The auto industry’s race for cars that use less petroleum and spew fewer emissions has multiple technology pathways. Major global automakers are now aligning into one of two camps. The “Either/Or” carmakers choose one technology and run with it, while the “Portfolio” guys market multiple technologies all at once.

Mercedes-Benz is the most vocal of the portfolio companies. “If automakers are to be truly successful in reducing emissions, we can’t offer a one-size-fits all-solution,” said Sascha Simon, department manager of advanced product planning for MB USA, speaking at last week’s Wired’s “Energy + The City” conference.

Mercedes-Benz offers four BlueTEC clean diesel vehicles, including a sedan, wagon, and two SUVs. The company just launched its first hybrid, the S400 mild hybrid using lithium ion batteries. And Mercedes plans to introduce its first US fuel cell vehicles next year, with electric vehicles not far behind. “Many automakers are making clean vehicles an either/or proposition,” Simon explained. “We must offer a variety of vehicles that take into account different driving environments and different consumer comfort levels in adopting new technology.”

Nissan-Renault, is the strongest player in the “either-or” camp—making a bold and decisive move to lead the market for pure electric cars. In an interview in the current edition of Automotive News, Carlos Ghosn, CEO, said, “We are not intending to play a leadership role in hybrids. Anyway, it’s already taken. One company has already assumed leadership [referring to Toyota]. We want leadership on EVs.”

Ghosn said that it doesn’t matter who is the first to offer a particular technology. It’s about volume. Nissan plans to ramp up production of the all-electric Nissan Leaf to 200,000 units by 2012. “What’s going to be important is mass marketing it, and who’s going to be in control of all the core technologies leading to it.”

Choose Your Weapon, To Fight Global Warming

Most major global automakers dabble in a range of technologies, but when it comes to mass marketing in the US, they’ve made their move.

  • Toyota has hybrids, with the goal of introducing a gas-electric version of all its popular vehicles. Plug-in models will follow, but very slowly.
  • Volkswagen is clearly taking the clean diesel route, with the Jetta TDI currently leading the way.
  • General Motors is laser-focused on the Chevy Volt—with other plug-in series hybrids that might follow. GM has had mild and co-called “two-mode” hybrids for a few years, but they’ve remained low-production vehicles.
  • Ford is a “portfolio” player, with an emphasis on the full spectrum of electric drive vehicles, ranging from conventional hybrids, to plug-in hybrids, to pure battery electric cars. At the same time, it’s using its “Ecoboost” technologies—direct injection and turbocharging—to improve the efficiency of gas-powered cars.
  • Honda is harder to figure out, but will likely to take a portfolio approach, with an emphasis on smaller affordable hybrids, like the current Honda Insight and forthcoming CR-Z and Fit hybrids. The company considered a clean diesel Accord, but indefinitely delayed the effort. Its Honda Civic GX is produced in limited numbers, and the Honda FCX Clarity fuel cell car is even more limited.

Emissions and energy are no longer pet projects for these carmakers. Choosing one, or multiple, green technologies is no longer strictly a decision for the R&D department. It’s become a key way that automakers establish their brand in a competitive marketplace.