The companies are competing to connect the Gwynt y Mor, Lincs and London Array Phase 1 wind farms, which have a total generating capacity of over 1.4GW.
The winning bidders will own and operate the power links for the next 20 years.
The eight companies that have qualified to bid include Balfour Beatty Capital, Blue Transmission, Cheung Kong Infrastructure, Green Energy Transmission, Mitsubishi Corp, National Grid Offshore, Transmission Capital Partners and Ventran Consortium.
