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.
This development takes natural gas found in coal seams and ships it 260 miles by pipeline to an island off the northeast city of Gladstone.
From there the gas is liquified by chilling it to -258 Fahrenheit, then loaded onto tankers for export. Natural gas is used by power companies, various other industries and by consumers for heating and cooking.
It's one of six Australian natural gas projects on this list, which speaks to the continent's vast natural resources and its proximity to fast growing Asian markets.
Natural gas' clout in the world's energy mix is growing quickly. Some of the natural gas projects on this list may employ hydraulic fracturing -- or fracking for short -- which some fear may contaminate ground water.