Today, we look at why Volkswagen cheated on diesel emissions tests, what the U.S. Environmental Protection Agency (EPA) may be doing to prevent future cheating, and whether it's worth buying an extended warranty for a Tesla Model S electric car. All this and more on Green Car Reports.

We're getting a better idea of the scope of the Volkswagen diesel emissions scandal as the days go by, but why did VW cheat on emissions with its TDI models in the first place?

Which is the best use of electric cars: eliminating gasoline, or saving lots of it? Those two goals are not the same, according to new analysis.

See how Volkswagen drivers are reacting to the revelation that the company cheated on emissions testing.

In the wake of the VW emissions scandal, the EPA will add on-road testing to the current laboratory-based emissions regimen, a top official says.

HyperSolar claims it has reached the voltage necessary to produce hydrogen from solar energy on a commercial scale.

Hear what a Tesla Model S owner has to say about buying an extended warranty for the electric car.

Separate recalls of the Hyundai Sonata and Accent affect nearly 570,000 vehicles in the U.S.

Finally, see the Tesla Model X electric crossover's "falcon" doors in action. Tesla will deliver the first Model X crossovers to customers tomorrow.


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