Efficient Power Generation From Large 750°C Heat Sources: Application to Coal-Fired and Nuclear Power Stations

1980 ◽  
Author(s):  
Z. P. Tilliette ◽  
B. Pierre

Considering the concern about a more efficient, rational use of heat sources, and a greater location flexibility of power plants owing to cooling capability, closed gas cycles can offer new solutions for fossil or nuclear energy. An efficient heat conversion into power is obtained by the combination of a main non-intercooled helium cycle with a flexible, superheated, low-pressure bottoming steam cycle. Emphasis is placed on the matching of the two cycles and, for that, a recuperator bypass arrangement is used. The operation of the main gas turbocompressor does not depend upon the operation of the small steam cycle. Results are presented for a conservative turbine inlet temperature of 750 C. Applications are made for a coal-fired power plant and for a nuclear GT-HTGR. Overall net plant efficiencies of 39 and 46 percent, respectively, are projected.

2016 ◽  
Vol 11 (sp) ◽  
pp. 789-797
Author(s):  
Kami Seo ◽  
◽  
Tadahiro Motoyoshi ◽  
Yasunobu Maeda ◽  
◽  
...  

Quake-induced accident of Fukushima nuclear power plant in 2011 triggered heated argument about the country’s energy policy in Japan. Although many people recognized the risk of nuclear energy use, they did not necessarily support the option of abandoning the technology for the near future. This paper focuses on how people perceive risks associated with and without nuclear power generation and how perceived risks affect their opinion. We conducted questionnaire survey targeting 18–20 year old university students, the stakeholders in the future. The survey was implemented in 2013–2014 when none of Japan’s nuclear power plants was in active use. Three quarters of the respondents answered that a future with nuclear power generation was more realistic than without it. The aspects dividing the two groups, i.e., respondents who expect a future with or without nuclear energy use were their evaluations of three themes: (1) the feasibility of renewable energy sources, (2) the impacts in the safety of developing nations’ nuclear power generation, and (3) the difficulty in gaining the acceptance of residents near the power plants. Meanwhile, both groups above were similarly positive about technological innovation, and were similarly and strongly negative about developing safety management.


2021 ◽  
Vol 73 (07) ◽  
pp. 65-66
Author(s):  
Chris Carpenter

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper IPTC 21348, “The Color of Energy: The Competition To Be the Energy of the Future,” by Hon Chung Lau, National University of Singapore, prepared for the 2021 International Petroleum Technology Conference, held virtually 23 March–1 April. The paper has not been peer reviewed. Copyright 2021 International Petroleum Technology Conference. Reproduced by permission. The author of the complete paper, for the purposes of this study, characterizes energies as brown, blue, or green. Brown energies are carbon dioxide (CO2)-emitting fossil fuels, such as gas, oil, or coal. Blue energies use carbon capture and storage (CCUS) technologies to remove the emitted CO2 from brown energies. Green energies are zero- or low-CO2-emitting renewable energies. By analyzing the CO2 intensity and levelized cost of energy of energy carriers of different colors, the author shows that renewable energies are best used in replacing fossil fuels in the power sector, where they have the greatest effect in reducing CO2 emission. Overview By 2017, only 11% of the world’s final consumption came from renewable energies, 85% came from fossil fuel, and 4% came from nuclear energy. Energy consumption can be divided into three sectors: power, transport, and thermal. At the time of writing, 26.4% of global power (electricity) consumption comes from renewable energies. In this sphere, renewable energies are making the most significant contribution in reducing CO2 emission. Forty-one percent of CO2 emission comes from electricity and heat, 21% from transport, and 21% from industry. Consequently, the key to global decarbonization is to decarbonize these three sectors. Green Energy Is Preferred Green energies consist of six major types: solar photovoltaic, solar thermal, wind, hydroelectricity, geothermal, and biomass. If 1 kWh of electricity generated by renewable energy (with the exception of biomass) is used to replace 1 kWh of electricity generated by fossil fuel, the net CO2 savings will amount to 0.8, 0.6, and 0.4 kg for replacing coal, oil, and natural gas, respectively. However, if 1 kWh of renewable electricity is used to generate green hydrogen (H2), which is then used for heat generation in industry, it will yield roughly 0.8 kWh of thermal energy, which replaces the same amount of thermal energy by natural gas. This amounts to a CO2 savings of only 0.16 kg CO2/kWh. Consequently, renewable power has the highest CO2 savings effect if it is used to replace fossil fuel for power generation rather than to replace fossil fuel for heat generation. Decarbonizing the Power Sector The power sector is easiest to decarbonize. The three methods foreseen to decarbonize the power sector are nuclear power, blue electricity generated by fossil-fuel power plants equipped with CCUS, and green electricity produced by renewables. The use of nuclear power plants is a country-specific issue. The dual challenge of nuclear plant safety and nuclear waste storage is a key sustainability issue. Recently, interest has been renewed in the idea of increasing investment in nuclear energy for decarbonizing the power sector. It is noteworthy that the countries for whom more than a quarter of their power generation is provided by nuclear energy are all in Europe.


