Plug-In Hybrids: What's the Big Deal?
By Bill Moore
This article was originally published in the ASPO USA newsletter.
If General Motors was looking for a spike in its public perception as a competitive, socially responsible automotive innovator – read 'green' car company – then a little concept car bearing the Chevrolet badge and called, appropriately enough, Volt, appears to have resuscitated the fortunes of a company until recently considered terminal.
Rumored for months, GM nonetheless still surprised the automotive world with a roguish electric car that could mark a watershed in its future and a less bumpy ride down the road beyond Hubbert's Peak.
The Chevrolet Volt is a four-passenger, plug-in series electric car that will have the ability to run on any blend of gasoline to straight ethanol as most new cars in Brazil do today. GM calls this drive system E-Flex for electric flexible fuel.
I can only speculate as to what forces converged to cause GM to make this bold move: the highly successful Chris Paine documentary on the EV1 may have played a role, as did mounting political pressure from the Bush White House on down, to growing grass roots efforts like Plug-In America and Plug-In Partners, to a constant barrage of editorials coming out of conservative and national security think tanks around the Washington Beltway. Whatever the reasons, the company “Who Killed the Electric Car” has decided – with some caveats – to resurrect it, declaring it may even have it in production sometime between 2010 and 2012.
The theory behind the electric plug-in hybrid goes like this: since most Americans commute less than 40 miles a day, it is technologically feasible to power the vehicle that distance using batteries only, especially if those batteries are lithium-based. GM's original EV1 – the 'victim' in Paine's documentary – got between 60-80 miles range using century-old lead-acid battery chemistry, which was subsequently upgraded to nickel metal hydride and saw its driving range improve to 120 miles or better.
But instead of building an all-electric car like the EV1, which required a large, heavy and costly 26 kWh battery pack, GM engineers could short circuit the issue of limited range by giving owners the option to use battery energy for most of their daily driving needs. And rather than force the owner to wait hours to recharge the car, a small, internal combustion engine would be mated to an electrical generator that produces enough electrical power to recharge the battery and drive the vehicle at freeway speeds. GM estimates that in this mode the car will still get 50 mpg; in electric mode it could be as high as 150 mpg or as GM Co-Chairman Bob Lutz likes to point out, using E85 ethanol is equivalent to getting 500 miles per gallon gasoline, though that's probably more hyperbole than reality.
GM estimates the Volt has a driving range of 640 miles, enough to go from Detroit to D.C. on a single, 12 gallon tank of fuel, and that since 78% of Americans drive 40 miles or less each day, they may use little if any gasoline or ethanol five days out of the week. We'd all just plug the cars in at night like our mobile phones and wake up the next morning with a full charge in the battery.
GM isn't alone investigating and/or actively developing electric plug-in hybrid technology. Ford not only debuted its Airstream plug-in hybrid concept minivan at the 2007 North American International Auto Show, but it also pulled the cover off its Edge plug-in hybrid crossover vehicle at the Washington, D.C. Auto Show. Toyota officials have admitted that they too are exploring plug-in hybrids, spurred on, in part, by entrepreneurs who have modified the popular Prius into plug-in vehicles. There are about half-a- dozen groups actively involved in performing these conversions, substituting off-the-shelf lithium and nickel metal hydride batteries for the one already in the Prius. New York State has allocated $10 million to convert as many of its own Priuses to plug-ins as financially feasible.
But therein lies the rub.
Lithium ion batteries are expensive, costing thousands of dollars for battery packs of sufficient capacity to propel a car any appreciable distance on electricity only. The 1.4kWh battery in the current model Prius will move it only a couple kilometers at most and at no more than 35 mph. To travel 40 miles at 60-70 mph, GM engineers estimate the Volt will need a 16 kWh pack. At the moment, advanced batteries like NiMH and Li-ion are reported to cost between $150-300 per kilowatt hour of stored energy (http://eetdnews.lbl.gov/nl17/battupdate.html), or $2400-4800 per battery pack, and those figures are probably low, very low. A much higher number – something in the $350 kWh or higher range -- is probably closer to the truth. Start-up, advanced battery manufacturers are careful to omit any reference to the cost per kilowatt hour of their batteries, arguing that until they can achieve scales of production, such numbers wouldn't reflect the potentially far lower costs made possible by automated, mass-production.
Companies that offer conversions of Toyota Priuses and Ford Escape Hybrids say they are hoping to sometime soon offer kits for around $12,000, the largest percentage of which is the cost of the batteries. Admittedly, this is too steep a threshold for the average car buyer, so GM, Ford, Toyota and other carmakers will have to innovate everywhere they can to cut this cost premium down to somewhere closer to price of the fuel saved.
There is one other potential "fly in the ointment" of this electric dream: the availability of lithium itself. A European research firm, Meridian International Research (MIR), has carefully examined the world supply and production of lithium carbonate and had raised some serious concerns about how much we can depend on this lightest of all metals. Like oil, the majority of the world's lithium carbonate is found in just two key areas: the Andian Altiplano and Chinese-controlled Tibet. And also like oil, known world reserves are limited, perhaps less than 7 million tons. U.S. reserves are now 40 years old and in decline. MIR sees two other battery chemistries -- sodium nickel chloride and zinc air -- as ultimately offering a way around the lithium supply issue. The raw materials for these are in abundant supply globally with plenty of production capacity to meet automotive battery demands in the future.
Assuming the large OEMs and their suppliers can solve the technical and economic issues, plug-in hybrids can make a serious dent in our oil consumption by shifting to indigenous fuels like coal, hydro, natural gas, and nuclear. Plug-ins also lend themselves well to integration with renewable energy like wind, which in some regions like West Texas tends to blow at night when the grid doesn't need the power. Austin Energy in Austin, Texas has actively evangelized the concept largely for this reason. It hopes to someday use night-time electric power from distance wind farms to recharge its customer's plug-in hybrids, making them virtually pollution free.
Finally, according to a recent study by the DOE's Pacific Northwest National Lab, there is enough under-utilized, overnight electric power capacity to charge more than 80% of the United States automotive fleet if they were all plug-in hybrids or pure electric cars.
It's an exciting vision, though one that isn't going to be easy to achieve. It will require breakthroughs in technology, manufacturing, public policy and most importantly, political will.
Bill Moore is the founder and publisher of EVWorld.Com, which he launched in 1998. He began writing about transportation technology in 1986 with the publication of "Secrets of the Black Boxes" in Discover magazine.
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