Bulb Hydro Turbine

Bulb Hydro Turbine

With more than 300 bulb units installed worldwide, GE brings expertise in design, manufacturing, installation, commissioning and management of complex bulb projects, for a wide range of environmental conditions.

Product Features

The term "Bulb" describes the shape of the upstream watertight casing which contains a generator located on a horizontal axis.


Runner configuration is crucial to optimizing a turbine unit for each individual project. GE can help to optimize each unit for the peak performance within its environment. 

Shaft Line and Bearings

Two radial bearings ensure the stability of the horizontal shaft line while the turbine is in operation.

Advanced Generator Design

GE engineers our turbines to ensure reliability in a range of operating environments and circumstances. They have been developed to handle conditions such as roundness and air gap concentricity, and have been successfully applied in bulb units up to 60 MVA.

Downstream Gate

A draft tube gate ensures a reliable protective system for bulb units, providing:

  • Protection against runaway conditions
  • Downstream isolation during unit dewatering
  • Sluice operation


Efficient Development and Construction

To ensure a fast and streamlined construction, we've developed a sreamlined process in which the following systems are assembled simultaneously:

  • Rotor, stator, and bulb nose in the upstream pit.
  • Runner hub, blades, turbine cone, and runner discharge in the downstream pit.
  • Turbine accessories.


Reference Projects

Hundreds of GE Bulb units are now in operation around the world, including more than 35 large units commissioned in China alone over the last ten years. 

Jirau and Santo Antonio (Brazil), 2012/2013

10 x 76,65 MW and 19 x 75,5 MW

Chang Zhou and Qiao Gong (China), 2008

3 x 42 MW - Head: 10 m. and 4 x 57 MW - Head: 14 m.

Ourhinos (Brazil), 2004

3 x 15 MW - Head: 11 m.

Paldang (South Korea), 1973

4 x 21 MW - Head: 12 m.

St Egrève (France), 1990

2 x 23 MW turbine + generator - Head: 12 m.

Rock Island (USA), 1978

8 x 51 MW - Head: 12 m.

La Rance (France), 1966

4 x 10 MW - Head: 11 m.


  • 40% increase in unit output compared to five years ago
  • Smaller reservoirs which reduce environmental footprint

Let Us Help You

Want to get the most out of your renewable energy assets? Reach out to your GE team to start the conversation.

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