Faheem Khalid Lodhi, 36, a Pakistan-born architect, was convicted by a New South Wales Supreme Court jury in June on terrorist charges of trying to buy chemicals that could be used to make explosives and obtaining maps of the national power grid.

Lodhi's case was one of the first launched under tough and controversial anti-terror laws passed in Australia in response to the September 11, 2001, terrorist attacks in the United States.

Justice Anthony Whealy on Wednesday sentenced Lodhi to 20 years in prison on the charge of making inquiries about buying chemicals that could be used to make explosives. He was also sentenced to 10 years each on charges of buying the maps and having an Urdu-language manual outlining terrorist techniques.

Lodhi's sentences were to be served concurrently, and were backdated to the time of his arrest in 2004. He will be eligible for parole in 2019.

Whealy said the plot appeared to be in "very preliminary" stages but that tough punishment was needed anyway because Lodhi's actions "displayed an intention on his part that a violent terrorist act or acts would be carried out in Australia."

"It carried the obvious consequence that, if carried out, it would instill terror into members of the public so that they could never again feel free from the threat of bombing attacks within Australia," Whealy said.