Nuclear-Hydrogen Power

Methods for obtaining hydrogen and using hydrogen in power engineering, transportation, and industry, and methods for handling hydrogen (storage and safety) are examined.The concept of nuclear-hydrogen power – using the energy generated by nuclear reactors to produce hydrogen and using this hydrogen in power engineering and industry – is presented. The development of nuclear-hydrogen power will contribute to global energy security and decrease the demand for fuels which affect climate change on our planet.The technologies needed for nuclear-hydrogen power to become a reality – high-temperature nuclear reactors, apparatus for the efficient production of hydrogen from water, hydrogen fuel cells, chemothermal converters, and hydrogen storage and shipment technology – are analyzed.     

HTR's role in process heat applications

Advanced high-temperature nuclear reactors create a number of new opportunities for nuclear process heat applications. These opportunities are based on the high-temperature heat available, smaller reactor sizes, and enhanced safety features that allow siting close to process plants. Major sources of value include the displacement of premium fuels and the elimination of CO₂ emissions from combustion of conventional fuels and their use to produce hydrogen. High value applications include steam production and cogeneration, steam methane reforming, and water splitting. Market entry by advanced high-temperature reactor technology is challenged by the evolution of nuclear licensing requirements in countries targeted for early applications, by the development of a customer base not familiar with nuclear technology and related issues, by convergence of oil industry and nuclear industry risk management, by development of public and government policy support, by resolution of nuclear waste and proliferation concerns, and by the development of new business entities and business models to support commercialization. New HTR designs may see a larger opportunity in process heat niche applications than in power given competition from larger advanced light water reactors. Technology development is required in many areas to enable these new applications, including the commercialization of new heat exchangers capable of operating at high temperatures and pressures, convective process reactors and suitable catalysts, water splitting system and component designs, and other process-side requirements. Key forces that will shape these markets include future fuel availability and pricing, implementation and monetization of CO₂ emission limits, and the formation of international energy and environmental policy that will support initiatives to provide the nuclear licensing frameworks and risk distribution needed to support private investment. This paper was developed based on a plenary session presentation at HTR-2006 which won Best Paper.     

Nuclear energy for transportation: Paths through electricity, hydrogen and liquid fuels

The transportation sector consumes about a quarter of final energy in Japan and worldwide, and presently most of the energy is supplied by petroleum. For global environment and resources, it is important to seek possibilities of replacing a substantial part of the transportation energy by nuclear energy.

For supplying nuclear energy to the transportation sector, investigated are the paths through such ‘energy carriers’ as electricity, hydrogen and synthetic liquid fuels, to the means of transportation such as automobiles. These energy carriers can be produced from nuclear energy, by itself or synergistically with other primary energies like fossil fuels or biomass.

In this paper, possibilities and impacts of these energy carriers to power transportation means are reviewed, and measures and tasks to supply these energy carriers from nuclear energy are examined.

In converting the primary energies into the energy carriers, the synergistic process may be more advantageous than the individual process. Some of the exploratory processes to produce synthetic liquid fuels from fossil fuels and nuclear energy are presented.     

A Feasibility Study on a Future Zero-Carbon Electricity System Based on 100% Nuclear Power in Japan

The realization of a zero-carbon electricity system is of vital importance to CO₂ reduction in an energy system, and nuclear power is expected to contribute to this much more than the intermittent, complicated, and costly renewable energy in the future in Japan. Therefore, in the present study, a future zero-carbon electricity system based on 100% nuclear power was proposed in Japan. The feasibility of the system was studied in terms of the reliability of fluctuations of both the daily and seasonal electricity demand and supply using an hour-by-hour computer simulation. The simulation provided a detailed system design and real-time operation information for the electricity system based on hourly data series of electrical load, nuclear power output, and electricity storage. The obtained results show that the proposed nuclear-powerbased zero-carbon electricity system is technologically feasible with the help of EV batteries and hydrogen for daily and seasonal electricity storage, respectively, and smart control technologies are necessary to operate the whole system. Finally, key issues relating to the implementation of such a system were discussed to highlight the need for continued research.     

