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Search Results: 1 - 10 of 5335 matches for " solar wind "
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Efficient Optimization Algorithm for Dwindling Payment and Power Management  [PDF]
P. Sangeetha, S. Suja
Circuits and Systems (CS) , 2016, DOI: 10.4236/cs.2016.79186
Abstract: In this current era, rising demand ultimately leads to the scarcity of source in terms of power. To fulfill this inadequacy and because of the availability and easy conversion of electrical energy, hybrid energy system is the best choice for non renewable energy source replacement, which dominates the demand of reliable power. In this paper, we have proposed and analyzed the optimal capacity of the Photovoltaic and Wind as a hybrid system, standing as a foremost motivating force for the public improvement. To provide uninterrupted supply, storage device is used along with the integrated sources. The key pioneering part of this research paper is the performance of the projected system for cost optimization, which is realized by running the Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) algorithms. The result is the baseline system cost necessary to meet the load requirements. The above stated process is implemented using MATLAB. The motivation of choosing these algorithms is because of swift convergence in real time power management. Performance parameter Total Harmonic Distortion (THD) is also calculated for the proposed system.
Early Solar System Solar Wind Implantation of 7Be into Calcium-Alumimum Rich Inclusions in Primitive Meteortites  [PDF]
Glynn E. Bricker
International Journal of Astronomy and Astrophysics (IJAA) , 2019, DOI: 10.4236/ijaa.2019.91002
Abstract: The one time presence of short-lived radionuclides (SLRs) in Calcium-Aluminum Rich inclusions (CAIs) in primitive meteorites has been detected. The solar wind implantation model (SWIM) is one possible model that attempts to explain the catalogue of SLRs found in primitive meteorites. In the SWIM, solar energetic particle (SEP) nuclear interactions with gas in the proto-solar atmosphere of young stellar objects (YSOs) give rise to daughter nuclei, including SLRs. These daughter nuclei then may become entrained in the solar wind via magnetic field lines. Subsequently, the nuclei, including SLRs, may be implanted into CAI precursors that have fallen from the main accretion flow which had been destined for the proto-star. This mode of implanting SLRs in the solar system is viable, and is exemplified by the impregnation of the lunar surface with solar wind particles, including SLRs. X-ray luminosities have been measured to be 100,000 times more energetic in YSOs, including T-Tauri stars, than present-day solar luminosities. The SWIM scales the production rate of SLRs to nascent SEP activity in T-Tauri stars. Here, we model the implantation of 7Be into CAIs in the SWIM, utilizing the enhanced SEP fluxes and the rate of refractory mass inflowing at the X-region, 0.06 AU from the proto-Sun. Taking into account the radioactive decay of 7Be and spectral flare variations, the 7Be/9Be initial isotopic ratio is found to range from 1 × 105 to 5 × 105.
Solar Activity, Solar Wind and Geomagnetic Signatures  [PDF]
Jean-Louis Zerbo, Frédéric Ouattara, Christine Amory Mazaudier, Jean-Pierre Legrand, John D. Richardson
Atmospheric and Climate Sciences (ACS) , 2013, DOI: 10.4236/acs.2013.34063

The present study investigates solar events through geomagnetic activity and physical processes on the Sun: 1) Quiet activity (QA) related to the slow solar wind, 2) Recurrent activity (RA) related to high and moderate speed solar wind streams from coronal holes, 3) Shock activity (SA) identified by observations of SSCs and 4) Unclear activity (UA) which contains all activity not covered by the first three cases. For recent cycles, we analyze and emphasize some important results: Quiet activity is predominant for cycle 23, comprising 40% of the total activity and over 80% of the activity near solar minimum. Shock and recurrent activity contributions to total geomagnetic activity are largest in cycle 20. The most fluctuating events are observed during cycles 21 and 22. Throughout solar cycle 23, the contribution, from each type of activity, differs from recent solar cycles, with larger percentages of quiet and recurrent activity and less unclear activity. These percentages are similar to those in solar cycles observed in the late 1800s. Since 1963, solar wind data are available. We analyze the distribution of the solar wind velocity for each geomagnetic class of activity and find that: 1) Within each activity type aa does not depend on V, 2) Approximately 80% of the solar wind has V < 450 km/s for QA and 80% of the solar wind has V > 450 km/s for RA, 3) SA and UA both have 60% of the solar wind V > 450 km/s. We found the following conditions for all four solar cycles: 1) For QA 95% of solar wind speeds are in the range 399 ± 69 km/s, 2) For RA 95% of the solar wind speeds range from 582 ± 110 km/s, 3) For SA 95% of the solar wind velocities are order of 482 ± 101.4 km/s, and 4) For UA 95% of solar wind speeds are 480 ± 85.82 km/s. These results confirm the classification scheme that QA reflects slow wind effects, RA effects high wind stream and UA answers

