Megawatt Windmill

Megawatt wind turbines are windmills capable of generating a megawatt or more of electricity and feeding it into the electrical grid.


Palmer Putnam was an MIT geologist. Literature notes he has “no formal education or experience in wind power.” Of course, that was true for everybody in the 1930s. There was no such thing as a wind engineer.

Earlier, in the 1880s, Thomas Perry created the Aermotor company that generated a small amount of electricity for disconnected rural farmers. Aermotor windmills generated enough electricity to run a radio or a small pump. Up to the present time, these types of windmills, with their multiple blades, are familiar in pictures of old farms or movies.

However, Putnam’s windmill was entirely different. His 75-ft (23 meters) blades were, by far, the largest ever built. Russians like building big things and previously the Soviet Union built the largest windmill generator that produced 100-kilowatts, naming it Balaklava. Putnam was aiming for ten-times that amount of electrical output.

General Electric was supportive of the idea and supplied the generator, limited capital, and connections to people. The Dean of Engineering at MIT, Vannevar Bush, reviewed Putnam’s work and agreed the megawatt windmill was a real possibility. A company that built turbines for dams funded most of the project, envisioning a growth opportunity in renewables beyond dams.

However, as Putnam worked to harness winds, the winds of war were blowing across the US. There was a feeling it was only a matter of time until the US entered WWII, where engineers and metal were needed for war.

Like today’s wind turbines, there were only two large blades. When he finally turned the windmill on, in late 1941, it generated 1.25 megawatts.


In 1943, the windmill broke and was stalled until after WWII due to a lack of materials and people. After the war, it functioned for three weeks and broke again, due to a sub-quality wartime repair. Finally, in 1945 a study showed wind power would cost 50% more than coal-fired electrical plants and the project was abandoned.

Today, in 2019, wind power costs less than any other form of power including coal. Windmills require no fuel and emit nothing, unlike coal-fired plants with their harmful emissions. The largest windmills operate offshore and generate 9.5 megawatts of power. Every year, windmills increase in size and capacity while lowering price.

Blade Assembly
Palm Putnam and Stanton Dornbirer of the S. Morgan Smith Co.

Audion Tube

The Audion acts as an amplifier, transforming quiet electric signals into loud ones.


In 1906, Lee de Forest invented the “three-electrode Audion” vacuum tube.

In 1906, Lee de Forest invented the “three-electrode Audion” vacuum tube. The Audion acts as an amplifier, transforming quiet electric signals into loud ones.

Originally de Forest wasn’t quite sure if the Audion had any practical application. That quickly changed. Audions efficiency boost voice over telephones, enabling long-distance calls. They make radios (and, later, phonographs, televisions, and anything else that produces sound) louder. They improve reception. Audion amplifying tubes caused countless noise complaints until digital transistors overtook them.

Patent Battles

de Forest famously fought epic patent battles to protect his Audion tube patent. The two most well-known include one with vacuum tube inventor John Fleming and another with radio inventor Edwin Armstrong. During these fights, de Forest admitted he did not know how or why his tube worked nor did he see any practical use for it. However, as the first person to invent and patent the tube he claimed broad rights to the patent and license it. After prolonged litigation that included three trips to the US Supreme Court they ruled for de Forest.

The de Forest patent war brings up a recurring and never-ending question: what is the purpose of a patent? The US Constitution clarifies patents exist “To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries.” Other countries have similar reasoning.

However, when the inventor of a thing sees no purpose for it and does not understand how it works do patents really promote the progress of science? US patents were initially issued by the Secretary of State, Thomas Jefferson. Except he did not like patents and processed applications slowly if at all. Steamboat inventor John Fitch received a patent after a long wait. However, the patent also issued to three others including two who did no research at all. Similarly, he sat on the application for Eli Whitney’s cotton gin. By the time the patent issues knockoffs abounded. However, steamboats and cotton gins both flourished.

