   

REFERENCES

1.  California Public Utilities Code Section 740.2.

2.  California Code of Regulations, Title 13, Section 1960.1(g)(9)

3.  Estimated Fee-Paid Vehicle registration by County, 1992 Annual
Report, State  of California Department of Motor Vehicles,
Sacramento, February 19, 1993.

4.  A California Plan for the Commercialization of Electric
Vehicles, vol. I, California Electric Vehicle Task Force, November,
1989, p. 7.

5.  See, for instance, Marks' Standard Handbook for Mechanical
Engineers, 7th edition, Theodore Baumeister, Editor, McGraw-Hill
Book Co., 1967, p. 11-4.

6.  Electric Vehicle Highlights, Southern California Edison
Company, Rosemead, California, 1990.

7.  Note also that this vehicle moving at its top speed of 52 mph
would require a traction force of 190 kg (415 lb).

8.  Impact, General Motors Vehicles, 432 North Saginaw Street,
Suite 801, Flint, Michigan 48502.

9.  The G-Van has an off-board charger with a power rating of 7 to
8.75 kW.  Such chargers would produce even larger demands than
estimated in this here if they were all connected at once, however,
it can always be assumed that customers could stagger the charging
of their cars so as not to overload the system.

10. Committee Recommendations for Adoption of Electricity Demand
Forecasts California Energy Resource Conservation and Development
Commission, Docket No. 90-ER-92, February 1992, pp C-25 and C-27.

11. It is assumed that nuclear power will probably remain
unacceptable in California.

12. The manufacturer of the Horizon battery reports that it has
achieved a specific energy of 50 Wh/kg in its product soon to be
placed on the market.  However, the most efficient battery that
can be purchased at present has a specific energy of 40 Wh/kg.

13. Handbook of Batteries and Fuel Cells, D. Linder, editor,
McGraw-Hill, Inc., p. 14-15.

14. U.S. Bureau of Census, Statistical Abstracts of the United
States:1993. 113th edition, Washington, DC, 1993.

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