Sunday, February 14, 2010
Where will the interisland cables from HECO’s Big Wind project come ashore?
By Henry Curtis
Hui o Ko‘olaupoko (HOK) is sponsoring a Talk Story Session with HECO and DBEDT on Wednesday February 17, 2010 from 6:30-8pm at 146 Hekili Street room 202.
The proposal to develop Wind Farms on Molokai and Lanai and ship the electricity to Oahu is very complex.
Castle & Cooke proposed a 400 megawatt (MW) wind farm on Lanai. First Wind proposed a 400 MW wind farm on Molokai. The HECO – Castle & Cooke - First Wind Agreement sought to bypass legal arguments over whom HECO would get the wind energy from. Each company will provide 200 MW unless one system is not built, and then the other company can build a 400 MW wind farm.
The Inter-Island Cable must be able to handle either contingency. How many lines would have to be built underwater?
A few years ago HECO said that 400 MW of power provided by three generators in Campbell Industrial Park were vulnerable due to a lack of sufficient transmission lines:
“The HECO system is currently vulnerable to loss of the entire CIP generation since there are only two transmission paths available to export power from CIP. Having only two lines to export power makes the CIP generation the least robust of HECO’s major generating nodes. ...generating capacity in CIP is similar to that of HECO’s Kahe and Waiau power plants, but with many fewer lines available to export power. If one of the two available CIP connecting lines is out of service and a fault or failure should occur on the remaining line, all CIP generation would become disconnected from the HECO system.” (Hawaiian Electric Company, Inc. (HECO): Final Environmental Impact Statement for the Campbell Industrial Park (CIP) Generation Station (CT-1) & Transmission Additions (July 21, 2006), p. 1-34)
Thus Oahu would need to be connected to Lanai and Molokai using three transmission lines following two different routes. For reliability and redundancy purposes, the transmission lines would probable come ashore in Iwilei and at the Kaneohe Marine Air Corps Station. The latter is five miles from the Oahu transmission grid, so a high voltage transmission line would need to be built in Ko‘olaupoko along the H-3.