>> NARRATOR: They power our lives... from cars to lawnmowers... from ships to steam trains. They've transformed our world, and taken us to the moon. Now, "Engines" on<i> Modern</i> <i> Marvels.</i> <font color="#FFFF00"> Captioning sponsored by</font> <font color="#FFFF00"> A&E TELEVISION NETWORKS</font> It's no accident that the root word of engine is "ingenious." For three centuries, these ingenious designs have been the ultimate expression of man's desire for technical excellence, and through many generations of technological progress, they've had a profound effect on the way people travel and work. Steam engines replaced the horse. Electric motors and gasoline engines replaced the steam engine. Then the jet engine and the rocket engine took things to a higher level And now, microtechnology engines are proving that less is more. This march through the centuries began when the steam engine ushered in the Industrial Revolution. It freed mankind from total dependence on primary sources of power, like wind, water and muscle. Steam engines would be used to power factory machinery, trains, ships, tractors and automobiles. >> PAUL RONNEY: Before steam, mostly we used animals as our mode of transportation. When steam came along, of course, we could move more material faster and more reliably than we could, of course, with animals, and so that was a big transformation. People became less tied to being in small cities. They could live out on the farm and still be connected, if you will, to the cities. >> NARRATOR: In a steam piston engine, steam enters one end of a cylinder and pushes a piston back. Then it enters the other end, pushing it the other way. The steam comes from a boiler, a metal water container that is heated, usually by burning fuels like wood, coal, oil or natural gas. A steam turbine engine is like a windmill, except that it's blades are propelled by hot steam under high pressure, instead of wind. To this day, steam turbines are widely used. In fact, they are used to generate most of our electricity. The Greek scientist Hero of Alexandria built the world's first steam engine about 2,000 years ago. It was, basically, just a round metal ball with two kettle-like spouts coming out of it. When steam was piped into the ball, it spun around. Hero put it on display at the Serapeum, a museum in Athens, where it entertained visitors for years, although it was never viewed as anything more than an interesting toy. In 1705, two British engineers, Thomas Savery and Thomas Newcomen, produced a large steam engine that could be used to pump water out of flooded coal mines. The engine used a piston, a rod- like device that moved back and forth inside a tubular enclosure called a cylinder. >> MERRITT ROE SMITH: These early engines didn't have the gearing that could convert reciprocal motion into circular, machine-driving motion. That didn't happen until the 1770s, when James Watt developed what is probably the most famous steam engine of the 18th century. >> NARRATOR: James Watt, a professor at the University of Glasgow, developed several improvements for the steam engine, making it much more practical to drive machinery. His "Flying Ball Governor" expanded as the engine went faster. Centrifugal force caused the heavy metal balls to spread out, and that closed a steam valve, which slowed the engine down. >> SMITH: And as it spread out, it would control the movement of steam into the cylinder, and that was a very efficient device. They keep it from revving out of control, but, more importantly, they keep it in a steady, regular, uniform motion. >> NARRATOR: By 1800, more than 1,500 steam engines were at work in Britain, Europe and the United States. In addition to pumping water out of mines, they were also powering factory machines. >> SMITH: Britain was the first nation in the West, in the world really to become industrialized, and so much of what was going on there was built around the advent of steam power. >> NARRATOR: By 1830, steamships were making regular crossings of on high seas the Atlantic. The earliest steamships didn't look that much different from the sailing ships of that period. They still had tall masts and sails, but the big difference was the large paddle wheel in the middle of the ship. Turned by a steam engine, it provided extra power for the ship, as it clawed its way through the water. >> SMITH: Both steamboats, then later railroads, you know, dramatically shortened the time that people could traverse long distances. The American politician, John C. Calhoun, often used the expression about "conquering space." And basically that's what these machines did was that they helped to conquer space. They shortened distances between two places. >> NARRATOR: That was particularly true of the steam piston engines riding the ribbons of steel that opened up the American West in the 1800s. In 1860, there were more than 30,000 miles of railroad tracks in the U.S., and, in 