The Steam Locomotive was one of the Few Technologies that wasn’t replaced by a Superior Technology
Man first used stone tools about two and a half million years ago. We first controlled fire for our use about a million years ago. We first domesticated animals and began farming a little over 10,000 years ago. The Egyptians were moving goods by boats some 5,000 years ago. The Greeks and Romans first used the water wheel for power about 2,500 years ago. The Industrial Revolution began about 250 years ago. James Watt improved the steam engine about 230 years ago. England introduced the first steam locomotive into rail service about 210 years ago.
In the first half of the 1800s the United States started building its railroads. Helping the North to win the Civil War. And completing the transcontinental railroad in 1869. By 1890 there were about 130,000 miles of track crisscrossing the United States. With the stream locomotives growing faster. And more powerful. These massive marvels of engineering helped the United States to become the number one economic power in the world. As her vast resources and manufacturing centers were all connected by rail. These powerful steam locomotives raced people across the continent. And pulled ever longer—and heavier—freight trains.
We built bigger and bigger steam locomotives. That had the power to pull freight across mountains. To race across the Great Plains. And into our cities. With the chugging sound and the mournful steam whistle filling many a childhood memories. But by the end of World War II the era of steam was over. After little more than a century. Barely a blip in the historical record. Yet it advanced mankind in that century like few other technological advances. Transforming the Industrial Revolution into the Second Industrial Revolution. Or the Technological Revolution. That gave us the steel that built America. Electric Power. Mass production. And the production line. None of which would have happened without the steam locomotive. It was one of the few technologies that wasn’t replaced by a superior technology. For the steam locomotive was more powerful than the diesel-electric that replaced it. But the diesel-electric was far more cost-efficient than the steam locomotive. Even if you had to lash up 5 diesels to do the job of one steam locomotive.
The Hot Gases from the Firebox pass through the Boiler Tubes to Boil Water into Steam
The steam engine is an external combustion engine. Unlike the internal combustion engine the burning of fuel did not move a piston. Instead burning fuel produced steam. And the expansion energy in steam moved the piston. The steam locomotive is a large but compact boiler on wheels. At one end is a firebox that typically burned wood, coal or oil. At the other end is the smokebox. Where the hot gases from the firebox ultimately vent out into the atmosphere through the smokestack. In between the firebox and the smokebox are a bundle of long pipes. Boiler tubes. The longer the locomotive the longer the boiler tubes.
To start a fire the fireman lights something to burn with a torch and places it on the grating in the firebox. As this burns he may place some pieces of wood on it to build the fire bigger. Once the fire is strong he will start shoveling in coal. Slowly but surely the fire grows hotter. The hot gases pass through the boiler tubes and into the smokebox. And up the smoke stack. Water surrounds the boiler tubes. The hot gases in the boiler tubes heat the water around the tubes. Boiling it into steam. Slowly but surely the amount of water boiled into steam grows. Increasing the steam pressure in the boiler. At the top of the boiler over the boiler tubes is a steam dome. A high point in the boiler where steam under pressure collects looking for a way out of the boiler. Turned up into the steam dome is a pipe that runs down and splits into two. Running to the valve chest above each steam cylinder. Where the steam pushes a piston back and forth. Which connects to the drive wheels via a connecting rod.
When the engineer moves the throttle level it operates a variable valve in the steam dome. The more he opens this valve the more steam flows out of the boiler and into the valve chests. And the greater the speed. The valve in the valve chest moved back and forth. When it moved to one side it opened a port into the piston cylinder behind the piston to push it one way. Then the valve moved the other way. Opening a port on the other side of the piston cylinder to allow steam to flow in front of the piston. To push it back the other way. As the steam expanded in the cylinder to push the piston the spent steam exhausted into the smoke stack and up into the atmosphere. Creating a draft that helped pull the hot gases from the firebox through the boiler tubes, into the smokebox and out the smoke stack. Creating the chugging sound from our childhood memories.
The Challenger and the Big Boy were the Superstars of Steam Locomotives
To keep the locomotive moving required two things. A continuous supply of fuel and water. Stored in the tender trailing the locomotive. The fireman shoveled coal from the tender into the firebox. What space the coal wasn’t occupying in the tender was filled with water. The only limit on speed and power was the size of the boiler. The bigger the firebox the hotter the fire. And the hungrier it was for fuel. The bigger locomotives required a mechanized coal feeder into the firebox as a person couldn’t shovel the coal fast enough. Also, the bigger the engine the greater the weight. The greater the weight the greater the wear and tear on the rail. Like trucks on the highway railroads had a limit of weight per axel. So as the engines got bigger the more wheels there were ahead of the drive wheels and trailing the drive wheels. For example, the Hudson 4-6-4 had two axels (with four wheels) ahead of the drive wheels. Three axles (with 6 wheels) connected to the pistons that powered the train. And two axels (with four wheels) trailing the drive wheels to help support the weight of the firebox.
To achieve ever higher speeds and power over grades required ever larger boilers. For higher speeds used a lot of steam. Requiring a huge firebox to keep boiling water into steam to maintain those higher speeds. But greater lengths and heavier boilers required more wheels. And more wheels did not turn well in curves. Leading to more wear and tear on the rails. Enter the 4-6-6-4 Challenger. The pinnacle of steam locomotive design. To accommodate this behemoth on curves the designers reintroduced the articulating locomotive. They split up the 12 drive wheels of the then most powerful locomotive in service into two sets of 6. Each with their own set of pistons. While the long boiler was a solid piece the frame underneath wasn’t. It had a pivot point. The first set of drive wheels and the four wheels in front of them were in front of this pivot. And the second set of drive wheels and the trailing 4 wheels that carried the weight of the massive boiler on the Challenger were behind this pivot. So instead of having one 4-6-6-4 struggling through curves there was one 4-6 trailing one 6-4. Allowing it to negotiate curves easier and at greater speeds.
The Challenger was fast. And powerful. It could handle just about any track in America. Except that over the Wasatch Range between Green River, Wyoming and Ogden, Utah. Here even the Challenger couldn’t negotiate those grades on its own. These trains required double-heading. Two Challengers with two crews (unlike lashing up diesels today where one crew operates multiple units from one cab). And helper locomotives. This took a lot of time. And cost a lot of money. So to negotiate these steep grades Union Pacific built the 4-8-8-4 articulated Big Boy. Basically the Challenger on steroids. The Big Boy could pull anything anywhere. The Challenger and the Big Boy were the superstars of steam locomotives. But these massive boilers on wheels required an enormous amount of maintenance. Which is why they lasted but 20 years in service. Replaced by tiny little diesel-electric locomotives. That revolutionized railroading. Because they were so less costly to maintain and operate. Even if you had to use 7 of them to do what one Big Boy could do.
Pressure and Temperature have a Direct Relationship while Pressure and Volume have an Inverse Relationship
For much of human existence we used our own muscles to push things. Which limited the work we could do. Early river transport were barges of low capacity that we pushed along with a pole. We’d stand on the barge and place the pole into the water and into the river bed. Then push the pole away from us. To get the boat to move in the other direction.
