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Unclean at any speed
http://spectrum.ieee.org/energy/renewables/unclean-at-any-speed Last summer, California highway police pulled over pop star Justin Bieber
as he sped through Los Angeles in an attempt to shake the paparazzi. He
was driving a hybrid electric car—not just any hybrid, mind you, but a
chrome-plated Fisker Karma,
a US $100 000 plug-in hybrid sports sedan he’d received as an
18th-birthday gift from his manager, Scooter Braun, and fellow singer
Usher. During an on-camera surprise presentation, Braun remarked, “We
wanted to make sure, since you love cars, that when you are on the road
you are always looking environmentally friendly, and we decided to get
you a car that would make you stand out a little bit.” Mission
accomplished.
Bieber joins a growing list of celebrities, environmentalists, and
politicians who are leveraging electric cars into green credentials.
President Obama once dared to envision 1 million electric cars plying
U.S. roads by 2015. London’s mayor, Boris Johnson, vibrated to the press
over his born-again electric conversion after driving a Tesla Roadster,
marveling how the American sports coupe produced “no more noxious
vapours than a dandelion in an alpine meadow.” Meanwhile,
environmentalists who once stood entirely against the proliferation of
automobiles now champion subsidies for companies selling electric cars
and tax credits for people buying them.
Two dozen governments around the world subsidize the purchase of
electric vehicles. In Canada, for example, the governments of Ontario
and Quebec pay drivers up to C $8500 to drive an electric car. The
United Kingdom offers a £5000 Plug-in Car Grant. And the U.S. federal
government provides up to $7500 in tax credits for people who buy
plug-in electric vehicles, even though many of them are affluent enough
not to need such help. (The average Chevy Volt owner, for example, has
an income of $170 000 per year.)
Some states offer additional tax incentives. California brings the
total credit up to $10 000, and Colorado to $13 500—more than the base
price of a brand new Ford Fiesta. West Virginia offers the sweetest
deal. The state’s mining interests are salivating at the possibility of
shifting automotive transportation from petroleum over to coal.
Residents can receive a total credit of up to $15 000 for an
electric-car purchase and up to $10 000 toward the cost of a personal
charging station.
There are other perks. Ten U.S. states open the high-occupancy lanes of
their highways to electric cars, even if the car carries a lone driver.
Numerous stores offer VIP parking for electric vehicles—and sometimes a
free fill-up of electrons. Mayor Johnson even moved to relieve
electric-car owners of the burden of London’s famed congestion fee.
Alas, these carrots can’t overcome the reality that the prices of
electric cars are still very high—a reflection of the substantial
material and fossil-fuel costs that accrue to the companies constructing
them. And some taxpayers understandably feel cheated that these
subsidies tend to go to the very rich. Amid all the hype and hyperbole,
it’s time to look behind the curtain. Are electric cars really so green? The idea of electrifying automobiles to get around
their environmental shortcomings isn’t new. Twenty years ago, I myself
built a hybrid electric car that could be plugged in or run on natural
gas. It wasn’t very fast, and I’m pretty sure it wasn’t safe. But I was
convinced that cars like mine would help reduce both pollution and
fossil-fuel dependence.
I was wrong.
I’ve come to this conclusion after many years of studying environmental
issues more deeply and taking note of some important questions we need
to ask ourselves as concerned citizens. Mine is an unpopular stance, to
be sure. The suggestive power of electric cars is a persuasive force—so
persuasive that answering the seemingly simple question “Are electric
cars indeed green?” quickly gets complicated.
As with most anything else, the answer depends on whom you ask. Dozens
of think tanks and scientific organizations have ventured conclusions
about the environmental friendliness of electric vehicles. Most are
supportive, but a few are critical. For instance, Richard Pike of the Royal Society of Chemistry
provocatively determined that electric cars, if widely adopted, stood
to lower Britain’s carbon dioxide emissions by just 2 percent, given the
U.K.’s electricity sources. Last year, a U.S. Congressional Budget
Office study found that electric car subsidies “will result in little or
no reduction in the total gasoline use and greenhouse-gas emissions of
the nation’s vehicle fleet over the next several years.”
