scholarly journals How Can We Use Ocean Energy to Generate Electricity?

2021 ◽  
Vol 9 ◽  
Author(s):  
M. Luisa Martínez ◽  
Rodolfo Silva ◽  
Janaina Garcia
Keyword(s):  
Water Temperature ◽  
Electric Power ◽  
The Sun ◽  
The Moon ◽  
Ocean Energy ◽  
Waves And Tides ◽  
The Waves

The oceans represent almost 70% of the surface of our planet, and they are in constant movement through waves, tides, and currents. These movements are formed differently: waves develop because of the action of the wind; tides because of the moon and the sun, and currents because of differences in water temperature and the rotation of the planet. Ocean movements bring food and oxygen to the plants and animals that live in the oceans and on the coasts. Waves and tides also help shape the coastline by erosion and accumulation of sand. Ocean movement is also important for humans: we have fun swimming in the waves, the tides help with fishing, and the currents are useful for moving ships across the ocean. This unending movement of the ocean can also be used to produce clean, renewable electric power.

scholarly journals Wave and tidal energy: the potential for extraction of sustainable energy from the ocean

2014 ◽  
Vol 126 (2) ◽  
pp. 34
Author(s):  
Timothy D. Finnigan
Keyword(s):  
Renewable Energy ◽  
Surface Waves ◽  
Energy Demand ◽  
Fossil Fuels ◽  
Tidal Energy ◽  
Thermal Gradients ◽  
The Sun ◽  
The Moon ◽  
Ocean Energy ◽  
Global Population

The ocean represents an enormous store of renewable energy – far more than could ever be used by the global population. The challenge is: how do we go about extracting this energy in a sustainable and economical way? It is the sun and the moon that give us this energy, in the form of waves, tides and thermal gradients. The amount of energy stored in the ocean, and continually replenished by the sun and moon, is well quantified, and certifiably massive. Despite decades of effort, attempts to extract meaningful quantities of energy from these ocean sources continue to be met with monumental challenges. Given the anticipated growth in energy demand, and continuing concern with the use of fossil fuels, it is now time to push through the barriers. The most widespread and easily tapped sources of ocean energy are surface waves and tidal currents. This presentation will focus on these two sources only.

scholarly journals Emission of Gravitational Waves from a Magnetohydrodynamic Dynamo in the Center of the Sun

2015 ◽  
Vol 70 (7) ◽  
pp. 545-551
Author(s):  
Friedwardt Winterberg
Keyword(s):  
Magnetic Field ◽  
Gravitational Waves ◽  
Main Sequence ◽  
Fusion Reaction ◽  
Large Mass ◽  
The Sun ◽  
The Moon ◽  
Convection Pattern ◽  
Main Sequence Stars ◽  
The Waves

AbstractBy Birkhoff’s theorem a spherical symmetric convection pattern, as it is assumed to exist for main sequence stars as our sun, cannot lead to the emission of gravitational waves, but all stars that have a magnetic field generated by a magnetohydrodynamic dynamo must by a theorem of Cowling have a non-spherical symmetric convections pattern and for this reason have to emit gravitational waves. The intensity of the thusly emitted gravitational waves depends on the efficiency of this dynamo, expressed by the departure from a spherical convection pattern. The magnitude of the asymmetry is determined by a solution of Elsaesser’s dynamo equations which only recently has become possible with supercomputers. The waves are emitted through large mass motions in the center of the sun by a thermonuclear fusion reaction-driven magnetohydrodynamic dynamo, with thermomagnetic currents in the tachocline shielding the strong magnetic field in the solar core. Using the moon as a large Weber bar, the gravitational waves are focused into the lunar shadow by Poisson diffraction where their effect might become observable during a total solar eclipse.

scholarly journals Harnessing Ocean Energy from Coastal and Offshore Pakistan

2022 ◽  
Vol 12 (1) ◽  
pp. 78
Author(s):  
Shahid Amjad
Keyword(s):  
Thermal Energy ◽  
Fossil Fuels ◽  
Incident Radiation ◽  
Working Fluid ◽  
The Sun ◽  
Energy Extraction ◽  
Ocean Energy ◽  
Coastal Waves ◽  
Waves And Tides ◽  
Ocean Thermal Energy

There is potential for harnessing renewable energy from coastal waves and tides, from the coastal and offshore areas of Pakistan. The Sindh coast is a complex creek network located in the 170 km of the Indus deltaic area. The flood and ebb of tides in and out of these creeks have a high velocity of 0.2–0.5 m/s. NIO Pakistan has conducted preliminary feasibility surveys for energy extraction from the Indus deltaic creek system. The 17 major creeks have the capacity to produce estimated energy of approximately 1100 MW. The seawater ingresses inland at some places up to 80 km due to the tidal fluctuation, which is favorable for energy extraction from tidal currents in coastal Sindh. In total, 71% of our Planet Earth is covered by the oceans. The oceans are massive collectors of solar radiation received from the sun. The oceans store the potential energy that is received in the form of incident radiation from the sun that generates thermal energy. A 10 °C temperature difference can be harnessed between the surface and bottom water, using a working fluid. The thermal difference absorbed by the oceans can be converted into electricity through ocean thermal energy conversion (OTEC). The ocean tidal and wave energy has advantages over energy produced using different fossil fuels; there are also several benefits of using renewable sources of ocean energy. Viability of ocean energy in Pakistan is discussed in this paper.

