Genesis Energy has applied for resource consents to build a wind farm with up to 286 turbines in northern Wairarapa.
The Castle Hill project would have a potential nominal capacity of up to 860 megawatts of electricity, equivalent to the amount used by 370,000 average households, Genesis said.
The turbines, with a maximum height of 155m, would be within a "turbine corridor'' of about 3144ha in a total site covering 30,000ha, 15km west of the Wairarapa coast north of Castlepoint.
The Castle Hill site had an excellent wind resource, along with suitable topography for access and construction, and was in a remote area that was relatively sparsely populated, Genesis said.
Six small rural settlements were in or around the site, with a combined population of about 500 in 110 households in 2006.
An economic assessment by Berl said the cost of getting the wind farm up and running would be around $1.68 billion spent over five to six years. Once construction was finished, operational costs were expected to be $39 million a year.