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Re: (ET) hybrid ET
On 6 Dec 2003 at 12:24, Gordon Trump wrote:
> Part of the downside of ElecTrak is moving the
> pollution back to the (coal burning?) power plant and it's 35% efficiency
> while we benefit from cleanliness in our yards.
This is an old myth used to dismiss EVs as impractical. Here's an analysis
which debunks it:
http://www.evadc.org/pwrplnt.pdf
In case you can't read the pdf format of the above, I've inserted a plain
text
version below (sorry about the tables). View with a monospaced font for a
slight chance at reading the tables.
Even if you disagree with the analysis below, remember that the situation
for
the ET versus a gas or diesel tractor is dramatically different from the
one
cited here. In this study Chip is comparing road EVs with road ICEs, with
(mostly) efficient emissions control hardware reducing their emissions by
percentages in the 90s (at least when they are new and when the drivers
aren't
flooring the pedal).
But the ICEs used in garden tractors have primitive emission control
systems
at best. They produce far, far more emissions than automobiles. There is
NO
WAY that a powerplant generating the electricity for our ETs puts out
anywhere
NEAR the amount of garbage that a gas or diesel garden tractor spews into
the
air.
What's more, if you charge at night, you're using idle powerplant
capacity, at
a time when their systems are running below peak efficiency. You could
argue
in fact that charging your ET at night actually ^improves^ your local power
plant's efficiency. This makes its emissions reduction even ^more^
significant.
There are places where a gas or diesel tractor may meet individual needs
better than an ET. Each user has to make an informed decision about what
to
use when. But don't rationalize using gas or diesel tractors by thinking
that
ETs just move the pollution to the power plant. It isn't so. Fueled
tractors
are MUCH more harmful to the air than your ET.
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Debunking the Myth of EVs and Smokestacks
by Chip Gribben
Electric Vehicle Association of Greater Washington, D.C. (EVA/DC)
Introduction
As ozone levels in the U.S. remain at unhealthy levels, researchers and
government officials continue to study alternatives to reduce air pollution
from gasoline-powered cars. Among the alternatives are ultra-low emission
vehicles (ULEVs) and zero-emission vehicles (ZEVs). ULEVs are equipped with
emission controls that release only 45 pounds of carbon monoxide per 12,000
miles.1 ZEVs produce no tailpipe emissions at all. ZEVs include vehicles
powered by electricity, flywheels, hydrogen fuel cells, and other
zeroemission
energy sources. Although some ZEVs are still in the experimental stage,
electric vehicles (EVs) are available today. In fact, more EVs roamed the
nation?s roads in the early 1900?s than gas-powered cars did.
Unlike a gasoline car that is powered by an internal combustion engine
(ICE),
an EV uses electricity stored in batteries to power one or more electric
motors. When the batteries need recharging you simply ?plug-in? from the
convenience of your home. EVs have no tailpipe or evaporative emissions2
because they have no fuel, combustion, or exhaust systems. In fact, EVs are
virtually maintenance free because they never need oil changes, air
filters,
tune-ups, mufflers, timing belts, or emission tests.
One of the most common issues surrounding EVs today is their status as
ZEVs.
Critics proclaim that EVs are simply ?elsewhere emission vehicles? because
they transfer emissions from the tailpipe to the smokestack. Although there
are emissions associated with coal and oil-fired power plants, smokestack
emissions associated with charging EVs are extremely low.3 In fact, EVs can
charge from zero-emission sources such as nuclear, hydroelectric, solar,
and
wind power.
The purpose of this paper is to prove that EVs recharging from today?s
power
plants are substantially cleaner than even the most efficient ICE vehicles.
The myth that EVs are ?elsewhere emission vehicles? will be put to the test
with facts that clearly show EVs and power plants are cleaner, more
efficient
and more reliable then the infrastructure that supports ICE vehicles.