In more developed areas we may have cleared a pathway alongside the river. And pulled our boats with animal power. Of course, none of this helped us cross an ocean. Only sail did that. Where we captured the wind in sails. And the wind pushed our ships across the oceans. Then we started to understand our environment more. And noticed relationships between physical properties. Such as the ideal gas law equation:
Pressure = (n X R X Temperature)/Volume
In a gas pressure is determined my multiplying together ‘n’ and ‘R’ and temperature then dividing this number by volume. Where ‘n’ is the amount of moles of the gas. And ‘R’ is the constant 8.3145 m3·Pa/(mol·K). For our purposes you can ignore ‘n’ and ‘R’. It’s the relationship between pressure, temperature and volume that we want to focus on. Which we can see in the ideal gas law equation. Pressure and temperature have a direct relationship. That is, if one rises so does the other. If one falls so does the other. While pressure and volume have an inverse relationship. If volume decreases pressure increases. If volume increases pressure decreases. These properties prove to be very useful. Especially if we want to push things.
Once the Piston traveled its Full Stroke on a Locomotive the Spent Steam vented into the Atmosphere
So what gas can produce a high pressure that we can make relatively easy? Steam. Which we can make simply by boiling water. And if we can harness this steam in a fixed vessel the pressure will rise to become strong enough to push things for us. Operating a boiler was a risky profession, though. As a lot of boiler operators died when the steam they were producing rose beyond safe levels. Causing the boiler to explode like a bomb.
Early locomotives would burn coal or wood to boil water into steam. The steam pressure was so great that it would push a piston while at the same time moving a connecting rod connected to the locomotive’s wheel. Once the piston traveled its full stroke the spent steam vented into the atmosphere. Allowing the pressure of that steam to dissipate safely into the air. Of course doing this required the locomotive to stop at water towers along the way to keep taking on fresh water to boil into steam.
Not all steam engines vented their used steam (after it expanded and gave up its energy) into the atmosphere. Most condensed the low-pressure, low-temperature steam back into water. Piping it (i.e., the condensate) back to the boiler to boil again into steam. By recycling the used steam back into water eliminated the need to have water available to feed into the boiler. Reducing non-revenue weight in steam ships. And making more room available for fuel to travel greater distances. Or to carry more revenue-producing cargo.
The Triple Expansion Steam Engine reduced the Expansion and Temperature Drop in each Cylinder
Pressure pushes the pistons in the steam engine. And by the ideal gas law equation we see that the higher the temperature the higher the pressure. As well as the corollary. The lower the temperature the lower the pressure. And one other thing. As the volume increases the temperature falls. So as the pressure in the steam pushes the piston the volume inside the cylinder increases. Which lowers the temperature of the steam. And the temperature of the piston and cylinder walls. So when fresh steam from the boiler flows into this cylinder the cooler temperature of the piston and cylinder walls will cool the temperature of the steam. Condensing some of it. Reducing the pressure of the steam. Which will push the piston with less force. Reducing the efficiency of the engine.
There was a way to improve the efficiency of the steam engine. By reducing the temperature drop during expansion (i.e., when it moves the piston). They did this by raising the temperature of the steam. And breaking down the expansion phase into multiple parts. Such as in the triple expansion steam engine. Where steam from the boiler entered the first cylinder. Which is the smallest cylinder. After it pushed the piston the spent steam still had a lot of energy in it looking to expand further. Which it did in the second cylinder. As the exhaust port of the first cylinder is piped into the intake port of the second cylinder.
The second cylinder is bigger than the first cylinder. For the steam entering this cylinder is a lower-pressure and lower-temperature steam than that entering the first cylinder. And needs a larger area to push against to match the down-stroke force on the first piston. After it pushes this piston there is still energy left in that steam looking to expand. Which it did in the third and largest cylinder. After it pushed the third piston this low-pressure and low-temperature steam flowed into the condenser. Where cooling removed what energy (i.e., temperature above the boiling point of water) was left in it. Turning it back into water again. Which was then pumped back to the boiler. To be boiled into steam again.
By restricting the amount of expansion in each cylinder the triple expansion steam engine reduced the amount the temperature fell in each cylinder. Allowing more of the heat go into pushing the piston. And less of it go into raising the temperature of the piston and cylinder walls. Greatly increasing the efficiency of the engine. Making it the dominant maritime engine during the era of steam.
The Combination of Force and Current of Moving Water on a Waterwheel produced Rotational Motion
Through most of history man has used animals for their source of power. To do the heavy work in our advancing civilizations. And they worked very well for linear work. Going long distances in a straight line. Such as pulling a carriage. Or a plow. Things done outdoors. A long place typically from where people ate and slept. So animal urine and feces wasn’t a great problem. But the closer we brought them to our civilized parts of society it became a problem. For it brought the smell, the flies and the disease closer to our civilized part of life.
Animals were good for linear work. But as civilization advanced rotational work became more important. For as machines advanced they needed to spin. The more advanced machines needed to spin at a fairly high revolutions per minute (rpm). We have used animals to produce rotational motion. By having them walk in a small circle. To slowly turn a mill stone. Or some other rotational machine. But it was inefficient. As animals can’t work continuously. Especially when walking in a circle. They have to rest. Eat. And they have to urinate and defecate. Making it unclean. And unhealthy.
The first great industrial advance was water power. Using a waterwheel. Spun by a current of water. Either a large force of water moving slow and steady. Like in a river. Or a small force of water moving fast and furiously. Like in a small waterfall. This combination of force and current produced rotational movement. And useable power. The waterwheel produced a rotational motion. This rotational motion drove a main drive shaft through a factory. Gear trains could speed up the rpm produced by a slow river current. Or reduce the rpm produced by a fast waterfall current. To produce a constant rotational speed. That was strong enough to drive numerous loads attached to the main drive shaft via belts and pulleys.
Compressed Air Systems allowed us to produce Rotational Motion at our Workstations
Water power was a great advancement over animal power. But it had one major drawback. You needed a moving current of water. Which meant we had to build our factories on the banks of rivers. Or under a waterfall. One of the reasons why our first industrial cities were on rivers. The steam engine changed that. With a steam engine providing our rotational motion we could put a factory pretty much anywhere. And the power of steam could do a lot more work than a moving current of water. So factories grew larger. But they still relied on a rotating main drive shaft. Then we started doing something else with our steam engines. We began compressing air with them.
A current of air can fill masts of sails and push ships across oceans. Air has mass. So moving air has energy. We’ve used windmills to turn millstones to crush our wheat. Where a large force of a slow moving wind current filled a sail. And pushed. But these small currents of air required large sails. If we compressed that volume of air down and pushed it through a very small air hose we could get a force at the end of that hose similar to what we got with a sail catching a large volume of air. This allowed us to create rotational motion at a workstation. Without the need of a rotating main drive shaft. We could connect an air hose to a handheld drill. And the compressed air in the air hose could direct a jet of high pressure air onto an ‘air-wheel’ inside the handheld drill. Which spun the ‘air-wheel’ at a very high rpm. Spinning the drill bit at a very high rpm.
