A plug-in hybrid electric car with an ultracapacitor.
http://www.salon.com/news/feature/2008/01/22/plug_in_hybrids/---
|
The Prius? Nope. Hydrogen? Forget about it. Plug-in hybrids are the only way to drive By Joseph Romm
|
|
---
The car of the future is here
---
http://www.salon.com/news/feature/2008/01/22/plug_in_hybrids/print.html
The car of the future is here
The Prius? Nope. Hydrogen? Forget about it. Plug-in hybrids are the only way to drive.
By Joseph Romm
Jan. 22, 2008 |
When is someone going to offer a practical and affordable family car
that runs on something other than oil and that sharply reduces both
greenhouse gas emissions and your fuel bill? A few weeks ago, I test-drove this mythical car of the future, a plug-in hybrid electric vehicle whose mass production might be only a few years away.
The Extreme Hybrid from AFS
Trinity was rolled out last week at the Detroit auto show. It can run
40 miles on electricity before reverting to running efficiently on
gasoline like a normal hybrid, such as the Toyota Prius.
Because the majority of people drive less than 40 miles a day, that car
can replace most weekly gasoline use, even if it is charged only once a
day. The fuel cost per mile, while running on electricity, is under
one-third the current cost of gasoline. A full overnight charge might
cost a dollar. The car accelerates like a cheetah, though quietly.
Time is running out on developing a truly energy-efficient car.
Accelerated burning of fossil fuels is bringing us closer to the
tipping point of irreversible climate catastrophe.
We are likely to peak soon in the production of conventional oil -- so
gasoline prices are inevitably headed higher in the coming decades.
Meanwhile, the cars we build today stay on the road more than 15 years,
so we have no time to waste.
You can buy a flexible fuel vehicle today that runs on 85 percent
ethanol and 15 percent gasoline, and you might even be able to find an
E85 station in your city. But corn ethanol
is far from a desirable alternative fuel. It doesn't significantly
reduce greenhouse gas emissions, or your fuel bill. That would require
low-carbon ethanol from biomass such as switchgrass, so-called
cellulosic ethanol, but the country does not have a single commercial
cellulosic ethanol facility. It will probably be at least 15 years --
and possibly twice that long -- before we have large volumes of
cellulosic biofuels for sale nationwide at an affordable price.
Hydrogen cars are even farther away from being practical.
Carbon-free hydrogen is likely to be more expensive than gasoline for a
long time. And the cost of building a carbon-free hydrogen fueling
infrastructure is several hundreds of billions, if not more than a
trillion, dollars.
Only one zero-carbon alternative fuel is substantially cheaper than
gasoline: electricity from renewable sources (or nuclear power). Of
course, you'd need a car that runs on electricity, and many people have
thought that you would need a technological breakthrough, or at least a
major advance in battery technology, to make that practical.
But game-changing breakthroughs in the energy sector are rare indeed.
One can wait a lifetime for a major new technology that fundamentally
alters the way we use energy. That's why the Extreme Hybrid, whose
electric technology is available today, is so exciting.
We saw all-electric cars in the 1990s, but they failed for a variety of reasons, as explained in the movie "Who Killed the Electric Car?"
One problem is that giving an electric car a 200-mile range requires a
lot of batteries, which adds weight, takes up space, and increases
cost. Plus, it takes hours to fill one up, so if you run out of juice,
you are stuck, making it impractical as a primary family car.
Ultimately, it lacked support by the very car companies, like General
Motors, that built it in the first place.
Everything changed with the success of hybrid-electric cars like the
Prius, which combine a gasoline engine with a battery and electric
motor. These hybrids charge the battery with energy regenerated during
braking or from the gas engine. They prove that a car combining gas and
electric drives can be practical and affordable and even desirable.
Some groups have been retrofitting Priuses to make them plug-ins,
providing the best of both worlds -- acting as an electric car for
local trips, but keeping the gas tank and engine for long trips and
quick refueling.
The key obstacle to building a practical plug-in hybrid has been the
battery. Not only do you need a lot more batteries for a plug-in than
for a simple hybrid, you need batteries with substantially different
capability. Gasoline hybrids mostly need batteries that can provide a
lot of power when necessary -- such as for accelerating onto a highway
-- as opposed to batteries that can store a lot of energy, which is
what is required to go relatively long distances after a single
charging. Designing a single battery that can store a lot of energy and
handle power surges is no easy task, especially when that battery must
be compact, affordable and safe as it constantly cycles through various
uses.