1869, the Golden Spike was driven at Promontory Point, Utah to unite the Union and Central tracks which ran from the east and west coasts. Most American trains at the time were pulled by so-called "4-4-0" steam engines, which had 4 lead wheels, and four driving wheels. They weighed about 50 tons. Another important application for the steam engine was in farm equipment. >> ROD GROENEWOLD: Whether you're burning straw in a field with an agricultural engine, whether you're burning wood, whether you're back East and you're burning coal, you know, the steam engine was very adaptable, and hungry for any fuel you could feed it. >> NARRATOR: And that made it ideal for farm use. Huge steam tractors began to transform agriculture in the late 1800s. >> GROENEWOLD: That was an era when terms like Behemoth, Leviathan, some of those terms were very commonly used. Some of these engines, you know, weighed up to 10, 20 tons-- huge! >> NARRATOR: In the mid-1800's an American, George Corliss, developed the most important new steam engine invention since James Watt. His new governor system allowed the engine to run more steadily, making it ideal for use in textile mills. This Corliss-designed engine, recently restored, was one of three installed at a sugar mill in Southern California in 1911. For the next 67 years, it powered machinery that refined sugar beets into sugar. >> GROENEWOLD: They had steam readily available to cook and clean the beets, power all the machinery. It powered a generator in that factory, so they had the lights and the power for everything else, and the motive power to run the centrifuge to run the sugar out of the beet pulp, so, you know, a very efficient system. That steam engine just did it all. >> NARRATOR: The huge flywheel weighs 19,000 pounds, and the entire engine weighs 90,000 pounds. The 300-horsepower engine was in service until 1978, when the Holly Sugar Mill in Santa Ana was torn down. A completely new kind of steam engine, one that had no pistons, was pioneered in the late 1800's by two engineers, Charles Parsons of Britain and Carl de Laval of Sweden, and it's the only type of steam engine that is still in wide use today. Steam turbines, which use steam pressure to turn fan-like blades on a rotor, are more compact than steam piston engines, and usually permit higher temperatures and greater steam expansion. That means more power. By the early 1900s, several steam turbine ocean liners were in Atlantic service. By 1920, the steam turbine had eliminated the older steam piston engines on major vessels. The great transatlantic liners, from the<i> Queen Mary,</i> launched in 1934, to the<i> United States,</i> launched in 1951, were all driven by steam turbines. Today, U.S. Navy aircraft carriers and submarines are powered by nuclear steam turbine plants. The TV you're watching right now is, in all likelihood, being powered by steam... since the majority of electric power plants in America use steam turbine engines, including nuclear plants like this one. >> RONNEY: The power plant engine is indeed a steam engine, whether again the heat source is a nuclear source or coal or natural gas, it is a steam engine. It's somewhat ironic that we still use technology that was invented almost 200 years ago. >> DAVID GARCHOW: The water circulates through the core, picks up the heat from the fission event, takes it to the steam generators, where it flashes to steam, goes out of the steam generator into the main steam pipes, into the main turbine where it turns the turbine to make electricity. >> NARRATOR: Steam turbines may be going strong, but steam piston engines have long been silent. They haven't been manufactured in the U.S. since the 1950s. But the sound of the steam piston is all around at the antique engine museum in Vista, California, near San Diego, where they have dozens of working steam engines. (<i> steam hissing rhythmically</i> ) In their day, they were impressive images of unprecedented power, but there were inherent flaws that turned these fire-breathing monsters into dinosaurs. >> RONNEY: Heat transfer is a slow process, and in the steam engine, one needs to transfer heat from a hot fluid, namely the combustion gases, to the working fluid that actually produces the power, namely steam, and people found that by using an internal combustion engine where the thing that does the expansion and the thing that generates the heat is one and the same material, namely the fuel/air mixture, that one could get much more power out of a given size engine. >> NARRATOR: But before the internal combustion engine came along, another new machine showed up to help power the world. It wasn't an engine, and it didn't burn fuel. Up next: The electric motor wins a place among the engines of the world. "Engines" will return on<i> Modern Marvels.</i> >> NARRATOR: We now return to "Engines' on<i> Modern Marvels.