Big Allis, formally known as Ravenswood No. 3, is a giant electric power generator originally commissioned by Consolidated Edison Company (ConEd) and built by the Allis-Chalmers Corporation in 1965. Currently owned by Transcanada Corp., it is located on 36th Avenue and Vernon Boulevard in western Queens, New York. Its main fuel is natural gas.
During 1963, Allis-Chalmers announced that ConEd had ordered the "world’s first MILLION-KILOWATT unit...big enough to serve 3,000,000 people." This sheer scale helped the plant become popularly known as "Big Allis". During the 1965 black-out the bearings of the Allis-Chalmers Turbine were damaged. The lube oil pumps were hooked up to the electrical grid, thus shutting them down during the blackout and causing bearing damage.
At the time of its installation, it was the world's largest steam energy generating facility. It is located on the Ravenswood site, consisting of Units 1, 2, 3 and 4, as well as several small Gas Turbines (GTs), and an oil depot. The site overall produces about 2,500 MW, or approximately 20% of New York City's current energy consumption. It was retrofitted to burn some coal and oil in 1983. In 2011, Big Allis burned 97% natural gas, 2% coal and 1% oil (used as backup fuels).
The Ravenswood, Queens site also includes a steam generation plant consisting of four Babcock & Wilcox boilers, commonly known as "The A House", currently owned and run by Con Edison. The plant helps in the supply of steam to the Manhattan steam system when needed, via the Ravenswood tunnel crossing under the East River.
Ravenswood was owned by Con Ed from the time it was built until 1999, when due to deregulation, Con Ed was forced to sell its in-city generating capacity. KeySpan bought the site for US$600 million. In 2007, KeySpan merged with National Grid. Because of the possibility to influence in-city electrical costs due to National Grid's significant upstate electrical distribution, the New York State Public Service Commission forced National Grid to sell the site. In 2008, TransCanada Corp, based in Calgary, Alberta, Canada, bought the site for US$2.9 billion.
- Massey, Daniel (June 23, 2009). "Labor fight could unplug Queens power plant". Crain's New York Business. Archived from the original on 26 June 2009. Retrieved 2009-08-14.
- Con Ed Preparaing Queens Plant for Coal Use, By PETER KIHSS, The New York Times, August 1, 1982, Sunday
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