Compressed air was a great advancement over a rotating main drive shaft. Instead of belts and pulleys connecting to the main shaft you just had to plug in your pneumatic tool to an air line. The steam engine’s rotational motion would drive an air compressor. Typically turning a crankshaft with two pistons attached to it. When a piston moves down the cylinder it draws air into the cylinder. When the piston moves up it compresses the air in the cylinder. The compressed air exits the cylinder and enters a large air tank. From this air tank they run a network of pipes throughout the factory. From these pipes hang air hoses with fittings that prevent the air from leaking out. Keeping the whole system charged under pressure. Then a worker takes his pneumatic tool. Plugs it into the fitting on a hanging air hose. As they snapped together you’ll hear a rush of air blow out. But once they snap together the joined fittings became airtight. When the worker presses the trigger on the pneumatic tool the compressed air blows out at a very high current. Spinning an ‘air-wheel’ that provides useful rotational
Electric Power generated Rotational Motion eliminated the need of Steam Engines and Compressed Air Systems
As good as this was there were some drawbacks. It takes time to produce steam when you first start up a steam engine. Once you have built up steam pressure then you can start producing rotational motion so the air compressor can start compressing air. This takes time, too. Then you need a lot of piping to push that air through. A piping system than can leak. It was a great system. But there was room for improvement. And this last improvement we made was so good that we haven’t made another in over 100 years. A new way to provide rotational motion at a workstation. Without requiring a steam boiler. And air compressor. Or a vast piping system charged with air pressure. Something that allows us to plug in and go right to work. Without waiting for steam or air pressure to build. And that last advancement was, of course, electric power.
When voltage (force) pushes an electrical current through a wire we get useable power. Generators at a distant power plant produce voltages that push current through wires. And these wires can run anywhere. In the air. Or underground. They can travel great distances at dangerous high voltages and low currents. And we can use transformers to change them to a safer low voltage and a higher current in our factories. And our homes. Where we can use that force and current to produce useful rotational motion. Using electric and magnetic fields inside an electrical motor.
Animals were a poor source of rotational power. The windmill and the waterwheel were better. The windmill could go anywhere but the rotational motion was only available when the wind blew. Waterwheels provided continuous rotational motion but they only worked where there was moving water. Keeping our early factories on the rivers. The steam engine let us build factories where there was no moving water. While an air compressor driven by a steam engine made it much easier to transfer power form the power source to the workstation. While electric power made that transfer easier still. It also eliminated the need of the steam engine and the pneumatic piping system. Allowing us to create rotational motion right at the point of work. With the ease of plugging in. And pressing a trigger. Allowing machines to enter our homes to make our lives easier. Like the vacuum cleaner. The clothes washer. And the air conditioner. None of which your average homeowner could operate if we depended on a main drive shaft in our house. Or a steam engine driving a pneumatic system.
A Waterwheel, Shaft, Pulleys and Belts made Power Transmission Complex
The history of man is the story of man controlling and shaping our environment. Prehistoric man did little to change his environment. But he started the process. By making tools for the first time. Over time we made better tools. Taking us into the Bronze Age. Where we did greater things. The Sumerians and the Egyptians led their civilization in mass farming. Created some of the first food surpluses in history. In time came the Iron Age. Better tools. And better plows. Fewer people could do more. Especially when we attached an iron plow to one horsepower. Or better yet, when horses were teamed together to produce 2 horsepower. 3 horsepower. Even 4 horsepower. The more power man harnessed the more work he was able to do.
This was the key to controlling and shaping our environment. Converting energy into power. A horse’s physiology can produce energy. By feeding, watering and resting a horse we can convert that energy into power. And with that power we can do greater work than we can do with our own physiology. Working with horse-power has been the standard for millennia. Especially for motive power. Moving things. Like dragging a plow. But man has harnessed other energy. Such as moving water. Using a waterwheel. Go into an old working cider mill in the fall and you’ll see how man made power from water by turning a wheel and a series of belts and pulleys. The waterwheel turned a main shaft that ran the length of the work area. On the shaft were pulleys. Around these pulleys were belts that could be engaged to transfer power to a work station. Where it would turn another pulley attached to a shaft. Depending on the nature of the work task the rotational motion of the main shaft could be increased or decreased with gears. We could change it from rotational to reciprocating motion. We could even change the axis of rotation with another type of gearing.
This was a great step forward in advancing civilization. But the waterwheel, shaft, pulleys and belts made power transmission complex. And somewhat limited by the energy available in the moving water. A great step forward was the steam engine. A large external combustion engine. Where an external firebox heated water to steam. And then that steam pushed a piston in a cylinder. The energy in expanding steam was far greater than in moving water. It produced far more power. And could do far more work. We could do so much work with the steam engine that it kicked off the Industrial Revolution.
Nikola Tesla created an Electrical Revolution using AC Power
The steam engine also gave us more freedom. We could now build a factory anywhere we wanted to. And did. We could do something else with it, too. We could put it on tracks. And use it to pull heavy loads across the country. The steam locomotive interconnected the factories to the raw materials they consumed. And to the cities that bought their finished goods. At a rate no amount of teamed horses could equal. Yes, the iron horse ended man’s special relationship with the horse. Even on the farm. Where steam engines powered our first tractors. Giving man the ability to do more work than ever. And grow more food than ever. Creating greater food surpluses than the Sumerians and Egyptians could ever grow. No matter how much of their fertile river banks they cultivated. Or how much land they irrigated.
Steam engines were incredibly powerful. But they were big. And very complex. They were ideal for the farm and the factory. The steam locomotive and the steamship. But one thing they were not good at was transmitting power over distances. A limitation the waterwheel shared. To transmit power from a steam engine required a complicated series of belts and pulleys. Or multiple steam engines. A great advance in technology changed all that. Something Benjamin Franklin experimented with. Something Thomas Edison did, too. Even gave us one of the greatest inventions of all time that used this new technology. The light bulb. Powered by, of course, electricity.
Electricity. That thing we can’t see, touch or smell. And it moves mysteriously through wires and does work. Edison did much to advance this technology. Created electrical generators. And lit our cities with his electric light bulb. Electrical power lines crisscrossed our early cities. And there were a lot of them. Far more than we see today. Why? Because Edison’s power was direct current. DC. Which had some serious drawbacks when it came to power transmission. For one it didn’t travel very far before losing much of its power. So electrical loads couldn’t be far from a generator. And you needed a generator for each voltage you used. That adds up to a lot of generators. Great if you’re in the business of selling electrical generators. Which Edison was. But it made DC power costly. And complex. Which explained that maze of power lines crisscrossing our cities. A set of wires for each voltage. Something you didn’t need with alternating current. AC. And a young engineer working for George Westinghouse was about to give Thomas Edison a run for his money. By creating an electrical revolution using that AC power. And that’s just what Nikola Tesla did.
Transformers Stepped-up Voltages for Power Transmission and Stepped-down Voltages for Electrical Motors
An alternating current went back and forth through a wire. It did not have to return to the electrical generator after leaving it. Unlike a direct current ultimately had to. Think of a reciprocating engine. Like on a steam locomotive. This back and forth motion doesn’t do anything but go back and forth. Not very useful on a train. But when we convert it to rotational motion, why, that’s a whole other story. Because rotational motion on a train is very useful. Just as AC current in transmission lines turned out to be very useful.
