Our growing thirst for energy means today's projects dwarf most past endeavors. The Hoover Dam cost $49 million in 1936. Adjusted for inflation, that's only $825 million today.
The Australia Pacific project will extract natural gas from coal seams in the northeastern part of the country.
China's Sinopec has agreed to purchase a portion of the gas for 20 years. Japan's Kansai Electric has also agreed to purchase some of the gas.
NEXT: #4 - Bovanenkovskoye - $41 billion