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1.
Current legislation on power production from nuclear energy in Germany defines certain remaining quantities of permitted electricity production for nuclear power plants. These quantities are defined for each nuclear power plant and are measured in TWh. In the discussion about climate protection and market trend of electricity prices, it is regularly stated by policy makers that the nuclear phase-out will result in an increase in electricity prices and CO2 emissions. As a consequence a revision is proposed, especially from the Liberals (FDP) and Conservatives (CDU). The following article discusses this issue analysing the different options investors and operators under different scenarios have. It shows firstly that both emissions and power prices can indeed increase, and secondly that the mere discussion about potentially reversing the phasing-out decision can lead to an increase in electricity prices as investment behaviour may change based on expectations regarding future regulation. I conclude that – ceteris paribus – the nuclear phase-out is likely to result in an increase in CO2 emissions and prices. 相似文献
2.
About ScienceDirect 《Refocus》2001,2(2):54-55
This column discusses developments and policy regarding the supply and use of green energy. It is a co-operation between Refocus and www.greenprices.com. In each issue key information will be presented on green energy in Europe and abroad. In this issue some observations are made on green energy pricing and market developments in Europe up to the first quarter of 2001. 相似文献
3.
《热科学学报(英文版)》2006,(4)
Contents、b】.15,No.1March 2006Eisuke outaPaseale Kulisa,C6drie Dano14Manabu Takao,Toshiaki Setoguchi Kenji Kaneko,Shuiehi NagataMasashi Kashitalli,Yut砍a、ralnaguchiRotating Stall and Stal】一Controlled Peribrmanee of a Single Stage Subsonie Axial ComPre 相似文献
4.
IntroductionTehran, the Capital of I.R. Iran, is a huge city with acurrent population more than 12 millions, and an area ofapproximately 2000 km', including its suburban. Itlocates at latitode 35" 31' north and longitllde sl" 19,east, in the south part of the Alborz Mountains andsurmunded by mountains from north-west, north, to eastand central desert of iran from west and south. Therefore,Tehran has upward slope from south to north and fromwest to east. There are only some hills (with compa… 相似文献
5.
Radosław Tarkowski Grzegorz Czapowski 《International Journal of Hydrogen Energy》2018,43(46):21414-21427
Salt bearing formations have world-wide distribution. The geological structures of Permian salt bearing deposits in Poland are similar to those in the other parts of the Central European salt basin, to which they belong as its SE part. There is a notable trend to use salt domes as sites for underground storage of various gases, fuels and other substances, including hydrogen. Possibilities of using salt domes in Poland for underground hydrogen storage are presented with the focus on the option of using the underground space for energy storage. Usefulness of the 27 hitherto studied salt domes in the Polish Lowlands for underground hydrogen storage in caverns is evaluated using analytical methods of the geology of mineral deposits.Seven not yet developed salt domes are selected as the most promising ones, taking into account geological and reservoir criteria: Rogó?no, Damas?awek, Lubień, ?ani?ta, Goleniów, Izbica Kujawska and D?bina. Initial experience in underground hydrogen storage in salt caverns is presented. Geological conditions favourable for hydrogen storage in underground caverns leached in salt domes are outlined. Their advantage relative to underground storage sites in porous rocks (depleted hydrocarbon deposits and deep aquifers) is discussed. 相似文献
6.
7.
《International Communications in Heat and Mass Transfer》1994,21(2):237-248
We summarize here the results of wavenumber evolution in Rayleigh-Bénard experiments with air in moderate size rectangular containers. The wavenumber reduction selection mechanism originates from growth of skewed varicose instability, and is facilitated by dynamical motions of dislocation defects in the convection roll pattern. The regime of stable, two-dimensional convection roll patterns in moderate size containers is found to exist, however, at much larger buoyant potential than that observed and predicted in wide horizontal layers. We suggest that this aspect of Rayleigh-Bénard convection in gases derives from a stabilization of the pattern as forced by the modulation effects of all vertical boundaries in the container. The wavenumber evolution reported here accounts for new experimental results, which exhibit two alternative branches in the commencement of the secondary bifurcation structure. 相似文献
9.