Performance analysis of active carbon recycling energy system

A new energy system, called Active Carbon Recycling Energy System (ACRES), based on nuclear power has been introduced for reduced carbon dioxide emissions and the establishment of carbon supply security. In this study, the feasibility of ACRES were estimated thermodynamically by using the reaction enthalpy balance for select recycling hydrocarbons. Carbon monoxide (CO) and simple carbon are appropriate media for ACRES because of their high energy quality, energy density, and reactivity. A high-temperature gas-reactor (HTGR), the first candidate primary energy source for ACRES, was found to be applicable to high-temperature CO₂ electrolysis for CO production. An iron-making process using ACRES is expected to produce lower CO₂ emissions than hydrogen-based iron-making processes. The applicability of ACRES recycling with CO to iron-making was evaluated by enthalpy analysis. ACRES is expected to be a technological solution for a low-carbon society.     

Nuclear carbonization and gasification of biomass for effective removal of atmospheric CO2

By the process of carbonization of biomass a portion of carbon element in biomass is stabilized as solid carbon, and the remaining portion of carbon, which is the volatile product from carbonization, is converted by the subsequent gasification and conversion process to carbon-neutral synthetic fuels, which can replace the fossil derived fuels currently used.In these processes, nuclear energy can effectively be utilized for supplying energy, thus avoiding the CO₂ emission from any biomass or fossil combustion. By utilizing nuclear energy, most of the carbons in biomass are converted to either stabilized solid carbon or carbon-neutral fuels.Thus, significant amount of CO₂ can efficiently be removed from the atmosphere by processing a part of annual growth of biomass, which leads to the decrease of atmospheric CO₂ concentration.     

Synergistic hydrogen production by nuclear-heated steam reforming of fossil fuels

Processes and technologies to produce hydrogen synergistically by the nuclear-heated steam reforming reaction of fossil fuels are reviewed. Formulas of chemical reactions, required heats for reactions, saving of fuel consumption, reduction of carbon dioxide emission, and possible processes are investigated for such fossil fuels as natural gas, petroleum and coal.

In this investigation, examined are the steam reforming processes using the “membrane reformer” and adopting the recirculation of reaction products in a closed loop configuration. The recirculation-type membrane reformer process is considered to be the most advantageous among various synergistic hydrogen production processes. Typical merits of this process are; nuclear heat supply at medium temperature around 550°C, compact plant size and membrane area for hydrogen production, efficient conversion of a feed fossil fuel, appreciable reduction of carbon dioxide emission, high purity hydrogen without any additional process, and ease of separating carbon dioxide for future sequestration requirements.

The synergistic hydrogen production using fossil fuels and nuclear energy can be an effective solution in this century for the world which has to use fossil fuels to some extent, according to various estimates of global energy supply, while reducing carbon dioxide emission.     

Futures for hydrogen produced using nuclear energy

What is the future of hydrogen (H₂) produced from nuclear energy? Assuming that economically competitive nuclear H₂ can be produced, production of H₂ may become the primary use of nuclear energy and the basis for both a nuclear-H₂ renewable (solar, wind, etc.) energy economy and a nuclear-H₂ transport system. The technical and economic bases for these conclusions are described. In a nuclear-H₂ renewable energy economy, nuclear energy is used to produce H₂ that is stored and becomes the energy-storage component of the electrical generating system. The stored H₂ replaces piles of coal and tanks of liquid fuel. Capital-intensive renewable energy sources and nuclear reactors produce electricity at their full capacity. The stored H₂ is used in fuel cells to produce the highly variable quantities of electricity needed to fill the gap between the electricity demand by the customer and the electricity generated by the rest of the electrical generating system. Hydrogen is also used to produce the liquid or gaseous transport fuels. This energy-system architecture is a consequence of the fundamental differences between the characteristics of electricity (movement of electrons) and those of H₂ (movement of atoms). Electricity can be generated, transformed, and used economically on either a small or a large scale. However, it is difficult to generate, store, and transform H₂ economically on a small scale. This distinction favors the use of large-scale nuclear systems for H₂ production.     

