The first and only TBM to ever operate in the Faroes, a 3.35m diameter Robbins Main Beam machine, is being put to use once again extending a hydropower project with an 8.4km collector tunnel on the island of Eysturoy.
The Robbins TBM, for Danish and Faroese contractors MT Hojgaard and J&K Petersen, was originally purchased in 1984 and has since excavated about 25km of tunnel for the Eidi Hydropower Plant. The latest project, known as Eidi II, is part of a new green energy initiative by the utility agency for the Faroes: Streymoy, Eysturoy and Vágoy (SEV). The tunnel will collect water from 25 streams, increasing the annual capacity of the plant from about 43GWh to about 60GWh.
Prior to startup, the SEV-owned machine underwent some refurbishment to the gearboxes, main bearing, lube system, and hydraulic hoses. “Prior to starting up this project, we contacted Robbins for an assessment. We got an immediate response, and two men were sent to inspect the machine. They concluded it was in good condition following the upgrades,” said Anders Nedergaard-Hansen, Head of the Power Production Department for SEV. Robbins is also providing key spare components including the cutterhead, grippers, hydraulic, and lube systems. Robbins Field Service personnel have also been provided for the project duration.
By October 2010, the machine had excavated several hundred meters of tunnel in basalt rock with no problems. Tunneling at Eidi II is expected to be complete in March 2013, and the newly expanded plant commissioned later that year.
The Faroes, a collection of 18 windswept islands in the North Atlantic, are home to nearly 48,000 people. Situated between Iceland and Norway, the mountainous islands receive an average of 250 days of rainfall annually, creating significant runoff. These features make the islands ideal for small hydropower plants utilizing collector tunnels to transport rainwater.