There are two electrical formulas that explain a lot of these developments. First, electrical power (P) is equal to the voltage (V) multiplied by the current (I). Expressed mathematically, P = V x I. Second, current (I) is equal to the voltage (V) divided by the electrical resistance (R). Mathematically, I = V/R. That’s the math. Here it is in words. The greater the voltage and current the greater the power. And the more work you can do. However, we transmit current on copper wires. And copper is expensive. So to increase current we need to lower the resistance of that expensive copper wire. But there’s only one way to do that. By using very thick and expensive wires. See where we’re going here? Increasing current is a costly way to increase power. Because of all that copper. It’s just not economical. So what about increasing voltage instead? Turns out that’s very economical. Because you can transmit great power with small currents if you step up the voltage. And Nikola Tesla’s AC power allowed just that. By using transformers. Which, unfortunately for Edison, don’t work with DC power.
This is why Nikola Tesla’s AC power put Thomas Edison’s DC power out of business. By stepping up voltages a power plant could send power long distances. And then that high voltage could be stepped down to a variety of voltages and connected to factories (and homes). Electric power could do one more very important thing. It could power new electric motors. And convert this AC power into rotational motion. These electric motors came in all different sizes and voltages to suit the task at hand. So instead of a waterwheel or a steam engine driving a main shaft through a factory we simply connected factories to the electric grid. Then they used step-down transformers within the factory where needed for the various work tasks. Connecting to electric motors on a variety of machines. Where a worker could turn them on or off with the flick of a switch. Without endangering him or herself by engaging or disengaging belts from a main drive shaft. Instead the worker could spend all of his or her time on the task at hand. Increasing productivity like never before.
Free Market Capitalism gave us Electric Power, the Electric Motor and the Roaring Twenties
What electric power and the electric motor did was reduce the size and complexity of energy conversion to useable power. Steam engines were massive, complex and dangerous. Exploding boilers killed many a worker. And innocent bystander. Electric power was simpler and safer to use. And it was more efficient. Horses were stronger than man. But increasing horsepower required a lot of big horses that we also had to feed and care for. Electric motors are smaller and don’t need to be fed. Or be cleaned up after, for that matter.
Today a 40 pound electric motor can do the work of one 1,500 pound draft horse. Electric power and the electric motor allow us to do work no amount of teamed horses can do. And it’s safer and simpler than using a steam engine. Which is why the Roaring Twenties roared. It was in the 1920s that this technology began to power American industry. Giving us the power to control and shape our environment like never before. Vaulting America to the number one economic power of the world. Thanks to free market capitalism. And a few great minds along the way.
To Keep People on Trains they Undercharge Passengers and make up the Difference with Government Subsidies
We built some of our first factories on or near a river. Where we could use that river’s current to turn a waterwheel. To provide a rotational motion that could do work for us. We transmitted that rotational motion via a main drive shaft through a factory where it could drive machinery via belts and pulleys. Once we developed the steam engine to provide that rotational motion we could move our factories anywhere. Not just on or near a river. Giving us greater freedom. And permitting greater economic growth. As we put those steam engines onto rails. That transported freight and people all across the country.
Trains are nice. But expensive. To go anywhere on a train you need train tracks going there. But train tracks are incredibly expensive to lay. And maintain. If you ever stared at a set of train tracks you probably noticed something. There aren’t a lot of trains going by on them. When a train stops you when you’re running late or bringing home dinner it may feel like trains are always stopping you. But if you parked at those same tracks for a few hours you wouldn’t see a lot of trains. Because even the most polished rails (the more train traffic the more polished the rails) are unused more than they are used.
This is why trains are very expensive. Tracks cost a lot of money to lay and maintain. Costs that a railroad has to recoup from trains using those rails. And when you don’t have a lot of trains on those rails you have to charge a lot for the trains that do travel on them. A mile-long train pulling heavy freight can pay a lot of revenue. And make a railroad profitable. But passenger trains are not a mile long. And carry few people. Which means to make money on a passenger train you’d have to charge more for a ticket than people would pay. To keep people on trains, then, they have to undercharge passengers. And make up the difference with government subsidies.
A Crank Shaft and Combustion Timing takes Reciprocal Motion of Pistons and Converts it into Rotational Motion
This is why people drive places instead of taking the train. It’s far less expensive to take the car. And there are roads everywhere. Built and maintained by gas taxes, licenses and fees. And if you’ve ever driven on a road you probably noticed that there are a lot of cars, motorcycles, trucks and buses around you. With so many vehicles on the roads they each can pay a small amount to build and maintain them. Which is something the railroads can’t do. Only trains can travel on train tracks. But cars, motorcycles, trucks and buses can all travel on roads. This is why driving a car is such a bargain. Economies of scale.
To operate a train requires a massive infrastructure. Dispatchers control the movement of every train. Tracks are broken down into blocks. The dispatchers allow only one train in a block at a time. They do this for a couple of reasons. Trains don’t have steering wheels. And can take up to a mile to stop. So to operate trains safely requires keeping them as far apart from each other as possible. Traveling on roads is a different story. There are no dispatchers separating traffic. Cars, motorcycles, trucks and buses travel very close together. Starting and stopping often. Traveling up to high speeds between traffic lights. With motorcycles and cars weaving in and out among trucks and buses. Avoiding traffic and accidents by speeding up and slowing down. And steering.
Driving a car today is something just about anyone 16 and older can do. Thanks to the remarkable technology that makes a car. Starting with the internal combustion engine. The source of power that makes everything possible. Just like those early waterwheels the source of that power is rotational motion. But instead of a river providing the energy an internal combustion engine combusts gasoline to push pistons. A crank shaft and combustion timing takes that reciprocal motion of the pistons and converts it into rotational motion. Spinning a drive shaft that provides power to drive the car. As well as power all of its accessories.
The Friction of Brake Shoe or Pad on Steel slows the Car converting Kinetic Energy into Heat
The first cars required a lot of man-power. It took great strength to rotate the hand-crank to start the engine. Sometimes the engine would spit and cough. And kick back. Breaking the occasional wrist. Once started it took some leg-power to depress the clutch to shift gears. It took a little upper body strength to turn the steering wheel. And some additional leg-power to apply the brakes to stop the car. In time we replaced the hand-crank with the electric starter. We replaced the clutch and gearbox with the automatic transmission. We added power steering and power breaks to further reduce the amount of man-power needed to drive a car. Today a young lady in high heels and a miniskirt can drive a car as easily and as expertly as the first pioneers who risked bodily harm to drive our first cars.
The internal combustion engine can spin a crankshaft very fast and accelerate a car to great speeds. Which is good for darting in and out of traffic. But traffic occasional has to stop. Which is easier said than done. For a heavy car moving at speed has a lot of kinetic energy. You can’t destroy energy. You can only convert it. And in the case of slowing down a car you have to convert that kinetic energy into heat. When you press the brake pedal you force hydraulic fluid from a master cylinder to small cylinders at each wheel. As fluids cannot compress when you apply a force to the fluid that force is transmitted to something than can move. In the case of stopping a car it is either a brake shoe that presses against the inside of the car’s wheels. Or a caliper that clamps down on a disc. The friction of brake shoe or pad on steel slows the car. Converting that kinetic energy into heat. In some cases of excessive braking (on a train or a plane) the heat can be so excessive that the wheels or discs glow red.
