Hydroelectricity

Since 1985, the City of Boulder has run a hydroelectric program to turn water power into electricity, generate revenue, and provide sustainable, non-polluting electricity.

Flowing water spins a turbine, which in turn spins an electrical generator to produce electricity.

Boulder's eight hydroelectric power plants (one purchased and seven constructed over the last 20 years) convert the energy in flowing water into electricity. This energy exists in water because of large changes in elevation between the city's diversion points from streams and the delivery points for treated water in the city. This energy would be wasted if not converted to electricity. No fossil fuels are consumed and nothing is emitted in the conversion process. 

The seven constructed power plants were installed on water supply pipelines that were already used to provide water to the city.  No new dams or overhead transmission lines - two of the negative impacts often associated with hydroelectric power - were built.

Amount of Renewable Energy Produced

In 2008, the city's hydroelectric facilities generated about 42 million kilo-watt-hours (kWh) of electricity. Each year, the hydro generation provides sufficient power to serve 7,500 homes. Since the first hydro went into service in 1985, more than 426 million kWh have been generated and a total of $20.2 million in revenue have been produced for the city.  

Each kWh of electricity generate at a coal-fired plant requires the consumption of about one pound of coal and results in the release of two pounds of carbon dioxide - a greenhouse gas - into the atmosphere. Boulder's renewable energy production displaces the need to burn 20,500 tons of coal each year and has prevented the burning of 213,000 tons of coal since 1985.

The electricity generated by Boulder's hydros is sold to Xcel Energy for delivery to their customers. Hydroelectric revenues for the city are about $2 million each year.

Specifics about Boulder's hydros:

The city's untreated water generates electricity at three hydro plants above the Betasso Water Treatment Facility, located in the foothills west of Boulder. After the water is treated, it generates additional electricity at four hydro plants below Betasso. These turbine-generators were installed adjacent to pressure reducing valves that are necessary for proper water supply operations, but waste this source of energy. Electricity is also generated from the water returned to Boulder Creek through a hydro plant owned by the city.

The city's eight hydroelectric generators have a combined rated capacity of 20.1 megawatt-hours (MWh). The generation capacity for each plant depends on available flow, turbine flow limits, gross head, head loss and equipment efficiency. Available flow is set by the municipal water supply in Boulder. Much of the generation potential in the Boulder water system results from high demand during the summer months.

Advantages of Hydroelectricity

• Hydroelectricity generation is environmentally beneficial because it doesn't produce any greenhouse gases and is made by water, which is a renewable resource itself.
• Hydroelectric power is reliable because it only depends on gravity, water to drive simple machinery.
• Using water to turn a turbine captures twice as much of the available energy as burning fuel to turn a turbine.
  

Last Updated on Monday, 18 May 2009 04:02