The International Atomic Energy Agency (IAEA) is developing software to perform economic analysis related to hydrogen production. The software is expected to analyse the economics of the four most promising processes for hydrogen production. These processes are: high and low temperature electrolysis, thermochemical processes including the S-I process, conventional electrolysis and steam reforming.

Entergy is the second largest nuclear owner/operator in the United States with five nuclear units in the south operating under a cost of service structure and an additional six units in the Northeast and Midwest operating as merchant generating facilities. As a major nuclear operator in the merchant sector, Entergy wears the risk of nuclear operations – revenues are directly dependent upon operational performance. Our investment in merchant nuclear operations reflects our belief that use of nuclear energy in the competitive merchant environment can be an economically viable business venture.

Both nuclear and solar energy represent significant carbon-free sources, which may contribute robust elements to a cleaner energy economy, to develop domestic energy sources for the purpose of energy security and stability, and to reduce national dependencies on imports of fossil fuels. Hydrogen, on the other hand, represents a fuel which is clean, powerful and an environmentally benign source of energy to the end-user. The current production of hydrogen is mainly based on hydrocarbons as feedstock, e.g. steam reforming of natural gas.

Over the next 40 years, the combustion of fossil fuels for generation of electricity and vehicle transportation will be significantly reduced. In addition to the business-as-usual growth in electric energy demand for the growing world population, new electricity-intensive industries, such as battery electric vehicles and hydrogen fuel-cell vehicles will result in further growth in world consumption of electric energy. Planning for a sustainable supply of electric energy in the diverse economies of the world should be carried out with appropriate technology for selecting the appropriate large-scale energy resources based on their specific energy. Analysis of appropriate technology for the available large-scale energy resources with diminished use of fossil-fuel combustion shows that sustainable electricity supply can be achieved with equal contributions of renewable energy resources for large numbers of small-scale distributed applications and nuclear energy resources for the smaller number of large-scale centralised applications.

The DOE Nuclear Hydrogen Initiative (NHI) is investigating candidate technologies for large scale hydrogen production using high temperature gas-cooled reactors (HTGR) in concert with the Next Generation Nuclear Plant (NGNP) programme. The candidate processes include high temperature thermochemical and high temperature electrolytic processes which are being investigated in a sequence of experimental and analytic studies to establish the most promising and cost effective means of hydrogen production with nuclear energy. Although these advanced processes are in an early development stage, it is important that the projected economic potential of these processes be evaluated to assist in the prioritisation of research activities, and ultimately in the selection of the most promising processes for demonstration and deployment.

We analyse the market viability of four potential nuclear hydrogen technologies. We focus on the value of product flexibility, i.e. the value of the option to switch between hydrogen and electricity production depending on what is more profitable to sell. We find that flexibility in output product is likely to add significant economic value to a nuclear hydrogen plant. Electrochemical technologies lend themselves more easily to flexible production than thermochemical technologies. Potential investors in nuclear hydrogen may therefore see these as more viable in the marketplace.

A new energy transformation system based on carbon recycle use was discussed. A concept of an Active Carbon Neutral Energy System (ACRES) was proposed. Carbon dioxide is regenerated artificially into hydrocarbons by using a heat source with non-carbon dioxide emission, and the regenerated hydrocarbon is re-used cyclically as an energy carrier media in ACRES. Feasibility of ACRES was examined thermodynamically in comparison with hydrogen energy system. Carbon monoxide was the most suitable for a recycle carbon media in ACRES because of relatively high energy density in comparison with hydrogen, and high acceptability to conventional chemical, steel and high-temperature manufacturing industries. A high-temperature gas reactor was a good power source for ACRES. ACRES with carbon monoxide as recycle media was expected to be one of the efficient energy utilisation systems for the reactor.