Prime Minister Julia Gillard has promised standards that would ban the building of new "dirty" power stations - but her policy would not cover up to 12 coal-fired plants already proposed across the country.

Launching the first piece of a revised climate policy, Ms Gillard proposed greenhouse gas emissions standards that would rule out new brown-coal fired stations in Victoria unless they came with "clean coal" technology.

But the standards would not stop the development of new black-coal power plants in NSW, Queensland and Western Australia.

The standard would apply only to new stations that are not yet proposed, and could change after consultation with state governments, the energy industry and environment groups.