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Hydropower is electricity produced from flowing water. Hydropower produces approximately 7% of U.S. energy (19% of world energy) and accounts for 45% of total renewable energy in the U.S. Newer technologies harness energy in ocean tides, waves, and currents.

Hydroelectric level and flow applications

  • SURGE TANK: The main function of a surge tank is to control pressure variations due to rapid changes in the velocity of water. When the power turbine is running at a steady load, there are no surges in the flow of water since the quantity of water flowing through the conduit is sufficient to meet the turbine’s requirements. When turbine load decreases, a governor closes the gates of the turbine to reduce water supply. The water is routed for storage in the surge tank—an action that prevents the conduit from bursting. When  turbine load increases, additional water is drawn from the surge tank to meet the increased demand. A surge tank’s internal diameter may range from a few feet to several dozen feet. The tank relies on a level sensor to determine whether or not water stored in the tank should  be removed.
  • PUMP PROTECTION: Flow Switches protect pumps from damage due to leaks or if a valve is accidentally closed downstream. A switch will actuate an alarm and shut down the pump when flow drops below the minimum rate.