Geothermal energy

The Earth's heat may be concentrated under particular structural and hydrogeological conditions, when it can represent a valuable alternative source of energy. Thermal groundwater can be used directly for heating, and natural steam reservoirs can be tapped to drive turbines for electricity generation.     

A consistent algorithm for quasigeostrophic energy and energy flux analysis

The energy flux vector is familiar to geophysical fluid dynamics, but only in the abstract. Equations for computing the energy balance and the energy flux vector (S) for a quasigeostrophic numerical ocean model are provided in both analytic and finite difference form. The multilayer model includes wind, lateral and bottom friction, and bathymetry. The finite difference approximation to the analytic energy balance is consistent with the finite difference approximation to the quasigeostrophic potential vorticity equation. An application of the algorithms to a simple steady ocean gyre illustrates their use. This choice of the flux vector (from an infinity of possibilities) has several advantages: it is computationally convenient; it is capable of field measurement; it has nice mathematical properties in the limit of small amplitude motion; and it facilitates intuition about the dynamics.     

Water and energy

The science and engineering required for harnessing the energy from falling water are well established; the basic concepts are understood by the general public, and up to the last decade, there was strong public acceptance in developing water resource projects to provide an economic, reliable, and renewable source of electric power. At this time, however, water development projects are being critically analyzed with regard to overall justification on an economic, environmental and social basis. Further, various alternative power sources are being considered, which are widely variable with regard to economic justification, environmental effects, social and political problems, technology, reliability, and practical utilization.The purpose of this paper is to present a brief, nontechnical review of the principles of hydropower in order to give a non-water specialist an understanding of its overall potential and capabilities as well as problems related to its development. The paper considers the association between water and energy as related to hydropower, but it does not attempt to analyze the use of water in developing other forms of energy from thermal sources. The discussion presents a brief summary of (1) the historical background and physical concepts of hydropower; (2) the elements of hydropower engineering; (3) the overall availability of hydropower on a worldwide basis; (4) the integration of hydropower projects into multipurpose water development programs; (5) the environmental aspects of hydropower development; (6) and a case study of the Columbia River development.     

Managing energy emergencies

In the past few years the United States has experienced several emergencies due to energy shortages, and more loom in the future. This paper presents a model for studying energy emergencies and applies the model in a framework to analyze a natural gas shortage in New England. The framework assesses events initiating emergencies, supply/demand disruptions, social and economic impacts, characteristics of emergencies, and societal responses. In concluding, the paper suggests how we can become better managers of potential energy emergency situations.     

能源转型背景下不可忽视的新能源:天然氢

世界能源结构正面临着从化石能源向非化石能源过渡的第3次转变,氢气作为易燃且燃烧时不产生污染的清洁能源,将在其中起到重要作用.目前,氢的工业生产主要通过煤、天然气等化石燃料以及电解水制取,对天然氢的勘探开发刚刚起步,仅在非洲马里开采出天然氢.但是,天然氢已在世界各地被陆续发现,据相关文献报道:天然氢可能来源于深源、水岩反...     

Petrothermal energy and geophysics

The geological-geophysical, methological, and economic aspects of extraction and utilization of petrothermal resources (“hot dry rock thermal”) for thermal and electric energy production were considered. Heat collectors are hydraulic fracturing zones of natural or artificially made cracks in the crystalline rocks of the basement; these rocks have higher temperature and can be a kind of “thermal cauldron.” Detection of such “collectors” can be carried out by geophysical methods. When pumped out of wells and warmed to 100–300°C, waters function as a heat transfer for thermal energy supply and electric energy generation. If the technical problem of the rapid drilling of 6–10 km wells could be solved, then petrothermal energy will become competitive with the traditional types of energy production and supply.     

Burst energy release index

Conclusions Rockbursts occur under certain combinations of geologic and mining conditions. It is possible to assess burst prone rocks utilizing BERI during the planning, design and operating stages of the mine. The simplicity of the approach may encourage its use as a quantitative predictor in investigations on rockbursts.     

煤岩组合体峰前能量分布公式推导及试验

冲击地压一定是在能量驱使下发生的,为探索引发冲击地压的能量在煤岩系统中的积聚层位,构建了煤岩组合体力学模型,推导了煤岩组合体峰前能量分布公式,对细砂岩−煤（fine sandstone-coal,简称FC）、粗砂岩−煤（gritstone-coal,简称GC）、细砂岩−煤−粗砂岩（fine sandstone-coal-gritstone,简称FCG）3种组合体开展5种加载速率下的能量积聚规律试验,分析了组合体破坏特征、力学特性及能量积聚规律。试验表明：（1）在0.001 mm/s加载速率下,组合体峰前能量主要以原生裂纹的扩展、贯通的形式缓慢耗散,属于塑性完全破坏;在0.1 mm/s加载速率下,组合体峰前能量主要以局部弹射破坏的形式快速释放,属于脆性不完全破坏。（2）组合体的抗压强度、弹性模量、峰前能量、冲击能量指数与加载速率呈对数关系。随着加载速率增大,组合体抗压强度、弹性模量、冲击能量指数增幅逐渐减小,峰前能量增长率呈现低－高－低的趋势。（3）随着加载速率增加,煤组分储能增多,能量占比增大。在0.001～0.010 mm/s加载速率下,煤组分积聚能量增加较快;在0.010～0.100 mm/s加载速率下,煤组分积聚能量增加较慢。（4）相同加载速率下,煤组分能量占比顺序：FC组合体＞FCG组合体＞GC组合体。（5）组合体中煤组分能量占比均大于50%,煤组分是能量积聚的主要载体。相同应力条件下,软弱岩层能量积聚能力强于坚硬岩层,更易积聚能量。研究结果可为确定冲击地压能量积聚层位和释能减冲工作提供参考。     