Gas–liquid two-phase flow in minichannels and microchannels displays a unique flow pattern called ring film, in which stable waves of relatively large amplitudes appear at seemingly regular intervals and propagate in the flow direction. In this paper, the behaviors of ring waves, which correspond to ring films that appeared in ring film flow and disturbed ring film flow regions, have been investigated experimentally in gas–liquid two-phase flows of nitrogen-distilled water and nitrogen/30 wt% ethanol–water solution in a 150-μm-diameter silica tube to elucidate their generation mechanism and propagation behavior. In order to clarify the existence region and characteristics of ring waves, the flow patterns observed in a microchannel were investigated and flow pattern maps were made. Furthermore, the velocity of the ring wave was also investigated and compared with the gas slug velocity. In these velocity measurements, high-speed video images were taken at 6,000 frames per second and the formation of ring films and the relationship between the wave amplitude and velocity were determined. The results indicate an interfacial instability leading to the formation and growth of ring waves with both low and high wave amplitudes. The wave velocity is correlated to the wave amplitude, with the large amplitude waves moving much faster than the low amplitude waves. As a result, coalescence of large and low amplitude waves has been observed. 相似文献
10.
Though the development of renewable energy is rapid, innovation in renewable energy technologies is relatively weak due to the late commencement of renewable energy in China. In addition, renewable energy is mainly introduced into the supply mix of electricity generation, which increases the costs of electricity generation. Higher electricity price will make renewable energy more competitive and call forth renewable energy technological innovation. Based on FMOLS and DOLS models, as well as PMG model, this paper investigates the induced long and short run effects of electricity price, funding support, and economic growth on innovation in renewable energy technologies at the provincial level in China during the period 2006–2016. The Conclusions drawn were: (1) R&D expenditure and economic growth have positive impacts on innovation in renewable energy technologies in the long and short run; (2) Electricity price only has a long run effect on patenting in renewable energy technologies; (3) In the long run, a 1% increase in electricity price can lead to a 0.7825%–1.0952% increase in the patent counts of renewable energy technologies; (4) Electricity pricing system in China does not play any role in driving renewable energy technological innovation in the short run. 相似文献
11.
Tick Hui Oh 《Renewable & Sustainable Energy Reviews》2010,14(9):2697-2709
Secure, reliable and affordable energy supplies are necessary for sustainable economic growth, but increases in associated carbon dioxide (CO2) emissions, and the associated risk of climate change are a cause of major concern. Experts have projected that the CO2 emissions related to the energy sector will increase 130% by 2050 in the absence of new policies or supply constraints as a result of increased fossil fuel usage. To address this issue will require an energy technology revolution involving greater energy efficiency, increased renewable energies and nuclear power, and the near-decarbonisation of fossil fuel-based power generation. Nonetheless, fossil fuel usage is expected to continue to dominate global energy supply. The only technology available to mitigate greenhouse gas (GHG) emissions from large-scale fossil fuel usage is carbon capture and storage (CCS), an essential part of the portfolio of technologies that is needed to achieve deep global emission reductions. However, CCS technology faces numerous issues and challenges before it can be successfully deployed. With Malaysia has recently pledged a 40% carbon reduction by 2020 in the Copenhagen 2009 Climate Summit, CCS technology is seen as a viable option in order to achieve its target. Thus, this paper studies the potential and feasibility of coal-fired power plant with CCS technology in Malaysia which includes the choices of coal plants and types of capture technologies possible for implementation. 相似文献
12.
Dhananjay Kumar Srivastava Martin Weinrotter Kurt Iskra Avinash Kumar Agarwal Ernst Wintner 《International Journal of Hydrogen Energy》2009
Laser-induced spark ignition of lean hydrogen–air mixtures was experimentally investigated using nanosecond pulses generated by Q-switched Nd:YAG laser (wavelength 1064 nm) at initial pressure of 3 MPa and temperature 323 K in a constant volume combustion chamber. Laser ignition has several advantages over conventional ignition systems especially in internal combustion engines, hence it is necessary to characterise the combustion phenomena from start of plasma formation to end of combustion. In the present experimental investigation, the formation of laser plasma by spontaneous emission technique and subsequently developing flame kernel was measured. Initially, the plasma propagates towards the incoming laser. This backward moving plasma (towards the focusing lens) grows much faster than the forward moving plasma (along the direction of laser). A piezoelectric pressure transducer was used to measure the pressure rise in the combustion chamber. Hydrogen–air mixtures were also ignited using a spark plug under identical experimental conditions and results are compared with the laser ignition ones. 相似文献
13.
