Hybrid and integrated nuclear power, compressed Air energy storage, and thermal energy storage system

While Gen-IV nuclear reactors-with their higher exit temperatures and thus higher quality of energy-are expected to convert a higher fraction of the fission (thermal) energy to electricity, both Gen-II and Gen-III reactors are largely restricted to exit temperatures that range between 290°C and 340°C. This restricts their conversion efficiencies to below 35%, and thus, a very large fraction (~. 65%) of the thermal energy produced in these plants is "wasted." Gen-II (and to a large extent, Gen-III) reactors were designed under economic conditions in which electricity was expensive, and thus, the sale (in the form of electricity) of just one-third of the energy produced in fission was sufficient to break even. However, recent growth of shale gas, growth of (and subsidies for) solar and wind power, increase in operation and maintenance (O&M) cost of nuclear power, and constantly improving device efficiencies (that lead to slower increase in power demand) are making it necessary that for nuclear power plants (NPPs) to compete in the deregulated market place, they must be operated more efficiently. While efforts are underway on all fronts to make nuclear power more competitive, for example, by reducing the O&M cost, major advances can be made by making better use of the energy from NPPs that is currently being released into the environment. An example of such an effort is the recent study to cogenerate electricity and liquid fuels, albeit using high-temperature gas reactors.