水体势能的大气复氧法——势能增氧生态床法

天然河流水质受到污染,但水能依然存在且可以利用。研究了利用水体的势能进行大气复氧的方法,并将其引进污水生物处理领域。被污染的河水通过势能增氧生态床法进行原位生态修复后,其水质可达到地表水Ⅲ类标准,而且大大降低了污水处理费用。该研究革除了鼓风曝气进行大气复氧(利用动能),突破了污水生物处理的"障碍",充分发挥利用水体势能进行大气复氧的运行费用低的优点,开辟了水能利用的新领域。     

植被大气间能量储存分项对能量闭合率的影响分析

植被大气间能量储存分项对能量闭合的影响在地表能量平衡研究中有重要意义。以张掖市盈科灌区玉米农田为研究区,在采用TDEC（Thermal Diffusion Equation+Correction）方法修正土壤热通量的基础上,分析了植被大气间能量储存分项对能量闭合率的影响。结果表明：能量储存分项对于能量闭合率具有一定的提升作用,平均提升幅度约为5.18%。能量储存分项对能量闭合率的影响与有效能量（R_n-G）相关。各能量储存分项对能量闭合率的贡献从大到小依次为：光合作用 >植被冠层热储存 >空气热储存 >空气湿度变化≈露水焓变,其中后两项量级极小,可在相关研究中忽略。量级较大的前三项能量分项具有明显的单峰日变化趋势,其中光合作用项相对另两分项在时间上有所滞后。此外,不同天气条件下（如有云和无云）能量储存分项对于能量闭合率的影响不同,有云时其影响相对较大。     

Gibbs energy of aluminous minerals

The discrepancy between the tabulated Gibbs Energies of Formation for Al₂SiO₅ and corundum relative to muscovite and kaolinite is considered to lie principally with the latter two minerals. New values for heat of formation of gibbsite [Gbs] will affect the tabulated H _f ⁰ , G _f(298,1) ⁰ for the other aluminous minerals which are referred to gibbsite as calorimetric aluminum reference. Gibbs Energy Difference Functions, calculated from phase equilibria in the system CaO-Al₂O₃-SiO₂-(H₂O-CO₂), can be used to estimate consistent H _f ⁰ , G _f(298,1) ⁰ values for aluminous minerals. A self consistent data set is presented referred to G _f(298,1) ⁰ [Corundum]=–378.08 kcal mol^–1. Two independent values for G _f(298,1) ⁰ [Anorthite]=–961.52 and –960.29 kcal, from a recalculation of the H _f ⁰ [Anor] based upon the revised H _f(298,1) ⁰ [Gbs]=–309.325 kcal mol^–1 and from measurement of silica activity on the anorthite-saturated part of the CaO-Al₂O₃-SiO₂ liquidus, respectively, are considered to show the magnitude of the discrepancy and are used in the calculations.     

India at crossroads for energy

As one of the fastest growing economies and further larger consumer of energy in the world,there has been a paradigm shift in India's energy demand.Here we evaluate the growth of Indian economy its,diversification of agriculture-based economy to industrial production,service and digital-technology based economy and deepening of income sources,although the dependence on foreign sources for energy demands has not markedly improved.This situation has placed India at the crossroads for energy sufficiency,especially under the highly fluid and changing geopolitical,strategic,environmental and economic scenarios of the World order.We attempt to un-derstand the issue from geological perspective and address some of the impediments.     

Role of nuclear energy,geothermal energy,agriculture, and urbanization in environmental stewardship

The global issue of atmospheric variations and global warming caused by diverse anthropogenic behaviors is a global concern. There is apprehension about preserving an uncontaminated atmosphere and attaining optimal nuclear and geothermal energy utilization with agriculture sector development. In this regard, this paper investigates the influence of nuclear energy, geothermal energy, agriculture development, and urbanization on carbon emissions and ecological footprint from 1990Q1 to 2019Q4 in the case of China. The findings of unit root tests reveal that all variables are stationary at first integration order, and cointegration test findings confirm the presence of long-run relationships among series. The quantile autoregressive distributive lag (QARDL) method findings demonstrate that nuclear energy, geothermal energy, and urbanization statistically correlate with CO2 emissions and ecological footprint across all quantiles, indicating that these determinants have contributed to environmental degradation. Whereas agricultural development has a statistically significant and negative influence on the environment, implying that agriculture has a pollution-mitigation impact. Based on these empirical findings, several policy implications are presented to preserve environmental quality to achieve the 2030 Sustainable Development Goals (SDGs) target.     

Iran’s energy policy: Current dilemmas and perspective for a sustainable energy policy

Iran is facing large challenges in the area of energy policy. In order to illuminate these challenges and the problems and possibilities, which are present, firstly, the current energy consumption patterns have been analyzed in Iran as well as the energy policy of the Iranian government. Based on this analysis, the alternative concepts have been then formulated for Iran’s future energy. The increase in energy usage in Iran is distinctly out of proportion with the development of economic productivity. Negative structural characteristics of this system are: first, an above average energy intensity; second, an increase in energy consumption in the traffic sector; third, a high growth rate in usage of electric energy; and lastly, an above-average amount of stress to the environment. Traditionally, Iran’s energy policy has focused on satisfying the growing demand for energy by oil and, in the last fifteen years, by successively expanding natural gas. However, the further development of the natural gas supply only makes sense within the context of a holistic energy policy, which takes into account the principles of sustainable development. In the short term, such a policy would take advantage of both considerable energy saving techniques, as well as potential renewable energy sources. In the long term, such a policy would strive for the complete transfer to renewable energy sources and technology.