Tuesday, 30 April 2013

Niagara Falls and the History of Electricity

To see the role of Niagara Falls in electricity, we have to go back to electricity's humble beginnings.
Most of us know that Thomas Edison was credited with the invention of the incandescent light bulb. It was a technological achievement that ultimately changed the way we lived as our activities started to encroach well beyond sunset.
However, did you know that Edison almost undermined the electricity revolution by championing the DC electric current for electricity networks?
DC current (or "direct current" as opposed to AC current or "alternating current") pertains to the flow of electrons directly from the source (like a battery) to the load (like a light bulb). You can kind of think of it like water flowing from a reservoir high up on a hill and streaming downhill in a channel or creek towards a waterwheel, where the force of the moving water turns the wheel and does work for you. If you were to look at a DC current on an oscilloscope (which displays voltage as a function of time), it would be more or less a straight line.

Ever the entrepreneur and inventor, Edison sought to leverage his patents and control the electricity delivery (transmission) to customers needing to light up the night without noxious and staining fumes from gas lamps or candles (see how the power grid for transmission and distribution of electricity works).
However, DC has its drawbacks as it tended to be limited in range as it was susceptible to energy loss (as heat) as it moved across the wires carrying the electricity (wires could be modeled as resistors, which generate what's called Joule heating when current passes through it). Many of the clients who employed DC had to be located within one mile of the DC generators as a result. The voltage was also low voltage since Edison positioned it as "safe" and worry-free from electrocution.
George Westinghouse and Nikola Tesla (who ironically was Edison's secretary) challenged Edison and championed AC current.
AC pertains to the alternating direction of flow of electricity from source to load. Periodically, the current moves in one direction, then flows in the opposite direction. If you were to look at an AC current on an oscilloscope, you would see a sine wave wiggling about zero volts in the vertical middle (i.e. the mean or average).
It turned out that AC had many benefits and it allowed engineers to capitalize on breakthroughs at the time. This included Tesla's induction motor (which exploited Faraday's Law to convert magnetic fields into an AC electrical current - the basis of most generators today) as well as William Stanley's commercial transformer (which allowed the ability to "step-up" or "step-down" AC current - the basis for transmission of electricity over long distances and overcoming line losses) among others.
Edison tried to vilify AC as dangerous. He even encouraged capital punishment to use AC for electric chairs to make the public associate AC with death and thus turn to Edison's "safer" DC.
After several years of fighting a public relations, legislative, financial, and technological battles, it turned out that Niagara Falls would play a crucial role in tilting the battle of AC versus DC in favor of AC.
The falls was like the scene for the climax of the epic battle between AC and DC. Both camps saw the powerful waterfall as a means to demonstrate the superiority of one technology over the other. The stage was set for numerous power companies to try to divert water upstream from the falls and route them to turbines which in turn generated the electricity.
Edison's limited range DC meant customers had to be close to the falls to attain the benefits of the DC generators he championed. This is the basis for what's known as distributed generation, where users had to be located close to the source of the power though you could have multiple generators each serving a localized community in a de-centralized network.
Meanwhile, the Tesla/Westinghouse camp were able to directly use the AC generated by the turbines spun by the force of the Niagara River diversions, step up the voltages with a transformer (up to hundreds of thousands of volts), send it long distances (to Buffalo nearly 30 miles away and eventually to Manhattan where there's Broadway and Wall Street), and step down the voltages with a transformer to a more usable form for lights and eventually other inventions to come like machines (for manufacturing), radios, televisions, calculators, etc.

While the hydroelectric schemes at Niagara Falls weren't the first to demonstrate Tesla's generation motors or that it was possible to use hydro for electricity, it was the first of its kind for industrial use.
Thus, the stage was set for the adoption of AC, which eventually paved the way for energy monopolists (like Samuel Insull), federal involvement in regulating (and in many cases enhancing monopolies) of electricity, standardizing the electricity (so you could plug your electronics in one area and it would still work elsewhere in the country; our current American standard is 120V AC oscillating at 60Hz), and the expansion of the electricity grid across the Nation as well as the world.
In essence, the AC current paved the way for centralized generation and consequent distribution and transmission of electricity to customers. Thus, the energy utilities started to gain influence and power, which still remains to this day.
Today, we take for granted that we plug in our electronics to the wall socket and get electricity to power our computers, chargers, TVs, lights, microwaves, refrigerators, etc. Yet it was a waterfall that was instrumental in the eventual adoption of our electricity grid, and thus changed our lives forever.
Now while Edison ultimately lost the technological battle between AC and DC, he might end up getting the last laugh as environmental, political, and economic pressures are steering the electricity industry back towards de-centralized distributed generation (though not totally in favor of low voltage DC as Edison would've liked). This opens the possibility for clean renewable energy (solar, wind, geothermal, wave, etc.) to compete with energy utility monopolies for power generation and distribution (which is currently by coal-fired plants, natural gas, nuclear, and hydroelectric) by being more efficient, environmentally friendly, and cheaper. Whether this happens sooner rather than later largely depends on all the backroom dealings, money exchanges, promises, and debating amongst government and industry interests (this includes lobbyists and politicians taking money from industry) who make the decisions as to how the Nation moves forward on this matter.

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