Electric vehicles aren’t the solution - yet
AS THE SEARCH for climate solutions hastens, urgency should not undermine long-term sensibility. Ever-mounting climate change concerns and oil-driven foreign policy challenges, in the wake of $4-per-gallon gasoline, have generated a stampede toward electric vehicles. If one listens to clean-energy advocates, recovery-bill architects, electric utilities, and eager start-ups and their investors, one might think an electric vehicle silver bullet is just around the corner. But electric vehicles will not provide an easy or quick answer to environmental and economic woes. Forcing an electric vehicle solution too soon may preclude more thoughtful actions that would improve electric vehicle technology and reduce its cost.
Consider the benefits of electric vehicles. Electricity is cheap compared to gasoline, and it is little impacted by oil price swings. The United States has enough electricity supply capacity to handle battery recharging even if some two-thirds of the light-duty vehicle fleet were to become electric - assuming people recharged their vehicles at night.
Recharging would steadily begin to look much cleaner under a climate policy that incentivized the development and use of carbon-free electricity sources. Consumers might even find recharging more convenient than the hassle of locating a service station when they run out of gas - assuming they have easy access to an electric outlet and a few hours to spare. Performance-conscious drivers also just might grow attached to the quieter operation and impressive acceleration of electric vehicles. And the potential to reduce foreign oil imports and employ Americans in home-grown battery manufacturing jobs makes the cars popular in Washington.
However, switching to an electric vehicle world will not be quick or easy. The vehicles will be expensive for companies, consumers, and governments because they currently cost significantly more to produce than today’s gasoline vehicles. Battery replacement, if needed, could cost up to half of the price of a new vehicle. Consumers have shown a reluctance to making such large expenditures in the face of economic uncertainty.
Electric vehicles also have limited range, which means that, without a more flexible recharging solution, they may not meet the driving-distance requirements of a large swath of the population. Battery-swap stations are being explored, but their ultimate feasibility is unproven. New manufacturers trying to contend in this market face challenging problems of high initial cost, liabilities associated with new technology, and the need to prove reliability. Cracking these chicken-and-egg problems will take persistent effort and time.
Adding electric vehicles would have limited climate benefits in the near term. The US electric grid is heavily reliant on fossil fuels, so vehicles powered by today’s grid would offer minor, if any, reductions in greenhouse gases - especially compared with today’s off-grid hybrids, next-generation biofuels, expanded public transportation, and other alternatives. A climate policy, which will take time to phase in and promote change, or other incentives to clean up the electric grid, will be necessary in order to realize the full greenhouse gas reduction potential of using electricity in vehicles.
One option, the plug-in hybrid electric vehicle, overcomes the range problem and reduces cost by combining a moderate-size battery-motor propulsion system with a small internal combustion engine that can recharge the batteries while the car is being driven. Exploring the plug-in hybrid option as a step prior to full electrification seems wiser than committing to electric vehicles at the outset.
Perhaps more important, the United States needs policies that will incentivize the lowest cost solutions for reducing vehicles’ greenhouse gas emissions and petroleum consumption, instead of targeting the adoption of specific technologies. It is hard to predict what role electric vehicles will ultimately play. Electricity’s potential to displace petroleum and diversify transportation’s source of energy is one of the more promising options. However, realizing the benefits of electric vehicles will depend on relative costs, consumer preferences, and sustained policy commitments. Transforming the current stampede into a more measured and rational approach may be the key to continuing the march toward electricity and greener transportation.
John Heywood a is professor of mechanical engineering and director of the Sloan Automotive Laboratory at MIT. Valerie J. Karplus is a doctoral candidate in the engineering systems division at MIT. 
