Electricity: Enormous Homegrown Power Downtown
Who cares where electricity comes from; just plug in the TV, DVD player and coffee maker; sit down and enjoy life?
I must confess electricity generation never crossed my mind since I studied high school physics 50 years ago. Recently, a random thought challenged me: the mystery of magnetism.
Mr. Pagett, the Southwestern High School physics teacher, gave me an outdated physics textbook so I could study magnetism. I learned magnets are the required component to generate electricity. To learn first hand how electricity is generated, I was taken on a tour of the Jamestown Board of Public Utilities (BPU) Power Plant last week by Dave Gustafson, the electric and gas resource manager, also accompanied by Becky Robbins, the communications coordinator.
If you are curious, read on for an explanation on how electricity is generated locally in the power plant inside the huge brick building on Steele Street. A simple lesson of physics teaches an electric current is generated in a wire placed near a moving magnetic; an electric generator utilizes this principle.
In effect a moving magnetic pushes electrons through a wire to generate an electric current. If the magnet is moved rapidly past miles and miles of wire in multiple coils, strong electric currents are generated. The generator at the Jamestown BPU uses a solid cylindrical metal magnet 12 feet long and 2 feet in diameter spinning at 3,600 rpm (revolutions per minute) inside coiled wire.
The moving magnetic “pushes” electrons (electricity) through the wires into large cables, which conduct the current at 13,800 volts out of the building to businesses and residences locally. Spinning the huge heavy magnet rapidly is the complicated component of electrical generation.
In the recent past, the Jamestown power plant burned coal to boil water, creating steam under pressure similar to a home pressure cooker. The steam was directed onto blades of a large fan called a turbine attached to a drive shaft or rotor. The force of the stream spun the turbine attached to the magnet by the drive shaft at 3,600 rpm, thereby spinning the huge magnet inside the surrounding wire coils.
Today, in Jamestown, natural gas is burned instead of more expensive coal to produce steam, and a new gas turbine installed 10 years ago functions like a reverse jet engine, eliminating the need to produce steam.
Gustafson states, “The BPU has determined due to the implementation of new environmental regulations that affect the operation of the older coal fired equipment, it is unlikely the utility will switch back to relying upon coal as a major fuel source.”
The newer gas turbine generator uses 2001 technology, creating 45 percent efficiency, while the steam turbine built with 1968 technology has only 30 percent efficiency. The Jamestown power plant currently generates at peak production, 60 megawatts of power with the combined gas-fueled steam generator and separate gas turbine generator.
A coal-fueled backup generator for emergency shut down of the two existing generators is available. By comparison, the Niagara Power Project generates 3,600 megawatts per day, while the Dunkirk power plant generates 500 megawatts.
The electrical peak requirement for residences and businesses on a zero degree Fahrenheit day in Jamestown is 100 megawatts. Supplemental electricity is purchased from other power generators in the state like the Niagara Power Project, which uses hydro power instead if steam to turn the magnets. Jamestown receives an allotment of 72 megawatts daily from Niagara Falls if needed.
One kilowatt hour (1,000 watts) of electricity will run a television for nine hours and a 40 watt light bulb for 20 hours.
During a tour of the Jamestown BPU, Gustafson told me, “All the pipes, cables, gauges, conduits, turbines and boilers one sees exist to keep the magnets turning.”
Wherever and whenever electricity is generated, the mysterious magnet must be present. I will leave with a fact to ponder. The electric motor in an electric cake mix beater functions in reverse from an electric generator; electricity into wire coils in the appliance create a magnetic field which spins another magnet which turns a rotor connected to the beaters.