The overall LEM programme is scheduled for completion in 2013, with refurbishment of the 13th turbine, which began immediately after the completion of the 12th, expected to be completed by August of this year.
The Power Authority began the St. Lawrence LEM program in 1998 to replace or renovate the original major generating equipment in the power project and improve the overall performance flexibility and efficiency of the facility, which has operated continuously since 1958.
The work has required a highly coordinated effort involving nine major component manufacturers in achieving numerous installation milestones. Among the most significant activities has been the disassembly and removal of the turbines, the major component of the turbine-generator units, and the renovation of their turbine-pit locations to facilitate the installation of the refurbished units.
alstom Hydro was awarded two independent contracts – one in 1998 and the other in 2004 – to manufacture all 16 replacement turbines. The turbines are of two different designs, corresponding with the original equipment manufactured by Baldwin Lima Hamilton (BLH) and Allis Chalmers (AC).
At the time of St. Lawrence-FDR’s construction more than 50 years ago, no single manufacturer could meet the ambitious schedule for supplying the turbines. The responsibility was evenly divided between BLH and AC. Since 2007, the LEM program has centered on the AC turbines, following the replacement of the eight BLH units.
Among the design advances in the replacement turbines is a more efficient shape for harnessing available water from the St. Lawrence River to generate power. The new turbines also use stainless steel instead of the carbon steel composite of the original equipment. Stainless steel is more resistant to corrosion and requires less maintenance, which will contribute to extending the life of the hydroelectric project.
Other elements of the LEM have included generator rewinding, installation of new switchgear, replacement transformers, and modernization of protection and control systems.