The New York Times describes the problem using this unintentionally amusing mixed metaphor:
"In
fact, the problem in a hybrid is not only how much energy the batteries
hold, a quality called energy density, but how fast they can deliver
it, called power density. The difference between energy density and
power density is like the difference between a wine jug and a peanut
butter jar -- the containers may have the same capacity, but the size
of their openings differ greatly."
Note to NYT: When describing a power battery that can deliver energy
in short, quick bursts, "peanut butter" is not the best analogy. A
shaken bottle of champagne might be better.
Regular hybrids were made practical by the development of the nickel
metal hydride battery, due in large part to a government-funded
research consortium. The prototype or demonstration hybrids built to
date have tended to use the more expensive, but more powerful and
compact, lithium-ion batteries popularized by the electronics industry.
Yet discharging a battery too rapidly, especially the current
generation of relatively inexpensive lithium-ion batteries such as are
found in laptops and cellphones, can damage it, degrading its lifetime.
The question has been: When will we have an affordable, safe, compact
and long-lived lithium-ion battery that can deliver both energy (for
range) and power (for acceleration) sufficient for a practical car?
The failure to find such a battery is a main reason Toyota and GM
have been slow to commit to offering a plug-in to consumers. At the
recent Detroit auto show, Toyota said it would offer a plug in by 2010,
although at first only to governments and corporations, not to
consumers. GM, which for much of the past year has been promising to
deliver the plug-in Chevy Volt in commercial quantities in 2010, has
recently said that 2010 remains only a goal -- no promises.
So how has AFS Trinity bypassed the need for a new lithium-ion
battery? Instead of waiting for a battery that can deliver both energy
and power cheaply, it uses current lithium-ion batteries for energy,
and then adds something called an ultracapacitor for rapid discharge
during acceleration.
Ultracaps have 10 to 100 times the power density of typical
batteries, but only one-tenth the energy density, so this is a marriage
made in heaven, or at least Silicon Valley. The ultracap is the
electrical equivalent of the shaken champagne bottle -- although even
that analogy is flawed since ultracaps do not just discharge quickly,
they also charge quickly. That's another benefit that ultracaps bring
to hybrids.
Regular hybrids get much of their efficiency gains from their
ability to capture the energy normally lost during braking and convert
it to electricity. Current hybrid batteries take up only about half of
this electricity, but fast-acting ultracaps can take up much more.
AFS Trinity is not an auto company. It applied its technology to
retrofit a Saturn Vue hybrid crossover vehicle, with the help of a
leading auto engineering company, Ricardo.
It believes that with mass production, an Extreme Hybrid would cost
only $9,000 more than an ordinary hybrid, with a payback of the extra
cost in fuel savings in under four years at current gas prices. But
that will require the company to find a major auto-manufacturing
partner willing to commercialize the vehicle.
Of course, like many small companies with great technology that I've
seen over the years, AFS Trinity may not succeed in achieving mass
production or meeting its cost targets. That said, I think the
importance of the Extreme Hybrid is that it shows there's more than one
possible strategy for making a practical plug-in, significantly
increasing the chances that someone will succeed.
Plug-ins are not a global warming solution by themselves. The
current electric grid is half coal power, so when plug-ins are running
on conventional grid power, they cut net greenhouse gas emissions by
perhaps one-third, compared to a regular hybrid running on gasoline.
They would, however, cut emissions by well over half compared to a conventional vehicle.
The big greenhouse gas savings would come about as plug-ins enable a
major transition toward clean electricity and away from petroleum-based
fuel, which is getting dirtier every year, as unconventional oil, such
as Canadian tar sands, becomes more popular.
Unlike petroleum, electricity is poised to get greener in the
future, especially as we fight climate change. Indeed, once we have a
national cap on carbon emissions, plug-ins will drive even faster
growth of the diverse and growing numbers of carbon-free electricity
sources, which include solar photovoltaics, solar thermal electric,
wind, geothermal, nuclear and, potentially, coal with carbon capture
and storage. By providing distributed energy storage to the grid,
plug-ins could make intermittent renewables like wind power (mostly
available at night) more cost-effective -- and ultimately assist
renewables in becoming the nation's primary source of power.
