Texas' state geologist said trying to pick one fuel source to power the world is a losing proposition.
Geologist Scott Tinker maintains it is going to take a variety of fuels to meet the world's electricity and transportation needs.
Tinker spotlighted the need for energy diversity in “Switch,” a 90-minute documentary filmed over two years with energy experts from 11 countries.
Oklahoma Energy Secretary Mike Ming said the film offers one of the best explanations, showing why just one source is not sufficient to meet the world's energy needs.
Tinker spoke Tuesday at Oklahoma City University about unconventional oil and natural gas reservoirs.
Those resources — unlocked by horizontal drilling and hydraulic fracturing — have spurred a boom in domestic oil and gas production, but not without controversy, he said.
Although there is no evidence hydraulic fracturing has contaminated groundwater, opponents of natural gas exploration continue to criticize the practice that involves injecting thousands of gallons of water and sand deep into the ground.
Tinker, the director of the Bureau of Economic Geology at the University of Texas, said natural gas will be a large part of the world's energy future because it is cleaner than coal or crude oil.
Tinker said he asks people who are opposed to fracturing, or fracking, if they favor nuclear power. The alternative to nuclear is coal, which is cheap and abundant, Tinker said, but burning it releases a lot of harmful emissions.
He said anyone opposed to all three of those options must not like electricity.
“You can't not like everything,” Tinker said, noting renewables like wind or solar do not produce enough power to meet the world's needs.
Tinker said world leaders must have some difficult discussions about how to balance its energy mix, a situation made tougher by the differing resources available around the world.
“I think that's a fascinating global conversation,” he said.
Tinker predicts fossil fuels will provide less of the world's energy by 2080, dropping from 70 percent in 1980 to 60 percent in the future, but consumption will rise because of growing global demand.
He said the U.S. shale boom likely will spread to other parts of the globe, making it even more difficult to replace fossil fuels from the world's energy mix.
He said energy efficiency efforts can ease the transition, making him optimistic the change can be made.
“I think we can do it,” he said.