The Effects of the ICE Age
The golden age of the automobile has lasted more than 50 years, however,
the
golden haze caused by our love affair with the ICE car will have long
lasting
effects. Despite stringent standards to improve tailpipe emissions, the
number
of vehicles and miles traveled are increasing every year. Scientists
predict
that our increased reliance on the automobile could increase pollution
levels
40 percent by the year 2010.4 In California, where the automobile is
considered a necessity, ICE vehicles account for 90 percent of the carbon
monoxide, 77 percent of nitrous oxides, and 55 percent of reactive organic
gases.5 In addition, greenhouse gases such as carbon dioxide, are expected
to
increase approximately 33 percent by the year 2010.6 Continual exposure to
these pollutants can cause a variety of symptoms and aggravate existing
medical conditions. The elderly and the young are more susceptible to the
risks imposed by air pollution. Children in the Los Angeles area have 10
to 15
percent less lung capacity than children in cleaner cities such as Houston,
Texas. The following list describes the potential health risks associated
with
these emissions.
Carbon Monoxide (CO): an odorless and colorless gas which is highly
poisonous.
CO can reduce the blood?s ability to carry oxygen and can aggravate lung
and
heart disease. Exposure to high concentrations can cause headaches, fatigue
and dizziness.
Sulfur Oxides (SOx) and Sulfur Dioxide (SO2): When combined with water
vapor
in the air, SO2 is the main contributor of acid rain. Gasoline typically
contains .03 percent sulfur.7 Nitrogen Oxides (NOx) and Nitrogen Dioxide
(Fuel
Refining)
(NO2): These chemicals are the yellowish-brown haze seen over dirty cities.
When combined with oxygen from the atmosphere, NO becomes NO2, a poisonous
gas
that can damage lung tissue.
Hydrocarbons (HC): This is a group of pollutants containing Hydrogen and
Carbon. Hydrocarbons can react to form Ozone. Some (HCs) are carcinogenic
and
others can irritate mucous membranes. Hydrocarbons include:
? Volatile organic compounds (VOC)
? Volatile organic gases (VOG)
? Reactive organic gases (ROG)
? Reactive organic compounds (ROC)
? Non-methane hydrocarbons (NMHC)
? Non-methane organic gases (NMOG)
Ozone (O3): This is the white haze or smog seen over many cities. Ozone is
formed in the lower atmosphere when NMOG and NOx react with heat and
sunlight.
Ozone can irritate the respiratory system, decrease lung function and
aggravate chronic lung disease such as asthma.
Ozone gases have contributed to smog levels as high as 80 parts per
billion an
average of 84.3 days per year since 1982 in Baltimore, Maryland. Federal
safety standards state the risk level is 120 parts per billion when
exposed to
smog for an hour. However, recent studies suggest that exposure to 80 parts
per billion is enough to cause lung inflammation which can lead to
permanent
scarring.8 Carbon Dioxide (CO2): CO2 is a naturally occurring gas in the
atmosphere and is a necessary ingredient of the ecosystem. However, in
large
quantities it can allow more light to enter the atmosphere than can escape.
The excess heat from the trapped light can lead to the ?greenhouse effect?
and
global warming.
Clearing the Air About Power Plant Emissions
EVs have the unique advantage of using electricity generated from a
variety of
fuels and renewable resources. The overall mix of power plants in the U.S.
is
55 percent coal, 9 percent natural gas, and 4 percent oil.9 The other 32
percent include nuclear power and renewable energy sources such as
hydroelectric, solar, wind, and geothermal.
Many EV critics point out that charging thousands of EVs from aging coal
plants will increase greenhouse gases such as CO2 significantly. Although
half
the country uses coalfired plants, EVs recharging from these facilities are
predicted to produce less CO2 than ICE vehicles. According to the World
Resources Institute, EVs recharging from coal-fired plants will reduce CO2
emissions in this country from 17 to 22 percent.10 Reductions in pollutants
such as HCs, CO, NOx, SO2, and particulates vary according to a region?s
power
plant mix. If EVs were introduced on a global scale urban pollution would
improve significantly. See Table 1. In France, where most of the power
comes
from nuclear energy, emissions produced to charge EVs would be cut across
the
board.
Countries such as the U.S. and the U.K. use a mix of coal and oil-fired
facilities that produce an elevated level of SO2 and particulates. However,
levels of HC, CO and NOx would decrease significantly.
