Than gasoline or diesel? No, they don't. Wikipedia has a large chart on their article for energy density of various sources. Some things are harder to directly compare with each other, but diesel has 38 MJ/L, with jet fuel/kerosene and gasoline at 36/35. Adding ethanol dilutes the energy output some, while pure ethanol is 24. It's still a potent source (but with its own costs and effects that need to be included in the net equation). Chemically petroleum simply has more bonds to break and get energy from.