</i> When steam engines first came into widespread use in the early 1800s, they were extremely powerful, but that power came at a price. They were also extremely dangerous. To create maximum power, their boilers had to contain steam at high pressures, and they weren't always up to the task. >> SMITH: There were a lot of problems in the 19th century with the explosion of boilers. Before you know it, you'd have an explosion that could kill everyone. >> NARRATOR: Robert Stirling, a clergyman in Scotland in the early 1800s, was tired of seeing his parishioners getting injured or killed by exploding steam engines, so he decided to do something about it. >> BRENT VAN ARSDELL: Part inventor, part preacher, 100% renaissance man. He was an incredible guy. >> NARRATOR: Stirling came up with an entirely new engine design in 1816, which he called "a hot air engine." Today, it's known as the Stirling engine. >> VAN ARSDELL: The Stirling engines that he developed were low pressure engines and so there was nothing really in there that was high pressure that could explode, even if the machine failed. Stirling engines are engines that heat one side of the engine and cool the other side of the engine, and then there's a mechanism inside the engine that moves the air back and forth between the hot side and the cold side. When the air is on the hot side it expands and pushes up on a piston, and when the air's on a cold side, it contracts and pulls down on a piston. >> NARRATOR: But there was a problem with Reverend Stirling's invention-- the metals used in the 1800s were not heat resistant enough to make the Stirling engine as durable as a steam engine. >> VAN ARSDELL: The metals didn't stand up to the high temperature of continuous flame. The... boiler is the part of the steam engine that is exposed to continuous flame. In a Stirling engine, it's the hot cylinder of the engine, so it's a different part of the engine. >> NARRATOR: But with today's modern metallurgy, some believe the Stirling Engine may now be viable. Brent Van Arsdell manufactures small demonstration engines that show off the unique capabilities of Reverend Stirling's invention. One of the engines runs on the hot air from a cup of coffee. But surprisingly, it also runs on the cold air from a bowl of ice. All it needs is a temperature difference to make it run. >> VAN ARSDELL: All you've got to do is keep one side hot and the other side cold. You can do that any place that you can keep the temperature difference and these things will run. >> NARRATOR: This Stirling engine can run on the heat from the palm of your hand. >> JOHN HEYWOOD: Now over the decades, people have tried to put Stirling engines in vehicles, and the conclusion right now is, no, it's an expensive engine, much more expensive than the sort of alternative, like gasoline, diesel engines, and it's very hard to make it efficient on a vehicle, because the way the engine is running changes all the time. As you and I drive, we speed up, we slow down, we accelerate. That makes it hard for the engine to stay efficient all the time, and especially hard for the Stirling engine. >> NARRATOR: The steam engines and Stirling engines of the 1800s soon had a new competitor to help power the machinery of the Industrial Revolution. And today, that new competitor is still with us. We don't have steam engines in our houses, but we do have lots of electric motors. Look around your house. It's loaded with them-- electric clocks, air conditioners, CD players, VCRs, fans, vacuum cleaners, blenders, and of course, who could forget the electric toothbrush? They are all powered by electric motors. >> BOB PALMBACK: Without it, we wouldn't even be able to sit here and make this interview. It wouldn't be worth getting out of bed, unless you wanted to be back in the horse and buggy days. >> NARRATOR: Unlike most engines, which use some kind of combustion to create heat, the electric motor is powered by an entirely different principle. It's based on the fact that when electricity flows through a wire, an electromagnetic field is created, which means you've temporarily turned that wire into a magnet. Turn the electricity off, it's not a magnet anymore. Hook it up the opposite way and its north and south poles reverse. An electric motor does this over and over, using the magnetic force to create motion. >> PALMBACK: What it does is creates a magnetic field and it actually drives it, just like Doug and I are doing. As the power's going through this field, this is a magnetic field and it's revolving around here and it's sucking this around. >> NARRATOR: Of course, electric motors need electricity. So their history begins with the earliest electrical experimenters. In 1824, Michael Faraday patented his Direct Current or DC motor. In 1888, the eccentric genius Nikola Tesla patented his Alternating Current or AC motor. Today, we use both. If it runs on batteries, it's a DC motor. If it plugs into the wall, it's an AC motor. >> FREDERICK DESANTI: Tesla was the first