Petroleum is the king of fossil coal Natural gas is the purest fossil fuel Natural gas contains little amount of sulfur It burns at lower temperature, producing less no The efficiency to generate electricity by using gas turbine can be as high as 47% Natural gas can be methane, which is safer, and propane• Petroleum is the king of fossil coal. • Natural gas is the purest fossil fuel. • Natural gas contains little amount of sulfur. It burns at lower temperature, producing less NO. • The efficiency to generate electricity by using gas turbine can be as high as 47%. • Natural gas can be methane, which is safer, and propane