Source: WikipediaGenerous EV Incentives: Governments
around the world offer drivers various inducements to buy electric
cars. The monetary incentives in western Europe, for example, include
direct subsidies on vehicle purchases as well as certain tax exemptions.
Some of these countries also provide the drivers of electric cars with
free parking and other perks.
Others are more supportive, including the Union of Concerned Scientists. Its 2012 report [PDF] on the issue, titled “State of Charge,” notes that charging electric cars yields less CO2
than even the most efficient gasoline vehicles. The report’s senior
editor, engineer Don Anair, concludes: “We are at a good point to clean
up the grid and move to electric vehicles.”
Why is the assessment so mixed? Ultimately, it’s because this is not
just about science. It’s about values, which inevitably shape what
questions the researchers ask as well as what they choose to count and
what they don’t. That’s true for many kinds of research, of course, but
for electric cars, bias abounds, although it’s often not obvious to the
casual observer.
To get a sense of how biases creep in, first follow the money. Most
academic programs carrying out electric-car research receive funding
from the auto industry. For instance, the Plug-in Hybrid and Electric Vehicle Research Center
at the University of California, Davis, which describes itself as the
“hub of collaboration and research on plug-in hybrid and electric
vehicles for the State of California,” acknowledges on its website
partnerships with BMW, Chrysler-Fiat, and Nissan, all of which are
selling or developing electric and hybrid models. Stanford’s Global Climate & Energy Project,
which publishes research on electric vehicles, has received more than
$113 million from four firms: ExxonMobil, General Electric,
Schlumberger, and Toyota. Georgetown University, MIT, the universities
of Colorado, Delaware, and Michigan, and numerous other schools also
accept corporate sponsorship for their electric-vehicle research.
I’m not suggesting that corporate sponsorship automatically leads
people to massage their research data. But it can shape findings in more
subtle ways. For one, it influences which studies get done and
therefore which ones eventually receive media attention. After all,
companies direct money to researchers who are asking the kinds of
questions that stand to benefit their industry. An academic who is
studying, say, car-free communities is less likely to receive corporate
funding than a colleague who is engineering vehicle-charging stations.
Many of the researchers crafting electric-vehicle studies are eager
proponents of the technology. An electric-vehicle report from Indiana University’s School of Environmental Affairs,
for instance, was led by a former vice president of Ford. It reads like
a set of public relations talking points and contains advertising
recommendations for the electric-car industry (that it should manage
customers’ expectations, to avoid a backlash from excessive claims).
Even the esteemed Union of Concerned Scientists clad its electric-car
report in romantic marketing imagery courtesy of Ford, General Motors,
and Nissan, companies whose products it evaluates. Indeed, it’s very
difficult to find researchers who are looking at the environmental
merits of electric cars with a disinterested eye. So how do you gauge the environmental effects of
electric cars when the experts writing about them all seem to be
unquestioned car enthusiasts? It’s tough. Another impediment to
evaluating electric cars is that it’s difficult to compare the various
vehicle-fueling options. It’s relatively easy to calculate the amount of
energy required to charge a vehicle’s battery. It isn’t so
straightforward, however, to compare a battery that’s been charged by
electricity from a natural-gas-fired power plant with one that’s been
charged using nuclear power. Natural gas requires burning, it produces
CO2, and it often demands environmentally problematic methods
to release it from the ground. Nuclear power yields hard-to-store
wastes as well as proliferation and fallout risks. There’s no clear-cut
way to compare those impacts. Focusing only on greenhouse gases, however
important, misses much of the picture.
Manufacturers and marketing agencies exploit the fact that every power
source carries its own unique portfolio of side effects to create the
terms of discussion that best suit their needs. Electric-car makers like
to point out, for instance, that their vehicles can be charged from
renewable sources, such as solar energy. Even if that were possible to
do on a large scale, manufacturing the vast number of photovoltaic cells
required would have venomous side effects. Solar cells contain heavy
metals, and their manufacturing releases greenhouse gases such as sulfur
hexafluoride, which has 23 000 times as much global warming potential
as CO2, according to the Intergovernmental Panel on Climate Change.