one who introduced the concept of alternating current, where you would change the polarity back and forth 60 times or 50 times a second, as it was, and Edison didn't believe in that, and Edison actually fired Tesla and he went to work for George Westinghouse. Tesla was right. Alternating current could be transmitted over miles and miles, and there were significant limitations for direct current transmission distribution systems. >> NARRATOR: George Westinghouse acquired the patents for Tesla's alternating current system and, in 1891, installed the first world's first high-voltage AC transmission line in California, connecting San Antonio Canyon with Pomona and San Bernardino. In 1894, Westinghouse began manufacturing another one of Tesla's inventions, the AC motor. Early electric motors were used to power some of the very first cars, along with steam engines and internal combustion engines, which used an ignited fuel, like gasoline, to propel a piston up and down. >> SMITH: I don't think anyone knew, you know, at least for the first decade or more of the automobile's existence, as to who was going to win out. >> NARRATOR: Around 1912, the internal combustion engine finally did win, ironically, because of the addition of an electric motor. It was called "the starter." And it did just that-- getting the pistons to start firing, without throwing the driver's back out or worse. >> SMITH: Up until that time, you had to crank an engine to get it started, and it was not only difficult, but was dangerous. It could really break bones in your arm. If one of those things jerked back on you, you could really hurt yourself, but with the electric starter, that changed the whole ball game, and immediately signaled the demise of both the electric automobile, and the steam-powered automobile. >> NARRATOR: Like the hand crank, the starter's electric motor initiated the compression and combustion cycles necessary for the engine to run on its own. Some of the largest electric motors have been made for use in elevators. In 1933, Westinghouse built the world's fastest elevators for New York's Rockefeller Center. In 1972, Westinghouse installed the elevators in what was then the world's tallest building-- the Sears Tower in Chicago. In the 1990s, the electric motor made an automotive comeback when General Motors introduced the "EV-1." It was extremely lightweight, with a strong, rigid frame, and one of the most aerodynamic car bodies ever made. Some said it was built more like an airplane than a car, but the highly-advanced EV-1 was a flop, and GM canceled production in 2000. As with all electric cars, its biggest problem was limited range between battery charges. >> PALMBACK: If you're in a hurry to go someplace, and you can only get 100 miles and have to stop eight hours to charge, I mean, you might as well have a covered wagon. >> HEYWOOD: I think it's unlikely that in the next ten, 20 years, electric vehicles will compete with standard cars. Battery technology is just not good enough, and these batteries are expensive once you take them up to the scale that you need to store enough energy to drive a vehicle. Now if they get a bit smaller, and we're willing to have a limited range, it might be that electric vehicles will be interesting, because they really would have no emissions where the car is being driven. >> NARRATOR: Electric cars may not pollute where they're driven, but there's still pollution where the electricity is generated to charge their batteries, since most of it comes from power stations that burn fossil fuels. Because electric vehicles require either batteries with limited range, or overhead power lines they can hook onto, they've been more popular for public, rather than private transportation. Cities like Los Angeles got their first electric trolley buses in the early 1900s, and some cities still have them. Virtually all subway systems and light rapid transit systems use electric motors. And just why do we call them electric "motors" when we call the other machines that power our lives "engines"? Well, that's a matter of debate, and it's a debate that can keep scientists and engineers amused for hours. They sometimes refer to it as "the great engines-versus-motors debate." >> HEYWOOD: Um, I don't think there's a clear answer. Technically, we use the word engine for a device that takes energy from some source, like fuel, and converts it into power that we can use to drive something. >> RONNEY: Engines versus motors. In my personal opinion, I think that an engine, when I think of engines, I think of heat engines. I'm a thermodynamacist, and we talk about heat engines. >> HERMANCE: There are many inconsistencies, even within the industry, with regard to nomenclature. >> RONNEY: The things that I would call motors, as opposed to engines, would be primarily things like electric motors. >> NARRATOR: And how do you explain "outboard motors," which almost always have engines in them? >> HERMANCE: Very good question. That... I never said we were consistent in how we use those words. In the automotive industry, a motor is an electrical machine, an engine is an internal combustion machine. >> NARRATOR: Then how did Detroit get to be Motor City? (<i> laughing</i> ) >> HERMANCE: Another very good question. >> NARRATOR: Up next: The internal combustion engine creates a new industry in Motown, and the world goes mad for motoring. "Engines" will return on<i> Modern Marvels.