Assessment of demand for natural gas from the electricity sector in India

Electricity sector is among the key users of natural gas. The sustained electricity deficit and environment policies have added to an already rising demand for gas. This paper tries to understand gas demand in future from electricity sector. This paper models the future demand for gas in India from the electricity sector under alternative scenarios for the period 2005–2025, using bottom-up ANSWER MARKAL model. The scenarios are differentiated by alternate economic growth projections and policies related to coal reforms, infrastructure choices and local environment. The results across scenarios show that gas competes with coal as a base-load option if price difference is below US $ 4 per MBtu. At higher price difference gas penetrates only the peak power market. Gas demand is lower in the high economic growth scenario, since electricity sector is more flexible in substitution of primary energy. Gas demand reduces also in cases when coal supply curve shifts rightwards such as under coal reforms and coal-by-wire scenarios. Local environmental (SO₂ emissions) control promotes end of pipe solutions flue gas de-sulfurisation (FGD) initially, though in the longer term mitigation happens by fuel substitution (coal by gas) and introduction of clean coal technologies integrated gasification combined cycle (IGCC).     

Mechanical experiments and constitutive model of natural gas hydrate reservoirs

Natural gas hydrate is a new type of green energy resources and has great development prospects, and it has attracted worldwide attentions. The exploitation of natural gas hydrate may result in a series of geological disasters. Therefore, the constitutive model of natural gas hydrate bearing sediments needs to be established to reveal deformation laws of the reservoir sediments and accurately evaluate mechanical properties of hydrate reservoirs. This is the basic guarantees for the effective exploitation of natural gas hydrate resources. The triaxial compressive tests were conducted on samples of natural gas hydrate sediment. Furthermore, the Duncan-Chang hyperbolic model was modified by considering the influences of hydrate saturation based on the test results to obtain the constitutive model according with the deformation characteristics of natural gas hydrate reservoirs. The results show that the stress-strain curves of natural gas hydrate reservoirs show unobvious compaction stage and peak strength, short elastic stage, long yield stage, and significant strain hardening characteristics. After applying loads on natural gas hydrate bearing sediments, the internal solid particles were dislocated and slid. When the loads were small, the sediments demonstrated elastic deformation. With the increase of loads, plastic flows appeared in the interior, and the hydrate crystals were re-orientated, thus the sediments showing plastic deformation. Initial tangent elastic modulus increased with the effective confining pressures, which had little correlations with hydrate saturation. Furthermore, the damage ratio increases with the increase of effective confining pressures, while slightly decreases with the increase of natural gas hydrate saturation. The predicted results of stress-strain curves of sediments with different hydrate saturations well coincide with the results of triaxial compressive tests, indicting the feasibility and rationality of this model.     

Israel—New natural gas producer in the Mediterranean

In 2009 and 2010, major offshore natural gas reserves were discovered near the State of Israel. This article examines Israel's newly discovered natural gas reserves and the implications of this discovery for Israel, the Middle East, and the Mediterranean region. The article will discuss Israel's energy security approach; the role of natural gas in Israel's energy consumption patterns; the organization of Israel's natural gas sector; regional political and security implications of the natural gas discoveries; the prospects for export, and the outlook for various natural gas markets. These new discoveries significantly improve Israel's energy security. They may also spur Israel to develop technologies related to utilization of natural gas in a variety of sectors, such as transportation. The discoveries may contribute to the emergence of a number of maritime border delimitation conflicts in the Eastern Mediterranean. At current volumes, the Israeli discoveries will not be a game-changer for gas markets in southern Europe or liquefied natural gas (LNG) markets. However, they will lead to expanded natural gas consumption in the region. In addition, offshore exploration efforts in Israel and in neighboring countries are intensifying. Additional discoveries may turn the Eastern Mediterranean region into a new source of natural gas and oil.     

Long term forecasting of natural gas production

Natural gas is an important energy source for power generation, a chemical feedstock and residential usage. It is important to analyse the future production of conventional and unconventional natural gas. Analysis of the literature determined conventional URR estimates of 10,700–18,300 EJ, and the unconventional gas URR estimates were determined to be 4250–11,000 EJ. Six scenarios were assumed, with three static where demand and supply do not interact and three dynamic where it does. The projections indicate that world natural gas production will peak between 2025 and 2066 at 140–217 EJ/y (133–206 tcf/y). Natural gas resources are more abundant than some of the literature indicates.     

