Norwegian energy company Statoil predicts global energy demand should increase 40 percent by 2040 and demand for fossil fuels should lead the way. \"Demand will increase for all types of energy,\" Statoil chief economist Klaus Mohn said in a statement. \"At the same time, we expect continued progress for energy efficiency, amounting to a 40 percent reduction in energy use per dollar of real gross domestic product.\" Statoil, in its annual energy forecast, said the economy should become more green long term but fossil fuels will still dominate the global energy sector. Fossil fuels by 2040 should account for around 73 percent of the global energy mix, compared with 81 percent for 2010, the company said. Statoil\'s review comes after it was among the biggest winners in an auction for oil and natural gas leases in the U.S. waters of the Gulf of Mexico. The company was the highest bidder on 26 leases, bringing its total in the gulf to more than 350. Statoil submitted the highest single bid at $157 million for one block.