</i> >> NARRATOR: We now return to "Engines" on<i> Modern Marvels.</i> At rush hour in a city like Los Angeles, it's painfully obvious how the internal combustion engine changed the world. Next time you're caught in a mess like this, thank Etienne Lenoir. He developed the first internal combustion engine back in 1860. Like the very first steam engines, it was developed for pumping water out of coal mines. It was a big success, and about 5,000 of the engines were sold. 16 years later, in 1876, Nikolaus Otto patented the first four-stroke version of the internal combustion engine. Otto's four-stroke system is used in nearly all of our cars today, so it's fitting that we call it "the otto industry." >> HEYWOOD: We're still using that same four stroke cycle, and roughly our arrangement, we've got a piston and a cylinder, we've got a connecting rod, and we've got a crank as our simple mechanism for converting the up and down piston motion to rotation of a drive shaft. That's what he came up with and we're still using that today, 150 years later. >> NARRATOR: In 1892, Rudolph Diesel patented the Diesel engine. >> Note the absence of a sparkplug. >> NARRATOR: It's similar to the regular internal combustion engine, except that it has no spark plugs. Air is sucked into the cylinder on the downstroke. Then it's compressed on the upstroke, which makes the air extremely hot-- so hot, that when oil is injected, the fuel/air mixture ignites. Mercedes Benz made the first production diesel automobiles in the 1930s. Because of their brute power and ruggedness, diesel engines made by various manufacturers are widely used in large trucks and heavy equipment. As both gasoline and diesel engines evolved, they changed the way cities were built. They also changed the way wars were fought. In World War II, U.S. engine production reached an all-time high, as new engines made in Detroit powered the war effort. American auto manufacturers used their production machinery and know-how to build four million engines of all types and sizes-- for trucks, tanks and aircraft. This mile-long factory outside of Dearborn, Michigan, cost the government $65 million to build. Under Henry Ford's management, it turned out 57,000 aircraft engines and 9,000 bombers. Ford's other plants produced a quarter of a million tanks and jeeps. >> HEYWOOD: Since we were relying on piston-engine aircraft for our fighters and bombers, the automobile industry converted its engine production facilities to producing engines for these applications, and the new car production went down to very low numbers. >> NARRATOR: Up until the 1950s, most engine development concentrated on making engines more powerful and cheaper to build. Then, this appeared on the horizon. It's called smog. And because of it, engine technology had to accelerate in a different direction. Pollution control systems introduced by all auto manufactures in the '60s and '70s reduced emissions, but they also sapped power, since they had the effect of reducing air intake. An engine that can't breathe freely produces less power. In the life of the internal combustion engine, most developments have been evolutionary, but one of them... was revolutionary. German inventor Felix Wankel came up with a radically new and simple design for an internal combustion engine way back in 1924, but it wasn't until 1957 that he built the first truly functional Wankel rotary engine. It was a dramatic departure from the piston engine, and because it spun around, instead of pumping up and down like pistons, the rotary engine dramatically reduced vibration. >> HEYWOOD: Many, many people over time have tried to think of a better geometry. There are some negatives to this simple piston-connecting-rod- cylinder arrangement. Masses move up and down, and that's hard to prevent that causing vibration, but, so far, with the one exception of the Wankel, nobody's invented a geometry that's got into "real world" production. This roughly triangular-shaped rotor sort of moves around inside a container, but not quite symmetrically, it's off center, and so, as it rotates, this triangular rotor, it creates sort of smaller volumes and larger volumes, in a similar way to the piston moving up and down in a standard engine cylinder. >> KOBY KOBAYAKOWA: I have a very strong attachment to the rotary engine, without any questions. >> NARRATOR: "Koby" Kobayakawa, recently retired, was project director for Mazda's highly