FUN WITH THE SUNA NEW WORLD INITIATIVE

Published By : Jyotsana Rastogi: Saransh Gupta

Our Area Of Interest

From eons, man has searched for a viablesource of energy. The invention of fossil fuelat one time was a matter of much awe.However, soon the need for better alternatives was felt.

From fossil fuels to the renewable sources of energy such as solar, hydro, wind,etc. the advancements have been great. And now, its the call of this very age of advancement which directs our mind to the ambitious project of harnessing

energy in the space.

Why Space??

Space offers some very attractive ways of harnessing energy such as by the usage of helium – 3, windmills on mars ,recently may be from methane on mars, etc. Space has asteroids, plasma etc. Boasting of some unique properties which make it an even betteroption than Earth for the purpose of harnessing energy. Harnessing solar energy in space, we think, will be one of the most ground-breaking inventions of the 21st century, as well as being the most viable.Our model for the same contains ideas from a exhaustive study of the existing models,the proposed models, journals by acclaimed scientists as well as innovative and unique ideas of my teammate!

Had Enough of empty words??

This is how we turn our empty wordsinto reality..

The journey to the space for harnessing solar energy begins by launching a rocket consisting of a setup of two consecutiveidentical parabolic mirrors having common centre of curvatures

and the solar panels placed at the centre of curvature to extract maximum solar energy. When parallel rays are incident on parabolic surface they converge the incident rays to the centre of curvature with maximum intensity. The rocket containing this setup consists of three parts which are combined together as a single unit at a time of launching the rocket. Further the rocket is launched in the space after which two of its subunit get detached and only the topmost part containing solar panel and parabolic mirror gets in to the outer space as this topmost part reaches the space the setup opens rotating around the earth similar to the way as satellites revolve around the earth. Now the solar energy received by the solar panels is converted to microwave energy which is further transmitted to earth. While travelling towards the earth, the microwaves are converged towards the tiny retinas using transceivers. Further, the microwave energy received by the rectenna is converted to dc voltage ,then to ac. And hence using energy from space we produced electricity.

Comes the Sun: Mirrors in orbit would reflect sunlight onto huge solar panels, and the resulting power would be beamed down to Earth.

But you have not seen the most interesting part .Several giant solar collectors in geosynchronous orbit would be beaming microwaves down to

the bay (island) from 36,000 km above Earth.

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On Microwaves and Lasers

• The laser method’s main advantages and disadvantages both relate to its short wavelength, which would be around 1 micrometer for this application. Such wavelengths can be transmitted and received by relatively small components: The transmitting optics in space would measure about 1 meter for a 1-GW installation, and the receiving station on the ground would be several hundred meters long. However, the short-wavelength laser would often be blocked by the atmosphere; water molecules in clouds would absorb or scatter the laser beam, as they do sunlight. No one wants a space-based solar power system that works only when the sky is clear.

• But microwaves—for example, ones with wavelengths between 5 and 10 centimetres—would have no such problems in transmission. Microwaves also have an efficiency advantage for a space-based solar power system, where power must be converted twice: first from DC power to microwaves aboard the satellite, then from microwaves to DC power on the ground. In lab conditions, researchers have achieved about 80 percent efficiency in that power conversion on both ends. Electronics companies are now striving to achieve such rates in commercially available components, such as in power amplifiers based on gallium nitride semiconductors, which could be used in the microwave transmitters.

Carbon Rules!!!

Today, researchers are experimenting with adding a small amount of grapheneflakes to polymer-blend bulk-heterojunction (BHJ) solar cells and are finding that it improves the conversion efficiency of the cells significantly. The semiconducting part of a BHJ solar cells is made from two different materials—an electron donor and an acceptor. Light forms exactions at their interface, which separate into holes and the electrons producing a voltage. In the work performed , they have discovered that they can increase the ratio of electron donors to electron acceptors to boost the energy absorbed by the cell.Because graphene is pure carbon, its charge conductivity is very high. We want to maximize the energy being absorbed by the solar cell, so we will increase the ratio of the donor to acceptor and we will use a very low fraction of graphene to achieve the goal.

Special arrangement of recteenas and transrecivers to extract maximum of microwave energy and convert it to

electrical energy

Parabolic mirrors convergingsolar energy.

a more advanced SPS concept that solves the solar collection problem by employing two huge reflective mirrors accompanied with Sensors and controllers. These would be

positioned so that between the two of them, they would direct light onto two photovoltaic panels 24 hours a day. The two mirrors would be free flying, not tethered to the solar panels

or the separate transmission unit, which means that we would have to master a sophisticated kind of formation flying to implement this system

In space there is 10 times as much available solar energy as on Earth: There are no efficiencyreductions due to the day-night cycle, seasonal

variation, or weather conditions.