Table 1. Electric Vehicles Reduce Pollution11
(percentage change in emissions)
Region HCs CO NOx SO2 Particulates
France -99 -99 -91 -58 -59
Germany -98 -99 -66 +96 -96
Japan -99 -99 -66 -40 +10
United Kingdom -98 -99 -34 +407 +165
United States -96 -99 -67 +203 +122
California -96 -97 -75 -24 +15
Although half the electricity generated in the U.S. comes from coal-fired
plants, larger regions of the country such as California and the Northeast
are
turning toward cleaner fuels such as natural gas.
In California, where over half of the state?s pollution comes from ICE
vehicles, the overall mix of power plants is one of the cleanest in the
country. See Table 2. Power plants burning cleaner fuels, such as natural
gas,
account for a major share of the state?s electricity. In fact, natural gas
facilities in California emit 40 times less NOx than existing coal plants
in
the Northeast.12 Renewable sources such as hydro, solar, wind, and
geothermal
produce a respectable share of the electricity generated in California.
Table 2. Power Plant Mix in California13
Power Plant Percent
Natural Gas 33
Hydroelectric 20
Coal 16
Nuclear 15
Solar and Wind 6
Geothermal 6
Taking advantage of California?s abundance of sunlight, several utilities
are
using Solar Charge Ports to charge EVs. Charge Ports are facilities that
have
an array of solar panels placed strategically on the roof of the structure.
The solar panels convert sunlight into electricity where it is distributed
to
the vehicles or the adjacent building?s power supply.
On cloudy days the building supplies the electricity to charge the EVs.
Charge
Ports are in operation in several cities in California including Diamond
Bar,
Azusa, and Santa Monica.
Because California has a mix of cleaner fuels and renewable sources,
several
studies have concluded that improvements in air quality can be achieved
easily
by ?plugging-in? to EVs.
The California Air Resources Board (CARB) estimates that EV?s operating in
the
Los Angeles Basin would produce 98 percent fewer hydrocarbons, 89 percent
fewer oxides of nitrogen, and 99 percent less carbon monoxide than ICE
vehicles. In a study conducted by the Los Angeles Department of Water and
Power, EVs are significantly cleaner over the course of 100,000 miles than
ICE
cars. The electricity generation process produces less then 100 pounds of
pollutants for EVs compared to 3000 pounds for ICE vehicles. See Table 3.
Table 3. Pounds of Emissions Produced per 100,000 Miles14
Engine Type CO ROG NOx Total
Gasoline 2574 262 172 3008 lbs
Diesel 216 73 246 835 lbs
Electric 9 5 61 75 lbs
CO2 emissions are also significantly lower. Over the course of 100,000
miles,
CO2 emissions from EVs are projected to be 10 tons versus 35 tons for ICE
vehicles.15
Many EV critics remain skeptical of such findings because California?s mix
of
power plants is relatively clean compared to that in the rest of the
country.
However, in Arizona where 67 percent of power plants are coal-fired, a
study
concluded that EVs would reduce greenhouse gases such as CO2 by 71
percent.16
Similar comparisons to those in California and Arizona can be found in the
Northeastern part of the country where the majority of power plants are
coal-
fired.
A study conducted by the Union of Concerned Scientists found that EVs in
the
Northeast would reduce CO emissions by 99.8 percent, volatile organic
compounds (VOC) by 90 percent, NOx by 80 percent, and CO2 by as much as 60
percent.17 According to a Northeast States for Coordinated Air Use
Management
(NESCAUM) study, EVs result in significant reductions of carbon monoxide,
greenhouse gases, and ground level ozone in the region with magnitudes
cleaner
than even the cleanest ULEV. In the future, EVs in the Northeast will reap
the
benefits of switching to cleaner fuels such as natural gas. In the next 15
years, aging coal plants will be replaced by modern natural-gas fired
plants.
This improvement alone will reduce power plant emissions significantly.
