Nuclear Energy and Process Heating

Abstract

Nuclear energy generated in fission reactors is a versatile commodity that can, in principle, satisfy any and all of manlund's energy needs through direct or indirect means. In addition to its dominant current use for electricity generation and, to a lesser degree, marine propulsion. nuclear energy can and has been used for process heat applications, such as space heating industrial process heating and seawater desalination. Moreover, a wide variety of reactor designs has been employed to this end in a range of countries. From this spectrum of experience. two design approaches emerge for nuclear process heating (NPH): extracting a portion of the thermal energy from a nuclear power plant (NPP) (i.e., creating a combined heat and power, or CHP, plant) and transporting it to the user or deploying dedicated nuclear heating plants (NHPs) in generally closer proximity to the thermal load. While the former approach is the basis for much of the current NPH experience. considerable recent interest exists for the latter. typically involving small, innovative reactor plants with enhanced and passive safety features. The high emphasis on inherent nuclear safety characteristics in these reactor designs reflects the need to avoid any requirement for evacuation of the public in the event of an accident, and the desire for sustained operation and investment protection at minimum cost.Since roughly 67% of mankind's primary energy usage is not in the forrn of electricity, a vast potential market for NPH systems exists, particularly at the low-to-moderate end-use temperatures required for residential space heating and several industrial applications. Although only about 0.5% of global nuclear energy production is presently used for NPH applications, an expanded role in the 21'' century seems inevitable, in part, as a measure to reduce greenhouse gas emissions and improve air quality. While the technical aspects of many NPH applications are considered to be well proven, a determined effort would be needed to achieve more significant near-term use. The timing and extent of this implementation will of course depend on the rate of escalation of fossil-fuel prices, the local availability of alternative energy sources, and the general level of public confidence in nuclear technology.This paper reviews the prospects for NPH systems, including the nature of the potential market, some of the promising NHP reactor design options of current interest, and Canadian and global experience.