A two-step photon-intermediate technique for the production of electricity, chemicals or lasers in nuclear energy conversion

The authors have developed an energy conversion concept, called Photon-Intermediate Direct Energy Conversion (PIDEC), that makes possible a two-step conversion of high grade nuclear energy (fission or fusion) to electricity or other useful high grade energy forms without intermediate thermalization. In PIDEC the nuclear fuel has a low average density, with local scale lengths significantly shorter than the range of the energetic nuclear reaction products. In the first step of the process, the nuclear energetic reaction product energy is transported to a fluorescer gas which converts it into photons. Then, in the second step of the process, the photons are transported out of the nuclear reactor to a medium which converts the photon energy to the desired product high grade energy form, such as electricity. We calculate that electricity can be produced, non-thermally, with an efficiency of up to 30%. With the addition of intermediate and bottoming thermal cycles, efficiency for electricity production could be as high as 70%, double that of conventional nuclear power plants. In addition to electric power, photolysis makes other product forms possible. These products include useful feedstock, or combustion chemicals, such as hydrogen and carbon monoxide, and excited molecular and atomic states, used for laser amplifiers or oscillators.     

核能制氢技术的发展

氢是清洁能源,有非常好的应用前景.但氢是二次能源,需要利用一次能源来生产.以可持续的方式(原料来源丰富、无温室气体排放)实现氢的大规模生产是实现氢广泛利用的前提.核能是清洁的一次能源,核电已经成为世界电力生产的主要方式之一.正在研发的第四代核能系统除了要使核电生产更经济和更安全之外,还要为实现核能在发电之外的领域的应用...     

Physical characteristics and problems of developing a sodium-cooled fast reactor as a source of high-potential thermal energy for hydrogen production and other high-temperature technologies

Hydrogen as an energy carrier will play a considerable role in the future structure of energy production when nuclear reactors will replace fossil fuels. Investigations performed in recent years have shown that the production of large quantities of energy with high efficiency can be accomplished on the basis of thermochemical cycles using reactors with coolant temperature at the exit from the core of about 900°C. A variant of such a fast reactor with sodium as the coolant is proposed. The main physical characteristics and the main problems which must be solved to build such a reactor are presented. According to its properties, this reactor will meet the modern requirements for nuclear and radiation safety. It can also be used in other promising high-temperature technologies, for example, high-efficiency production of electricity. Deceased. (V. B. Bogush) Translated from Atomnaya énergiya, Vol. 106, No. 3, pp. 129–134, March, 2009.     

Climate change gains more from nuclear substitution than from conservation

We show the massive reduction achievable, in both emissions and climate change impact, from enhanced nuclear energy use on the forecasts of future world energy use and its associated environmental impacts. A range encompassing the major scenarios for the World's energy demand have been analyzed using the latest version of the climate-modeling MAGICC/SCENGEN software (Version 4.1). We have updated and predicted the impacts of 80% substitution with CO₂-free sources (likely predominantly nuclear) for coal-fired electricity (by 2030) and for transportation fuel (by 2040). For transportation, hydrogen produced by CO₂-free sources would replace gasoline and diesel fuels. In this paper, to bracket the range of futures, we simply focus on two scenarios from the Intergovernmental Panel on Climate Change's (IPCC), one (A1FI) that is energy-profligate and one (B2) that is energy-conserving.The results show that, interestingly, projected average global temperatures for all scenarios are fairly similar until about 2035 (a further rise beyond the 1990 average temperature of +0.75 ± 0.1 K) regardless of energy usage and its sources. However, by 2050, the different IPCC scenarios diverge markedly. Understandably, A1FI is projected to have noticeably stronger effects than B2 on average global temperatures (about 0.3 K more in 2050) but the effect is much stronger over land at mid and high latitudes (up to almost 1 K more). What is most striking is that the substitution of CO₂-free sources gives projected average temperature rises in 2050 over key land areas (North America and China) that are very similar for the two energy-use scenarios—typically 1–1.5 K because A1FI's additional energy is predominantly supplied by nuclear. In contrast, projected rises with the unaltered cases are markedly different being about 2.5 K for A1FI and 1.5–2 K for B2. The projected changes in rainfall distribution show similar patterns, especially for the expected increases in higher latitudes.With the assumption of no additional policies for substitution of energy sources beyond 2040, temperature divergence between the two scenarios of relative energy profligacy or conservation grows in the latter half of the 21st century, even with substitution. However, the early substitution of nuclear energy and hydrogen appears to buy time and is not crucially dependent on severe, near-term curtailment of energy use. Near-term curtailment is too difficult to implement at a time of rapid industrialization of major emerging economies. Of course, proportionately larger deployments of CO₂-free energy sources are needed for more energy-intensive scenarios.Nuclear power must dominate as the source of CO₂-free energy since it is proven, dependable, available on a large scale, and economic. Social objections to nuclear energy in some countries and quarters are seen as well-meaning but misguided distractions from solving the energy and environmental crises that are now facing world sustainability. The time for real technical, social and political action is now.     