Modelling Lunar Extremes

2018 ◽  
Vol 3 (2) ◽  
pp. 207-216 ◽  
Author(s):  
David Fisher ◽  
Lionel Sims
Keyword(s):  
High Precision ◽  
Celestial Mechanics ◽  
Computer Modelling ◽  
Landscape Context ◽  
The Sun ◽  
The Moon

Claims first made over half a century ago that certain prehistoric monuments utilised high-precision alignments on the horizon risings and settings of the Sun and the Moon have recently resurfaced. While archaeoastronomy early on retreated from these claims, as a way to preserve the discipline in an academic boundary dispute, it did so without a rigorous examination of Thom’s concept of a “lunar standstill”. Gough’s uncritical resurrection of Thom’s usage of the term provides a long-overdue opportunity for the discipline to correct this slippage. Gough (2013), in keeping with Thom (1971), claims that certain standing stones and short stone rows point to distant horizon features which allow high-precision alignments on the risings and settings of the Sun and the Moon dating from about 1700 BC. To assist archaeoastronomy in breaking out of its interpretive rut and from “going round in circles” (Ruggles 2011), this paper evaluates the validity of this claim. Through computer modelling, the celestial mechanics of horizon alignments are here explored in their landscape context with a view to testing the very possibility of high-precision alignments to the lunar extremes. It is found that, due to the motion of the Moon on the horizon, only low-precision alignments are feasible, which would seem to indicate that the properties of lunar standstills could not have included high-precision markers for prehistoric megalith builders.

Sweat of the Sun and Tears of the Moon. Gold and Silver in Pre-Columbian Art

1967 ◽  
Vol 71 (2) ◽  
pp. 215
Author(s):  
Earle R. Caley ◽  
Andre Emmerich
Keyword(s):  
The Sun ◽  
The Moon

scholarly journals How dim is dim? Precision of the celestial compass in moonlight and sunlight

2011 ◽  
Vol 366 (1565) ◽  
pp. 697-702 ◽  
Author(s):  
M. Dacke ◽  
M. J. Byrne ◽  
E. Baird ◽  
C. H. Scholtz ◽  
E. J. Warrant
Keyword(s):  
Dung Beetle ◽  
The Sun ◽  
The Moon ◽  
Polarization Pattern ◽  
Animal Group ◽  
Straight Line ◽  
Celestial Orientation ◽  
Polarization Compass ◽  
Celestial Compass ◽  
Diurnal Species

Prominent in the sky, but not visible to humans, is a pattern of polarized skylight formed around both the Sun and the Moon. Dung beetles are, at present, the only animal group known to use the much dimmer polarization pattern formed around the Moon as a compass cue for maintaining travel direction. However, the Moon is not visible every night and the intensity of the celestial polarization pattern gradually declines as the Moon wanes. Therefore, for nocturnal orientation on all moonlit nights, the absolute sensitivity of the dung beetle's polarization detector may limit the precision of this behaviour. To test this, we studied the straight-line foraging behaviour of the nocturnal ball-rolling dung beetle Scarabaeus satyrus to establish when the Moon is too dim—and the polarization pattern too weak—to provide a reliable cue for orientation. Our results show that celestial orientation is as accurate during crescent Moon as it is during full Moon. Moreover, this orientation accuracy is equal to that measured for diurnal species that orient under the 100 million times brighter polarization pattern formed around the Sun. This indicates that, in nocturnal species, the sensitivity of the optical polarization compass can be greatly increased without any loss of precision.

scholarly journals Astronomy at the service of the Islamic society

2009 ◽  
Vol 5 (S260) ◽  
pp. 514-521
Author(s):  
Ilias M. Fernini
Keyword(s):  
Proper Time ◽  
Astronomical Observatory ◽  
The Sun ◽  
The Moon ◽  
Scientific Institutions ◽  
Mathematical Astronomy ◽  
Islamic Empire ◽  
New Moon ◽  
Islamic Society

AbstractThe Islamic society has great ties to astronomy. Its main religious customs (start of the Islamic month, direction of prayer, and the five daily prayers) are all related to two main celestial objects: the Sun and the Moon. First, the start of any Islamic month is related to the actual seeing of the young crescent after the new Moon. Second, the direction of prayer, i.e., praying towards Mecca, is related to the determination of the zenith point in Mecca. Third, the proper time for the five daily prayers is related to the motion of the Sun. Everyone in the society is directly concerned by these customs. This is to say that the major impetus for the growth of Islamic astronomy came from these three main religious observances which presented an assortment of problems in mathematical astronomy. To observe these three customs, a new set of astronomical observations were needed and this helped the development of the Islamic observatory. There is a claim that it was first in Islam that the astronomical observatory came into real existence. The Islamic observatory was a product of needs and values interwoven into the Islamic society and culture. It is also considered as a true representative and an integral par of the Islamic civilisation. Since astronomy interested not only men of science, but also the rulers of the Islamic empire, several observatories have flourished. The observatories of Baghdad, Cairo, Córdoba, Toledo, Maragha, Samarqand and Istanbul acquired a worldwide reputation throughout the centuries. This paper will discuss the two most important observatories (Maragha and Samarqand) in terms of their instruments and discoveries that contributed to the establishment of these scientific institutions.

scholarly journals XLIV. Variation of the compass, as observed on board the Endeavour Bark, in a voyage round the World

1771 ◽  
Vol 61 ◽  
pp. 422-432 ◽  
Keyword(s):  
The Sun ◽  
The Moon ◽  
The World

The day of the month is noted according to the nautical account, which therefore in all observations noted P. M. is one day forwarder than the civil account. The latitude in is deduced from the last preceding meridian altitude of the Sun; and the longitude in is corrected by the last observations of the distances of the moon from the Sun and stars.

Sign in / Sign up

Export Citation Format

Share Document