Global Energy Model Research Articles

Nuclear power in the global energy-environmental system

Reducing the CO2 emission to cope with the global warming is one of the most challenging issues for the global energy system. Among various technological options for reducing the CO2 emissions from energy production, nuclear power is expected to play a key role if accepted by the society. However, there have been fewer model analyses reported recently on the role of nuclear power in the global energy system when compared with the analyses of the other options such as energy efficiency improvements, renewable energies, and CO2 recovery and disposal. This paper presents, with a newly developed global energy model, a numerical analysis on the value of nuclear option in the global energy system, particularly in terms of CO2 mitigation. With the global energy model, which finds the cost minimum energy system over the time range of 1995–2055, the value of nuclear power is analyzed. The model incorporates detailed descriptions of energy conversion technologies which include, besides electricity generation, various liquefaction and gasification processes of hydrocarbon fuels with the options of CO2 recovery and disposal. For nuclear technologies, LWRs (light water reactors) and FBRs (fast breeder reactors) are taken into account with fuel cycle options. Major findings are: 1) LWRs would be introduced at the maximum level into the cost minimum energy system if their economics is slightly improved from the standard assumption; however, 2) the maximum introduction of LWRs would make only a small effect in reducing the global CO2 emissions; 3) FBRs would be introduced at an almost maximum scale when the stabilization of global CO2 emission is required; 4) the role of FBRs in reducing the global CO2 emission is very robust against the deterioration of their economics; and 5) IGCC (integrated coal gasification combined cycle power generation) with CO2 recovery would replace the role when FBRs are not introduced.

Decision analysis under uncertain CO<SUB align=right>2 regulation policies with a global energy model and its implication for power system planning

Global warming caused by the increase of atmospheric CO2 concentration is regarded as a serious environmental issue. Due to uncertainty relating to the mechanisms of the terrestrial carbon cycle and climate system, solution of the problem is considered to be extremely complicated. In such a context, to conduct a decision analysis under uncertain CO2 concentration control policies, we have developed a global energy model which minimises the expected value of discounted total energy system costs up to the year 2055. In this work, we analyse an optimal future global energy system, particularly focusing on the Japanese electric power sector and present insight into an optimal strategy for energy system development under uncertain CO2 regulation policies.

最適化型世界エネルギーモデルに基づく多地域間CO<sub>2</sub>排出許可証取引のゲーム論的分析

Carbon emissions which would cause global warming were agreed to be constrained at COP3 in Kyoto. In addition, carbon emission permits trading was also approved to be introduced. The emission permits trading is expected to achieve efficient carbon emission reduction, equalizing the marginal costs of the emission reduction for the participating countries. In other words, the permits trading allows participants to reduce emissions where it is least expensive to do so. However, the inadequate introduction of the trading systems may impose an unfairly greater burden on some countries, and therefore careful evaluation of the system would be indispensable for its implementation. In this paper, we attempt to analyze emission permits trading, using the theory of cooperative games with a global energy model of optimization type. We assume that seven world regions as players participate in the permits trading system under the condition of the emission reduction target presented at COP3 and so on, and show the nucleolus of the grand coalition games, and the computational results of primary energy supplies and CO2 shadow prices. The insights of this research indicate that in order to stabilize the grand coalition, a noticeable amount of additional transfer of money would be needed besides the payments associated with the emission permits transactions. © 2000 Scripta Technica, Electr Eng Jpn, 131(2): 40–50, 2000

Modeling a Stratocumulus-Topped PBL: Intercomparison among Different One-Dimensional Codes and with Large Eddy Simulation

Several one-dimensional (ID) cloud/turbulence ensemble modeling results of an idealized nighttime marine stratocumulus case are compared to large eddy simulation (LES). This type of model intercomparison was one of the objects of the first Global Energy and Water Cycle Experiment Cloud System Study boundary layer modeling workshop held at the National Center for Atmospheric Research on 16–18 August 1994. Presented are results obtained with different 1D models, ranging from bulk models (including only one or two vertical layers) to various types (first order to third order) of multilayer turbulence closure models. The ID results fall within the scatter of the LES results. It is shown that ID models can reasonably represent the main features (cloud water content, cloud fraction, and some turbulence statistics) of a well-mixed stratocumulus-topped boundary layer. Also addressed is the question of what model complexity is necessary and can be afforded for a reasonable representation of stratocumulus clouds in mesoscale or global-scale operational models. Bulk models seem to be more appropriate for climate studies, whereas a multilayer turbulence scheme is best suited in mesoscale models having at least 100- to 200-m vertical resolution inside the boundary layer.