What’s more, fossil fuels are burned in the extraction of the raw
materials needed to make solar cells and wind turbines—and for their
fabrication, assembly, and maintenance. The same is true for the
redundant backup power plants they require. And even more fossil fuel is
burned when all this equipment is decommissioned. Electric-car
proponents eagerly embrace renewable energy as a scheme to power their
machines, but they conveniently ignore the associated environmental
repercussions.
Finally, most electric-car assessments analyze only the charging of the
car. This is an important factor indeed. But a more rigorous analysis
would consider the environmental impacts over the vehicle’s entire life
cycle, from its construction through its operation and on to its
eventual retirement at the junkyard. One study attempted to
paint a complete picture. Published by the National Academies in 2010
and overseen by two dozen of the United States’ leading scientists, it
is perhaps the most comprehensive account of electric-car effects to
date. Its findings are sobering.
Illustration: Bryan Christie DesignWhat’s in your EV?
Don’t just think about the missing tailpipe. Manufacturing the
specialized components that go into electric cars, such as the Nissan
Leaf, has significant environmental costs.
It’s worth noting that this investigation was commissioned by the U.S.
Congress and therefore funded entirely with public, not corporate,
money. As with many earlier studies, it found that operating an electric
car was less damaging than refueling a gasoline-powered one. It isn’t
that simple, however, according to Maureen Cropper,
the report committee’s vice chair and a professor of economics at the
University of Maryland. “Whether we are talking about a conventional
gasoline-powered automobile, an electric vehicle, or a hybrid, most of
the damages are actually coming from stages other than just the driving
of the vehicle,” she points out.
Part of the impact arises from manufacturing. Because battery packs are
heavy (the battery accounts for more than a third of the weight of the
Tesla Roadster, for example), manufacturers work to lighten the rest of
the vehicle. As a result, electric car components contain many
lightweight materials that are energy intensive to produce and
process—carbon composites and aluminum in particular. Electric motors
and batteries add to the energy of electric-car manufacture.
In addition, the magnets in the motors of some electric vehicles
contain rare earth metals. Curiously, these metals are not as rare as
their name might suggest. They are, however, sprinkled thinly across the
globe, making their extraction uneconomical in most places. In a study released last year,
a group of MIT researchers calculated that global mining of two rare
earth metals, neodymium and dysprosium, would need to increase 700
percent and 2600 percent, respectively, over the next 25 years to keep
pace with various green-tech plans. Complicating matters is the fact
that China, the world’s leading producer of rare earths, has been
attempting to restrict its exports of late. Substitute strategies exist,
but deploying them introduces trade-offs in efficiency or cost.
The materials used in batteries are no less burdensome to the
environment, the MIT study noted. Compounds such as lithium, copper, and
nickel must be coaxed from the earth and processed in ways that demand
energy and can release toxic wastes. And in regions with poor
regulations, mineral extraction can extend risks beyond just the workers
directly involved. Surrounding populations may be exposed to toxic
substances through air and groundwater contamination.
At the end of their useful lives, batteries can also pose a problem. If
recycled properly, the compounds are rather benign—although not
something you’d want to spread on a bagel. But handled improperly,
disposed batteries can release toxic chemicals. Such factors are
difficult to measure, though, which is why they are often left out of
studies on electric-car impacts.
The National Academies’ assessment didn’t ignore those
difficult-to-measure realities. It drew together the effects of vehicle
construction, fuel extraction, refining, emissions, and other factors.
In a gut punch to electric-car advocates, it concluded that the
vehicles’ lifetime health and environmental damages (excluding long-term
climatic effects) are actually greater than those of
gasoline-powered cars. Indeed, the study found that an electric car is
likely worse than a car fueled exclusively by gasoline derived from
Canadian tar sands!
As for greenhouse-gas emissions and their influence on future climate,
the researchers didn’t ignore those either. The investigators, like many
others who have probed this issue, found that electric vehicles
generally produce fewer of these emissions than their gasoline- or
diesel-fueled counterparts—but only marginally so when full life-cycle
effects are accounted for. The lifetime difference in greenhouse-gas
emissions between vehicles powered by batteries and those powered by
low-sulfur diesel, for example, was hardly discernible.
