In an attempt to appease Iowa corn farmers, the sometime-frontrunner mires himself in controversy.

Tree-friendly book lovers rejoice by planting trees for each book read.

Kenaf, the carbon-sequestering monster plant, provides food, shelter and carbon credits.

Carbon offsets could work in Indonesia, "clean coal" is a fantasy, beer companies are going greener, and can car factories really be local?

Private brokerage service Ecostreamjet purchases carbon credits to offset emissions generated by each flight.

Travel company cancels offset program citing its inability to reduce global emissions.

Matt Hickman unravels the mysteries behind offsetting CO2 and buying RECs. (Hint: One of them can fund tree-planting efforts.)

Olivine is a miracle green rock that absorbs carbon dioxide naturally from the air.

Officially called the "3D fast bus," the bus will literally straddle the road and carry passengers over cars and under overpasses.

Video: When a 10-mile stretch of L.A.'s interstate 405 is closed this weekend, there will be only one way to get through the gridlock: Fly over it. Take a ride

If a celebrity endorsement gets kids using a phone app that prevents on-the-road texting, emailing and phone use, who am I to complain? But, for the record, Jus

A 10-mile stretch of Los Angeles' 405 Freeway — the most heavily trafficked road in the country — was completely shut down this weekend as part of a $1 bill

Apply to the 30-Day Electric Bike Challenge and you could be selected to receive an e-bike for a month in exchange for swearing off the use of your car.

Studies show that drivers older than 85 get into fatal accidents almost 4 times as often as teens do, and intersections are a problem.

We're driving fewer miles and more of us are going car-free, yet we're only scratching the surface of car-isn't-king culture.

Two new studies decipher who prefers which kind of car, revealing unexpected attitudes that challenge many assumptions.

Helsinki is experimenting with a plan to match people with rides, making cars unnecessary.

What is Uber anyway? Is it a taxi service or as it claims, a technology platform, or something else altogether?

You can now get a charge out of its new go-anywhere GoCharger.

Audi’s R8 e-tron sports car is finally a reality — with almost 300 miles on a charge.

The key question isn't why Tesla stock dipped below $200, but why GM and Ford are at $30 and $14.

The introduction of the 2015 Kia Soul EV brings the notion of a practical, affordable all-electric car closer to the driveway.

These guys aren't shy about taking on Tesla, but first they need to ramp up the factory for this 1,088-horsepower, 200 mph electric from Croatia.

Next week Tesla will announce new home and utility solutions — but do they pencil out?

Charge Across Town is cutting carbon emissions with mobile charging. Just respect the two-hour limit.

Running 2 groundbreaking companies at the same time, Musk succeeds by putting himself on the line more than anyone else, says author Ashlee Vance.

Local Motors uses tech, crowdsourcing and design contests to create tomorrow's autos today.

The rumor mill says an all-electric shortened Panamera could grace the show stage in Frankfurt, with 250 to 300 miles of range.

And no, we won't be able to use ringtones. (There will likely be standardized noises.)

Science Guy Bill Nye wants battery-powered stock car racers. But fans go for the noise.

Rimac's Concept One is a $936,000 supercar made in Croatia, and only 8 will be built.

BMW Vision Next 100

The deal with the Tesla Model 3: 215 miles of range, zero to 60 under 6 seconds, $35,000 — but read the fine print.

Millennials and lower-income consumers are in a buying mood. They think that brand matters, and Tesla is the ultimate brand.

A ban on gas and diesel cars is the latest in Paris Mayor Anne Hidalgo's ongoing crackdown on air pollution.

Video: Pizza Fusion shows us how any job can become a green job with the right attitude and practices.

Greeting people you pass on the street with a smile and "Hello" is good for you and them.

More than one-third of adults in the U.S. over 45 likely suffer from chronic loneliness, but creative housing solutions like these can change those numbers.

Air conditioners have made architects lazy, and we've forgotten how to design houses that might work without it.

Why not design our homes so that we can get at the things that need to be changed? That's the idea behind "Open Building".

SwimCity is a housing concept for young Swedes who don't mind donning goggles or hopping in a canoe as part of their commute.

Just ask Jenna and Guillaume, who quit their 9-to-5 jobs to pursue their dream of touring North America in a custom-built tiny house.

Architect William Maclay brings some sense and sensibility to the concept of net zero energy building.

Bjarke attack! The Danish maverick is the subject of a climate-themed retrospective at the National Building Museum.

Sky City was supposed to be 220 stories and this building was supposed to be 97 stories; but there's more to building than just technical innovation.

Photographer Richard Silver captures the surreal ambience of the "blue hour" with these beautifully spliced landscape images.

A tour of the Bullitt Center in Seattle confirms that it's as green as it can be.

With the Living Building Challenge now under its belt, the facility is being heralded as one of the greenest buildings in the world.

The after-school carpentry wizards at Sawhorse Revolution have big, community-bettering plans for micro-housing.

Michael Green, champion of lanky, carbon-neutral buildings, sets his sights on the City of Light.