世界エネルギーモデルによる不確定なCO2濃度規制下での意思決定分析とその発電部門との関連

世界エネルギーモデルによる不確定なCO₂濃度規制下での意思決定分析とその発電部門との関連

A Bayesian technique for refining the uncertainty in global energy model forecasts

Global energy models have a large degree of uncertainty associated with them. This consists of uncertainty in the model structure as well as uncertainty in the exogenous input parameters. This paper combines Monte Carlo methods with Bayesian updating techniques to provide a method for refining the uncertainty in the Edmonds-Reilly global energy model. The Bayesian updating technique uses likelihood-based windows constructed from actual observations of the output variables to filter out the model simulations that do not conform with the observed output. The windows are based on outputs of energy consumption and carbon emissions. Two alternative model structures are examined: one with uncorrelated input parameters and the other with correlated input parameters. Statistical properties are calculated to measure the effects of windowing on the output distributions. The partial rank correlations between the inputs and outputs and between the inputs are also determined. The prior distributions and correlation structure of the inputs are then revised through the updating process. An application of the windowing process illustrates the effects of capping carbon emissions on the input structure.

1.5. Rational approaches to identifying policy objectives

This paper focuses on the broad problem of specifying objectives or utility functions when making decisions about energy or related fields. Decisions of all sorts from the design of analysis through to global policymaking all depend on objectives, implicitly or explicitly. This paper begins by describing how objectives are commonly specified in bureaucracies, and how this affects decisions in practice. It evaluates these conflicting approaches, and suggests a way of trying to bring them more into harmony. It then applies this approach by developing substantive priorities which I would propose as a first cut for rational decision-making related to energy. The substantive analysis begins by revisiting the issue of discount rates, and suggesting that lower rates should be used than are commonly used today. It then discusses what we can learn from global energy models regarding the possibility of (and prerequisites to) long-term economic growth; it begins with a brief summary of the substantive lessons to be learned, and procedes to a discussion of how these models could be used to help establish priorities in more detail.

Global Energy -- Assessing the Future

The energy problem is one of cost; i.e., the financial costs of developing resources and the real costs of maintaining an acceptable environmental quality. In forecasting the future of global energy production and use, the authors examine alternative means of producing and transforming energy (including nuclear and solar power, shale oil, biomass, coal, and synthetic fuels), and the key factors influencing energy consumption, such as population and gross national product. Using the IEA/ORAU Long-Term Global Energy Model, they develop a baseline forecast of global energy production and use, but explore alternate futures. They conclude that the long-term global energy system will slowly evolve into a diversity of options that will grow rather than shrink. They also conclude that we must learn to live and plan with uncertainty about the details of the future. 60 figures, 120 tables.

The impact of electric heating on the balance of payments

We consider the effects of penetration of heat storage for space heating on the balance of payments. Although electric heating has low thermodynamic efficiency, it may be economically attractive because of the use of cheap fuels. Two operating modes are considered for controlling the heat storage loads and their effects on the load curve. A global energy model is used to determine the evolution of the power-generation and oil-refining sectors. Information derived from this model is used to measure effects on the balance of payments.

The institutional context of science, models, and policy: The IIASA energy study

This article is a complement to Keepin's technical analysis of the energy models and scenarios in the IIASA global energy study, Energy in a Finite World. It analyses the role of formal global energy models in the scenarios and policy conclusions as described in the IIASA Energy System Program's (ESP) own statements. It finds inconsistencies which have confused external audiences, including modelers, as to the importance of properties of formal models in generating authority for policy conclusions. The analysis finds two contradictory images of scientific authority pervading the ESP's published accounts. This article argues that models are more symbolic vehicles for gaining authority than objective technical frameworks. Whilst this is in principle legitimate, it means that the internal processes (and not just the products) of modeling projects are a legitimate subject of public evaluation. Due attention must therefore be paid to the quality and disclosure of such processes. The institutional process of analysis reflects a particular policy style itself and constrains what policies are even conceivable. Claims to scientific analysis and definition of policy problems are themselves symptomatic of a policy framework which is biased at a deeper level than that of specific prescriptions.

A comparative analysis of global energy models

A comparative analysis is presented of seven leading models concerned with forecasts of worldwide energy demand to 1985. There are wide variations in the models' projections of non-communist world demands for OPEC petroleum in 1985. This variation is attributed to differences in assumptions about economic growth and about energy utilization rates. It is concluded that differences in assumptions about economic growth were less important than those about energy utilization rates. Petroleum demand projections were also analysed. Variations in these projections were attributed to different assumptions about economic growth, energy utilization and interfuel substitution possibilities. Variations in assumptions about the latter prove to be the largest single source of differences. Supply assumptions accounted for almost none of the differences between projections.

Global and International Energy Models: A Survey

This paper surveys the important global and international energy models and provides summary information on the major research groups and organizations presently involved in energy modeling. In the first section an introduction is provided to the art and science of modeling and to the important concepts and methodologies used in formulating and implementing models. The second section surveys global models that include an explicit treatment of energy, and the next surveys international energy models. The fourth section summarizes the important research groups and organizations presently involved in the development and application of energy models, and the last section presents a survey and concluding remarks. The authors hope that this survey will facilitate communication between model developers and users, and will be useful both in stimulating research to improve models, and in stimulating the use of models for systematic analysis of the important energy issues facing the world. 36 references.