[OBAMA, MARCH 30] In fact, the Air Force is aiming to get half of its domestic jet fuel from alternative sources by 2016. And I'm directing the Navy and the Department of Energy and Agriculture to work with the private sector to create advanced biofuels that can power not just fighter jets, but also trucks and commercial airliners.

[ASSURAS] We're going to be looking at biofuels and planes, trains, and automobiles throughout the show, including a rare interview with Transportation Secretary Ray LaHood. But we start in the sky, as Josh Zepps takes a look at the future of flight in this "energyNOW!" Spotlight.

[ZEPPS] If we you need a zero-carbon-emission car or boat, or train... that ain't rocket science -- you just find an alternative fuel. But if you need a source of energy so concentrated that it can blast a one-million- pound aircraft into the sky, then... well, frankly, that is rocket science. For the future of aviation, I think I'm in the right place.

The world is on the brink of an aviation revolution. Within the next few years, you'll be flying on planes that are radically more efficient than ever before, in ways you notice and in ways you don't. The ultimate goal is a commercially viable passenger plane with a carbon footprint of zero. To learn about the energy-efficient planes of the future, I headed to NASA's Langley Air and Space Research Center in Virginia...

I think NASA could use some bigger doors.

...and tracked down Fay Collier, head of the Environmentally Responsible Aviation unit.

[COLLIER] In terms of aircraft efficiency, you want to look at three things. Essentially, you want to look at weight reduction. You want to look at drag reduction. And you want to look at improving the propulsive efficiency of the power plant, the propulsion system.

[ZEPPS] In other words, planes that are light, sleek, and powerful. The best way to make them light is to ditch all that metal. Despite endless production delays, Boeing's new 787 Dreamliner should soon be the first aircraft not made out of metal since... well, since planes were things you didn't much want to fly in, anyway. The 787 is made out of carbon fiber composite material. Basically, it's 80% plastic. And the technology is moving so fast that already NASA has an even newer composite that's 10% lighter than the 787's and 25% to 30% lighter than aluminum. They call it PRSEUS.

[COLLIER] PRSEUS stands for "Pultruded rod stitched efficient unitized structure."

[ZEPPS] Protruded rod?

[COLLIER] Pultruded -- P-u-l-truded.

[ZEPPS] Pultruded rod stitched efficient structure.

[COLLIER] Unitized structure.

[ZEPPS] That's what I said, unitized structure.

Well, whatever you want to call it, it's one of the world's most advanced materials.

One thing that strikes me about this is, not only is it very, very light -- it's extremely thin. Is this the thickness of the fuselage of the plane?

[COLLIER] Absolutely. It's almost like blue-jean material. This rod, that's the same rod that you use in your tents. That's what this material is here. So it's a solid, and this other stuff is more like a piece of cloth.

[ZEPPS] A very, very tough piece of cloth.

[COLLIER] Yes, exactly.

[ZEPPS] A piece of cloth so tough, in fact, they've already made a plane out of it. This is the prototype X-48B. As you can see, it's not just lighter than existing passenger planes; it's a whole lot sleeker, too.

[COLLIER] The difference between the tube and wing and hybrid wing body is the blending of the fuselage and the wings. And we get a much better, more efficient shape in doing so because of the way the lift is distributed across the aircraft.

[ZEPPS] It may herald a generation of passenger aircraft that are no longer built by bolting a couple of wings to a tube, but by using the whole surface of the aircraft as one giant "wing thing." More lift means you need less fuel to lift it.

[MAN] All right, let's stop the blade.

[ZEPPS] NASA invited me to witness these aerodynamic advantages firsthand at a live wind tunnel test.

[MAN] Taking data, point 800.

[MAN] 799 is the point break.

[ZEPPS] I have no idea what they're talking about.

You don't need to be a rocket scientist to see that huge strides are being made, but if the ultimate goal is a climate-friendly plane and oil is still the only energy source with the punch to get us airborne, then even the most efficient planes will still be carbon-spewing villains, right? Not necessarily.

So this little seed has in it...

[BULZAN] Oil.

[ZEPPS] The makings of jet fuel.

[BULZAN] That's right.

[ZEPPS] Incredible.

At the Green Lab facility at NASA Glenn in Cleveland, Ohio, Dan Bulzan is producing plants that could produce the fuel for the lighter, sleeker planes of the future.

[BULZAN] What we're trying to do here is improve the oil content of the plants themselves. We're hoping to produce oil that's a little more suitable for the processing into jet fuel. This is a salicornia. It's very salt-tolerant. And you can see it's grown in kind of a sand medium.

[ZEPPS] So it's a sort of marshy kind of plant?

[BULZAN] Yeah, it grows in coastal areas, areas where other -- food crops would not grow.

[ZEPPS] That is important. Algae and halophytes, or saltwater plants, can be planted along coastlines, or even offshore. Biofuels derived from crops, from farmland, where there would have been plants anyway, don't suck up any extra carbon at all. These plants do.

When I think about the life cycle of the fuel that we currently use in aviation, hundreds of millions of years ago, animals died. They then got compressed into oil, into fossil fuels, which we then drill out of the ground and we use for one time only, burning it in aviation. Here, I'm feeding seaweed to fish who will poo it out to feed plants from which we'll extract oil, which we'll then burn in aviation fuel. So really, we could be powering planes on seaweed. Is that fair to say?

[BULZAN] You could say that.

[ZEPPS] NASA is keen to emphasize that it is early days and a lot of research still needs to be done. But biofuels have fans in high places. Like Bill Glover, Vice President of Environmental and Aviation Policy at Boeing.

[GLOVER] We have proven, over the last three years or so, that that's not only feasible, it is absolutely doable. And it gives us as good or even better fuel, because now we design in the characteristics that we want rather than just deriving the characteristics from what's in a barrel of petroleum.

[ZEPPS] Lifting hundreds of millions of gallons of gas 34,000 feet into the air every day is not cheap. According to the Air Transport Association, the expected fuel bill for global commercial aviation this year alone will be a whopping $39 billion.

[GLOVER] Fuel efficiency, CO2 efficiency is really in the DNA of every product that we make.

[BULZAN] I don't know when it will be, but I don't see any reason why we couldn't have a totally green aircraft, at some point in the future.

[TEXT ON SCREEN] To learn more about NASA's renewable fuels project, go to energyNOW.com.

[ZEPPS] When that day comes -- thanks to lighter materials, more aerodynamic designs, and cleaner propulsion -- let's just hope that airlines have also found a way to bring back in-flight pillows. At NASA Glenn in Cleveland, Ohio, Josh Zepps, "energyNOW!"

[ASSURAS] I don't know about you, but I sure miss those pillows. By the way, the Federal Aviation Administration has its radar set on energy savings and lower emissions by focusing on more direct landings and flight paths. It's looking at NextGen. That's a system that uses satellite rather than radar navigation. Satellites will allow controllers to plot direct flight paths and to eliminate inefficient landing approaches -- you know, that circling the airport until the plane can land. The FAA estimates it could save 1.4 billion gallons of aviation fuel and cut 14 million tons of CO2 through 2018 by using NextGen.

So, just how much CO2 goes into the air when you fly? Let's find out. We're using the carbon dioxide emissions calculator from the International Civil Aviation Organization. So, let's say you fly once a month from Washington's Reagan National Airport to Los Angeles, about 4,600 miles round trip. That equals more than 8.5 tons of carbon dioxide a year. Add that up -- 12 flights emit about the same carbon as one year's worth of electricity used in the average home.