Wind-Solar Hybrid Electrical Power Production to Support National Grid: Case Study - Jordan  [PDF]
Ghassan HALASA, Johnson A. ASUMADU
Energy and Power Engineering (EPE) , 2009, DOI: 10.4236/epe.2009.12011
Abstract: The paper presents the next generation of power energy systems using solar- and wind-energy systems for the country of Jordan. Presently with the oil prices are on the rise, the cost of electrical power production is very high. The opportunity of a large wind and solar hybrid power production is being explored. Sights are chosen to produce electricity using the wind in the Mountains in Northern Jordan and the sun in the Eastern Desert. It is found that the cost of windmill farm to produce 100 - 150 MW is US$290 million while solar power station to produce 100 MW costs US$560 million. The electrical power costs US$0.02/kWh for the wind power and US$0.077 for the solar power. The feasibility for using wind and solar energies is now when the price oil reaches US$ 100.00 per barrel. The paper also discusses different power electronics circuits and control methods to link the renewable energy to the national grid. This paper also looks at some of the modern power electronics converters and electrical generators, which have improved significantly solar and wind energy technologies.
On the Predictive Ability of Geomagnetic Disturbances from Solar Wind Measurements at Separated Solar Longitude  [PDF]
Wataru Miyake, Tsutomu Nagatsuma
International Journal of Astronomy and Astrophysics (IJAA) , 2012, DOI: 10.4236/ijaa.2012.22009
Abstract: In-situ solar wind measurement at a solar longitude separated from the earth in interplanetary space is expected to provide a great progress in practical space weather forecast, which has been confirmed by some recent studies. We introduce geoeffective solar wind conditions in correlation analysis between STEREO and ACE measurements. We sort solar wind data of ACE by using geomagnetic condition, and evaluate actual ability for predicting geoeffective solar wind arrival at ACE from STEREO-A and B solar wind measurement, by assuming simple corotating structures in interplanetary space. The results show that geomagnetic disturbances are more difficult to be predicted than quiet intervals, suggesting that the simple correlation method of solar wind measurement at separated solar longitude is not enough for accurately predicting geomagnetic disturbances, even though the correlation seems generally high. Although in-situ solar wind monitoring at a vantage point trailing behind the earth would definitely improve the prediction capability of solar wind structure arriving at the terrestrial plasma environment, we emphasize that the predictive ability of geoeffective disturbances would still remain low. We suggest that more sophisticated prediction schemes should be developed.
Cost and Emissions Implications of Coupling Wind and Solar Power  [PDF]
Seth Blumsack, Kelsey Richardson
Smart Grid and Renewable Energy (SGRE) , 2012, DOI: 10.4236/sgre.2012.34041
Abstract: We assess the implications on long-run average energy production costs and emissions of CO2 and some criteria pollutants from coupling wind, solar and natural gas generation sources. We utilize five-minute meteorological data from a US location that has been estimated to have both high-quality wind and solar resources, to simulate production of a coupled generation system that produces a constant amount of electric energy. The natural gas turbine is utilized to provide fill-in energy for the coupled wind/solar system, and is compared to a base case where the gas turbine produces a constant power output. We assess the impacts on variability of coupled wind and solar over multiple time scales, and compare this variability with regional demand in a nearby load center, and find that coupling wind and solar does decrease variability of output. The cost analysis found that wind energy with gas back-up has a lower levelized cost of energy than using gas energy alone, resulting in production savings. Adding solar energy to the coupled system increases levelized cost of energy production; this cost is not made up by any reductions in emissions costs.
Feasibility Analysis of Constructing Solar Power Plant by Combining Large Scale Wind Farm  [PDF]
Mingzhi Zhao, Yanling Zhang, Shijin Song, Xiaoming Zhang
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B017
Abstract: Hybrid utilization of renewable energy is one of effective method which can solve the problem that unstable of renewable energy so as not to substitute traditional fossil energy. As the typical renewable energy, solar energy and wind energy are in the van of renewable energy utilization. With the large scale utilization of solar and wind energy in the world, constructing large scale solar power plant in the large scale wind farm can make the most of ground resource combining the wind energy with solar energy. Feasibility of constructing large scale solar power plant in the large scale wind farm was analyzed in this paper, and come to a conclusion that constructing large scale solar power plant in the large scale wind farm can not also achieved the goal of mutual support of resource advantages and economizing money but also improved significantly the seasonal mismatch by combining solar with wind.
Improving the Power Generation Performance of a Solar Tower Using Thermal Updraft Wind  [PDF]
Masataka Motoyama, Kenichiro Sugitani, Yuji Ohya, Takashi Karasudani, Tomoyuki Nagai, Shinsuke Okada
Energy and Power Engineering (EPE) , 2014, DOI: 10.4236/epe.2014.611031
Abstract: The purpose of this study is to improve the efficiency of the power generation system of a solar tower using fluid dynamics. The power generation system of a solar tower can be designed and constructed at relatively low cost. However, the energy output tends to be low for its physical size compared with other renewable energy production systems. The technical and scientific improvement of these types of generation systems has lost its momentum since the shutdown of the wellknown Spanish pilot plant “Manzanares Solar Chimney” in 1989, although it still has the potential to play a role in renewable energy in the future. We have focused on the tower component of the system to seek possible enhancements of the power output of the internal turbine. As a result of our fluid dynamic shape optimization, a diffuser-shaped tower was employed to increase the internal flow speed of a scaled model. The results show a remarkable improvement in the power output of the internal wind turbine.
Erratum to “Improving the Power Generation Performance of a Solar Tower Using Thermal Updraft Wind” [Energy and Power Engineering Vol. 6 No. 11 (October 2014) 362-370]  [PDF]
Masataka Motoyama, Yuji Ohya, Takashi Karasudani, Tomoyuki Nagai, Shinsuke Okada, Kenichiro Sugitani
Energy and Power Engineering (EPE) , 2015, DOI: 10.4236/epe.2015.76024
Abstract: The original online version of this article (Masataka Motoyama, Kenichiro Sugitani, Yuji Ohya, et al. (2014) “Improving the Power Generation Performance of a Solar Tower Using Thermal Updraft Wind”, 2014, 6, 362-370. http://dx.doi.org/10.4236/epe.2014.611031) was published in October, 2014.The author wishes to correct the following error in text and Figures 9-11.
Multi-scale pressure-balanced structures in the solar wind observed by WIND
Shuo Yao,ChuanYi Tu,JianSen He,WenBo Wei,XiaoHong Meng
Chinese Science Bulletin , 2012, DOI: 10.1007/s11434-011-4966-1
Abstract: This work detects multi-scale, from hour to seconds, pressure-balanced structures (PBSs) in the solar wind based on the anti-correlation between the plasma thermal pressure and the magnetic pressure measured by WIND at 1 AU on April 5th, 2001. In our former research based on Cluster measurements, we showed the anti-correlation between the electron density and the magnetic field strength in multi-scales, and we supposed these structures may be pressure-balanced structures. Thus, in this work we aim to prove our speculation by the direct evidence on pressure measurements. Different from our previous work, we apply the WIND measurements this time, for they have both the magnetic pressure and the plasma pressure which Cluster could not offer. We use the wavelet cross-coherence method to analyze the correlation between the plasma pressure (P th ) and the magnetic pressure (P B ), and also the electron density (N e ) and the magnetic field strength (B) on various scales. We observe the anti-correlation between P th and P B distributed at different temporal scales ranging from 1000 s down to 10 s. This result directly indicates the existence of pressure-balanced structures (PBSs) with different sizes in the solar wind. Further, We compare the wavelet cross correlation spectrum of P th -P B and N e -B. We notice that the two spectra are similar in general. Thus this result confirms that the relation between P th -P B and N e -B are consistent with each other in the PBSs we study. Moreover, we compare the power spectrum density (PSD) of relative N e fluctuation with our previous work based on Cluster measurements. The two spectra show similar trend with Komolgorov’s 5/3 as their slopes. This may imply the similarity of the structures observed by both WIND and Cluster spacecrafts. Finally, we discuss the possible formation mechanisms for these multi-scale pressure-balanced structures. Our result is important to support the existence of multi-scale PBSs from one-hour scale down to one-minute, and is helpful to understand the role of compressive fluctuation in the solar wind turbulence dominated by Alfvéenic cascading.
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