successful RX-7 rotary-engine sports car. >> KOBAYAKOWA: This is the only moving part of the rotary engine, and we don't have any intake or exhaust valve or cam shaft. Basically, we have only two moving parts two, two rotors. In the case of a V6 engine, the moving parts like pistons and connecting rod and valves and cam shaft may be 50 moving parts. >> NARRATOR: In 2001, Mazda completed development of an all- new rotary-engine model called the RX-8. It may look small, but the 255- horsepower engine is competitive with much larger piston engines. And it's still the only car engine in mass production that has no pistons. Koby Kobayakawa talked to Felix Wankel just a few years before the inventor's death in 1988. >> KOBAYAKOWA: I had been admiring him so many years. His eye to look into Mazda rotary engine is always more like a father's eye when looking at the children. He's so nice and he was very, very pleased with Mazda's effort and result about the rotary engine. >> NARRATOR: Felix Wankel would be proud that the radical idea he came up with in 1924 spins on. Up next: tiny engines that make a dust mite look like a monster. It's called microtechnology, and it's the next "small" thing in engines and motors. "Engines" will return on<i> Modern Marvels.</i> >> NARRATOR: We now return to "Engines" on<i> Modern Marvels.</i> 1941... the world was at war, and it was time for the next new engine technology to change the world. Enter the jet. >> HEYWOOD: A jet engine is a gas turbine where you throw the exhaust gases fast out the back end to provide thrust, and the compressor and turbine of the gas turbine do the compressing to give you the high flow you need to throw out, and the turbine provides the work to drive the compressor, and what's left is what you use for thrust. >> RONNEY: Imagine if you're baking cookies. Imagine if you baked the cookies one at a time, you put some dough on a tray, you shove it into the oven, you wait for it to bake, and then you pull it out. That's what we do in the internal combustion engine with the reciprocating piston. We put the fuel/air mixture in, stop. We compress it, stop. Burn it, expand it, stop. Push it out, stop. It's constantly stop start, stop start. Whereas, with the jet engine, it's basically like a continuous process. Imagine putting all your cookie dough on a conveyor belt and running it through an oven. >> NARRATOR: It all started about 60 years ago, when Britain and Germany were racing to develop the first-ever jet aircraft. In 1941, Germany was the first into the air with a fighter prototype, the He-280. A year later, the Germans had an even better jet fighter, the Me-262, and that was the world's first jet plane to go into mass production. Britain's first jet, the Gloster Meteor twin-engined fighter, had its first test flight in March of 1943. From there, we've come all the way to this: Airbus Industries is developing what some are calling "The Super Jumbo." It's a double-decker plane that's 50% bigger than a Boeing 747, and it's capable of carrying 600 or 700 passengers. In the early days of their development, rocket engines and jet engines were closely related, and people made little distinction between them. A rocket is similar to a jet, except that it carries it's own supply of oxygen to create combustion. Jets get their oxygen from the air. Rockets get it from the oxygen tank they carry on board. That means a rocket can fly in space, where there is no oxygen. Robert Goddard's rocket experiments in the United States in the early 1930s were followed by Werner von Braun's rocket experiments in Nazi Germany, which led to the V2 rockets, which rained down on Britain during World War II. >> We knew that, uh, we had created a new means of warfare. >> NARRATOR: The rocket technology pioneered by Goddard and von Braun enabled future developments like the breaking of the sound barrier by Chuck Yeager in 1947, the launch by the USSR of Sputnik in 1957, and the Apollo 11 landing on the moon in 1969. Today, the three main rocket engines that power the space shuttle produce thrust equivalent to 37 million horsepower. That's as much as 23 Hoover Dams. Together, the engines consume 64,000 gallons of liquid hydrogen fuel per minute. The engines are movable and are used to steer the shuttle during flights. They also provide additional thrust for launch, supplementing the two huge booster rockets, which are jettisoned after takeoff. For decades now, advancements in the world of engine technology have led to bigger engines, but one of the most exciting areas today involves creating tiny engines that can fit on the tip of your finger. Microtechnology is a fast- growing area of research that has grown out of the miniaturization of electronic components. Some of the same manufacturing techniques are being used to build microtechnology engines. >> MARTIN SCHMIDT: There are actually advantages to making things small. As you miniaturize something, the