Rainpower’s delivery comprises a complete replacement of the plant’s electromechanical equipment, mainly consisting of four reversible pump turbines with a head of 284 to 395m, and maximum performance of 41MW, and one Francis turbine with a head of 270 to 390m and maximum performance of 27MW. The deliveries are complete with inlet and outlet valves and oil pressure units.

Due to the extreme variation in head range, the contract also includes model tests of two different pump turbine runners in Rainpower’s laboratories in Trondheim. The total project will be carried out by a consortium of Rainpower and alstom Switzerland, with Alstom supplying the generators/motors and the inlet valves for the pump turbines.

The average annual production of the Robiei power plant is 106GWh. The original equipment was commissioned in 1970, and the components of the power station had to be transported to Robiei by a cable car with a maximum carrying capacity of 19.4 tons. This limitation had an impact on the design of the electric machines. Rotors, stators and transformers will be assembled on site.

Rainpower is currently also delivering a complete upgrade of the Bavona power plant for the same customer. This delivery consists of two twin horizontal Pelton turbines, which are among the largest of their kind in the world. The power station will be commissioned in September 2010.