The National Academies’ study stood out for its comprehensiveness, but it’s not the only one to make such grim assessments. A Norwegian study published last October in the Journal of Industrial Ecology
compared life-cycle impacts of electric vehicles. The researchers
considered acid rain, airborne particulates, water pollution, smog, and
toxicity to humans, as well as depletion of fossil fuel and mineral
resources. According to coauthor Anders Stromman, “electric vehicles
consistently perform worse or on par with modern internal combustion
engine vehicles, despite virtually zero direct emissions during
operation.”
Earlier last year, investigators from the University of Tennessee studied five vehicle types
in 34 Chinese cities and came to a similar conclusion. These
researchers focused on health impacts from emissions and particulate
matter such as airborne acids, organic chemicals, metals, and dust
particles. For a conventional vehicle, these are worst in urban areas,
whereas the emissions associated with electric vehicles are concentrated
in the less populated regions surrounding China’s mostly coal-fired
power stations. Even when this difference of exposure was taken into
account, however, the total negative health consequences of electric
vehicles in China exceeded those of conventional vehicles.
North American power station emissions also largely occur outside of
urban areas, as do the damaging consequences of nuclear- and fossil-fuel
extraction. And that leads to some critical questions. Do electric cars
simply move pollution from upper-middle-class communities in Beverly
Hills and Virginia Beach to poor communities in the backwaters of West
Virginia and the nation’s industrial exurbs? Are electric cars a sleight
of hand that allows peace of mind for those who are already comfortable
at the expense of intensifying asthma, heart problems, and radiation
risks among the poor and politically disconnected?
Source: National Academies PressThey all pollute: Even
assuming 2030 vehicle technology and grid enhancements, the National
Academies concluded that the health and nonclimate damage from electric
cars would still exceed the damage from conventional fueling options.
The hope, of course, is that electric-car technology and power grids
will improve and become cleaner over time. Modern electric-car
technology is still quite young, so it should get much better. But don’t
expect batteries, solar cells, and other clean-energy technologies to
ride a Moore’s Law–like curve of exponential development. Rather,
they’ll experience asymptotic growth toward some ultimate efficiency
ceiling. When the National Academies researchers projected technology
advancements and improvement to the U.S. electrical grid out to 2030,
they still found no benefit to driving an electric vehicle.
If those estimates are correct, the sorcery surrounding electric cars
stands to worsen public health and the environment rather than the
intended opposite. But even if the researchers are wrong, there is a
more fundamental illusion at work on the electric-car stage. All of the aforementioned studies compare electric
vehicles with petroleum-powered ones. In doing so, their findings draw
attention away from the broad array of transportation options
available—such as walking, bicycling, and using mass transit.
There’s no doubt that gasoline- and diesel-fueled cars are expensive
and dirty. Road accidents kill tens of thousands of people annually in
the United States alone and injure countless more. Using these kinds of
vehicles as a standard against which to judge another technology sets a
remarkably low bar. Even if electric cars someday clear that bar, how
will they stack up against other alternatives?
For instance, if policymakers wish to reduce urban smog, they might
note that vehicle pollution follows the Pareto principle, or 80-20 rule.
Some 80 percent of tailpipe pollutants flow from just 20 percent of
vehicles on the road—those with incomplete combustion. Using engineering
and remote monitoring stations, communities could identify those cars
and force them into the shop. That would be far less expensive and more
effective than subsidizing a fleet of electric cars.
If legislators truly wish to reduce fossil-fuel dependence, they could
prioritize the transition to pedestrian- and bike-friendly
neighborhoods. That won’t be easy everywhere—even less so where the
focus is on electric cars. Studies from the National Academies point to
better land-use planning to reduce suburban sprawl and, most important,
fuel taxes to reduce petroleum dependence. Following that prescription
would solve many problems that a proliferation of electric cars could
not begin to address—including automotive injuries, deaths, and the
frustrations of being stuck in traffic.
Upon closer consideration, moving from petroleum-fueled vehicles to
electric cars begins to look more and more like shifting from one brand
of cigarettes to another. We wouldn’t expect doctors to endorse such a
thing. Should environmentally minded people really revere electric cars?
Perhaps we should look beyond the shiny gadgets now being offered and
revisit some less sexy but potent options—smog reduction, bike lanes,
energy taxes, and land-use changes to start. Let’s not be seduced by
high-tech illusions. This article originally appeared in print as “Unclean at Any Speed.”
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