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Hydropower in New York

A Workhorse Renewable Energy Technology

Inside view of a giant turbine
This giant turbine is one of 16
that together can generate more
than 900,000 kilowatts [900 MW]
of electricity at the St. Lawrence-
FDR power project. Operated by
the New York Power Authority,
the project straddles the St.
Lawrence River with a run-of-
river hydroelectric station shared
by New York and Ontario, Canada.
(Photo courtesy of New York
Power Authority)

New York is the largest hydroelectric power producer east of the Rocky Mountains and is fourth in the nation in the generation of electricity from hydropower. More than 300 hydroelectric generating stations - some very small, a few very large and many in between -- connect to New York's electric grid. Hydro plants typically meet at least 17 percent of the state's total electricity demand with renewable, clean and inexpensive power.

In a hydroelectric power plant, turbines that are run by moving water generate electricity with no greenhouse gas emissions and little pollution of any kind. DEC works with other New York State agencies and the Federal Energy Regulatory Commission to assess and mitigate possible effects on aquatic life from turbines or power dams.

Hydropower has provided electricity to New York since the first generating plant opened at Niagara Falls more than a century ago. Reliable and able to quickly increase or decrease power output, hydro generation helps to stabilize the electric grid and support less-flexible sources of renewable energy. Some facilities even can store energy for later use.

Picture of partial water wheel against stone wall with water below
Early New Yorkers harvested energy
from falling water to directly drive mills
that ground grain and sawed timber.
Mature water power technology
enabled even small streams to run
entire factories - but only if they were
located where the stream's course
dropped quickly to a lower level. Today,
hydroelectricity carries the energy of
flowing water far from stream banks,
and new turbine technologies can harvest
energy from tides and fast streams
even without a large elevation drop.

Hydropower is among the most cost effective of all electricity sources. Because its "fuel" - flowing water - is local and is replenished whenever it rains or snows, the price of hydroelectricity usually remains stable even as markets for other fuels fluctuate.

New York has strategically pursued policies designed to develop hydropower (both conventional and newer hydrokinetic technologies) as part of a diverse portfolio of renewable energy resources. To support economic development and jobs, the Recharge New York program distributes low-cost hydropower to businesses in exchange for commitments to create and retain jobs in the state.

Hydropower Technologies: Large and Small, Old and New

Hydropower generation converts the energy of moving water into electricity. A wide choice of technologies and scales gives hydro the ability to meet both large centralized urban electricity needs and decentralized rural needs.

Conventional hydroelectric technologies

In conventional hydroelectric plants, the turbines that generate electricity are turned by falling water. Some conventional plants store water in reservoirs behind dams, controlling its release to generate predictable electric power (and often providing drinking water, irrigation, flood control or navigation as well). Other plants (called "run-of-river" facilities) simply take advantage of an elevation drop in free-flowing water, incorporating little or no water storage.

Cohoes hydroelectric plant with penstocks on left of picture and Cohoes Falls in the top right
The 38-megawatt School Street
hydroelectric plant in Cohoes is
owned by a private company
that operates several small
hydro facilities in New York.
Water diverted from the
Mohawk River falls 90 feet
through five large pipes to turn
turbines that generate electricity.
The water then flows back into
the river below Cohoes Falls.
(Photo courtesy Times Union)

Today, conventional hydropower stations generate nearly nine-tenths of all the renewable energy produced in New York. The New York Power Authority (NYPA) owns the two biggest plants, the Niagara River and St. Lawrence Power Projects. These two publicly-owned plants contribute far and away the largest share of New York's total hydroelectricity generation.

The remainder of New York's hydroelectricity comes from numerous small plants, a few owned by NYPA or municipal governments, some by institutions or industries, and many others by private companies whose business is selling electricity to the grid. A 2011 enumeration found a total of 345 conventional hydropower station units operating in the state.

Hydrokinetic systems

Unlike conventional hydropower facilities, which require either a dam or a stream elevation drop to produce energy, newer in-stream or hydrokinetic systems place turbines below the surface of moving water -- in tidal flows, rivers, canals and even wastewater treatment plants.

Tidal in-stream hydrokinetic systems use pivoting turbines that capture energy for the majority of the day regardless of which way the tide flows. These systems are most productive in strong, fast currents, such as are found at the entrances to bays or in "narrows" between land masses. Inland hydrokinetic projects, on the other hand, use fixed turbines to provide round-the-clock electricity whenever streams are flowing.