So as the internal combustion engine and the brakes play their little games of speeding up and slowing down a car the rotational power of the crankshaft drives other accessories. Such as power steering. Where a belt and pulley transfers that rotational power to a power steering pump. The pump pushes fluid to the steering gear to assist in turns. Another belt and pulley connects an alternator to the crankshaft to produce electricity to provide power for the car’s electrical systems. And to charge the battery so it can spin the automatic starter. Another belt and pulley connects another compressor to the crankshaft. This one for air conditioning. That allows us to alight from our cars shower-fresh on the hottest and most humid days of the year. And, finally, antifreeze removes the heat of combustion from the internal combustion engine and transfers it to a heating core inside the passenger compartment. Allowing a warm and comfortable drive home during the coldest of days. As well as keeping our windows free of snow and ice so we can see to drive safely on our way home. Through bumper to bumper traffic. Something we do day after day with the ease of doing the laundry. Thanks to the remarkable technology that we take for granted that makes a car.
With the Steam Engine we could Build Factories Anywhere and Connect them by Railroads
Iron has been around for a long time. The Romans used it. And so did the British centuries later. They kicked off the Industrial Revolution with iron. And ended it with steel. Which was nothing to sneeze at. For the transition from iron to steel changed the world. And the United States. For it was steel that made the United States the dominant economy in the world.
The Romans mined coal in England and Wales. Used it as a fuel for ovens to dry grain. And for smelting iron ore. After the Western Roman Empire collapsed, so did the need for coal. But it came back. And the demand was greater than ever. Finding coal, though, required deeper holes. Below the water table. And holes below the water table tended to fill up with water. To get to the coal, then, you had to pump out the water. They tried different methods. But the one that really did the trick was James Watt’s steam engine attached to a pump.
The steam engine was a game changer. For the first time man could make energy anywhere he wanted. He didn’t have to find running water to turn a waterwheel. Depend on the winds. Or animal power. With the steam engine he could build a factory anywhere. And connect these factories together with iron tracks. On which a steam-powered locomotive could travel. Ironically, the steam engine burned the very thing James Watt designed it to help mine. Coal.
Andrew Carnegie made Steel so Inexpensive and Plentiful that he Built America
Iron was strong. But steel was stronger. And was the metal of choice. Unfortunately it was more difficult to make. So there wasn’t a lot of it around. Making it expensive. Unlike iron. Which was easier to make. You heated up (smelted) iron ore to burn off the stuff that wasn’t iron from the ore. Giving you pig iron. Named for the resulting shape at the end of the smelting process. When the molten iron was poured into a mold. There was a line down the center where the molten metal flowed. And then branched off to fill up ingots. When it cooled it looked like piglets suckling their mother. Hence pig iron.
Pig iron had a high carbon content which made it brittle and unusable. Further processing reduced the carbon content and produced wrought iron. Which was usable. And the dominate metal we used until steel. But to get to steel we needed a better way of removing the residual carbon from the iron ore smelting process. Something Henry Bessemer discovered. Which we know as the Bessemer process. Bessemer mass-produced steel in England by removing the impurities from pig iron by oxidizing them. And he did this by blowing air through the molten iron.
Andrew Carnegie became a telegraph operator at Pennsylvania Railroad Company. He excelled, moved up through the company and learned the railroad business. He used his connections to invest in railroad related industries. Iron. Bridges. And Rails. He became rich. He formed a bridge company. And an ironworks. Traveling in Europe he saw the Bessemer process. Impressed, he took that technology and created the Lucy furnace. Named after his wife. And changed the world. His passion to constantly reduce costs led him to vertical integration. Owning and controlling the supply of raw materials that fed his industries. He made steel so inexpensive and plentiful that he built America. Railroads, bridges and skyscrapers exploded across America. Cities and industries connected by steel tracks. On which steam locomotives traveled. Fueled by coal. And transporting coal. As well as other raw materials. Including the finished goods they made. Making America the new industrial and economic superpower in the world.
Knowing the Market Price of Steel Carnegie reduced his Costs of Production to sell his Steel below that Price
Andrew Carnegie became a rich man because of capitalism. He lived during great times. When entrepreneurs could create and produce with minimal government interference. Which is why the United States became the dominant industrial and economic superpower.
The market set the price of steel. Not a government bureaucrat. This is key in capitalism. Carnegie didn’t count labor inputs to determine the price of his steel. No. Instead, knowing the market price of steel he did everything in his powers to reduce his costs of production so he could sell his steel below that price. Giving steel users less expensive steel. Which was good for steel users. As well as everyone else. But he did this while still making great profits. Everyone was a winner. Except those who sold steel at higher prices who could no longer compete.
Carnegie spent part of his life accumulating great wealth. And he spent the latter part of his life giving that wealth away. He was one of the great philanthropists of all time. Thanks to capitalism. The entrepreneurial spirit. And the American dream. Which is individual liberty. That freedom to create and produce. Like Carnegie did. Just as entrepreneurs everywhere have been during since we allowed them to profit from risk taking.
Rent-Seeking Captains of Industry and Commerce give Capitalism a Bad Name
Once upon a time you lived, worked and died all within a short walk from each other. In feudalism people owned land and lived well. The landed aristocracy. And other people (the peasants) worked the land. But did not live as well as those who owned it. For it was back-breaking work for long hours with no respite except in death. For those who worked the land belonged to the land. Just as the trees and fields and rivers did. Peasants belonged to the land and the land belonged to the landowner. The peasants couldn’t leave. And they couldn’t work hard to provide a better life for their children. For they were bond to the land as their patents were. With no choice but to work the land like their parents did.
This was how life was before we started to use power to make our work easier. We had long been using animal power to do things we didn’t have the strength or the endurance to do. Such as pulling a plow. Or a wagon full of goods. Or to travel great distances more quickly than we could by walking. Harnessing the power of moving water changed all of that. For a river moves constantly. And when you place a waterwheel in moving water you can convert the linear motion of the water into rotational motion. This rotational motion could turn a main shaft running though a factory. Belts and pulleys could transfer this power to workstations throughout the factory floor. And these powered workstations could do far more work than a person could. Lumberjacks could transport logs down a river to a lumber mill. Where a waterwheel could spin a saw that made lumber out of those logs at such a rate that great cities could arise around these mills. Cities with other factories powered by waterwheels. And homes.
So it’s no surprise that our early cities grew up on rivers. Both for water power. And the ability to use them to ship bulk goods. Ship transport. Something even animals weren’t good at. It is in these cities that wealth and political power grew. Centers of industry and commerce. Creating great wealth for those who controlled the resources that made all of that possible. So another aristocracy grew. Rent-seeking captains of industry and commerce. Who give capitalism a bad name. Who use their political power to maximize their profits. And buy favors from those in power to protect their particular interests. Such as using the power of government to create monopolies for themselves. But advancing technology made that harder to do. Especially the steam engine. And the railroad.
The Steel and Heavy Manufacturing Industries required a Massive Infrastructure and Regionally Located Raw Materials
Control of rivers, ports and harbors provided a great opportunity to amass wealth at other people’s expense. For when economic activity centered on water it made land around that water very valuable. Which concentrated wealth and power on the rivers. Until the steam engine replaced the waterwheel. And the railroad provided a way to transport people and goods inland. So not only did cities grow up along the waterways they grew up along the rail lines. Those controlling these resources still had great wealth and power. But they also offered competition. And more economic liberty. For while there can only be one Tennessee River flowing through Chattanooga, Tennessee, there can be more than one railroad running through Chattanooga. Which made Chattanooga an important city to hold during the American Civil War. For there was a great rail junction in that city. Giving anyone who controlled the city access to any part of the Confederacy.
