ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Nov 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
December 2025
Nuclear Technology
Fusion Science and Technology
November 2025
Latest News
X-energy raises $700M in latest funding round
Advanced reactor developer X-energy has announced that it has closed an oversubscribed Series D financing round of approximately $700 million. The funding proceeds are expected to be used to help continue the expansion of its supply chain and the commercial pipeline for its Xe-100 advanced small modular reactor and TRISO-X fuel, according the company.
Peter Burgsmüller, Andreas Jacobi, Jr., Jean-François Jaeger, Max J. Kläntschi, Walter Seifritz, François Vuilleumier, Ferdinand Wegmann
Nuclear Technology | Volume 79 | Number 2 | November 1987 | Pages 167-174
Technical Paper | Nuclear Power Plants for Generation of Heat / Fission Reactor | doi.org/10.13182/NT87-A34034
Articles are hosted by Taylor and Francis Online.
With fossil fuel running out in the foreseeable future, it is essential to develop substitution strategies. The heat market in industrial countries in the Northern Hemisphere has two peaks. The dominant one occurs at ∼90° C and is due to the energy demand for space heating and warm water production. A smaller peak, mainly for metallurgical processes, occurs at ∼1300°C. From thermodynamics considerations, using the high flame temperature of fossil fuels—or electricity—to supply the lower temperature range is obviously wasteful. On the other hand, contemporary light water reactor (LWR) technology makes it feasible to provide the space heating sector with hot water in a district heating network. Basically, existing reactor systems are adequate for this. Some 40 to 50% of the heat demand arises in the range below 120°C, causing a corresponding fraction of air pollution by SO2 and to a lesser extent NOx, if fossil fuels are used. When analyzing an adequate district heating system, units in the 10- to 50-MW power range are found to be most suitable for Switzerland, both with respect to network size and the democratic decision-making structure. They would have the best chance of penetrating and covering the heat market. In a cooperative effort among some members of Swiss industry and the Swiss Federal Institute for Reactor Research, a small LWR for heating purposes only is being developed. The Swiss Heating Reactor (SHR) is a small, 15-bar boiling water reactor. Its core, together with its primary heat exchanger, is located in a reactor pressure vessel and a shroud within an underground water pool. This pool acts both as an emergency heat sink and as a biological shield and has a steel-lined concrete containment. The pool is dimensioned to leave the concrete ultimately inactive. The built-in safety and reliability of the SHR are better than for conventional nuclear power reactors, and the admissible risk curve to an individual is set correspondingly low. The economic target of 100 to 120 Swiss franc/MW · h heat for consumers seems achievable.
