electric car page

For
Example

A
practical motor vehicle needs about 30 KWH
of deliverable energy for

a
range of 100 miles.

For
reasonable performance about 20 hp must be
delivered to the drive train.

Efficiency
of energy delivery from batteries to drive
train is about 40%

Delivered
energy = 40% of stored energy

So
you need 30 KWH/0.4 = 75 KWH of stored
energy

Energy
storage density of lead-acid batteries is
.04 KWH per kilograms

So
you need 75/.04 = 1875 = 4125 pounds of
lead-acid batteries

Power:
20 hp/0.4 = 37.3 KW

Power
density of lead-acid batteries is .07 W/kg

So
you need 37.3/.07 = 533 = 1172 pounds

So
the range requirements are more severe
than the power requirements.

Improvements
in battery Technology are definitely
required.

 

Other
types of batteries:

Material
Energy Density (W-hrs/kg) Power Density
(W/kg) Comments

Lead
Acid 40 70 Long Cycle Life

Nickel
Iron 55 100 Very Long Cycle Life

Sodium
Sulfur 90 100 300-350 C operating temp

Lithium-Iron
sulfide 100 > 100 400-450 C

Nickel-Zinc
75 120 low cycle life

 

Driving
Habits and Requirements:

Long
distances – Interstate –> 75 mph and
400 miles range

Daily
Commute –> 55 mph and 35 miles range

Puttering
around town –> 35 mph and 20 miles
range

It
is very unlikely that electric cars will
ever have production line performance that
satisfies the Interstate requirement.

Most
practical application is for in town
commuting/shopping and this would then
eliminate a major source of air pollution

The
Key of course is marketing –> people
have to buy the product

Performance
–> people need to change their driving
habits

Range
–> not a problem for in town use. City
ordinance to make city limits and internal
combustion free zone would clearly help

Price
–> Probably needs to come down to 10K
before people would seriously consider
this “glorified golf cart”

Safety
–> Lightweight materials –> carbon
fiber. High tensile strength but not a
Farady Cage (thunderstorm problem!). Also
braking is a concern.

 

California
Mandate:

1998:
2% of all vehicles offered for sale must
be zero emission vehicles (meaning
electric cars)

2003:
10% must be zero emission

As
of Fall 1995 the Mandate has been rolled
back (see also this release

 

Some
Prototypes:

 

Ford
Ecostar two-passenger electric mini-van
used by Post-Office and UPS –>
sodium-sulfur batteries

Chrysler
TEVan –> nickel-iron batteries

$500,000
given to Yosemite to replace diesel buses
with electric buses

$500,000
given to General Motors to loan 50
vehicles to 1000 people nationwide for
test drive results

(Most
of the above Information from The
Electronic Universe Project)

http://zebu.uoregon.edu/1996/ph162/l8.html

 

 

 

Electric
Cars, The Future Is Here

 

What’s
Wrong With My Car?

The problems
of greenhouse warming, air pollution and oil
security are all linked to fossil fuel
combustion. Transportation contributes 30% of
the carbon monoxide emissions in the United
States as well as two-thirds of the USs oil
consumption.

SUVs,
the Real Truth

You‘d think by
the number of SUV vehicles in Western nations
that their road system was horrible and the
terrain was that of the rockie mountains.
Yet, western nations have better road system
than any other nation in the world, with more
money spent on good highway system than
education. The Auto-industry advertising
portrays SUVs as the ticket to freedom and
the great outdoors. Commercials depict them
climbing massive snowcapped mountains or
tearing through desert sand dunes, taking
their owners into the wild. Missing from
these ads are other contributions from
SUVs—the brown haze of air pollution
hanging

over many of our
national parks, images of weather disasters
linked to global warming or the
oil

derricks and tankers
needed to feed gas-guzzling SUVs. And in
reality, the only off-road action many of
these vehicles see is accidentally driving
through a flower bed next to the
driveway.

The real truth about
SUV’s when it comes to wasting energy,
they are out rivaled. Built with outdated,
gas-guzzling technology, many SUVs get just
13 miles per gallon. And the higher gas
prices are, the more money they waste.

The reality is that
SUV’s contribute 43 percent more
global-warming pollution and 47

percent more air
pollution than an average car. SUVs are four
times more likely than cars to
roll

over in an accident
and three times more likely to kill the
occupants in a rollover. They also
cost

the owner thousands
more on gasoline.

 

 

 

What
can we do?

