Sorensen Provides Hydro Turbine Control Systems to Westfield, Mass.
The City of Westfield, MA, chose Sorensen Systems as the Hydroturbine System Vendor for the Granville Pipeline Project in Southwick, MA. Sorensen Systems had the responsibility for the entire process. The process involved several steps. Which started with creating a packaged hydropower turbine and generator system. Then designing the necessary electrical controls and instrumentation. This project was part of a broader pipeline replacement initiative to replace the aging existing pipeline. An essential element of this endeavor was the installation of a new Hydroturbine capable of generating 37 kW.
Conduit Energy Recovery
Conduit energy recovery projects are a vital aspect of Sorensen System’s capabilities. There are over 600 public water systems in Massachusetts which make conduit energy recovery a valuable solution. The Granville Pipeline project consists of several components, including a skid-mounted turbine/generator, a hydraulically operated turbine isolation valve, a hydraulic power unit, and a turbine generator control panel. Additionally, there is a remote OIT display panel situated in the Hydroturbine room.
Hydro generation at public water systems and publicly owned treatment plants offers significant advantages over traditional hydropower projects for several reasons. First, the system already exists and doesn’t require construction from the ground up. This allows for the application of conduit exemptions, streamlining the permitting process. Second, the energy generated has an average value approximately 50 percent lower than the typical rate for similar treatment facilities. Lastly, conduit hydropower facilities remain unaffected by the hydrologic cycle.The flow depends on plant operation and demand. This cuts down on unpredictable periods of low generation.
System Design Specifications
The turbine/generator had a design for skid mounting. It featured a 37 kW rated horizontal turbine with coupling and guard. The system incorporated a six-inch Class 125 flanged turbine interconnection spool assembly, along with turbine inlet and outlet pressure transducers. Additionally, it included a Marathon Electric induction generator, which had specifications of 37 kW, 480 VAC, 3PH, 60Hz, and a speed of 1200 RPM, and it was of the open drip-proof type.
The system comprised a hydraulically operated turbine isolation valve, which featured a six-inch AWWA C504 Class 125 rubber-seated butterfly valve with a cast iron body, ductile iron disc, stainless steel disc edge, stainless steel shaft, and a hydraulic-operated spring-closing rotary actuator. The hydraulic power unit was self-contained and included a control valve assembly. Additionally, the turbine generator control panel incorporated an Allen Bradley PLC-based control system, control power circuit breakers, 24 VDC power supplies, an Ethernet switch for interfacing with the existing SCADA system, control switches, and a multifunction protection relay.
Operations & Maintenance Costs
In 2011, tropical storm Irene caused the collapse of the Granville spillway and dam, resulting in damage that amounted to nearly $3 million. The replacement of the pipeline and the installation of the Hydroturbine system also incurred nearly $3 million in expenses. Newspapers reported predictions of a 50 to 70 percent increase in water rates for Westfield, MA, within the next five years, as the total estimated costs could reach $10 million. The significance of all efforts to reduce operating costs for water treatment plant operations through conduit energy recovery grows increasingly important every day.