Several northeastern states are also exploring renewable sources such as
solar
energy to generate electricity for EVs. The EVermont Project is using a
successful solar-powered system to charge a mail delivery truck used at the
General Services Center in Middlesex, Vermont. A solar array was installed
and
wired into the system?s power grid. The solar array generates electricity
during the day and the truck charges at night. Overall, the solar panels
put
out more power than the truck uses on its daily rounds.18
The Efficiency Advantage of EVs and Power Plants
EVs recharging from fossil-fueled power plants such as coal and oil have
unique efficiency advantages over ICE vehicles. As a system, EVs and power
plants are twice as efficient as ICE vehicles and the system that refines
gasoline. See Table 4. Although there are losses associated with generating
electricity from fossil-based fuels, EVs are significantly more efficient
in
converting their energy into mechanical power.
Table 4. Operating Efficiency Comparison Between EVs and ICE Vehicles19
EVs and Power Plants vs ICE and Fuel Refining
Processing 39% 92%
(Electricity Generation) (Fuel Refining)
Transmission Lines 95% n/a
Charging n/a 88%
Vehicle Efficiency 88% 15%
Overall Efficiency 28% 14%
Since EVs operate more efficiently then their ICE-powered counterparts,
overall fuel economy is higher. However, making a direct comparison between
the fuel efficiencies of both vehicles is difficult. By applying a common
unit
of energy, such as British Thermal Units (Btus) we can get a fair
comparison
between the two.
For the following example we will compare the fuel efficiencies of a 1995
Acura 3.2 TL and GM?s new electric vehicle? the EV1. See Table 5. Both
vehicles cost about $34,000 and can accelerate from 0 to 60 mph in 8.5
seconds. Table 5. Fuel Efficiency Comparison Between EVs and ICE Vehicles20
Electric-Powered GM EV1 Gasoline-Powered Acura Start with 1 million Btus
Start
with 1 million Btus Energy left after generation (39% efficiency) 390,000
Btus
Energy left after refining (92% efficiency) 920,000 Btus Energy left after
charging losses (88% efficiency) 343,200 Btus Energy left after
transportation
(95% efficiency) 874,000 Btus Btus per Kilowatt-hour 3412 Btus21 Btus per
gallon of gasoline 115,400 Btus22 Electricity Available 100.6 kWhr Gallons
available 7.6 gallons Energy Efficiency .19 kWhr/mile Fuel economy 24 mpg
Miles per million Btus 529.5 miles Miles per million Btus 182.5 miles
Equivalent mpg 59 mpg23 Equivalent mpg 24 mpg
Even though the GM EV1 has 43 percent fewer Btus after electricity
generation,
it can be driven almost 350 miles farther because the vehicle is more
efficient than the Acura. In fact, the GM EV1 has the gasoline equivalency
of
59 mpg23 even after factoring in losses from electricity generation and
charging!
Scrubbing Out Power Plant Emissions
We?ve discussed how the system of power plants and EVs can improve air
quality, improve operating efficiencies, and save fuel, but just how
efficient
are power plant emissions controls?
Controlling emissions from several hundred power plants is much easier then
controlling the emissions from 187 million ICE vehicles. In fact, electric
utilities go through considerable efforts to monitor and remove emissions
from
their facilities. Teams of engineers carefully maintain the plants at peak
operating efficiency. State of the art equipment such as scrubbers are
installed to remove emissions. Electrostatic precipitators (ESPs) between
the
boilers and smokestacks remove up to 99.75 percent of the ash emitted by
power
plants. Coal-fired plants in Texas using ESPs remove up to 13.4 million
tons
of ash each year, releasing only 3000 tons into the atmosphere.24 The
amount
released falls below U.S. EPA regulations for ash emissions.
Over the next seven years, electric utilities in the Northeast are
committed
to reducing NOx emissions by 55 to 70 percent.25 When one power plant
upgrades
its emission controls, thousands of EVs immediatly reap the benefits from
this
improvement. Catalytic Clunkers Upgrading and maintaining emissions for ICE
vehicles is a different story. According to Drew Kodjak, a lawyer from
NESCAUM, ICE vehicles pollute more over time while power plants tend to
pollute less over time. Over the course of its lifetime, a gasoline car
will
spew out 60 times more CO, 30 times more VOC, and twice as much CO2 as
electric power plants.