weight goes down as the third power of the dimension, but the propulsive force goes down as the second power of the dimension. So as it gets smaller, the actual propulsion-to-weight goes up. >> NARRATOR: Professor Martin Schmidt of MIT has developed a turbo-jet engine the size of a postage stamp. And why did he want to do that? >> SCHMIDT: Well, first, it's awful fun. Second, there's propulsion applications: miniature aircraft, miniature satellites. >> NARRATOR: Professor Schmidt's tiny turbo-jet engine works exactly like the ones on a Boeing 747. >> SCHMIDT: This would be a turbine engine where air would come in through the center hole, and then fuel would be injected through a variety of these ports located here. The air and fuel would mix after going across a compressor, enter a combustion volume that's in a circular region that surrounds this, and then go across a set of turbine blades and be exhausted out through this port here. Inside of that lamination is this little disc, and that's the disc that'll spin at 1.5 million RPM. >> NARRATOR: Scientists at MIT believe this engine might power a tiny airplane with a wingspan of about three inches. Hundreds of such inexpensive, disposable micro-jet airplanes could be used for surveillance by the military, or for weather exploration. Another application scientists have great hopes for is the use of these tiny engines to generate electricity, so they could replace the heavy and less efficient battery packs in things like laptop computers. Some scientists are working on new micro-engine concepts that don't even exist at larger scales. >> RONNEY: But again, the target device is about shirt button size, and we hope will generate about 50 milowatts, which is enough to drive your cell phone or a personal organizer. You put a few of these together you could drive your laptop computer. If we take a fuel/air mixture, bring it into the center of a spiral heat exchanger like this, burn the fuel/air mixture in the middle, and then as the combustion products go out, use those outgoing products to preheat the fuel/air mixture that's coming in, you can actually get combustion under situations that otherwise the flame would extinguish. If we put devices called thermoelectric materials in these walls, we can actually use that to generate electrical power. >> NARRATOR: Some microtechnology engines have gears the size of a grain of pollen, and gear teeth the size of a red blood cell. If you want to make a microtechnology engine look big, just put it beside a nanotechnology motor. Nano-machines are so small, you can't even see them under a microscope. >> ROSS KELLY: Nano means a billionth. So things that are a billionth of a meter would be a nanometer, which is what is often discussed. >> NARRATOR: Line up ten atoms in a row and that row will be about one nanometer long. The roots of nanotechnology can be traced all the way back to 1959, when the late scientist Richard Feynman gave a legendary talk at the California Institute of Technology. It was entitled: "There's Plenty of Room at the Bottom." >> FEYNMAN: If we go down far enough, all of our devices can be mass produced so that they are absolutely perfect copies of one another. I want to build a billion tiny factories, models of each other, which are manufacturing simultaneously, drilling holes, stamping parts, and so on. >> KELLY: The issue was making things smaller and smaller, and that he didn't see any major violations of the basic physical laws like the laws of thermodynamics if you made something really small. >> FEYNMAN: It is my intention to offer a prize of $1,000 to the first guy who makes an operating electric motor which is only 1/64 inch cubed. >> NARRATOR: The prize was claimed years ago, but Professor Ross Kelly of Boston College wanted to go beyond Feynman's challenge of 1/64 inch cubed. >> KELLY: Coming up with a molecule, which is much, much smaller than that, is sort of the ultimate answer to his challenge. So it's taken us another 40 years to get down to the smallest possible scale. >> NARRATOR: Professor Kelly succeeded in arranging 78 atoms to create a motor that consists of one single, custom-built molecule. >> KELLY: The original design, of course much smaller than this, had two parts: something that was going to rotate that looks like a gear, has three blades on it, and something else that was going to function like the pall on a ratchet, and it was supposed to rotate like this. Each corner represents a carbon atom with a hydrogen atom on it. It's connected to the next corner by a bond between two carbon atoms. Next corner, another bond between two carbon atoms, and because of the laws of chemistry, one can predict how long the distances are going to be, and what the geometries are going to be. >> NARRATOR: In other words, even though it's so tiny he can't actually see it, Kelly knows he's created a single molecule whose atoms function like a motor. It took him four