There's an emerging rivalry between two different technologies for zero-emission transportation: battery-electric cars and hydrogen fuel-cell vehicles.
Within the auto industry, each powertrain has its strong advocates. Some carmakers are focusing on either fuel cells or batteries, to the exclusion of the other.
Hydrogen fuel cells are backed most notably by Toyota and Honda, while Tesla, Nissan, Chevrolet, and Renault are best-known for electric cars.
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Mercedes-Benz parent Daimler isn't one of the companies that's chosen one over the other; it plans to sell both fuel-cell and battery-electric cars.
But that doesn't mean its leaders think both powertrains have equally good prospects.
Battery-electric cars are "more likely" to become dominant, Daimler CEO Dieter Zetsche said in a recent interview with German newspaper Euro am Sonntag, quoted by Engadget.
Mercedes-Benz B-Class F-Cell
Daimler isn't counting fuel cells out, Zetsche explained, but right now it seems the obstacles to large-scale electric-car adoption can be more easily overcome.
He said longer ranges and fast charging for battery-powered cars are "within reach."
But it is less clear how fuel-cell cars can be made more affordable, or how hydrogen fueling infrastructure can be made widely available, he believes.
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In the U.S., Daimler currently offers the Mercedes-Benz B250e (nee B-Class Electric Drive) in a limited number of states, as well as the Smart Fortwo Electric Drive.
It's also expected to launch at least one mass-market electric car in the next few years.
This could be a mid-size sedan or crossover aimed at the Tesla Model S or Model X, or possibly a smaller crossover based on the recently-introduced GLC-Class.
Smart Fortwo Electric Drive and Mercedes-Benz B-Class Electric Drive at driving school.
The GLC-Class platform will also reportedly spawn a production fuel-cell model.
Rumored to be called GLC F-Cell, it's expected to debut next year.
Zetsche is heavily weighing the relative merits of powertrain technologies, because he apparently doesn't expect much support from governments.
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He applauded Germany's goal of putting 1 million plug-in electric cars on its roads by 2020, but didn't show much confidence in the subsidies that have been key to electric-car adoption in other countries.
The Daimler chief dismissed subsidies as a "bridging function" that could only lead to short-term sales increases.
That may be just as well, as even after many public discussions the German government hasn't approved yet any electric-car incentive programs.