《International Journal of Hydrogen Energy》2019,44(5):3264-3276
Hydrogen is seen as an important energy carrier for the future which offers carbon free emissions. At present it is mainly used in refueling hydrogen fuel cell cars. However, it can also be used together with natural gas in existing gas fired equipment with the benefit of lower carbon emissions. This can be achieved by introducing hydrogen into existing natural gas pipelines. These pipelines are designed, constructed and operated to safely transport natural gas, which is mostly methane. Because hydrogen has significantly different physical and chemical properties than natural gas, any addition of hydrogen my adversely affect the integrity of the pipeline network, increasing the likelihood and consequences of an accidental leak. Since it increases the likelihood and consequences of an accidental leak, it increases the risk of explosion. In order to address various safety issues related to addition of hydrogen in to a natural gas pipeline a EU project NATURALHY was introduced. A major objective of the NATURALHY project was to identify how much hydrogen could be introduced into the natural gas pipeline network. Such that it does not adversely impact the safety of the pipeline network and significantly increase the risk to the public. This paper reports experimental work conducted to measure the explosion overpressure generated by ignition of hydrogen-methane-air mixture in a highly congested region consisting of interconnected pipes. The composition of the methane/hydrogen mixture used was varied from 0% hydrogen (100% methane) to 100% hydrogen (0% methane) to understand its effect on generated explosion overpressure. It was observed that the maximum overpressures generated by methane-hydrogen mixtures with 25% (by volume) or less hydrogen content are not likely to be significantly greater than those generated by methane alone. Therefore, it can be concluded that the addition of less than 25% by volume of hydrogen into pipeline networks would not significantly increase the risk of explosion. 相似文献
14.
《International Journal of Pressure Vessels and Piping》2001,78(8):553-565
This paper reports the status of ongoing discussions of the United Kingdom Technical Advisory Group on the Structural Integrity of Nuclear Plant (TAGSI) on the probability of ‘large’ defects in thick-section butt welds in nuclear components. Within this context, large defects are defined as having a through-wall extent greater than approximately 15 mm. TAGSI have restricted their discussions to single planar defects that may occur after fabrication and fabrication inspections but before pre-service pressure testing. Consideration has been given to: (i) the defects that may be present after fabrication, and (ii) the detection of such defects where radiography is applied as the fabrication inspection technique.The main issues considered by TAGSI are:
- (a) The validity of the main defect distributions used for Probabilistic Fracture Mechanics (PFM) calculations on United Kingdom nuclear plant when extrapolated to large defect heights. The lack of any physical justification for such extrapolation has been addressed by detailed consideration of the metallurgical and process causes of defects.
- (b) Observations from non-nuclear data and the relevance of these to thick-section butt welds in nuclear components. The relative dearth of data and the limited information on the reported large defects emphasises the need for an understanding of mechanisms for their formation.
- (c) Methods of ‘modelling’ defect distributions by an expert system procedure rather than deriving them by fitting assumed functions to data for mainly ‘small’ defects. It is concluded that there are limitations to current expert systems for the prediction of accurate defect probabilities.
- (d) The Probability of Detection (PoD) of large defects by radiography. It is concluded that developments in radiography simulation will help to establish the limits within which high PoD could be expected and help to measure and improve human performance. In addition, the use of neural networks could be further developed to complement the role of the inspector.
15.
Yuwen Zhang 《热科学学报(英文版)》1994,(3)
AnalysisofSolidiflcationinthePresenceof HighRayleighNumberConvectioninanEnclosureYuwenZhang(SchoolofEnergyandPowerMachineryEn... 相似文献
16.
