The pressure cooker is the most effective method.

CNN: SHARE THIS

It extracts oil from the ground using a method called fracking - pumping down a mixture of sand, water and chemicals at high pressure.

BBC: US to become 'world's biggest oil producer'

Dale is developing a method to break these bonds by treating plant matter with ammonia at 200 degrees Fahrenheit under 250 pounds of pressure for five minutes.

FORBES: Magazine Article