GMP - Vergennes Turbine Rehabilitation

Project Name: Vergennes #9 Hydroelectric Station

Summary: Overhaul of mechanical and electrical equipment

Client: Green Mountain Power

Project Location: Vergennes, VT

Project Size: 3 MW

Services Provided:

•  Hydro Feasibility & Planning
•  Hydro Energy Analysis
•  Hydro Facility and
    Equipment Condition Assessment
•  Penstock Inspection and Design
•  Electric Power & Interconnection
    Systems Design
•  Gates & Water Control Design
•  Turbine Procurement Assistance
    and Installation Design
•  Construction Services
•  FERC Compliance Management and
•  Federal, State and Local
•  Agency Consultation

Project Timeframe: 1993 - 2011

Relationship with Client: Since 1980’s

Client Needs:
Green Mountain Power (GMP) needed study and design services to automate and upgrade its Vergennes #9 Hydroelectric Station built in 1912 which had become mechanically unreliable and had a limited remaining service life. Also this station’s FERC license to expire in 1997.
Kleinschmidt Solution:
Kleinschmidt performed an initial assessment and feasibility study to evaluate upgrading the station prior to GMP beginning the FERC relicense process. After GMP received a new FERC license, Kleinschmidt upgrade services addressed various compliance articles including design and replacement of head gates with a new monorail frame, design and installation of new automation equipment including PLC logic development and software programming, and compliance filings related to recreation access and revision of project boundary mapping. Kleinschmidt assisted GMP with feasibility studies, equipment procurement, facility retrofitting and installation construction services for replacing the two new 1.1 MW hydroelectric turbines. In addition, Kleinschmidt designed a new compressed air braking system and customized the new turbines with a spring operated fail-safe wicket gate closing system if the hydraulic system were to fail. In the final redevelopment phase, Kleinschmidt designed a complete new replacement intake which cost effectively used multi-strand and solid bar rock anchors for stability, and two 9 foot diameter by 225 foot long ring girder supported steel penstocks with compound angles. Kleinschmidt provided assistance the necessary permits including FERC amendments as well as construction services throughout each phase of the redevelopment.
Client Benefits:
Through the various station upgrades to this facility, Kleinschmidt incorporated adaptive design features that allowed GMP to met the various FERC license mandates, reduce labor costs, allow control through central dispatch to better utilize river flows for increased revenue, eliminated unnecessary costs, restored station reliability, and increase the station capacity by 25%.