Five Energy Innovations from the Detroit Auto Show

Energy innovations on display this week at the annual North American International Auto Show in Detroit are not the kind that scream "green." (Related Quiz: What You Don't Know About Cars and Fuel)

At the industry's biggest event for unveiling new models and concepts, energy is more of a background player this year. (See related, "Pictures: Cars That Fired Our Love-Hate Relationship With Fuel.")

Rather than incorporating flashy ideas for electric powertrains and alternative fuels, the new crop largely features tweaks to conventional gas models that will allow automakers to meet tougher fuel economy standards set to take effect between 2016 and 2025. (See related, "Pictures: A Rare Look Inside Carmakers' Drive for 55 MPG.")

Shedding Pounds for a More Efficient Pickup

For the 2015 model year of its top selling F-150 pickup, Ford Motor is using an aluminum body and bed to shed as much as 700 pounds (317.5 kilograms) from the truck's weight. The move has a domino effect, enabling use of a smaller, more efficient engine that features start-stop technology, which shuts the engine off when the truck comes to a stop (unless it's towing or in four-wheel drive) and restarts it within milliseconds. The new F-150 is expected to deliver the highest mpg for a full-size pickup truck when it rolls out later this year.

VW's Gas-Sipping Sedan

Volkswagen's new Passat BlueMotion Concept showcases a system for deactivating two out of four engine cylinders when the extra power isn't needed. Combined with start-stop technology, a coasting mode, and other efficiency improvements, the company estimates this will enable the gasoline-powered car to achieve up to 42 miles per gallon (17.86 kilometers per liter) in highway driving—if it makes it to production. Like all "concept" cars, it is here to showcase technological possibilities that have not yet been readied for mass market manufacturing. Although many features and ideas presented in concept vehicles eventually make it into real-world cars, the total package typically changes along the way.

Audi Allroad Shooting Brake Concept

This new concept for a plug-in hybrid "shooting brake," or small hatchback, combines a gasoline engine with two electric motors and an 8.8-kilowatt-hour lithium-ion battery pack within a lightweight body made of aluminum and carbon-fiber reinforced plastic. Audi says the design—meant to offer "very concrete glimpses of the near future"—could achieve fuel efficiency equivalent to nearly 124 miles per gallon and power up to 31 miles (50 kilometers) of all-electric driving on a single charge, plus several hundred miles using the gas engine. For comparison, that would be nearly 30 percent more fuel efficient than the 2013 plug-in hybrid Chevy Volt from General Motors, which is officially rated at 98 miles per gallon equivalent, with an estimated 38 miles of electric driving range and a total range of 380 miles. (See related, "Range Anxiety: Fact or Fiction?")

An Electric Car for (Some of) the Masses

The big announcement from electric carmaker Tesla Motors this year in Detroit had to do with numbers: 6,900 Model S premium electric sedans delivered in the fourth quarter of 2013—about 20 percent more than expected. (See related, "Tesla Motors' Success Gives Electric Car Market a Charge.") A long-promised electric crossover with a more affordable price tag, dubbed the Model X, was nowhere to be seen, but Tesla sales vice president Jerome Guillen told reporters the company is working on the next-generation model "feverishly" and expects to move it into production by the end of the year.  (See related, "Pictures: Eleven Electric Cars Charge Ahead, Amid Obstacles.")

And there was another important number from Tesla this week: 29,000. That's how many adapters the company has recalled after identifying a possible defect that can cause overheating and fire during charging of the 2013 Tesla Model S. (See related, "Tesla Model S Owner's Garage Blaze: A Fire Expert Weighs In.") In addition to issuing a replacement adapter plug, the company has updated Model S software over the air to fix the problem. (See related, "While U.S. Probes Tesla, What You Should Know About Car Fires.")

A Truck With Solar Out Back

Via Motors, based in Orem, Utah, takes the bones of conventional General Motors pickup trucks and outfits them with electric guts. In Detroit, the company is showing off a truck converted to operate as a plug-in hybrid, with a slab of photovoltaic solar panels covering the cargo bed. The panels could capture enough energy from the sun, Via executives say to add up to ten miles (16 kilometers) to the 40 miles (64.37 kilometers) of electric range that the company has demonstrated in prototypes. (See related, "Driving the Limit: Wealthy Nations Maxed Out on Travel?")

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This story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge.