Sattellite Power Station1

R.K.PradhanR.K.Pradhan 1110:24 AM10:24 AM

Satellite Power StationSatellite Power Station and and

Microwave Power Microwave Power TransmissionTransmission

Presented by-Presented by-______________________________________________

______________________________________

______________________

________________

10:24 AM10:24 AM R.K.PradhanR.K.Pradhan 22

OutlineOutline

• IntroductionIntroduction

• Basic ConceptBasic Concept

• Solar Power SatelliteSolar Power Satellite

• Microwave Power TransmissionMicrowave Power Transmission

• SPS 2000SPS 2000

• Issues InvolvedIssues Involved

• ConclusionConclusion


IntroductionIntroduction• The demand for energy worldwide has

increasing by 100% or almost doubled in every decade.

• The world’s main source of power is still generated by fossil fuels which is limited

(85% of the total power globally).• Harmful effects of hydrocarbon-based

power sources to environment. • Regional political and religious conflicts

can disrupt world-wide distribution of fossil fuel.


Basic ConceptBasic Concept

• Solar Power Satellites providing a Solar Power Satellites providing a better way of power generationbetter way of power generation

• Transmission of power to earth via Transmission of power to earth via microwavesmicrowaves

• Collection of power by specially Collection of power by specially developed antennas (rectennas)developed antennas (rectennas)


SOLAR POWER SOLAR POWER SATELLITESSATELLITES

Solar Power SatelliteSolar Power Satellite or or SPSSPS, is a , is a proposed satellite built in proposed satellite built in geostationary orbit that uses geostationary orbit that uses microwave power transmission to microwave power transmission to beam power to a very large antenna beam power to a very large antenna on Earth where it can be used in on Earth where it can be used in place of conventional power sources. place of conventional power sources.


Basic componentsBasic components

• A huge solar collector, typically A huge solar collector, typically made of solar cells.made of solar cells.

• D.C. to Microwave conversion D.C. to Microwave conversion through magnetron.through magnetron.

• Transmitting antenna sub array on Transmitting antenna sub array on the satellite, aimed at earth.the satellite, aimed at earth.


Magnetron OperationMagnetron Operation


Continued…Continued…


Reference systemReference system


DOE (US) StudyDOE (US) Study

• Construct the satellites in spaceConstruct the satellites in space– Each SPS would have 400 million solar cellsEach SPS would have 400 million solar cells

• Use the Heavy Lift Launch Vehicle (HLLV) to Use the Heavy Lift Launch Vehicle (HLLV) to get Solar Sailing Array Panels (SSAP) to a get Solar Sailing Array Panels (SSAP) to a Low Earth Orbit (LEO)Low Earth Orbit (LEO)

• Tow pieces to the assembly point (GEO) Tow pieces to the assembly point (GEO) using ion thruster mechanism powered by using ion thruster mechanism powered by the solar energy obtained from solar panelsthe solar energy obtained from solar panels

• Integration into SPS by telerobotics Integration into SPS by telerobotics


Heavy Lift Launch VehiclesHeavy Lift Launch Vehicles


Advantages over Earth Advantages over Earth based solar powerbased solar power• More intense sunlightMore intense sunlight• In geosynchronous orbit, 36,000 km In geosynchronous orbit, 36,000 km

(22,369 miles) an SPS would be (22,369 miles) an SPS would be illuminated over 99% of the timeilluminated over 99% of the time

• Power can be beamed to any location Power can be beamed to any location where it is desired.where it is desired.

• No air or water pollution is created No air or water pollution is created during generation during generation


SpecificationsSpecifications

1.1. Satellite antenna must be between 1 and Satellite antenna must be between 1 and 1.5 kilometers in diameter and the ground 1.5 kilometers in diameter and the ground rectenna around 14 kilometers by 10 rectenna around 14 kilometers by 10 kilometers .kilometers .

2.2. Collector area must be between 50 (19 sq Collector area must be between 50 (19 sq miles) and 150 square kilometers (57 sq miles) and 150 square kilometers (57 sq miles)miles)

3.3. 50 Tons of material50 Tons of material– Current rates on the Space Shuttle run Current rates on the Space Shuttle run

between $3500 and $5000 per poundbetween $3500 and $5000 per pound– 50 tons (112,000lbs)=$392,000,00050 tons (112,000lbs)=$392,000,000



4.4. Possible power generation of 5 to 10 Possible power generation of 5 to 10 Gigawatts Gigawatts– ““If the largest conceivable space power If the largest conceivable space power

station were built and operated 24 hours station were built and operated 24 hours a day all year round, it could produce a day all year round, it could produce the equivalent output of ten 1 million the equivalent output of ten 1 million kilowatt-class nuclear power stations.”kilowatt-class nuclear power stations.”


