Running Gear: Two Francis turbines, one synchronous and one induction generator. Total capacity 275kW.
Scope: Complete design/build for one turbine/generator, controls and switchgear for two units, new automatic trash racks.
This utility owned and operated facility was originally built in the early 20th century to supply power to a soapstone quarry. The original powerhouse, built out of the local soapstone, is still in use today. The plant originally had two 200 kW generators, but one unit was sold and removed by a previous owner. The current owner, an electric cooperative, obtained a turbine for a replacement, but needed another generator, and someone to build an integrated system.
PHT was hired to refurbish the turbine, and supply a new draft tube, shaft, lignum vitae guide bearings, belt drive induction generator, wicket operators, switchgear, upgraded controls for both units, and trash racks. Except for the existing turbine and generator, PHT overhauled the entire plant, turning the small and aging facility into a modern, efficient, and productive asset. Through consultation with PHT, the plant owner chose strategic upgrades that allow for the most efficient use of water at a marginal site, as well as increasing the safety and reliability of their equipment.
(Click on an image for a larger view)
Installation of the trashracks was an interesting problem. The site is in a remote, mountainous area, and the best access is by fording the river (at an improved crossing). The location and weight of the racks also prevented a crane from being able to set them. PHT used an excavator to carry each rack across the river, then drive into the canal and set the rack. This worked well – transport from our shop in NC and installation were completed in just one day.