While the steam engine and railroad allowed industries to grow anywhere in the country some industries still clustered in regional areas. Such as the steel industry. It required three ingredients to make steel. Iron ore, coke (coal cooked into hard charcoal briquettes) and limestone. To make steel you use 6 parts iron ore, 2 parts coke and 1 part limestone. Iron ore was plentiful around Lake Superior. Because it takes a lot of iron ore and a lot of iron ore is located around Lake Superior the steel makers built their mills long the Great Lakes. In Milwaukee. Chicago. Gary. Detroit. Toledo. Cleveland. Or in places like Pittsburgh where coal and iron ore deposits surround the city. These cities made up the Manufacturing Belt. Places with access to bulk ore shipping (on Great Lakes freighter or river barge). And where the steel mills arose so did heavy industry that built things from that steel. From structural steel. To automobiles.
For a while these new industries dominated the economic landscape. Big, heavy industries that couldn’t move. Concentrating money and political power. Giving rise to organized labor. Who took advantage of the fact that these heavy industries could not move. Negotiating lucrative union contracts. With generous pay and benefits. Raising the price of steel and the things we made from steel. Like automobiles. Making the rank and file like rent-seekers of old. Looking to personally benefit from their near-monopoly conditions. Like those early captains of industry and commerce. Life was good for awhile for the rank and file. Who lived very well. And better than most American workers. Thanks to those monopoly-like conditions in these steel and heavy manufacturing industries. Allowing them to charge high prices for their goods to pay for those generous pay and benefits. As there was no competition. For the steel and heavy manufacturing industries required a massive infrastructure and an abundant supply of regionally located raw materials, making it very difficult for a new competitor to open for business. At least, in the United States.
High Costs and Low Efficiencies have shuttered most of America’s Steel Making Past
Foreign competition changed all that. And large ocean-going ships. So new industries in other countries with lower labor costs could manufacture these goods and ship them to the United States. And did. Challenging the monopoly-like conditions of the rent-seeking steel and heavy manufacturing industries. So the rent-seekers turned to government for protection. And got it. Import tariffs. Which raised the price of those imported goods to the higher price level of the domestic goods. Which did two things. Insulated the domestic manufacturers from market pressures allowing them to continue with the status quo. And forced the foreign manufacturers to find less costly and more efficient ways to make their goods to counter those import tariffs.
So what happened? Technology advanced in these industries overseas while they stagnated in the US. The US didn’t invest in new technologies like they did in the previous century to find better ways to do things. Because they didn’t have to. While the foreign competitors worked harder to find better ways to do things. Because they had to. As they weren’t insulated from market forces. The Japanese invested in robotics. Transforming their auto industry. Improving quality and lowering costs. Making their cars as good if not better than the Americans did. And selling them at a competitive price even with those import protections. So what did these US actions to protect the domestic manufacturers do? Changed the Manufacturing Belt to the Rust Belt.
The big steel cities in America are no more. High costs and low efficiencies have shuttered most of America’s steel making past. Gone is the era of the sprawling steel mill. Today it’s the minimill and continuous casting. Small and efficient steel mills with small labor forces that can make small batches. Thanks to their electric arc furnaces that are easy to turn on and off. Unlike the big blast furnaces that took a while to reach operating temperatures and when they did they didn’t shut them down for years. Making it difficult to adjust to falling demand. Like the minimills could. Which helped save the steel industry by finally adopted technology that allowed it to sell at market prices. Making it harder for the rent-seekers these days. But better for consumers. Because of this relentless march of technology. That allows us to continuously find better ways to do things.
The Steam Engine pumped Water from Mines allowing them to go Deeper as they followed Veins of Coal
Petroleum is the lifeblood of advanced economies. It propels our airplanes, ships, trains, trucks, ambulances, air ambulances, fire trucks, cars, etc. It moves everything. Our sick and injured. Our families. Our food. Our goods. The raw materials that build the world we live in. You would not recognize the world if we removed petroleum from it. There would be no aviation. No emergency vehicles that could respond in minutes. No family car. But we could still have ships and trains. Because before petroleum there was coal.
Before the Industrial Revolution we used animals to move people and things. We were using fuels for other things. But not to move people and goods. Until there was a problem getting that fuel. The British were mining coal near the coast. But there was a problem. As the coal veins they mined moved under the sea they filled with water. Limiting how far they could follow those veins. They had a pump. Driven by a crude steam engine. But it just didn’t do the job very well. Until a man came along and improved it. James Watt. Who improved that crude steam engine. And changed the world.
The steam engine pumped water from coal mines allowing them to go deeper as they followed veins of coal. But the steam engine had other uses. They could power a drive shaft in a factory. Allowing us to build factories anywhere. Not just by moving water that drove a waterwheel. And using a steam engine to move a train allowed us to connect these factories with other factories. And to the stores in the cites that bought the things they built. Steam-powered tractors replaced the horse and plow on the farm. While steam locomotives brought coal from distant coal mines to our homes we burned for heat. Coal was everywhere. We had a coal-based economy. And a coal-based life. The more we used the more we had to mine. Thanks to the coal-fired steam engine we could mine a lot of it. And did. It powered the Industrial Revolution. And powers our modern economy today. Because coal even powers the engines that replaced the steam engines in our factories.
The two largest Electrical Loads in a Coal Mine are the Water Pumps and the Ventilation Fans
We’ve replaced the steam engines in our factories with the electric motor. Instead of having a main drive shaft through the factory and a system of belts and pulleys we put an electric motor at each workstation. And connected it to the electric grid. Greatly increasing our productivity. And the electric power to drive these electric motors came predominantly from coal-fired power plants. Coal has never been more important in the modern economy. It provides about half of all electric power. Followed by natural gas and nuclear power at about 20% each (though natural gas is on the rise). Hydroelectric dams provide less than 10% of our electric power. And everything else provides less than 5%.
Just as the steam engine made mining more efficient so did electric power. Mines can go deeper because electric pumps can more efficiently pump water out of the mines. And large fans can circulate the air underground so miners can breathe. As well as disperse any buildups of methane gas or coal dust. Before they can explode. Which is one of the hazards of mining a flammable and, at times, explosive material. The hazard is so real that you will not find ventilation fans inside the mine. You’ll find water pumps deep in the mines. But not the ventilation fans. Because if there is a fire or an explosion underground they’ll need to protect those fans from damage so they will still be able to ventilate the mine. For if the mine fills with smoke surviving a fire or an explosion will matter little if you cannot breathe.
The two largest electrical loads in a coal mine are the water pumps and the ventilation fans. Mines consume enormous amounts of electric power. And most of it goes to fighting the water seepage that will fill up a mine if not pumped out. And making the mines habitable. Electric power also runs the hoists that haul the coal to the surface. Transports miners to and from the mines. And runs the mining equipment in a confined space without any hazardous fumes. As critical as this electric power is to survive working in such an unfriendly environment more times than not the power they use comes from a coal-fired power plant. A plant they feed with the very coal they mine. Because it’s dependable. That electric power will always be there.