Nuclear energy option for energy security and sustainable development in India

India is facing great challenges in its economic development due to the impact on climate change. Energy is the important driver of economy. At present Indian energy sector is dominated by fossil fuel. Due to international pressure for green house gas reduction in atmosphere there is a need of clean energy supply for energy security and sustainable development. The nuclear energy is a sustainable solution in this context to overcome the environmental problem due to fossil fuel electricity generation. This paper examines the implications of penetration of nuclear energy in Indian power sector. Four scenarios, including base case scenario, have been developed using MARKAL energy modeling software for Indian power sector. The least-cost solution of energy mix has been measured. The result shows that more than 50% of the electricity market will be captured by nuclear energy in the year 2045. This ambitious goal can be expected to be achieved due to Indo-US nuclear deal. The advanced nuclear energy with conservation potential scenario shows that huge amounts of CO₂ can be reduced in the year 2045 with respect to the business as usual scenario.     

Nuclear Process heat—application to fuels and chemical production

Synthesis gas, a mixture of CO and H₂, produced from coal and a HTR nuclear source can be an economic feedstock for synthetic fuel and chemicals production. Such chemicals as hydrogen, ammonia, methanol, steel, can be readily produced from synthesis gas and other raw feedstocks by standard chemical engineering practice. Direct coal liquefaction is accomplished by adding H₂ to a pressurized coal slurry or solution. The use of the HTR to provide both the synthesis gas (using its high temperature capability) and steam or electricity for chemical process application (using its steam bottoming cycle capability) gives substantial conservation advantages in the use of coal compared to the non-nuclear equivalent processes. The desirability of efficiently using both the high and low temperature sources of the HTR requires a coupling between two or more chemical processes and the HTR (in a ‘Chemplex’) if a match is to be made between the high temperature and steam cycles of the HTR and the needs of the chemical processes.     

Modular High-Temperature Helium-Cooled Nuclear Reactor with Spherical Fuel Elements for Electricity and Hydrogen Production

The results of optimizational neutron-physical and thermohydrulic calculations of the core of a modular high-temperature helium-cooled reactor with mobile spherical fuel elements are presented. A special structural feature of such fuel elements is that they contain fuel microelements with multilayered ceramic coatings capable of confining radioactive fission products at high temperatures with deep burnup of nuclear fuel. The thermal power of the reactor is 850 MW(t) with average power density 30 MW/m³ and helium temperature 1000°C at the core exit. This makes it possible to use such reactors to produce hydrogen by a cost-effective high-temperature process using steam conversion of methane and to generate electricity in a one-loop helium turbosystem with efficiency >45%.     

Sustainability by combining nuclear,fossil, and renewable energy sources

The energy industries face two sustainability challenges: the need to avoid climate change and the need to replace traditional crude oil as the basis of our transport system. Radical changes in our energy system will be required to meet these challenges. These challenges may require tight coupling of different energy sources (nuclear, fossil, and renewable) to produce liquid fuels for transportation, match electricity production to electricity demand, and meet other energy needs. This implies a paradigm shift in which different energy sources are integrated together, rather than being considered separate entities that compete. Several examples of combined-energy systems are described. High-temperature nuclear heat may increase worldwide light crude oil resources by an order of magnitude while reducing greenhouse gas releases from the production of liquid fossil fuels. Nuclear–biomass liquid-fuels production systems could potentially meet world needs for liquid transport fuels. Nuclear–hydrogen peak power systems may enable renewable electricity sources to meet much of the world's electric demand by providing electricity when the wind does not blow and the sun does not shine.     

