each of the technologies under investigation in Vision 21 and to create a strategy for overcoming them (NETL, 2001). Vision 21 envisions the development of technology modules selected and configured to produce the desired power, process heat, or fuel and chemical products from the feedstocks, which would include fossil fuels and, when appropriate, opportunity feedstocks (e.g., biomass, municipal waste). These technology modules will be based on the advanced technologies under development in the program, which are identified in the technology roadmap as (1) gasification, (2) gas purification, (3) gas separation, (4) fuel cells, (5) turbines, (6) environmental control, (7) sensors and controls, (8) materials, (9) computational modeling and virtual simulation, (10) systems analysis and systems integration, (11) synthesis gas conversion to fuels and chemicals, and (12) combustion and high-temperature heat exchange.

The Vision 21 Program Plan anticipates a variety of possible energy plant configurations processing a variety of fossil and waste fuels and producing a varied slate of products to meet specific market needs. In most cases, the primary or only product will be electricity, but other products such as transportation fuels, chemicals, synthesis gas (syngas), hydrogen, and steam might also be produced depending on location and market factors. The use of fossil fuels as a possible pathway to producing hydrogen is also in keeping with the growing interest of DOE in supporting the development of technologies for hydrogen production and use. Vision 21 energy plants will have challenging performance targets for efficiency of fuel-to-electricity generation, conversion of feedstocks to fuels, environmental emissions, and cost (see Chapter 1).¹ The targets for emissions include a 40 to 50 percent reduction in CO₂ emissions by efficiency improvement and essentially a 100 percent reduction if the CO₂ is separated and sequestered, preventing its release to the atmosphere.

Vision 21 was originally conceived as, and to a large extent remains, a very broad and inclusive program. It addresses all fossil fuels, as well as opportunity feedstocks, the conversion of these resources into secondary fuels as well as electricity, the use of both steam and gas cycles, a wide range of scales, and plants designed with and without sequestration-ready greenhouse gases. Given the ambitious and challenging goals, targets, and time scales of the Vision 21 Program and the financial resources available, the committee believes the program’s