Today, we look at plug-in electric car sales for May, drive the 2015 BMW 740Ld xDrive diesel sedan, and consider the future of ultracapacitors in cars. All this and more on Green Car Reports.

Ultracapacitors have been the "next big thing" in energy storage for well over a decade, but are carmakers finally getting on board?

A limited version of the 2016 Chevrolet Volt online configurator is live, and Chevy is taking orders for the car in California.

See why some researchers believe artificial photosynthesis could one day supply the world with renewable liquid fuel.

Mercedes-Benz will follow Tesla and sell its own batteries for energy storage, a new report says.

Plug-in electric car sales figures for May show several models surging.

The diesel-powered 2015 BMW 740Ld xDrive is one of the better choices for a long road trip.

The 2016 Subaru Legacy and Outback get a handful of upgrades, including the latest version of Subaru's EyeSight safety system.

Finally, the 2017 Audi A4 is spotted in a spy video. It's rumored to be the first model to get Audi's new electric all-wheel drive system.

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