1980 ◽  
Author(s):  
Z. P. Tilliette ◽  
B. Pierre

A now unavoidable concern is the best possible use of a given energy source in order to meet the demand of power and heat. The most efficient, rational, thermodynamically satisfactory way of producing heat is to cogenerate it with power and to handle it as a by-product. Another basic condition is to supply heat without disturbing the operation of main turbogenerators. Closed helium cycle, non-intercooled, gas turbine coal-fired and nuclear power plants which meet these requirements are presented in this paper. Low-pressure steam and hot water are recovered from the precooler; medium, high pressure steam and steam superheating are generated by means of a bypass arrangement of the recuperator. The concept offers attractive overall energy conversion coefficients, very flexible heat production conditions and significant potentialities of reducing oil consumption. Results are given for the conservative 750 C gas turbine inlet temperature.


Author(s):  
Volodymyr Boiko ◽  
Iryna Miskevych

This article examines the current prospects for developing nuclear energy in Ukraine in terms of sustainable development. The strategic importance of nuclear energy for Ukraine is indicated. The advantages of nuclear energy in the context of electricity production's external costs over other energy generation technologies are noted. Today, nuclear energy is considered the most cost-effective low-carbon energy source. An analysis of reports from the Atomic Energy Agency and the US Department of Energy shows that nuclear power generation is a leader in many countries' energy sector, producing cheaper electricity than traditional TPPs. The main challenges for the energy system of Ukraine are highlighted. Among them are: wear and tear and impact on the environment of thermal generation (equipment at thermal power plants is worn out by 70–90 %); the unsatisfactory pace of modernization of the main generating capacities, mainly TPPs; the inconsistency of the flexibility of the United Energy System (UES) of Ukraine with the development of "green" energy (increasing the share of "green" energy increases the risks of UES sustainability) and the corresponding ill-consideredness in the pace and scale of renewable energy implementation. Lack of shunting power; the need to duplicate the capacity of renewable energy due to the low installed capacity factor (ICUF) and significant dependence on natural and climatic conditions; the need to replace existing nuclear power units, which end their extended service life with new, more modern ones that will meet the latest safety and economy standards; the imperfection of the electricity market, primarily in the context of its sale by nuclear generation producers under bilateral agreements; deficit of investments in the whole fuel and energy complex. The main prospects for the development of nuclear energy in Ukraine are identified. Completion of Units 3 and 4 of Khmelnytskyi NPP (KhNPP) remains a critical prospect. An obstacle to this for Ukraine is the lack of appropriate technologies on the Ukrainian side and the curtailment of cooperation with Russia and companies belonging to this state. Another obstacle is that the promising power units of KhNPP based on WWER-1000 belong to the second generation, which today do not morally meet the latest trends and requirements in efficiency and safety standards. Theoretically, Western leaders in the nuclear industry, Orano and Westinghouse, could develop nuclear power plants based on their next-generation "3" and "3+" reactors, where the essential safety requirements are already embedded in the original design of the unit. Another option would be to implement a small modular reactor technology project in Ukraine. Technologically, this will quickly resolve the issue of load management, which arose due to the rapid increase in the share of renewable energy generation in our country. This type of reactor has a significant advantage, which in addition to the minimum load on the environment is: the possibility of placement in areas where additional services are needed in the energy market; low construction costs; frequency of service and operating time; the full cycle of work with fuel. In general, low-power reactors can be used to implement the strategy of hybrid power generation (renewable + nuclear energy).


