The First Flight wind consortium, comprised of Dong Energy, RES and B9 Energy, said it would reduce the size of the project to between 300MW and 400MW to reduce the impact to a minimum.
Following consultation with stakeholders, First Flight Wind director Michael Harper said the project would now attempt to avoid the Warrenpoint-Heysham shipping route and reduce the impact on fishing grounds for langoustine.
The planned site is located eight kilometres off the County Down coast in the Irish Sea and is due to be operational by 2020 if it obtains all necessary consents.
First Flight Wind was selected to develop the site by the Crown Estate, which is responsible for the waters around the UK, in 2012.