Vacuum Tube (Diode)

Working for the Edison Electrical Light Company of England, Sir John Fleming invented the diode, a vacuum tube at the heart of all early electronics. Radios, television, telephones, computers – virtually every electronic we’re familiar with today – was first built with diodes.

Diodes are typically vacuum tubes, though some have specialized gasses in them. They conduct electricity, moving it from the cathode to the anode.

Early diodes evolved from lightbulbs. Electrons flow free in lightbulbs. Their purpose is to emit light and there is no need to shepherd the energy. Diodes enable the controlled flow of electrons. This enables all sorts of nifty tricks when tied together into circuits.

Compared to modern electronics, Diodes were enormous and also enormously power-hungry. Since they were tubes that typically operate at high heat they also tend to burn out, like old-fashioned pre-LED lightbulbs. Diodes often consumed as much as 100 volts. An iPhone, with billions of more circuits, consumes five volts.

Diodes typically contained additional electrodes, called grids, to control the flow of electricity and form circuits. Diodes with one grid are called a triode, because electricity flows from the cathode to the anode but can be diverted by the grid. Tetrode’s are four-grid diodes, etc…

Despite that Fleming was a physicist he was an avid anti-evolutionist. He profited from the invention of his diode, and subsequent discoveries, and left the bulk of his fortune to Christian charities serving the poor.

Transistors eventually replaced the vacuum tube.

Heavy-Duty DC Motor / Trolley / Subway

Faraday proved an electric motor was possible but, like his many inventions, neither scaled the idea up nor commercialized it. Voltaic piles at that time were the sole source of electricity. Because they produced little electricity high-power motors seemed pointless.


The new field of electricity interested Sprague, a Navy officer. While serving in the Navy, Sprague invented a new type of dynamo generator and installed it on his ship, the USS Lancaster, powering an electric call system.

In 1883, Sprague resigned his Naval commission and joined Edison. He did well working for Edison, especially demonstrating how mathematical modeling can be used in place of some real-world experimentation. This reduced the time and cost of building Edison’s electric plant.

Sprague’s real interest was in electric motors. Noting the large and filthy steam-engines of the day, he imagined a world where heavy-duty electric motors ran everything from streetcars to factories. Edison was the boss and his interest was in lighting, not motors. When Sprague suggested motors, Edison shrugged him off. Rather than arguing, Sprague quit and formed the Sprague Electric Railway & Motor Company.

A New Motor

Sprague quickly innovated two major electrical components. First was a high-power electric motor strong enough to move streetcars or other heavy objects. Second came a regenerative braking system where the brakes act as a generator, returning power back to the grid. The combination enabled streetcars, elevators, subways, and about a century later hybrid cars.

Soon, Sprague’s motors powered streetcars powerful enough to climb the hills of Richmond, Virginia, or pull cables hoisting streetcars up the hills of San Francisco. By 1889, Sprague engines powered 110 “electric railways.” It wouldn’t be long until people realized that, due to no exhaust, the electric trains are suitable for underground use. Tunnels were bored and streets opened to dig out space for underground electric trains.

Sprague also tried convincing long-distance train operators that electricity is a better option than coal but, at the time, the motors were not strong enough. Eventually, a half century later, trains converted from coal to electric motors powered by diesel generators.

Sprague created brush-based DC motors. Eventually, Nicola Tesla would invent the brushless AC motor. However, to this day, the New York City subway and countless others run on DC electricity rather than the easier to manage AC. To this day, Parisian subway trains are referred as “les rames Sprague” (Sprogue trains).

Dry Cell Battery

Dry cell batteries are the batteries the world is familiar with, the one’s that run portable electronics. Voltaic pile batteries, that preceded dry-cell batteries, required constant maintenance.


To contextualize this era, the telegraph was gaining widespread adoption. However, there was no power grid to run the telegraphs at this time. The first power plant, Edison’s Pearl Street Station, did not go online until September 1882. Electrification of the US, and the rest of the world took decades after that.