While hydrokinetic energy is not yet operating at commercial scale, research, development, and demonstration are well along. In New York, new tidal

B;ie turbine being lowered into river with yellow straps from barge. Barge on left side with workers watching
The Roosevelt Island Tidal Energy Project,
located in New York City, holds the world's
first commercial license for tidal power
from its grid-connected array of turbines in
New York City's East River. Initiated in 2002,
the project completed prototype and
six-turbine demonstration phases. (Photo courtesy of Verdant Power)

kinetic hydropower technology installed in New York City's East River was recently connected to the electric grid, and a proposal now under development would test the feasibility of hydrokinetic generation in the Niagara River.

Pumped storage systems

Pumped storage hydroelectricity is the largest-capacity form of grid energy storage currently available. Pumped-storage units located at Blenheim-Gilboa and Niagara Falls-Lewiston use inexpensive off-peak electricity to pump water to a high elevation, from which it is released to generate power during times of peak demand. Pumped storage facilities use more power for pumping than they generate during operation, but the electricity they produce helps to balance power grid loads and reduce the total cost of electric power.

The Future of Hydropower in New York

While other forms of renewable energy, such as wind and solar, have greater potential for future expansion, hydro is expected to hold its own or grow slightly as a mainstay of renewable power generation in New York.

Upgrades of existing plants and adoption of high-efficiency small hydro technologies are enabling important incremental increases in the state's hydroelectric generating capacity. In future years New York could see a significant increase in hydropower from coastline installations if wave conversion or tidal in-stream power technologies prove technically and economically feasible.

Repowering existing generation facilities

Installation of high-efficiency turbines, improvements to power station infrastructure and other upgrades can significantly increase the electricity output of older hydroelectric plants. A recent study of renewable energy in New York found upgrading existing hydropower plants to be one of the least expensive ways to increase renewable electricity generation.

Aerial view of Higley Dam surrounded by green trees and the Dam
The Higley hydroelectric station, located on
Lower Raquette River in St. Lawrence County,
underwent a major repowering in 2003-04. A
new water intake, penstocks, powerhouse
and high efficiency generation equipment
increased the plant's output from approximately
4.5 MW to 6.2 MW, a gain large enough to
to power more than 1,700 average homes.
(Photo courtesy of NYSERDA)

With support from the state's Renewable Portfolio Standard, upgrades to 25 existing hydropower generation stations have been completed or are underway in New York. Renewable Portfolio Standard funding is available for existing plant upgrades and for new low-impact run-of-river facilities up to 30 MW of capacity with no new storage impoundments.

Periodic relicensing of hydropower stations offers opportunities for stakeholders to provide input to license conditions that could include environmental protection and enhancement, economic benefits, and recreational amenities.

Retrofitting non-power dams

Adding generation equipment to existing dams that are now without hydropower is another possibility for increasing New York's total generation capacity with minimal environmental impact. Many existing flood control or water management dams would require only a modest investment in generation equipment to become small hydro generators.

According to the US Department of Energy, hydropower from non-power dams often is found to complement

Neversink Dam with river and mountains in background
New York City is exploring the feasibility of
generating electricity at four dams in the Catskill
Mountains that create reservoirs for the city's
drinking water system. At Neversink Dam (shown)
a valve in the water chamber would be replaced
with a 1.9-foot turbine to create an installed
capacity of up to 5 MW. No changes are
proposed in the water release regime.

other renewable sources and could help to diversify the distribution of hydropower across the state. The US Department of Energy has estimated that New York could develop as much as 295 MW of generating capacity at existing non-power dams.

Distributed hydroelectric generation

Small or low-head hydropower generation could play a role in making New York's power grid more resilient to climate change. When deployed with energy storage and smart grid technologies, locally-sized hydro

Small hydro pipes with small building at top with man standing inf front
Small and mini hydro facilities can be part of
a distributed electric generation system and
provide power for remote areas. They do
not need large dams or reservoirs to generate
power, and emit no greenhouse gases.
(Photo courtesy of Renewable Energy Magazine)

systems can help utilities reduce or manage demand for grid-based electricity, introduce redundancy to back up the system and might be designed to keep power flowing to local users in the event of wider power interruptions. Smart grid technology is needed to facilitate use of small hydro and other renewable resources whose energy output varies with weather conditions or season.

Ocean-based hydropower: a possibility for the future

It is estimated that converting less than one-tenth of one percent of the renewable energy within the oceans into electricity could satisfy today's world demand more than five times over.

With more than 120 miles of Atlantic Ocean coastline, New York could benefit significantly from any technology that generated electricity from any or all forms of seawater energy -- potential, kinetic, thermal or chemical. At this time, two technologies, wave energy conversion and tidal in-stream energy conversion, appear to offer the greatest potential for application in New York.