World needs mixture of energy sources, expert says

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.