Transcript for Tesla CEO Elon Musk's Plan to Save the World

Every year, we look at innovators we think belong on this list. Usually, they fall under the category of "Technology." There were a lot of choices this year -- apps like tinder, the iPhone 6, and others. We decided to go electric. Elon musk grew up Reading Isaac asimov novels about space travel. And now he's trying to take the fiction out of science fiction. Elon musk has a plan to save the world. Step one -- he is going to roll back global warming by getting rid of gasoline-powered cars. Step two -- he's going to use his rockets to colonize Mars so he can escape Earth if a comet strikes us, or if step one doesn't work. Step three -- he's going to accelerate travel to nearly the speed of sound with vacuum tubes, using technology similar to "The jetsons." What a way to end a day. Walters: For ordinary mortals, that would be impossible, but not for elon musk. Elon is an entrepreneur and inventor and billionaire. He is the C.E.O. And driving force behind two of the most innovative companies in America -- tesla, which manufactures cars that are 100% electric, and spacex, which builds reusable rockets that carry cargo and humans to the international space station. Using tesla and spacex, elon musk is going to bring us into the future. He was born in South Africa in 1971. His mother was a model and his father an engineer. Elon taught himself computer programming by age 10. By 12, he had sold his first video game, "Blastar." After college in the U.S., he founded zip2, a kind of online yellow pages. At 28, he sold it for $307 million. He took that money and created paypal, the company that allows people to pay for things online. Then he sold paypal for $1.5 billion. At that point, elon had to decide what to do with his share of the money. The easiest thing for me to have done after paypal would have been to start a new internet company. Instead, what elon did was to invest in the electric car and in space travel. Almost all people regarded it as stupid or insane or both. Along the way, he married this beautiful woman and had five sons with her, then got divorced, and married thisbeautiful woman, then got divorced, then went back to dating thisbeautiful woman. Yes, that's ex-wife number two. His goal for tesla was a car that could revolutionize automobiles. The car would have no engine, run on batteries, and be able to go long distances on a single charge. There were some challenges. He had to re-think the way we made batteries because the battery had to last a long time. So he created a really big battery, which took up the entire bottom of the car. That's a really bigbattery. Then he had to invent a charger for the battery. Doing all that meant the car cost over $100,000. Meanwhile, in space, elon also faced challenges. He wanted to build a rocket that could be used for return trips, instead of burning up on its return to Earth, so that he could eventually colonize Mars. He kept launching rockets, but they kept failing. By 2008, spacex was running out of money. So was tesla. Then the global economic crisis hit. With both companies and his entire fortune on the line, elon launched one final rocket. Woman: ...Three, two, one, zero. We have lift-off! Walters: It worked! Woman: The falcon has cleared the tower. Walters: Nasa gave him a $1.62 billion contract. Since then, he's created the technology to make the rocket go up and down. And he's planning a trip to space himself in a few years. There is now a tesla that can accelerate from zero to 60 miles per hour in 3.2 seconds. Musk: In the option selection, you'll be able to choose three settings, which is Normal, sport, and insane. It will actually say "Insane." Walters: You can buy a tesla now for around $75,000, and the price is coming down. It has been rated the safest car ever made. It's even won "Best car" awards. Plus, you can run it forever, using free charging stations powered by the sun. Every day, elon musk is a little bit closer to saving the planet. And if you're wondering about the vacuum tubes, well, there's always tomorrow.

This transcript has been automatically generated and may not be 100% accurate.