An Almost All-Electric Car?

Watch for the upcoming plug-in hybrid battle between GM and Toyota

3 min read

Remember General Motors’ all-electric plugâ''in vehicle, the EV1? It went to market in 1997, mostly in California, became a Hollywood and media darling, and ­vanished without a trace six years later after a paltry 1000 eâ''cars were leased. Depending on your ­political persuasion and ­tolerance for conspiracy theories, the car-killing forces included fickle consumer interest, poor battery life, corporate greed, global oil agendas, and government ineptitude. Who Killed the Electric Car? , a 2006 ­documentary, cinematically indicted all of the above, and more, for terminating interest in electric-­vehicle programs worldwide.

Well, despite all the postâ''EV1 talk that America’s ­premier ­automaker had ­cynically ­jettisoned its electric and ­alternative-fuel dreams to ­pursue gas-­guzzling SUV cash cows, GM seems never to have ­abandoned the e-car game. This time the auto­maker’s back with some ­economical gas/electric hybrids and fuel-cell vehicles, including a fuel-cell SUV. But the big news is GM’s snappy new hybrid plug-in ­technology, used in the Chevrolet Volt ­concept car, which some are touting as the Toyota killer.

Responding to ­heightened global concerns about ­greenhouse-gas emissions—and a new Washington ­mandate requiring cars to ­average 35 miles per ­gallon (6.7 liters per 100 ­kilometers) by 2020—both GM, the No. 1 ­automaker, and Toyota, the heir ­apparent, have said they hope to have ­different but ­affordable, ­efficient plug-in hybrid ­vehicles (or PHEVs) on the lot by 2011 [see my article "Top 10 Tech Cars" in this issue to learn more about what's ­happening this year]. In the looming plug-in battle royal, whose electric/combustion ­technology will carry the day?

Toyota has bet 10 years, untold billions, and its future product direction on what’s called the power-split hybrid. It has essentially the same design as mechanical-drive cars but uses both combustion and electricity for power, optimized by ­control algorithms. Toyota’s plug-in version of the powerâ''split hybrid has a bigger battery and can be recharged from a regular household power outlet. It runs short distances on electricity only, and then the combustion engine switches on, powering the car along with the batteries.

GM is betting on the series plug-in hybrid; Toyota is betting on the power-split plug-in hybrid. Tens of billions of dollars are at stake

GM, on the other hand, is staking its long-term direction on the series hybrid, which can also be recharged from a wall outlet. The car runs on full electricity until its batteries are nearly empty, and then its combustion engine starts up to run a backup generator that recharges the batteries. Unlike the power-split hybrid, its combustion engine only charges the batteries and never actually powers the car itself.

Many of the challenges that thwarted the EV1 are still in play. These cars will use advanced large ­lithiumâ''ion batteries, so battery life and safety remain serious concerns. And some new studies suggest that plug-in hybrids could pose significant pollution and resource problems of their own, largely depending on how the electricity to recharge them is generated.

As always, problems present opportunities, such as new roles for electrical engineers in power-train technology and in finding unconventional ways to support the modern auto’s power-intensive onboard electronics. EEs have already edged into mainstream auto design as regulations have called for the sophisticated electronic control of everything from combustion management to vehicle stability.

Silicon Valley has joined the fray. Bellwether Google has a project to convert hybrids to plug-in hybrids. Other Valley-based start-ups are making high- and low-end all-electric cars.

So perhaps the world’s car culture is now ready to head for greener car ­pastures, ­particularly if those ­pastures are filled with affordable, easy-to-use alternatives.

Both Toyota and GM plan to lay out their plug-in ­positions at the SAE 2008 World Congress, in Detroit, later this month (see For the auto ­industry, ­picking the winner is critical. Tens of billions of dollars, and ­perhaps even world ­automotive domination, are at stake.

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