The U.S. Environmental Protection Agency estimates that tailpipe emissions
increase 25 percent for every 10,000 miles traveled.26 As gasoline cars
age,
their engines, catalytic converters, and other emission control devices
become
less efficient. The cleanest a gasoline car ever will be is the day it
rolls
off the assembly line. The deterioration of emission control systems on ICE
vehicles can increase emissions up to 90 percent. To deal with increased
emissions, state governments have adopted emission inspection programs with
varied degrees of success. Many of these programs have been delayed due to
public concern for the cost of repairing emission components. In Maryland,
drivers can receive a waiver if they document attempts to repair their ICE
cars even though the cars continue to fail emission tests.
Newer cars entering the market are not necessarily the cleanest either. The
hottest vehicles on the market today are sport utility vehicles (SUV) which
now account for 40 percent of all new car sales. These gas guzzlers are
driving up this country?s demand for imported oil, decreasing overall fuel
efficiency, and increasing emissions.
Today?s Power Plants Meeting Tomorrow?s Recharging Needs
Many critics ask how this country could possibly support millions of EVs on
today?s existing power grid. The Electric Power Resource Institute (EPRI)
estimates that this country has the ability to support 50 million EVs
without
building any more power plants.
Another study puts this number closer to 20 million.27 Even so, 20 million
EVs
is only 10 percent of today?s fleet of 187 million cars. Thousands more
could
be added if they are charged at night during off-peak hours. Twenty million
EVs, each with 100,000 miles on the odometer, would reduce CO2 emissions in
this country by 500 million tons without building more power plants.
Southern California Edison (SCE) estimates that it has enough off-peak
capacity to refuel up to 2 million cars, 25 percent of the area?s
automobiles.
SCE estimates it will only need to add 200 megawatts of capacity by 2008 to
accommodate EVs.
Summary
In conclusion, EVs will have a considerable impact on reducing air
pollution,
improving fuel efficiency, and reducing our overall dependency on foreign
oil.
As power plants improve efficiency and turn to cleaner fuels such as
natural
gas and zero-emission sources, EVs will continue to be the best solution
towards attaining clean air.
Notes
1. Bob Brandt, Build Your Own Electric Car, (Tab Books, Blue Ridge Summit,
PA,
1994), Table 2-2, p. 35.
2. Evaporative emissions include fumes and gases that evaporate during
refueling, and fumes and gases from components of the engine, such as the
carburetor.
3. Bob Brandt goes one step further stating, ?There is no emission from an
electric vehicle and, until there exists an appreciable number of them
they do
not impact in any way the emissions from the power plant used to generate
the
electricity.? Bob Brandt, Build Your Own Electric Car, (Tab Books, Blue
Ridge
Summit, PA, 1994), p. 32.
4. Electric Power Research Institute, ?Electric Vehicle Infrastructure,?
Will
Electric Vehicles Contribute to a Cleaner Environment , (1992).
5. California Air Resources Board, Draft Technical Document for the Low-
Emission Vehicle and Zero-Emission Vehicle Workshop on March 25, 1994,
Zero-
Emission Vehicle Update, (1994), Table 1, p. 3.
6. Bob Brandt, Build Your Own Electric Car, (Tab Books, Blue Ridge Summit,
PA,
1994), p. 33.
7. Ibid, p. 31.
8. Timothy B. Wheeler, ?Smog risk greater than believed,? The Baltimore
Sun,
(March 5, 1995), Section C 1.
9. James J. MacKenzie, The Keys to the Car, (World Resources Institute,
Baltimore, Maryland, May 1994), p. 91.
10.James J. MacKenzie, The Keys to the Car, (World Resources Institute,
Baltimore, Maryland, May 1994), p. 92.
11.Daniel Sperling, ?The Case for Electric Vehicles,? Scientific American ,
(November 1996), article available from the Scientific American website,
http://www.sciam.com/1196issue/1196sperling.html
12.Drew Kodjak, ?EVs: Clean Today, Cleaner Tomorrow,? Technology Review,
(August/September 1996), p. 66-67.
