Electrical Power Generation at Niagara
The simple answer is: most of it.
At any given moment the water diverted upstream from the falls, to run the various power plants, is anywhere from 60 to 75%. That’s an average of 1,200,000 gallons (4,542,500 liters) of water per second with only 600,000 gal/sec (2,271,250 liters/sec) left to run over the Horseshoe Falls and a mere 150,000 gal/sec (567,811 liters/sec) for the American Falls. Although it may seem as though the Falls are being deprived of their natural flow, the water that remains to cover the falls is still an impressive sight. Many waterfall enthusiasts agree that reduced flow makes for waterfalls with more “character.”
Although mills have been using diverted water from the Falls as a source of hydraulic power since 1759, it wasn’t until 1882 that the Falls were used to generate electricity.
The Niagara Falls Hydraulic Power & Manufacturing Company, which constructed a canal for hydraulic power generation nearly 20 year prior, began operating a small electrical plant in Niagara Falls, New York in 1882. The plant, which generated direct current (DC), could only distribute current a distance of 2 miles. Despite this limitation, it was a big hit for both its utility and as a tourist attraction. It was this small plant that demonstrated the potential for hydro-electric power from Niagara Falls.
In the mid 1800s, renowned engineering genius Nikola Tesla developed a system of alternating current (AC) that would allow for generated electricity to be distributed over distances much further than direct current (DC). When the electric-generating industry was in its infancy one of the major hurdles to its success was distribution. Plants are expensive to build. In order to make it profitable, it would have to have a lot of customers. AC power (as advanced as it was at the time) would allow a plant in one location to serve multiple cities tens of miles away. Tesla was a strong advocate of the adoption of AC as the standard of power distribution. The formidable Thomas Edison thought that DC was the future and promoted it heavily.
The Niagara Falls Power Company, backed by strong investors such as John Jacob Astor, J.P. Morgan, William Vanderbilt and others began construction on a large-scale electric plant on the US side of the Falls. NFPC offered a $100,000 prize for anyone who could develop a method for the long distance transfer of electricity. After much controversy and many failed proposals, Westinghouse Electric and Manufacturing Company, with Tesla as a consultant, won the contract to build Tesla’s polyphase AC system for the new power station. In 1894, when the Niagara Falls Power Company’s Powerhouse #1 went online and power was distributed as far as Buffalo, NY, it was clear that AC power was here to stay.
Tesla’s contribution to Niagara power generation has been honored with a bronze statue on Goat Island in Niagara Falls State Park in Niagara Falls, New York. Another statue lies across the border in Queen Victoria Park.
There are a total of 5 power stations on the Niagara River. 2 of which are on the US side and 3 on the Canadian side.
Easily, the Robert Moses Power Plant in Lewiston, NY for both its physical size and capacity.
It holds back a 1,900 acre, 22 billion gallon reservoir of Niagara’s waters.
During construction, over 12 million cubic yards of rock was excavated and twenty workers died.
Hydroelectric power plants are usually built around waterfalls because they take advantage of the drop in water, more precisely: the power of gravity, to generate electricity. The power plants at Niagara divert some of the river’s flow from above the falls using canals or tunnels. The diverted water is carried around the Falls (not over it) downriver to where the river is separated from the diverted water by a large cliff or drop. Here a power plant acts as a contained waterfall. It allows the diverted water to fall down the cliff, through the plant and its turbines and into the river below. The diverted water is stored in large reservoirs upstream from the power plants. This acts as a buffer in case the river dries up or there are other disruptions in the water diversion system. Think of these reservoirs as banks of stored water-energy.
Before the water runs through the plant, large objects like logs, most fish, and ice must be strained out to avoid clogs and damage to the plant’s equipment. On its way through the plant, the water runs through turbines that spin under the pressing force of the falling water. Turbines are like reverse motors. Think of a propeller motor for an electric toy boat. Electric current runs to the motor which charges electromagnets. The magnets are aligned so that when they are charged with electricity, they repel each other and spin on an axis. This axis spins the propeller and pushes the boat. Now reverse this. Instead of the propeller pushing the water, the water now pushes the propeller (or turbine) which spins the magnets and outputs electricity as a result.
After spinning the turbines the water meets the river again.
On the US side, plants have a capacity of roughly 2.7 million Kilowatts, while the Canadian side’s combined capacity is close to 2.2 million kilowatts.
This number does not include the two Decew Falls stations in St. Catherines, ON that have a total capacity of roughly 167,000 kilowatts generated from the Welland River’s drop over the Niagara escarpment.
The numbers above represent capacity, not actual power generation. The power generated by the plants on the Niagara varies on a daily, monthly and yearly basis. Factors that affect actual power generation can be anything from demand, to river flow, to tourism season.
Most of the water that would flow naturally over Niagara Falls is diverted for power generation (See “How much of the water is being diverted for power generation“). Not only does this reduction tame the appearance of the cataract, but it also curbs the erosive action and thus recession speed of the Falls, which has slowed to a relative crawl since the power plants were constructed.
The diversion of the Niagara River is acceptable to most tourists. Having never seen the Falls at full flow, most people just accept them the way they are – perhaps not even giving it a second thought. Some (including the author) think that a moderate flow gives the Falls character. It defines the edges, increases the definition of the drop, and reveals more of the gorge below (including the rock piles below the American Falls).
Others feel that the Falls in the diverted state is just “unnatural” and that they could be larger, louder, and more powerful if reverted back to their original state. Although this is an interesting concept, realizing it would not only eliminate the region’s largest supply of power, but also put the current infrastructure around the Falls and the Falls themselves in jeopardy of destruction by swift erosion. Those are giant roadblocks for returning the Falls to its original grandeur, but perhaps it wouldn’t be unthinkable to crank up the spigot a few hours or days a year to give tourists another reason to visit the Falls.
Niagara Falls Books / Media
Writing / Photography