Alice Springs will today become the fifth official Australian Solar City.

General manager of the Solar Cities initiative Brian Elmer says although energy-saving measures are not compulsory, the project is about finding ways in which residents can voluntarily reduce greenhouse gas emissions.

He says the city will become a test piece for nationally reducing greenhouse gas emissions.

"The idea of a solar city project across Australia is to test how energy efficiency measures - solar energy. smart metering and changed energy payouts - can impact on greenhouse gas emission reduction," he said.