years to develop his motor molecule, but now it can be produced in batches... large batches. >> KELLY: Yeah, we had a flask with something like ten to the twentieth-- approximately a billion billion-- molecular motors in it. You could make as many as you want-- trillions and trillions and trillions. >> SCHMIDT: I think this will have an enormous impact. Being able to manipulate things at the micro and nano level enables us to build a nearly limitless number of devices and systems and those devices and systems will have, certainly, as many applications as the devices we built during the Industrial Revolution did. >> NARRATOR: Up next, cars that combine the best of two worlds: hybrids powered by both a gas engine, and an electric motor. "Engines" will return on<i> Modern Marvels.</i> >> ANNOUNCER: We now return to "Engines" on<i> Modern Marvels.</i> Hybrids, seen by some as the way of the future for automobiles, are propelled by both a gasoline engine and an electric motor. In hybrids like the Prius, introduced by Toyota in 1997, the engine and the motor can propel the car either separately or together. To reduce emissions, the electric motor is used to take the vehicle up to about 15 mph, and then the gas engine takes over. Electric cars put out no pollution, but the problem is they have to be charged up constantly. Hybrids offer some the advantages of the electric car, except you never have to plug it in at a recharging station. That's because hybrids charge up their own batteries while they're moving. >> HERMANCE: It's actually re-gen, putting energy from the tire through the motor, back into the battery pack. >> ANNOUNCER: With regenerative braking, the car slows down by using its electric motor as a generator. This creates drag on the drive line, and charges the battery. In other words, by functioning as a brake, the electric motor/generator actually creates energy, instead of wasting energy in heat loss like a regular brake. >> HERMANCE: As we turn the corner here, initial acceleration is motor, and as I step into the throttle, the engine starts. Green is charge, red is power. As I lift off the throttle, engine shuts off, and energy flow is from the tires through the motor back into the battery pack. >> ANNOUNCER: Toyota's competitor, Honda, began selling its two-seater hybrid called the Insight in 2000. Both cars sell for around $20,000. In Japan, over 34,000 hybrids have been sold since 1997. >> HEYWOOD: They're more expensive because you've got a battery and a motor to add to the engine that you're already paying for. And the benefits depend on the kind of driving these vehicles go through. So, for example, in Japan, they roughly doubt the fuel economy, because it's very congested, slow speed driving, lots of stopping and starting. When we come to the kind of driving we have in North America, less congested, we drive at higher speeds, longer distances, then the hybrid's not as attractive. >> ANNOUNCER: Trains have been using the hybrid concept for years. The locomotives we call "diesels" are really diesel- electric, with a powerful diesel engine generating electricity for the electric motors that turn the wheels. But the hybrid isn't the only bright hope on the horizon for automobiles. There is also... hydrogen. In 2000, BMW came out with the world's first production car run on either hydrogen or gasoline. When the car is switched over to run on hydrogen, it's like turning off the pollution. The only thing coming out of the exhaust pipe now is water vapor. But hydrogen comes at a price. >> HEYWOOD: The critical question is then, all right, if you want hydrogen, where do you get it from? Well, the most economic way now is to make hydrogen from natural gas. Natural gas has got carbon in it so, in producing hydrogen, we release the carbon into the atmosphere. That doesn't really help with the greenhouse gas problem. If we made hydrogen from nuclear power or perhaps solar energy, maybe we could find an economic way to do it that, that would let us produce hydrogen without releasing any carbon dioxide. >> ANNOUNCER: From steam engines to Stirling engines, from pistons to turbines, tracking the history of engine technology is a rewarding pilgrimage, a journey through a noble pantheon of man's greatest technological achievements. Ever since Hero built his first steam engine in ancient Greece, humans have been fascinated by the latest engines and motors. >> KELLY: I did it 'cause I thought it would be neat mostly, and I wasn't terribly worried about applications. >> ANNOUNCER: Undoubtedly that fascination will keep us connected to the future and fuel our ability to continue changing our world by inventing new kinds of engines... even if we're not quite sure what they're good for. <font color="#FFFF00"> Captioning sponsored by</font> <font color="#FFFF00"> A&E TELEVISION NETWORKS</font> Captioned by <font color="#00FFFF"> Media Access Group at WGBH</font> access.wgbh.org
