Submissions for an online questionnaire only will now be accepted until 22 December 2014. The deadline for postal responses was 19 November.
RWE said the extension to the deadline was due to "a number or requests" about the questionnaire, part of the statutory consultation of the electrical system. RWE also admitted to "a technical issue" on the website.
RWE Innogy UK's project manager for Triton Knoll, Jacob Hain, said, "We want to ensure all those who wish to respond to the consultation are given the chance to do so."
Consultation on the electrical system began in October. It covers the 60-kilometre onshore cable system.
The network will connect the project from where the transmission cable makes landfall at Anderby Creek, Lincolnshire, east England, to the national grid connection at Bicker Fen.
In August, RWE withdrew an application with regulator Ofgem to allow access to private land to survey the cable route.
The proposed route remains unchanged in the consultation despite RWE being unable to access the land for surveying.