Recteena : An Introduction

Rectenna is actually an abbreviation i.e. rectifying antenna which is a device that receives microwaves & then converts it into D.C.We can in fact directly convert solar energy into electrical energy with the use of solar cells, but sunlight diffuses in the night time from the earth. And if the need arises for 24 hrs Power supply, the most directive solution is rectinna. We are aware of the fact that light is an electromagnetic wave. Light rays never diffuse in space & if by any means these rays can be transmitted from space to earth then it will be a nice solution for our desired need of 24 hrs power supply. An SPS (Space Power Satellite) will convert the light rays to microwaves & will transmit them to earth. The main component is schottky dioode.Rectifying antenna rectifies received microwaves into DC current. A rectenna comprises of a mesh of dipoles and diodes for absorbing microwave energy from a transmitter and converting it into electric power. Its elements are usually arranged in a mesh pattern, giving it a distinct appearance from most antennae .

A simple rectenna can be constructed from a schottky diode placed between antenna dipole. The diode rectifies the current induced in the antenna by the microwaves. Rectennae are highly efficient at converting microwave energy to

electricity. In laboratory environments, efficiencies above 90% have been observed with regularity. In future rectennas will be used to generate large scale power from microwave beams delivered from orbiting SPS satellites.

Now actually what we are thinking here is to use the beam energy falling on the 3km wide surface such that we could achieve maxium power at

maximum efficiency. For this purpose a synchrotron can be used.Let us discuss what basically a synchrotron is??

A synchrotron is an extremely powerful source of X-rays. These are produced by highly energetic electrons moving in a large circle

in the synchrotron.The entire world of synchrotron science depends on one physical phenomenon: When a moving electron

changes direction, it emits energy. When the electron is moving fast enough, the emitted energy is at X-ray wavelength.A synchrotron

machine exists to accelerate electrons to extremely high energy and then make them change direction periodically. The resulting X-rays

are emitted as dozens of thin beams, each directed toward a beamline next to the accelerator, so the energy of these beamed x-

rays that are accelerated to higher potentials could generate enormous power feasibly. The entire beam energy that is beamed to earth after going thorugh a panel of rectennas could be used to accelerate these electrons or some micoparticles that could make

the structure efficient and cost effective and an alternative to rectennas.

Future perspective & cost analysis

• The land below the rectenna can be utilized for domestic purposes like farming etc,apart from this if the rectennas are generating any kind of heat energy then it can be easily utilized as a steam for thermal power plant. We can provide water as a coolant as we have large amount of water on earth.

• The procedure involed in the projects would be difficult and expensive, but the payoff would be immense, and not just in economic terms. Throughout human history, the introduction of each new energy source—beginning with firewood, and moving on through coal, oil, gas, and nuclear power—has caused a revolution in our way of living. If humanity truly embraces space-based solar power, a ring of satellites in orbit could provide nearly unlimited energy, ending the biggest conflicts over Earth’s energy resources. As we place more of the machinery of daily life in space, we’ll begin to create a prosperous and peaceful civilization beyond Earth’s surface.

Conclusion

In space there is 10 times as much available solar energy as on Earth: There are no efficiency reductions due to the day-night cycle, seasonal variation, or weather conditions.

Once the station is installed, the imbursement will be enormous because in space there is 10 times as much available solar energy as on Earth. There will be no efficiency reductions due to the day-night

cycle, seasonal variation, or weather conditions. The space-based solar collectors in geosynchronous orbit will be able to generate power nearly 24 hours a day. Our replacement over

silicon solar cells by graphene and CNTs will anonymous. Graphene is characterized as lighter than a feather, stronger than steel, incredibly flexible and more conductive than copper. These

characteristics give our project a major support. With the use of oscillators the power is sent from the space using microwaves

which have high operating frequencies, require small antennas, reliable and hence require less maintenance.

These microwaves are received 36,000 kms below on the earth by the rectenna and cyclotron wave converters. These are not only efficient and feasible but also eco-friendly. They convert microwaves

in to ac supply which can be used further.In our project we have not only emphasized on the efficiency and feasibility of our work but we have

also shared our concern regarding our environment and for the people who are living on it. At the end we would like to end up saying..”Sunlight will soon be a source which will be nurturing us in

every aspect with its immense amount of energy and all the problems of power will vanish away and simultaneously compelling all the human race to afford their gratitude to the Creator !!!!”