HOUSTON, March 1 (Xinhua) -- U.S. Energy Information Administration (EIA) said on Thursday that natural gas is expected to remain the most-consumed fuel in the U.S. industrial sector. EIA quoted the Annual Energy Outlook 2018 (AEO2018) Reference case as saying that the natural gas consumed by the U.S. industrial sector will increase 40 percent, or from 9.8 quadrillion British thermal units (Btu), in 2017 to 13.7 quadrillion Btu in 2050. By 2020, industrial natural gas consumption will surpass the previous record set in the early 1970s. The U.S. industrial sector consumes more natural gas than any other sector, surpassing electric power in 2017 and the combined residential and commercial sectors in 2010. In 2017, about two-thirds of total industrial natural gas consumption was consumed for heat or power applications -- either for industrial processes, such as in furnaces, or for onsite electricity generation. Several industries including bulk chemicals, food, glass, and metal-based durables used natural gas for 40 percent or more of their heat or power applications in 2017. EIA expected that these industries will continue to use about the same proportion of natural gas for heat or power applications through 2050 because of the cost associated with fuel switching. Industrial fuel switching often involves changing manufacturing processes, which requires substantial capital investment in new equipment.