Also, if in a few years you were buying a plug-in hybrid, which
might last until 2030, you can safely bet that gasoline prices then are
going to be much higher than today's $3 a gallon. So plug-ins will be
the best hedge money can buy against oil shocks. Also, given that most
early adopters of plug-ins are likely to be environmentally conscious,
I would expect many of them to run their hybrids on 100 percent
renewable power, making plug-ins a major carbon reducer from the start.
Preventing catastrophic climate change will require the average U.S.
car and SUV to have 80 percent to 90 percent lower carbon dioxide
emissions by 2050, compared to current vehicles (the same for trucks,
airplanes and ships). Plug-ins could be an essential enabler of such
deep reductions. They can easily be made flexible-fuel vehicles, so if
low-carbon cellulosic biofuels prove practical and affordable, they can
be the primary liquid fuel for longer trips. Absent high-efficiency
vehicles like plug-ins, it is unlikely we will have enough spare arable
land and water in 2050 for cellulosic biofuels to provide sufficient
fuel to achieve such deep reductions across the entire transportation
sector.
Another key point is that most of the growth in car use in the
coming decades will come in countries where people don't necessarily
drive long distances on a regular basis -- and don't require large
SUVs. I believe that an affordable and purely electric car with a range
of 200 miles, even one with 100 miles, will be a successful primary car
for most people in most other countries. Plug-ins can help enable that
transition by reducing the cost of batteries and electronics.
Plug-ins may not suffer from a problem that has plagued so many
alternative fuel vehicles -- high initial cost. As I told AFS Trinity,
I wouldn't recommend designing the first plug-ins with a 40-mile
all-electric range. For many people, including me, that represents a
capability they are unlikely to use most days, meaning we would be
paying for a lot of unnecessary batteries and other electronics. You
could cut the cost of the first plug-ins by thousands of dollars if the
cars just had a 20-mile all-electric range.
I expect many early adopters will be able to charge their cars
twice: at home during the night and at work during the day. Companies
like Google, which aggressively supports the development of plug-ins,
will surely give its workers a large incentive to buy a plug-in,
powered by a charging station at its headquarters that draws on
renewable energy. Utilities will be eager to set up charging stations
at public places like malls and parking garages. Yes, you would
probably not be able to charge for a couple of hours during peak demand
on the hottest summer days, but that would still leave you plenty of
opportunity to charge your car during the day as well as the night.
That means a plug-in with a 20-mile all-electric range would still
allow many commuters to drive 40 miles or more on electricity, again
significantly reducing batteries, electronics and cost.
Also, a utility or other intermediary might lease a plug-in hybrid
-- or at least its battery -- to a consumer or business willing to
leave the vehicle connected when it was not on the road and to permit
the utility to control when the vehicle's battery was charged (and
possibly when it was discharged). This would provide the utility with a
new source of revenue and the consumer with a far less expensive car. A
related possibility is being pursued by many companies: Plug-in hybrids
could be charged at off-peak times and provide power and voltage to the
grid when needed. Vehicle owners may be able to get a rebate or revenue
stream from electric utilities for this service.
No country has ever delivered a mass-market alternative fuel vehicle
without government mandates. Plug-ins will no doubt need initial help,
although they probably require less government intervention than other
alternative fuels since they don't require an entirely new fueling
infrastructure. To spur their development, Brookings Institution
scholar and White House veteran David Sandalow
recommends that the federal government buy 30,000 plug-ins at an $8,000
premium. He suggests that the government offer an $8,000 consumer tax
credit for purchasers of the first million plug-ins, and a $4,000
rebate for purchasers of the second million.
These steps would speed the day when we have a practical plug-in hybrid. And that now seems closer than ever.
-- By Joseph Romm
====end of article====
cheers,
eco mann,
MMM (Global Million Marijuana March):
http://cannabis.wikia.com/wiki/Global_Marijuana_March_2008
http://en.wikipedia.org/wiki/Global_Marijuana_Marchhttp://gallery.marihemp.com/mmmhttp://www.myspace.com/ecommm
http://health.groups.yahoo.com/group/mmmworldhttp://health.groups.yahoo.com/group/cannabisaction __._,_.___
__,_._,___
RSS Feed