Global transportation scenarios in the multi-regional EFDA-TIMES energy model

The aim of this study is to assess the potential impact of the transportation sector on the role of fusion power in the energy system of the 21st century. Key indicators in this context are global passenger and freight transportation activities, consumption levels of fuels used for transportation purposes, the electricity generation mix and greenhouse gas emissions. These quantities are calculated by means of the global multi-regional EFDA-TIMES energy system model. For the present study a new transportation module has been linked to the EFDA-TIMES framework in order to arrive at a consistent projection of future transportation demands. Results are discussed implying various global energy scenarios including assumed crossovers of road transportation activities towards hydrogen or electricity infrastructures and atmospheric CO₂ concentration stabilization levels at 550 ppm and 450 ppm. Our results show that the penetration of fusion power plants is only slightly sensitive to transportation fuel choices but depends strongly on assumed climate policies. In the most stringent case considered here the contribution of electricity produced by fusion power plants can become as large as about 50% at the end of the 21st century. This statement, however, is still of preliminary nature as the EFDA-TIMES project has not yet reached a final status.     

Economic Analysis Between Diesel and SOFC Electricity via Fusion-Biomass Hybrid Model

The fusion-biomass hybrid model system, which takes waste biomass from municipal and agricultural areas as well as forests as feedstock, produces either diesel through the Fischer–Tropsch (FT) reaction or electricity by the solid oxide fuel cell (SOFC). This system produces synthesis gas by endothermic pyrolytic gasification using high temperature fusion heat. A temperature of over 700 °C of exterior thermal heat from the fusion reactors with a duel cooled lithium lead blanket and its technical extension bring about biomass gasification to produce maximum amounts of chemical energy and synthetic gas, from feedstock. First, synthetic gas that contains hydrogen (H₂) and carbon monoxide (CO) can be converted into artificial diesel (–CH₂–), which is regarded as “carbon–neutral”. The other is to generate electricity by putting synthetic gas into SOFC at various scales, not only at the plant scale but also at the residential scale. This paper aims to conduct an economic analysis of the fusion-biomass hybrid model by comparing diesel and SOFC electricity under the assumption of the investment of a biomass plant with an FT reaction facility and one with SOFC. A sensitivity analysis is performed applying diesel price, electricity price, SOFC efficiency, diesel subsidy, and fusion heat cost. These results can help in targeting which products are economically justified in the circumstances of variable environmental policies under different policies and economic situations, which would have a significant impact on commercial fusion designing.     

Economic viability of small to medium-sized reactors deployed in future European energy markets

Future plans for energy production in the European Union as well as other locations call for a high penetration of renewable technologies (20% by 2020, and higher after 2020). The remaining energy requirements will be met by fossil fuels and nuclear energy. Smaller, less-capital intensive nuclear reactors are emerging as an alternative to fossil fuel and large nuclear systems. Approximately 50 small (<300 MWe) to medium-sized (<700 MWe) reactors (SMRs) concepts are being pursued for use in electricity and cogeneration (combined heat and power) markets. However, many of the SMRs are at the early design stage and full data needed for economic analysis or market assessment is not yet available. Therefore, the purpose of this study is to develop “target cost” estimates for reactors deployed in a range of competitive market situations (electricity prices ranging from 45-150 €/MWh). Parametric analysis was used to develop a cost breakdown for reactors that can compete against future natural gas and coal (with/without carbon capture) and large nuclear systems. Sensitivity analysis was performed to understand the impacts on competitiveness from key cost variables. This study suggests that SMRs may effectively compete in future electricity markets if their capital costs are controlled, favorable financing is obtained, and reactor capacity factors match those of current light water reactors. This methodology can be extended to cogeneration markets supporting a range of process heat applications.     

Future potential of nuclear heat utilization in energy, economy and environment

In this study quantitative analyses are made to clarify the possible roles of S-HTGRs (Small-sized modular High Temperature Gas-cooled Reactors) in our future energy systems. The results obtained show the good possibility of S-HTGRs to compete economically with L-HTGRs (Large-sized HTGR) taking into account the effects of modularization, learning, mass production, and simplification of safety systems. In the electricity market, S-HTGRs can well compete with coal steam electric power and LWR electric power if they are located close to demand areas. In addition the high temperature nuclear heat from small-sized modular gas-cooled reactors has the potential of contributing to reduce the amount of imported fossil fuels and also SO₂, NO_x, and CO₂ emissions.