Double regulation system allows high performance over a large range of head and discharge
Alstom's Kaplan turbines in operation cover low head applications ranging from about 15 to 50 meters, and outputs up to 130 MW.
Thanks to their double regulation they provide high efficiency over a broad range of head and discharge/output.
Compared to Bulbs, their vertical configuration allows larger runner diameters (above 10 m) permitting to increase the unit power and thus minimising the number of units
Kaplan turbines have the same challenge as Bulb turbines: both are often installed on large rivers where fish ladders allow the fish to migrate upstream for spawning. Our Kaplan turbines have a "fish friendly“ design improving the survival of this species while migrating.
Another key environmental concern is accidental water pollution though oil spill. To prevent this, we are experienced with water-lubricated bearings and water filled hubs.
In order to increase the environmental friendliness of our Kaplan turbines we have developed oil-free hubs where the oil traditionally filling the hub has been replaced by water and all bushes are made of self lubricating material. This eliminates the risk of oil leakage in the river, which is the most important pollution risk.
Fish Friendly turbines
Power dams impede migratory fish movements. The downstream migrating fishes often pass through the turbines exposing juvenile salmons and other species of fish to physical stress, injury or death. Extensive studies have been performed by Alstom to define biological design criteria of turbines in order to dramatically reduce fish injuries.
- Brillant (Canada), 2006 - 1 x 120 MW - Head: 30 m.
- Grand Mère (Canada), 2004 - 3 x 77 MW - Head: 24 m.
- Qing Shan Dian (China), 1998 - 2 x 20 MW - Head: 29 m.
- Terminus Dam (USA), 1995 - 1 x 17 MW - Head: 52 m.
- Porto Primavera (Brazil), 1999-2003 - 18 x 101 MW - Head: 10 m.
- Buyo (Ivory Coast), 1976 - 3 x 45 MW - Head: 27 m.