Therefore, telegraphs ran on batteries. During the US Civil War, there were entire wagon trains full of wet-cell Voltaic Pile batteries powering telegraphs. However, there were problems with Voltaic Piles. They were extremely heavy, required constant maintenance, and operated most efficiently with highly caustic sulfuric acid. Riding over dirt roads in wooden buggies filled with giant vats of sulfuric acid, especially in a warzone, was a lousy job.

Given the high utility of telegraphs, and their immense ability to generate wealth, scientists suddenly had a financial incentive to find better methods to generate electricity. One of these methods was the dry-cell battery, a disposable battery with no liquid inside. Dry cell batteries were lighter, safer, and vastly more efficient than Voltaic piles. It’s important to remember Volta’s batteries were a scientific experiment, not a commercial product.

Leclanché Cell Battery

In 1866, French engineer Georges Leclanché built a better battery to power telegraphs. It contained less caustic liquid and was enclosed; there was no need to continually add liquid. His battery was called the Leclanché cell, since batteries were individual cells rather than a large liquid vat. Leclanché batteries vastly reduced the cost of battery maintenance.

In 1885, German scientist Carl Gassner improved the Leclanché cell by figuring out how to remove all liquid, an entirely dry battery. Gassner is the patent holder of dry cell batteries in Europe and the US. Japanese businessman Sakizou Yai claims to have invented a better dry cell batter and certainly built a large company selling the batteries.

Lithium-Ion Battery

Lithium-Ion Batteries (LIBs) power everything from smartphones to power tools and electric cars. Entire cities store power generated during the day, via solar panels, for use at night from large lithium battery arrays. One of the largest factories in the world, the Tesla Gigafactory, is devoted solely to manufacturing Lithium-Ion batteries.


An ability to recharge relatively rapidly and deliver a steady stream of electricity without overheating makes LIBs the workhorse of portable power. The batteries are so popular that there are fears of an upcoming lithium shortage.

There were several iterations of lithium batteries and the technology is still evolving.

John Goodenough, a professor of engineering at the University of Texas at Austin, is the primary inventor of the battery. Goodenough has an interesting history. He graduated summa cum laude in mathematics from Yale. After WWII, the army ordered him back to the US to attend graduate school in physics.

Goodenough spent his life in academia but, in the 1970s, decided to focus on batteries. Like many, he was angered by the OPEC-led energy crisis and also concerned about the smog and pollution internal combustion engines caused. A strong battery could power cars, he reasoned and switched his attention to battery technology.

Patent Wars

Goodenough was 57 years old in 1980 when he invented the Lithium-Ion battery. Sony commercialized the technology and the new battery became a blockbuster. Despite the commercial success, Goodenough earned no royalties from his battery. However, there was a massive patent battle between various companies and people involved in creating and commercializing the battery.

In 2017, Goodenough, age 94, announced he has created a successor solid-state battery that lasts longer, holds more energy, is more environmentally friendly (it contains no cobalt), and is safer than his original battery. As of 2019, he is still alive and still working on building a better battery.

Light Emitting Diode (LED)

“New York City and you’re flying in an airplane and you see all these lights. And you think lights, lights, lights, lights, lights.”

Nick Holonyak

Nick Holonyak Jr.’s mom was an orphan. His dad was a coal miner. After a stint in the mine’s, Nick decided school sounded like a fine idea.

Holonyak was the first graduate student of two-time Nobel Prize winner John Bardeen, inventor of the semiconductor.

Holonyak worked at General Electric in the laser group. Lasers, to that time, were infrared and invisible to the naked eye. In 1962, Holonyak invented a Light Emitting Diode (LED) that emitted a red light, making the laser light visible. To this day, all red lasers are based on Holonyak’s work.

In 1963 Holonyak left GE for academia, joining the faculty at the University of Illinois at Urbana-Champaign. GE, along with other competitors, built a substantial LED business that still exists. Additionally, other companies went on to use the technology to improve devices from lasers to television and computer screens.