Coal will always let you Charge your Electric Car Overnight and Surf the Web in the Morning
But we just don’t mine coal underground. We also dig it up from the surface. With strip mining. Most of the coal we use today comes from great strip mines out West. Where they use mammoth machines called draglines to scrape away soil to get to the coal. And then they scrape out the coal. These machines are as big as ships and actually have crew quarters inside them. They even name them like ships. They operate kind of like a fishing rod with a few minor differences. Instead of a rod there is a boom. Instead of nylon fishing line there is a steel cable up to two inches in diameter. And instead of a hook there is a bucket big enough to hold a 2-car garage. The operator ‘throws’ the bucket out by running it out along the boom. Then drops it in the dirt. Then drags the bucket back. The massive scale of the dragline requires an enormous amount of power. And the power of choice? Electric power. Often produced by the very coal they mine. Some of these machines have electric cables even bigger around than the cables that drag their buckets. At voltages of 10,000 to 25,000 volts. Drawing up to 2,000 amps.
These draglines can mine a lot of coal. But it’s a lower-quality coal than some of our eastern coal. Which has a higher energy content. But eastern coal also has a higher sulfur content. Which requires more costs to make it burn cleaner. In fact, before any coal ships today we wash it to remove slate as well as other waste rock from the coal. And it is in this waste rock where we find much of the sulfur. So the washing makes the coal burn cleaner. As well as raise the energy content for a given quantity of coal by removing the waste that doesn’t burn. There are a few ways they do this. But they all involve water. Therefore, at the end of the process they have to dry the coal by spinning it in a large cylindrical centrifuge. So a lot happens to coal between digging it out of the ground and loading it on a unit train (a train carrying only one type of cargo) bound to some power plant. And chances are that it will go to a power plant. For our coal-fired power plants buy about 80% or so of all coal mined. So if you see a coal train it is probably en route to a coal-fired power plant.
Coal created the modern world. And it powers it to this day. From the first steam engines that dewatered mines to the coal-fired power plants that power the massive server farms that hold the content of the World Wide Web. Yes, coal even powers the Internet. As well as our electric cars. For only coal will be able to meet the electric demand when everyone starts plugging their car into the electric grid overnight. Because solar power doesn’t work at night. And wind power is even less reliable. For if it’s a still night you’ll have no charge to drive to work in the morning. But if you plugged into coal you’ll always be able to charge your electric car overnight. And surf the web in the morning.
We started the First Cars with a Hand Crank and Nearly Broke an Arm if the Hand Crank Kicked Back
The king of car engines is the internal combustion engine (ICE). We tried other motors such as a steam engine. But a steam engine is a heat engine. Meaning it first has to get hot enough to boil water into steam. Which meant any trip in a car took a little extra time to bring the boiler up to operating temperatures. Boilers tend to be big and heavy. And dangerous. Should something happen and a dangerous level of steam pressure built up they could explode. Despite those drawbacks, though, a steam engine-powered car took you places. And as long as there was fuel for the firebox and water for the boiler you could keep driving.
Another engine we tried was the electric motor. These didn’t have any of the drawbacks of a steam engine. You didn’t have to wait for a boiler to get to operating temperatures before driving. Nothing was in danger of exploding. An electric motor was lighter than a cast-iron boiler. And an electric motor could make a car zip along. However, an electric motor requires continuous electricity to operate. Provided by charged batteries. Which didn’t last long. And took hours to recharge. Giving the electric car limited range. And little convenience. For the heavier it was and/or the faster you went the faster you drained those batteries. Which could be a problem taking the family on vacation. But they worked well in a forklift on a loading dock. Because of the battery-power they produced no emissions so they’re safe to use indoors. They had limited auxiliary systems to run (other than a horn and maybe a light). And when they were running low on charge you rarely needed to drive more than 20 or 30 feet to a charging station.
The first ICE-powered cars took some manly strength to operate. They didn’t have power brakes, power steering, automatic transmissions or starters. We started the first ICE-powered cars with a hand crank. That took a lot of strength to turn. And if it backfired while starting the kick of the handle could easily break a wrist or an arm. Putting a damper on any Sunday afternoon drive. This limited the spread of the automobile. They were complex machines that required some strength to operate. And they could be very dangerous. Then along came the electric starter. Which was an electric motor that spun the ICE to life. Making the car much safer to start. Expanding the popularity of the automobile. For there was no longer a good chance that you could break your arm trying to start it. And through the years came all those accessories making it easier and more comfortable to drive. Today automatic transmissions, power steering, power brakes, headlights, interior lights, power locks, power windows, powered seats, a fairly decent audio system, heat, air conditioning and more are standard on most cars. All effortless powered by that internal combustion engine.
Current Battery Technology does not give the All-Electric Car a Great Range
The reason why an ICE can do all of this is because gasoline is a very concentrated energy source. It doesn’t take a lot of it to go a long way. And it can accelerate you up a hill. It even has the energy to pass someone on a hill. It’s a fuel source we can take with us. A small amount of it stores conveniently and safely in a gas tank slung underneath a car. And when it’s empty it takes very little time to refill. A ten minute stop at a gas station and you’re back on the road able to drive another 500 miles or so. Even in the dark of night with headlights blazing. While keeping toasty warm in the winter. Or comfortably cool in the summer. Things an electric battery just can’t do. So why would we even want to trade one for the other? In a word—emissions.
The internal combustion engine pollutes. The more fuel a car burns the more it pollutes. So to cut pollution you try to make cars burn less fuel. You increase the fuel economy. And you can do that in a couple of ways. You can cut the weight of the vehicle. And put in a smaller engine. Because a smaller engine can power a lighter car. But a smaller car carries fewer people comfortably. And can carry less stuff. A motor cycle gets very good fuel economy but you can’t take the family on a Sunday drive on one. And you can’t pack up your things on a motorcycle when going off to college. So the tradeoff between fuel economy and weight has consequences.
An electric car does not pollute. At all. (Though the power plant that charges its batteries does pollute. A lot.) But current battery technology does not give the all-electric car a great range. Typically coming in at less than 75 miles per charge. Which is great if you’re operating a forklift on a loading dock. But it’s pretty bad if you’re actually driving on a road going someplace. And hope to return. The heavier the car is the shorter that driving range. If you want to use your headlights, heater or air conditioner it’ll be shorter still. On top of this short range recharging your battery isn’t like stopping at the gas station for 10 minutes. No. What one typically does is pray that he or she gets home. Then plugs in. And by morning the car would be fully charge for another 75 miles or so of driving.
To Maximize the Benefit of a Hybrid you’d want to Carry the Absolute Minimum of Batteries to Serve your Needs
So all-electric cars are clean but they won’t really take us places. The ICE-powered car will take us places but it’s not really clean. Enter the gas/electric hybrid. Which combines the best of the all-electric car (clean) and the best of the ICE-powered car (range). There are a few varieties. The parallel hybrid has both an ICE and an electric motor connected to a transmission that powers the wheels. The ICE also drives a small generator. Batteries power the electric motor. And a gas tank feeds the ICE. The generator keeps the batteries charged. The battery powers the electric motor to accelerate the car from a stop. After a certain speed the small ICE takes over. When the car needs to accelerate the electric motor assists the ICE. The small ICE has excellent fuel economy thus reducing emissions. The electric motor/battery provides the additional horsepower when needed to compensate for an undersized ICE. And the gasoline-powered engine provides extended range.