Indicators of security of natural gas supply in Asia

Natural gas has become an increasingly valuable resource and a global commodity. The demand for it has significantly increased. Japan, Korea and Taiwan heavily rely on liquefied natural gas (LNG) imports for their gas supplies from Malaysia, Brunei, Indonesia, Australia and the Middle East. On the other hand, countries like Thailand and Singapore import gas via trans-border pipelines. Gas supply interruptions, volatile gas prices, transportation and distribution bottlenecks, and a growing reliance on imports over longer distances have renewed interest on gas security in Asia. This paper examines the relative vulnerability to natural gas supply disruptions of seven gas-importing countries in Asia for year 2008. Based on four indicators of security of gas supply, a composite gas supply security index is estimated as an overall indication of gas vulnerability for our sample countries. The results demonstrate that there are differences in the values of the overall indicator of gas vulnerability among countries and the assessment is useful in developing an effective strategy of natural gas supply security in countries in the Asian region.     

冰成天然气水合物机理分析

将冰粉与石英砂均匀混合，在一定条件下形成天然气水合物。实验研究表明冰成天然气水合物没有诱导区，开始就进入水合物的成长区。从气-固反应动力学出发，研究了冰成水合物形成机理：冰成天然气水合物过程是冰晶分子对气体分子的吸附、催化和络合相互作用的过程。     

Is inexpensive natural gas hindering the grid energy storage industry?

Grid energy storage is a maturing technology and forecasts of the industry's growth have been promising. However, recent years have realized little growth in actual deployments of grid-level storage and several high-profile storage companies and projects have failed. We hypothesize that falling natural gas prices have significantly reduced the potential profit from many U.S. energy storage projects since 2009 and quantify that effect. We use engineering–economic models to calculate the monthly revenue to energy storage devices providing frequency regulation and energy arbitrage in several electricity markets and compare that revenue to prevailing natural gas prices. We find that flywheel devices providing frequency regulation were profitable in months when natural gas prices were above $7/mcf, but face difficulties at current prices (around $4/mcf). For energy arbitrage alone, we find that the breakeven capital cost for large-scale storage was around $300/kWh in several key locations in 2004–2008, but is around $100/kWh in the same locations today. Though cost and performance improvements have been continually decreasing the effective cost of energy services from storage, fundamental market signals indicating the need for energy storage are at or near 10-year lows for both energy arbitrage and frequency regulation.     

The estimation of fugitive gas emissions from hydrogen production by natural gas steam reforming

In recent years, a significant amount of interest has been directed towards using hydrogen as an alternative source of energy to fossil fuel. Even though hydrogen is emission free in its end use; the production of hydrogen itself requires energy and may cause process emissions including fugitive emissions from various sources, mainly the piping equipment and fittings. The emissions, even though not as large as stack emissions, they may still pose risks to the environment and health especially to the workers within the plant area. This paper presents the estimation of fugitive emissions from hydrogen production process via natural gas steam reforming. Firstly, the natural gas steam reforming process was simulated before the fugitive emissions of carbon monoxide (CO) and greenhouse gases (GHGs), such as methane (CH₄) and carbon dioxide (CO₂) in the process were estimated. Then, the consequent global warming potential (GWP) and the associated health risks due to the emissions were evaluated. A comparison of the GHG fugitive emissions with other sources of GHG emissions over the hydrogen production life cycle was also performed. Methane (CH₄) recorded the highest rate of fugitive emissions contributing to the greatest GWP. On the other hand, CO₂ represented the total stack emissions contributing to 100% of the total GWP. The concentrations of the gases emitted as fugitive emissions (CH₄, CO₂ and CO) in the process area are below the threshold exposure limit indicating that the plant environment is safe for workers daily exposures to the emitted gases.     

Abundant low-cost natural gas and deep GHG emissions reductions for the United States

This paper analyzes the implications of the natural gas revolution on the US’ ability to achieve deep GHG emissions reductions of 80% below 2005 levels by 2050. It uses a hybrid energy-economy model to test how prevailing low US natural gas prices influence the magnitude of the required carbon price needed to achieve this target. While the paper finds in general that lower gas prices resulting from plentiful gas necessitate a higher carbon price to achieve this target, informing firms and consumers in advance about the magnitude of the future carbon price can lower the necessary level.     