This paper examines whether the time variation in the level of investor herding in the stock markets of major oil exporting nations relates to speculation and volatility in the global oil market. We find that speculative activities in the oil market, rather than oil price movements, are positively correlated with anti-herding in the stock markets of major exporters. We argue that traders take the speculative signals from the oil market as a sign of positive expectations and try to generate superior profits by going against the crowd in their local market. While this pattern largely holds during calm (low volatility) market periods, we also find that significant herd behavior takes place during high volatility (or crisis) periods. The findings suggest that policy makers who are concerned about stability in their stock markets should monitor measures of speculative activities in the energy market in order to model and monitor volatility and/or risk transmissions into their markets. 相似文献
17.
IntroductionThe s up ersonic- combus t ion ram j et (s cramj et ) engine is one of the most prollilsing air breathing prOPulsion systems for hypersonic transports. It is essentialto the design of scramjet engines that the fueLair miX-ture remains supersonic throughout the combustor.The subsonic combustion is better than the supersonic combustion from a standpoint of efficiency, bescause total pressure losses in heated supersonic flowsare higher than those in heated subsonic flows withsame st… 相似文献
18.
《International Journal of Hydrogen Energy》2003,28(8):873-879
The optimal angles of inclination for maximum recovery, maximum production rate and minimum column length in a continuous-type flat-plate thermal diffusion column inclined for the improvement in recovery of deuterium (D) from water–isotopes mixture (H2O–HDO–D2O), have been determined. The recovery of deuterium was estimated from the degrees of separation of HDO and D2O. Considerable improvement in performance is obtainable if the column is tilted at the optimal angle of inclination, instead of being placed vertically, so that the convection strength can be properly reduced and controlled, resulting in suppressing the undesirable remixing effect while still preserving the desirable cascading effect. 相似文献
19.
Jun Li 《Renewable & Sustainable Energy Reviews》2010,14(4):1154-1171
This paper examines the current situation of wind industry development, evaluates the potentials of GHG mitigation and identifies the key determinants of scaling up wind power deployment in China. China has doubled its wind capacity every year for the past 4 years, the total installed capacity reached 12 Gigawatts (GW) and surpassed the 10-GW target 2 years ahead of schedule in the national plan for renewable energy development [38], [71], [87],and would reach 100–120 GW by 2020 according to the government’s new energy plan. It may become the biggest wind power generation and wind turbines manufacturing country of the world in the next years if the abundant wind resources and enormous domestic market can be harnessed with appropriate policies and efficient technology. The recent positive move in vigorous development of wind power in China implies that the total installed capacity will far exceed the targets of the government’s 2007 renewable energy plan. However, the prosperous Chinese wind market has also revealed some worrisome signals and weakness [28], [58], such as low capacity factor and frequent outage of wind farms, inadequate grid infrastructure, long distance transmission, low quality of turbines, adverse price bidding, nepotism in wind farm developer selection process and regulatory uncertainty and policy inconsistency which all conspire to hinder effective power generation in the massively new installed wind capacities. A coherent policy framework is required for creating enabling environment for accelerating wind energy penetration and state-of-art technology deployment in the country. It is argued that institutional, financial and technical capacity will need to be cemented to exploit the huge potentials of wind resources to meet the rapidly growing demand for electricity in China in the coming decades with minimised environmental implications. 相似文献
20.
Rudolf Dvorak 《热科学学报(英文版)》1997,(2)
INTRODUCTIoNfoicalofflowsinturbomachineryelemefits,i.e.inclosedcurvedchannels,cascades,etc.aretheirthree-dimensionalcharacterandvariousvorticalstructures(Fig.1).Theymakethewholefiowstructureverycom-plexandintroduceunknowneffectsonotherphenom-enaofinterest,ase.g.theflowseparation,choking,developmentofshockwavesandtheirinteraction,etc.Inclosedchannelsallthesephenomenainteractwitheachother(thesocalledstronginteraction)inamannernotyetfullyunderstood.Itshouldbestressedatthebegiedngthatvorticalf… 相似文献