Author(s):  
F. C. Mcginty

The expanding use of nuclear energy in the power generation field is such that the maintainability aspects of design and maintenance concepts will soon be of interest to an increasingly larger number of designers, logisticians and human factors engineers. This article presents a broad-brush treatment of the effect that radiations have on maintenance of nuclear power plants. It provides examples of how an acceptable degree of maintainability is achieved on a specific military nuclear power plant despite these deadly radiations. A brief glimpse at present developmental programs that will significantly improve the maintainability of nuclear power plants is presented.


2020 ◽  
Vol 2 (3) ◽  
pp. 153-158
Author(s):  
E. V. YANUSIK ◽  

The article discusses the main prerequisites for the development of nuclear energy in the global econo-my, also defines nuclear energy and discusses the structure of global energy consumption. The article proves that the crucial prerequisite for the development of nuclear energy in the world market is the economic efficiency of nuclear power plants.


2021 ◽  
Vol 11 (2) ◽  
pp. 727 ◽  
Author(s):  
Myeong-Hwan Hwang ◽  
Young-Gon Kim ◽  
Hae-Sol Lee ◽  
Young-Dae Kim ◽  
Hyun-Rok Cha

In recent years, photovoltaic (PV) power generation has attracted considerable attention as a new eco-friendly and renewable energy generation technology. With the recent development of semiconductor manufacturing technologies, PV power generation is gradually increasing. In this paper, we analyze the types of defects that form in PV power generation panels and propose a method for enhancing the productivity and efficiency of PV power stations by determining the defects of aging PV modules based on their temperature, power output, and panel images. The method proposed in the paper allows the replacement of individual panels that are experiencing a malfunction, thereby reducing the output loss of solar power generation plants. The aim is to develop a method that enables users to immediately check the type of failures among the six failure types that frequently occur in aging PV panels—namely, hotspot, panel breakage, connector breakage, busbar breakage, panel cell overheating, and diode failure—based on thermal images by using the failure detection system. By comparing the data acquired in the study with the thermal images of a PV power station, efficiency is increased by detecting solar module faults in deteriorated photovoltaic power plants.


2021 ◽  
pp. 389-411
Author(s):  
Tomasz R. Nowacki

This article discusses one of the solutions adopted in the nuclear energy law, which contributes to the reduction of the investment risk. It is the so-called pre-licensing which involves the assessment of key site or technical factors at the pre-investment stage in order to avoid possible problems at the stage of investment implementation. The author analyses the Polish solutions in the context of the general concept of pre-licensing, with particular respect to: the nature of pre-licensing legal instruments (opinions), the scope and requirements of the application for an opinion, and the binding force of pre-licensing acts. The practical significance of this issue is all the greater considering governmental plans to implement nuclear power in Poland and in the light of recent activities of private entities as to the construction of smaller nuclear power plants. In the latter case, prelicensing instruments are already being exercised in practice.


Author(s):  
C. Caputo ◽  
M. Gambini ◽  
G. L. Guizzi

In this paper a new kind of steam cycle provided with internal combustion is proposed. The internal combustion of natural gas and compressed air inside the steam flow has been conceived to carry out a steam heating (SH a/o RH) until TIT (Turbine Inlet Temperature) much higher than those of the conventional steam power plants. By this internal combustion it seems possible to overcome the present limits to TIT in steam plants which are, as known, especially related to the technological problems of the superheater tube materials in the conventional external combustion steam boilers. The proposed cycle has been named with the acronym GIST (Gas Injection STeam) since the hot gases resulting from a combustion close to stechiometric conditions are injected inside the steam flow. This paper provides a first critical approach to these new kinds of thermodynamical cycles. At the first the thermodynamical and technological problems related to the combustion inside steam are explained and discussed. Then, different plant lay-out solutions are proposed with a critical discussion on their overall performance. At the last two GIST solution have been defined that seem very interesting: the first is an hybrid plant scheme (i.e. provided with multi-fuel supply) which involves performances higher than conventional steam power plants (net electric efficiency of about 47%); the second is a plant scheme with full natural gas supply (i.e. without multi-fuel steam boiler) wich involves very relevant performances (net electric efficiency of about 57%).


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