GE build from their own LED light business. However, with the innovation of LED light bulbs that last for decades, their core lighting business is destined for extinction as the need for replacement bulbs is expected to wane. As of 2019, GE has been working for years to sell the light-bulb business that dates back to Edison and launched the business. However, thanks to the longevity of LED lights, they so far failed to find a buyer.

Markedly, Holonyak has no received a Nobel Prize despite that the prize was awarded to the inventor of blue LED’s, a derivative of Holonyak’s work.

“They’re so damn cheap.”

Nick Holonyak

Solar Cells

Solar Cells produce electricity from sunlight.

Early History

In 1873 and 1874, scientists noticed that selenium reacted with light to produce electricity. During the 1870s William Adams and Richard Day proved that light plus selenium generated current. Eventually, famous German scientist Werner von Siemens (founder of Siemens) was excited about the possibility of solar cells in the late 1800s. Indeed, in 1905, Einstein explained what made solar cells work, “light quanta” – that we now call photons.

Subsequently, by the early 1930s, scientists were enamored with solar cells: “…in the not distant future, huge plants will employ thousands of these plates to transform sunlight into electric power…that can compete with hydroelectric and steam-driven generators in running factories and lighting homes” wrote German scientist Bruno Lange in 1931.

However, as the cells proved inefficient, interest waned. By 1949, scientists had all but given up hope on a reasonably efficient solar cell.

Eventually, five years later, scientists Calvin Fuller and Gerald Pearson of Bell Labs were working with silicon to create transistors. They noticed that silicon could generate electricity.

In a different area, scientist Daryl Chapin was tasked with the remote generation of electricity. He started to experiment with selenium but faced the same problem earlier scientists had, efficiency of just 0.5 percent. Pearson told Fuller he was wasting his time with selenium and to try silicon, which ran at 2.3 percent efficiency, much higher.

Bell labs continued working on solar cells and, on Apr. 25, 1954, displayed a 21-inch Ferris wheel that ran on a solar-powered battery. The press loved the concept: unlimited, free energy from the sun.

More Recently

Subsequently, solar cells have since fared better and worse, becoming popular in the 1970s only to disappear again. Eventually, they reemerged in the 2000s as a viable source of electricity.

As of 2018, solar cells have efficiency as high as 22.5%. As efficiency increases and price decreases, solar is becoming one of the least expensive options to generate electricity; only wind energy costs less.

Nuclear Power

One of the great physicists, Fermi won the Nobel Prize in 1938, at the age of 37. No sooner did he receive his prize than he fled from his home in fascist Italy to New York City, taking US citizenship.

Eventually, Fermi and the other nuclear scientists had convinced President Roosevelt that the Nazis could and would produce a nuclear bomb, which led the US government to grant them virtually unlimited funding.

On Dec. 2, 1942, Fermi’s reactor ー under the squash court at the University of Chicago ー went critical to become the first self-sustaining nuclear reaction.

Fermi would eventually work on the Manhattan Project, to develop nuclear weapons and the Atomic Energy Commission.

Like many early nuclear scientists, Fermi died of cancer at the young age of 53.

Eventually, in 1951, Walter Zinn connected a Fermi reactor to the rest of the equipment needed to generate electricity. This created the first working nuclear power plant.

Three Phase Power

One extra wire allows transmission of triple the amount of electricity via three-phase power. With three wires rather than two, electrical operators can transmit triple the electricity. “Polyphase” is another term for three-phase power.

Three phase power usually transmits enormous amounts of electricity. These are the large transmission lines on tall polls. Electricity is converted into two-phase power, more practical for home use, at endpoint stations. Both heavy industry and electric cars use powerful three-phase induction engines.

Markedly, three phase power results in significant cost savings due to the reduced amount of wire needed.

Meters that regulated and measured the electricity spanned many patents. Eventually, Westinghouse acquired virtually all of them to compete with Edison, eventually lighting up the 1893 Chicago World’s Fair. Tesla’s patents proved to be the most valuable.