One of the largest wind farms in Australia - which will power nearly 500,000 homes - will be built in the central west of NSW.

The NSW government approved the $643 million Liverpool Range wind farm on Tuesday, saying it will deliver 800 jobs to the upper Hunter and central west communities.

The farm, which spans 36km from north to south and 20km east to west, will generate almost one gigawatt of power, NSW Planning Minister Anthony Roberts said in a statement on Tuesday.

Community concerns about the project were raised during the consultation period and included issues such as noise, visual impacts, biodiversity and traffic.

Mr Roberts said changes have been made to the project, improving its outcome on the community and environment.

The changes include a reduction in the number of turbines to 272, reducing the number of proposed substations from six to four and Epuron, the company developing the farm, has agreed to upgrade local roads around the project.