The energy required for industrial process heat and process power is a major fraction of the primary energy demand in an industrialized nation. Industrial users in the U.S. comprise the largest single category of consumers; they account for about 40% of the total primary energy consumption. This industrial energy demand is presently supplied by fossil fuel sources, primarily natural gas and petroleum, with about a three-to-one ratio between process heat and process power uses. Natural gas supplies about half of this process heat demand, petroleum a little more than a quarter, and coal a little less than a quarter. The recent rapid escalations in petroleum and natural gas prices have had a major economic impact on industrial users; and there are concerns about adequate long-term supplies of these fuels, foreign or domestic, at any price. The present U.S. primary energy demand cannot be met by the doemestic supply of these fuels. Projections for the future supply and demand situation vary somewhat depending on the scenario of use proposed, but all show increasing demand and a diminishing supply with a growing deficit between them over the next 25 or so years. It is obvious that domestic substitutes for petroleum and natural gas and other alternate primary energy sources must be developed if the national energy and economic future is to be secure.