The development of natural gas supply costs to Europe,the United States and Japan in a globalizing gas market—Model-based analysis until 2030

Quickly declining natural gas reserves in some parts of the world, increasing demand in today's major gas consuming regions, the emergence of new demand centres and the globalization of natural gas markets caused by the rising importance of liquefied natural gas (LNG) are changing global gas supply structures and will continue to do so over the next decades. Applying a global gas market model, we produce a forecast for global gas supply to 2030 and determine the supplier-specific long-run average costs of gas supplied to three major consuming regions. Results for the three regions are compared and analysed with a focus on costs, supply diversification and the different roles of LNG. We find that while European and Japanese external gas supply will be less diversified in international comparison, gas can be supplied at relatively low costs due to the regions’ favourable locations in geographic proximity to large gas producers. The US market's supply structure on the other hand will significantly change from its current situation. The growing dependency on LNG imports from around the world will lead to significantly higher supply costs but will also increase diversification as gas will originate from an increasing number of LNG exporting countries.     

The reform in the Turkish natural gas market: A critical evaluation

Turkey is in a strategically advantageous position in terms of its natural gas market. Being in the middle of Europe and energy-rich countries of Central Asia, it can be an energy corridor between these two regions. It can import gas from a number of countries and diversify its sources. This situation may also provide motivation for a competitive gas market. The recent reform in the market, which began in 2001, was an attempt to strengthen the natural gas market to this end. However, the reform has not worked out as expected so far. This article discusses recent restructuring efforts in the Turkish natural gas market. We focus on the legal structure and economic consequences of the legal change within the international economic relations. After presenting a detailed discussion of the legal framework, we draw attention to the problems of the industry and difficulties in the transition to a more competitive market structure. In the end, we touch upon some regulatory issues and potential conflicts.     

Modeling and estimation of the natural gas consumption for residential and commercial sectors in Iran

In this paper, a logistic based approach is used to forecast the natural gas consumption for residential as well as commercial sectors in Iran. This approach is relatively simple compared with other forecasting approaches. To make this approach even simpler, two different methods are proposed to estimate the logistic parameters. The first method is based on the concept of the nonlinear programming (NLP) and the second one is based on genetic algorithm (GA). The forecast implemented in this paper is based on yearly and seasonal consumptions. In some unusual situations, such as abnormal temperature changes, the forecasting error is as high as 8.76%. Although this error might seem high, one does not need to be deeply concerned about the overall results since these unusual situations could be filtered out to yield more reliable predictions. In general, the overall results obtained using NLP and GA approaches are as well as or even in some cases better than the results obtained using some older approaches such as Cavallini’s. These two approaches along with the gas consumption data in Iran for the previous 10 years are used to predict the consumption for the 11th, 12th, and 13th years. It is shown that the logistic approach with the use of NLP and GA yields very promising results.     

Performance evaluation of membrane on catalyst module for hydrogen production from natural gas

We have been developing a hydrogen production module with a Pd-based membrane on catalyst (MOC) from natural gas. The MOC module is expected to be more compact and cheaper than the conventional hydrogen production module. To evaluate the hydrogen production performance of the MOC module and to clear the factor that dominates the effective hydrogen production, we compared the reforming performance of the catalytic support without hydrogen permeable membrane and the MOC module at various reaction conditions. As a result, it was cleared that hydrogen permeation through the membrane improves the methane conversion drastically in the MOC module by comparing with the support only module and changing the experimental conditions.     

Exploring the production of natural gas through the lenses of the ACEGES model

Due to the increasing importance of natural gas for modern economic activity, and gas's non-renewable nature, it is extremely important to try to estimate possible trajectories of future natural gas production while considering uncertainties in resource estimates, demand growth, production growth and other factors that might limit production. In this study, we develop future scenarios for natural gas supply using the ACEGES computational laboratory. Conditionally on the currently estimated ultimate recoverable resources, the ‘Collective View’ and ‘Golden Age’ Scenarios suggest that the supply of natural gas is likely to meet the increasing demand for natural gas until at least 2035. The ‘Golden Age’ Scenario suggests significant ‘jumps’ of natural gas production – important for testing the resilience of long-term strategies.     