In addition to the parallel hybrid there is the series hybrid. It has the same parts but they are connected differently. The series hybrid is more like a diesel-electric locomotive. Gasoline feeds the ICE. The ICE drives a generator. The generator charges the batteries and/or drives the electric motor. The electric motor drives a transmission that spins the wheels. This car drives on batteries until the charge runs out and then switches over to the ICE. For short commutes this provides excellent fuel economy. For longer drives (well over 75 miles or so) it’s more like a standard ICE-powered car with a roundabout way of turning the wheels.
Then there’s the plug-in variety. In addition to all of the above you can plug your car into a charger to further save on gasoline use and reduce emissions (produced by the car; not by the electric power plant). Letting you recharge the battery overnight in a standard 120V outlet. In a slightly shorter time with a 240 volt outlet. And quicker still in a 480 volt outlet. If your commute to and from work is 50 miles or less you can probably charge up at home and not have to carry a charger with you (to convert the AC power to the DC power of the batteries). Saving even more weight. But if you plan on charging on the road you’ll need to carry a charger with you. Adding additional weight. Which will, of course, reduce your battery range. Also, you can adjust the number of batteries to match your typical daily commute. The shorter your commute the less charge you need to store. Which lets you get by on fewer batteries. Greatly reducing the weight of the car (and extending your battery range). A gallon of gas weighs about 7 pounds and can take a car 30 miles or more. You would need about 1,000 pounds of batteries to provide a similar range. So range doesn’t come cheap. To maximize the benefit of a hybrid you’d want to carry the absolute minimum of batteries to serve your needs. Knowing that if you got a new job with a longer commute you could rely on the ICE in your hybrid to get you to work and back home safe again.
By burning Coal to Boil Water into Steam to Move a Piston we could Build a Factory Anywhere
We created advanced civilization by harnessing energy. And converting this energy into working power. Our first efforts were biological. Feeding and caring for large animals made these animals strong. Their physiology converted food and water into strong muscles and bones. Allowing them to pull heavy loads. From plowing. To heavy transportation. To use in construction. Of course the problem with animals is that they’re living things. They eat and drink. And poop and pee. Causing a lot of pollution in and around people. Inviting disease.
As civilization advanced we needed more energy. And we found it in wind and water. We built windmills and waterwheels. To capture the energy in moving wind and moving water. And converted this into rotational motion. Giving us a cleaner power source than working animals. Power that didn’t have to rest or eat. And could run indefinitely as long as the wind blew and the water flowed. Using belts, pulleys, cogs and gears we transferred this rotational power to a variety of work stations. Of course the problem with wind and water is that you needed to be near wind and water. Wind was more widely available but less reliable. Water was more reliable but less widely available. Each had their limitations.
The steam engine changed everything. By burning a fuel (typically coal) to boil water into steam to move a piston we could build a factory anywhere. Away from rivers. And even in areas that had little wind. The reciprocating motion of the piston turned a wheel to convert it into rotational motion. Using belts, pulleys, cogs and gears we transferred this rotational power to a variety of work stations. This carried us through the Industrial Revolution. Then we came up with something better. The electric motor. Instead of transferring rotational motion to a workstation we put an electric motor at the work station. And powered it with electricity. Using electric power to produce rotational motion at the workstation. Electricity and the electric motor changed the world just as the steam engine had changed the world earlier. Today the two have come together.
You can tell a Power Plant uses a Scrubber by the White Steam puffing out of a Smokestack
Coal has a lot of energy in it. When we burn it this energy is transformed into heat. Hot heat. For coal burns hot. The modern coal-fired power plant is a heat engine. It uses the heat from burning coal to boil water into steam. And as steam expands it creates great pressure. We can use this pressure to push a piston. Or turn a steam turbine. A rotational device with fins. As the steam pushes on these fins the turbine turns. Converting the high pressure of the steam into rotational motion. We then couple this rotational motion of the steam turbine to a generator. Which spins the generator to produce electricity.
Coal-fired power plants are hungry plants. A large plant burns about 1,000 tons of coal an hour. Or about 30,000 pounds a minute. That’s a lot of coal. We typically deliver coal to these plants in bulk. Via Great Lakes freighters. River barges. Or unit trains. Trains made up of nothing but coal hopper cars. These feed coal to the power plants. They unload and conveyor systems take this coal and create big piles. You can see conveyors rising up from these piles of coal. These conveyors transport this coal to silos or bunkers. Further conveyor systems transfer the coal from these silos to the plant. Where it is smashed and pulverized into a dust. And then it’s blown into the firebox, mixed with hot air and ignited. Creating enormous amounts of heat to boil an enormous amount of water. Creating the steam to turn a turbine.
Of course, with combustion there are products left over. Sulfur impurities in the coal create sulfur dioxide. And as the coal burns it leaves behind ash. A heavy ash that falls to the bottom of the firebox. Bottom ash. And a lighter ash that is swept away with the flue gases. Fly ash. Filters catch the fly ash. And scrubbers use chemistry to remove the sulfur dioxide from the flue gases. By using a lime slurry. The flue gases rise through a falling mist of lime slurry. They chemically react and create calcium sulfate. Or Gypsum. The same stuff we use to make drywall out of. You can tell a power plant uses a scrubby by the white steam puffing out of a smokestack. If you see great plumes puffing out of a smokestack there’s little pollution entering the atmosphere. A smokestack that isn’t puffing out a plume of white steam is probably spewing pollution into the atmosphere.
Coal is a Highly Concentrated Source of Energy making Coal King when it comes to Electricity
When the steam exits the turbines it enters a condenser. Which cools it and lowers its temperature and pressure. Turning the steam back into water. It’s treated then sent back to the boiler. However, getting the water back into the boiler is easier said than done. The coal heats the water into a high pressure steam. So high that it’s hard for anything to enter the boiler. So this requires a very powerful pump to overcome that pressure. In fact, this pump is the biggest pump in the plant. Powered by electric power. Or steam. Sucking some 2-3 percent of the power the plant generates.
Coupled to the steam turbine is a power plant’s purpose. Generators. Everything in a power plant serves but one purpose. To spin these generators. And when they spin they generate a lot of power. Producing some 40,000 amps at 10,000 to 30,000 volts at a typical large plant. Multiplying current by power and you get some 1,200 MW of power. Which can feed a lot of homes with 100 amp, 240 volt services. Some 50,000 with every last amp used in their service. Or more than twice this number under typical loads. Add a few boilers (and turbine and generator sets) and one plant can power every house and business across large geographic areas in a state. Something no solar array or wind farm can do. Which is why about half of all electricity produced in the U.S. is generated by coal-fired power plants.
Coal is a highly concentrated source of energy. A little of it goes a long way. And a lot of it produces enormous amounts of electric power. Making coal king when it comes to electricity. There is nothing that can match the economics and the logistics of using coal. Thanks to fracking, though, natural gas is coming down in price. It can burn cleaner. And perhaps its greatest advantage over coal is that we can bring a gas-fired plant on line in a fraction amount of the time it takes to bring a coal-fired plant on line. For coal-fired plants are heat engines that boil water into steam to spin turbines. Whereas gas-fired plants use the products of combustion to spin their turbines. Utilities typically use a combination of coal-fired and gas-fired plants. The coal-fired plants run all of the time and provide the base load. When demand peaks (when everyone turns on their air conditioners in the evening) the gas-fired plants are brought on line to meet this peak demand.