13. California Air Resources Board, Draft Technical Document for the Low-
Emission Vehicle and Zero-Emission Vehicle Workshop on March 25, 1994,
Zero-
Emission Vehicle Update, (1994), Table C-6, p. 61.
14.Steve McCrea, Why Wait for Detroit, (South Florida Electric Vehicle Auto
Association, 1992), p. 39.
15. California Air Resources Board, Draft Technical Document for the Low-
Emission Vehicle and Zero-Emission Vehicle Workshop on March 25, 1994,
Zero-
Emission Vehicle Update, (1994), Table C-6, p. 68.
16.?Emissions, Quantifying the Air Quality Impact of EV Recharging,? Green
Car
Journal, (October 1993), p. 116.
17. Center for Technology Assessment Transportation Technology Review, ?CTA
Findings Reveal Carnegie-Mellon Study Misrepresents Environmental Impacts
of
Electric Vehicles,? (1995), p. 5.
18.Hilton Dier III, VT Electric Car Co.
19.Ovonic fact sheet, ?Fuel Efficiency Comparison.?
20.Table derived from ?Why Wait for Detroit,? Steve McCrea, (1992), p. 42.
In
the comparison, each vehicle is given 1 million Btus to start with. After
losses are factored in, the results are divided by the Btu equivalents of
kilowatt-hours (3,412 Btus/kWh) for the EV and gallons (114,500
Btus/gallon)
for the ICE car. These results are divided by the given efficiency for each
vehicle. The final results are miles each vehicle can travel.
21.Equivalent for 3,412 Btus per kilowatt hour obtained from CARB.
California
Air Resources Board, Draft Technical Document for the Low-Emission Vehicle
and
Zero-Emission Vehicle Workshop on March 25, 1994, Zero-Emission Vehicle
Update, (1994), p.72.
22.Equivalent for 114,500 Btus per gallon obtained from CARB. California
Air
Resources Board, Draft Technical Document for the Low-Emission Vehicle and
Zero-Emission Vehicle Workshop on March 25, 1994, Zero-Emission Vehicle
Update, (1994), p.72.
23.The formula for figuring equivalent mpg for the electric car is: 1)
Vehicle
Efficiency x Btus per kWh ÷ power plant efficiency = Btus per mile 2) Btus
per
mile ÷ charging efficiency = Btus per mile 3) Btus per gallon ÷ Btus per
mile
= mpg To obtain 59 mpg for EV substitute the numbers from Table 5. 1) 190
Wh/mi x 3.412 Btus /Wh ÷ 0.39 (power plant effic.) = 1662.25 Btus /mi 2)
1662.25 Btus /mi ÷ 0.88 (charging effic.) = 1955.58 Btus /mi 3) 114,500
Btus
/gal ÷ 1955.58 Btus /mi = 58.55 mpg
24. Central Southwest System Homepage, ?Air Quality,?
http://www.csw.com/er/airqual.html
25.Drew Kodjak, ?EVs: Clean Today, Cleaner Tomorrow,? Technology Review,
(August/September 1996), p. 66-67.
26.Ibid, p. 66-67.
27. Fortune Magazine, ?Electric Vehicles, Technology Recreates the
Automobile.? (Reprint from June 26, 1995)
Acknowledgments
Kevin Conners, Advocacy Institute; Kyle Davis, Southern California Edison;
Hilton Dier III, VT Electric Car Co.; Dave Goldstein President EVA/DC;
Monica
Gribben, EVA/DC; Jane Hathaway, NRDC; Jason Marks, Union of Concerned
Scientists; and David Rezachek, Ph.D., P.E.
David Roden - Akron, Ohio, USA
1991 Solectria Force 144vac
1991 Ford Escort Green/EV 128vdc
1970 GE Elec-trak E15 36vdc
1974 Avco New Idea 36vdc
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Cutting the space budget really restores my faith in humanity. It
eliminates dreams, goals, and ideals and lets us get straight to the
business of hate, debauchery, and self-annihilation.
-- Johnny Hart
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