The New York Power Authority (NYPA) marked the completion of a nearly four-year overhaul of its Blenheim-Gilboa (B-G) Pumped Storage Power Project in the northern Catskills at an event June 10, where NYPA President and CEO Richard M. Kessel was joined by state and local officials in highlighting the milestone. NYPA's Life Extension and Modernization (LEM) effort will improve the reliability of critical electricity infrastructure and increase the NYPA's ability to help meet the long-term energy needs of the state.

“The on-time and on-budget completion of the Life Extension and Modernization Program at Blenheim-Gilboa is a hallmark of achievement for all of those who've been involved with the nearly four-year initiative, which secures the future of this special hydroelectric facility for decades to come,” Kessel said. “B-G's value to New York state is especially apparent during the air-conditioning season when the margins between available electricity supplies and power consumption narrow the most, and market electricity costs tend to rise. For that reason, the completion of the project's refurbishing ahead of the peak-demand months is good news for the state's electric power system and ratepayers, and something to celebrate.”

On May 22, the NYPA returned to service the last of B-G's four pump-turbine generating units to undergo replacement as part of the more than US$135 million upgrade of the 37-year-old facility, which recycles water between lower and upper reservoirs to generate power when it is most needed, generally in the late afternoon or early evening. The more efficient, modern units allow the pumped-storage project to produce additional power from the falling water from the upper reservoir on Brown Mountain, with the total capacity of the facility increased by 120 MW, or 11.5%, to 1160 MW.

“Our maximizing of B-G's efficiency — and its ability to generate more power from the same amount of water — contributes to the overall reliability and flexibility of the state's electric power system,” said Michael J. Townsend, NYPA chairman. “This has been a vital initiative for enhancing the project's capability for harnessing the stored water from the project's upper reservoir to produce economical power during the times of peak demand. The Life Extension and Modernization Program also reflects the priority the Power Authority has long given to being a good steward of its hydroelectric resources, which account for nearly 80% of its statewide power generation.”

NYPA began the LEM at Blenheim-Gilboa in September 2006 when the first of the four pump-turbine generating units was taken out of service for refurbishing. The process was repeated three times, in the fall of 2007, 2008 and 2009, with each unit returned to service by the following summer with an increase in maximum capacity from 260 MW to 290 MW per unit. (While the physical work for the LEM began in 2006, the engineering and procurement for the initiative commenced in 2003.)

The LEM program marked the first major overhaul at B-G since it went into service in July 1973 at its Schoharie Creek site in the towns of Blenheim and Gilboa in Schoharie County, about 40 miles (64 km) southwest of Albany. The Federal Energy Regulatory Commission, the regulatory organization responsible for licensing the nation's nonfederal hydroelectric projects, authorized the work.

The pumped-storage project is designed to operate like a giant storage battery. At times of peak demand, hundreds of thousands of gallons of water are released from B-G's upper reservoir, plunging 1200 ft (366 m) through a 28-ft (8.5-m)-diameter vertical shaft within Brown Mountain. The water drives the project's four turbine-generators before flowing into the lower reservoir on Schoharie Creek, just below the powerhouse, where the equipment is contained.

At night and on weekends, when demand is lower, the water is pumped back to the upper reservoir using economical electricity from the most efficient thermal generating units.

Senator James L. Seward said, “Blenheim-Gilboa has always been an innovative, cost-effective and environmentally sound facility from its birth in the 1970s to today. Now, with the completion of the Life Extension and Modernization project, Blenheim-Gilboa will continue to meet the electrical demands of New Yorkers for years to come, providing low- cost power to residents and businesses in a safe and reliable manner.”

For more information, visit