As vehicle
use continue to increase, the U.S. as well as
other countries have to address these issues
or else confront the environmental, health,
economic, and political related consequences.
The large industries and policy makers thus
have four options: 1.) To reduce vehicle use,
2.) To increase the efficiency and reduce the
emissions of conventional gasoline-powered
vehicles 3.) To switch to less noxious fuels
or 4.) To find less polluting propulsion
systems. Although each option is attractive,
in reality people, especially in more
developed nations, are not going to reduce
using their cars; if they have a car, they
will use it. In addition, although
alternative fuel use is an equally appealing
and potential low cost option, these
alternative fuels, such as methanol or
natural gas, burned in internal-combustion
engines, would only lead to marginal
reductions in pollution and greenhouse gases.
The final option, of finding a less polluting
system, such as the electric car option, all
together would be an actual solution to some
of the above problems because using electric
motors could reduce overall urban pollution
and greenhouse emissions 20% less than a
regular mechanical gas online-powered
vehicle. Therefore, laying a foundation
system for a transportation system that could
ultimately be pollution free would be the
most effective step in solving some of the
already detrimental hazardous that come from
the combustion of fossil fuels through car
use.

 

 

 

 

 

 

 

 

 

 

 

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What
is an electric car?

The term
“electric-drive vehicle” includes
not only those cars powered by batteries
charges with household current, but also
vehicles that generate electricity on board
or store it in devices other than batteries.
Electric vehicles are sometimes referred to
as “zero-emission vehicles” because they
produce essentially no pollution from the
tailpipe or through fuel evaporation. This is
important, for it means that the use of
electric vehicles could greatly reduce
emissions of carbon monoxide and smog-forming
pollutants in cities with dirty air. Electric
cars are different than gas powered cars
because they have an efficient electric motor
that drives the wheels and extracts energy
from the car’s motion when it slows
down. In contrast, internal-combustion cars
have a constant running engine whose power is
driven through a series of gears and clutches
to drive the wheels and to turn the
generator. Additionally, electric cars are
more efficient because the electric motor is
connected to the wheels, thus it consumes no
energy while the car is at rest or coasting,
which increases the potential energy by
roughly one-fifth. Regenerative braking
schemes can return as much as half an
electric vehicle’s kinetic energy to the
storage cells. Also, the motor converts more
than 90 percent of the energy in its storage
cells to motive force, contrasting the
internal combustion drives which utilize less
than 25% of the energy in a liter of
gasoline.

 

 

Hybrid
Cars:

Hybrid electric
vehicles have batteries to provide electric
power but are also equipped with a small
internal combustion engine (usually powered
by gasoline). Thus like electric cars,
hybrids use a combination of energy sources
including a battery, yet unlike the electric
car, the hybrids’ batteries never have
to be recharged. The hybrid vehicles will
reduce emissions almost as much as battery
powered cars especially in regions where most
electricity os generated with coal.

The engine provides a
power boost and/or can be used to recharge
the batteries, as pure electrics today simply
cannot achieve the range, performance, or
convenience

of a modern gasoline
car. Unfortunately, the extra engine
substantially increases pollution from the
vehicle, erasing many of the air quality
benefits of pure electric vehicles.

Fuel
Cells:

Fuel cells
burn hydrogen to produce water vapor and
carbon dioxide, emitting no other emmitants
as they generate electricity. Fuel cells are
the least polluting of any method for
producing motive power for cars.. Using fuels
such as natural gas, methanol, or petroleum,
the fuel cells produce hydrogen, which is
electrochemically combined with oxygen from
the air to produce electricity. Heat and pure
water vapor are the only byproducts from the
fuel cells’ electrochemical reaction.
Phosphoric acid- based fuel cells are
currently the most attractive for car use,
yet the cost is still an issue. The ideal
fuel for fuel cells is hydrogen Hydrogen can
be made from many different sources, but when
fossil fuels become scarce and expensive,
hydrogen will most likely be made from water
using solar cells. If solar hydrogen were
widely used, the entire energy transport
system would be enviro-friendly and fully
renewable.

The
Future:

 

“At Toyota,
we firmly believe that there is more than one
answer to the issue of personal transport
systems for the 21st century,” said Watanabe.
“Toyota is committed to making a true impact
on a global scale to eco-projects, and to
contributing to the sustainability of the
automotive world.”

-President
of Toyota

Alternative
approaches to gasoline powered cars have
captured a world-wide attention among
industry, environmentalists, and consumers as
an option for improving air quality and
lessening dependence on imported oil.
California currently leads the nation in
promoting cleaner vehicles and there is
intent to force technological development in
the widespread commercial introduction of
electric vehicles. The U.S. department of
energy has awarded $13 million in research
grants to companies willing to explore
alternative power sources. The new fuel
cells, for example will be designed to emit
almost no pollutants and should not exceed
even a dollar for the equivalent of a liter
of gasoline.

In addition
to power sources, advances in aspects of
electric vehicle technology has increased in
recent years. A technological revolution in
electricity storage and conversion devices,
electronic controls, software and materials
is beginning to generate new opportunities.

 

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