AUGUSTA — A subsidiary of the parent company of Central Maine Power announced today that it plans to bring a natural gas pipeline into Augusta.

Maine Natural Gas, affiliated with CMP owner Iberdrola USA, said it has begun discussions with potential large customers for a natural gas distribution system it is proposing to build from Windsor to Augusta.

The proposed line, if enough large customers commit to using it, would initially serve the east side of Augusta, tapping into an existing natural gas pipeline in Windsor and running along Route 17 to Hospital Street, or Route 9, in Augusta.

It would not be affiliated with Kennebec Valley Gas Co.’s proposed pipeline, which developers are planning to bring natural gas from an existing compressor station in Richmond, through communities including Gardiner and Augusta, to Madison. If both pipelines are built, they could be competitors.

Brunswick-based Maine Natural Gas could apply for state and local permits this spring, with hopes of starting construction on the east side this year and being in service in 2012, according to Dan Hucko, director of media relations for Iberdrola USA, a subsidiary of a Spanish energy company.

The company’s longer term plans include a second phase crossing the Kennebec River and extending along Western Avenue and Leighton Road to the north Augusta commercial area, starting in 2013.

Hucko declined to identify what customers the firm has contacted, nor confirm whether the state government, which has a major office complex on Hospital Street, is a potential user.

The line would distribute gas from a Maritimes and Northeast high pressure pipeline coming from Canada.

Maine Natural Gas has built and continues to expand systems in Brunswick, Topsham, Windham, Gorham, Bowdoin, Freeport and Pownal. It has about 2,700 customers.

Company officials today declined to disclose the estimated cost of the project, but said they have the financing to do it and do not plan to ask communities for tax breaks, as Kennebec Valley Gas has done.