Households’ willingness to pay for safeguarding security of natural gas supply in electricity generation

Security of energy supply is a major issue for all EU Member States due to Europe's increasing dependence on imported fossil-fuel sources and the continuous rise in energy demand. The latter is of particular importance in electricity sector given the continuously increasing use of gas for electricity generation. In order to properly tackle with the problem, concerted actions are required by the EU Member States in several levels, i.e. legislative, political, etc. Nevertheless, these actions will come at an additional cost paid by the society either through increased electricity bills or through public financing for energy security investments. Thus, such policies should be justified on the basis of cost-benefit analysis. Towards this direction, it may be necessary to take into account non-market costs and benefits, i.e. the value that consumers place on interruptions avoided. In order to explore households’ perceptions and willingness to pay for securing gas supply for electricity production, an empirical study was conducted by means of the contingent valuation method. The results indicate that consumers are willing to pay a premium on their electricity bills in order to internalize the external costs of electricity production, in terms of energy security, which are caused from imported fuels.     

Characteristics and economics of high-efficiency gas turbine cogeneration systems using low BTU gas

Characteristics of high-efficiency gas turbine cogeneration systems using low Btu gas (LBG) are first analysed. Raising the turbine inlet temperature and incorporating a regenerator are both investigated as methods to improve the efficiency of the cogeneration system (CGS). Taking a gas obtained by pyrolyzing municipal refuse as an example of an LBG, various thermodynamic characteristics of the CGS are analysed using a simulation model developed by the authors. Secondly, authors investigate the economics of a CGS for district heating and cooling using the pyrolysis gas, making use of the estimated characteristics. It is shown that the CGS is estimated to be economically feasible, whereas a CGS using conventional high Btu fuel gas (methane gas) is estimated to be economically infeasible under assumed conditions. The impacts of changes in various parameters which determine the economics of the CGS are also investigated, and it is shown that the economics of the system using refuse-recovered LBG can be expected to be further improved owing to future developments in the technology of generating and refining pyrolysis gas.     

High-efficiency power production from natural gas with carbon capture

A unique electricity generation process uses natural gas and solid oxide fuel cells at high electrical efficiency (74%HHV) and zero atmospheric emissions. The process contains a steam reformer heat-integrated with the fuel cells to provide the heat necessary for reforming. The fuel cells are powered with H₂ and avoid carbon deposition issues. 100% CO₂ capture is achieved downstream of the fuel cells with very little energy penalty using a multi-stage flash cascade process, where high-purity water is produced as a side product. Alternative reforming techniques such as CO₂ reforming, autothermal reforming, and partial oxidation are considered. The capital and energy costs of the proposed process are considered to determine the levelized cost of electricity, which is low when compared to other similar carbon capture-enabled processes.     

Bounding the climate viability of natural gas as a bridge fuel to displace coal

Natural gas has significant potential carbon benefits over coal when used for electricity generation, but these benefits can be offset by emissions of fugitive methane or delays in the adoption of near-zero carbon technologies. We analyze the time-evolution of radiative forcing from both natural gas and coal-based electricity generation by calculating average radiative forcing over an interval of time from greenhouse gas emissions under a range of assumptions for fugitive methane leakage, electricity generation efficiency, and delays in the adoption of near-zero carbon technologies. We find that leakage rates of between 5.2% and 9.9% are required for natural gas to result in greater mean forcing than coal over the next 100 years. We show that natural gas infrastructure with modest leakage could remain in place for 1.5–2.4 times the time interval that coal generation would have persisted prior to replacement with near-zero carbon technologies before the climate benefits of replacing coal with natural gas are negated. Natural gas can serve a viable bridge away from coal-based generation if avoiding longer-term climate impacts is prioritized, fugitive methane emissions are minimized, and the large-scale transition to near-zero carbon alternatives is unlikely to happen in the near-term.     

The production of crude oil and natural gas

This paper is directed at examining the impact of changing prices on the level of production of crude oil and natural gas in the United States. By using a cross-correlation test for unidirectional causality it is clearly demonstrated that, for both crude oil and natural gas, domestic production is affected by changing prices. The implications are clear. The decontrol of the price of crude oil and the deregulation of natural gas prices will lead to additional production in the near term.     

基于AVL-BOOST的天然气发动机性能优化仿真

采用AVL-BOOST软件建立了天然气发动机的数学模型,验证了模型的有效性,通过变参数研究,分析了压缩比、点火提前角对发动机动力性和经济性的影响。研究结果表明,随着压缩比的增大,发动机的有效功率和最高爆发压力均呈上升趋势,压缩比在10～13的范围内,最高压力升高率始终在爆震警戒线以下,在点火提前角为27°～36°CA范围内,发动机的有效功率随着点火提前角的增大而增加,同时发动机的燃油经济性得到改善。