Possible DesignsPossible Designs


Deployment IssuesDeployment Issues

• Cost of transporting materials into Cost of transporting materials into spacespace

• Construction of SSAPConstruction of SSAP– Space WalksSpace Walks

• MaintenanceMaintenance– Routine checkupRoutine checkup– Meteor impactsMeteor impacts

R.K.PradhanR.K.Pradhan 202010:24 AM10:24 AM

Microwave Power Microwave Power TransmissionTransmission

How the power gets to Earth?How the power gets to Earth?


From the SatelliteFrom the Satellite

•Power from the satellite is sent Power from the satellite is sent to Earth using a microwave to Earth using a microwave transmittertransmitter

•The beamed power is received The beamed power is received through “rectenna” located at a through “rectenna” located at a place on Earthplace on Earth


Microwave TransmissionMicrowave Transmission

1.1. Frequency 2.45 GHz microwave beamFrequency 2.45 GHz microwave beam

2.2. Beamed Power level is well below Beamed Power level is well below lethal levels of concentration even for lethal levels of concentration even for prolonged exposureprolonged exposure

3.3. High efficiency up to 85%High efficiency up to 85%

4.4. Cause interference with Cause interference with communication satellitescommunication satellites

5.5. Safety ensured for flying bodies to Safety ensured for flying bodies to greater extent.greater extent.


RectennaRectenna““An antenna comprising a mesh of dipoles An antenna comprising a mesh of dipoles

and diodes for absorbing microwave and diodes for absorbing microwave energy from a transmitter and converting it energy from a transmitter and converting it by rectification into D.C. power.” by rectification into D.C. power.”

•Microwaves are received with Microwaves are received with about 85% efficiencyabout 85% efficiency

•95% of the beam will fall on the 95% of the beam will fall on the rectennarectenna


Basic block diagramBasic block diagram


Power captured by rectennaPower captured by rectenna

• The voltage at the terminal of rectenna The voltage at the terminal of rectenna is equal to the electric field times the is equal to the electric field times the effective length. effective length.

VVTT =El =El

• Half of the power captured is scattered Half of the power captured is scattered back and half is delivered to the load.back and half is delivered to the load.

PPTT = = VVTT22 /4R /4RTT


RectificationRectification• The conversion from A.C. to D.C. by means The conversion from A.C. to D.C. by means

of rectifying device.of rectifying device.• Types of rectification schemes.Types of rectification schemes. -half wave -half wave -full wave-full wave• The expected overall rectification The expected overall rectification

efficiency,efficiency,

ηηcc=dc output power/rf incident power=dc output power/rf incident power• The obtained conversion efficiency due to The obtained conversion efficiency due to

mismatch,mismatch,

ηηcc=dc output power/=dc output power/ (rf incident power-rf reflected power)(rf incident power-rf reflected power)


Full-Wave Vs Half-Wave Full-Wave Vs Half-Wave RectificationRectification

• Why full wave Why full wave rectification?rectification?

-Large V-Large Vminmin

-Smaller ripple factor-Smaller ripple factor

• Full wave rectification Full wave rectification by two diodes.by two diodes.

• Diode’s inputs 180 Diode’s inputs 180 degrees out of phase.degrees out of phase.


Rectenna’s method of Rectenna’s method of InterconnectionInterconnection

•Solar rectenna’s model.

•Series connection.

•Parallel Connection.

•Hybrid Connection.


Solar Rectenna’s modelSolar Rectenna’s model


Hybrid connections Hybrid connections


Rectenna DesignRectenna Design

• Currently there are two different design Currently there are two different design types being looked attypes being looked at– Wire mesh reflectorWire mesh reflector

•Built on a rigid frame above the Built on a rigid frame above the groundground

•Visually transparent so that it would Visually transparent so that it would not interfere with plant lifenot interfere with plant life

– Magic carpetMagic carpet•Material pegged to the groundMaterial pegged to the ground


Wire mesh reflectorWire mesh reflector


Magic carpetMagic carpet


Rectenna IssuesRectenna Issues• SizeSize

– Miles acrossMiles across• LocationLocation

– AestheticAesthetic– Near population centerNear population center

• Health and environmental side effectsHealth and environmental side effects– Although claim that microwaves would Although claim that microwaves would

be safe, how do you convince peoplebe safe, how do you convince people


SPS 2000SPS 2000


Working model of Japanese Working model of Japanese Space Solar Power Plant Space Solar Power Plant SPS2000 in Sagamihara, Japan.SPS2000 in Sagamihara, Japan.


Design FeaturesDesign Features•LEO satellite: Approx. 1000Km LEO satellite: Approx. 1000Km

altitude to reduce launch costs and altitude to reduce launch costs and to minimize size of transmitting to minimize size of transmitting antenna.antenna.

•Power output: Ranging from 5GW Power output: Ranging from 5GW to 10GWto 10GW

•Microwave beam footprints: Microwave beam footprints: ground footprint of 3Km in ground footprint of 3Km in diameter and transmitting antenna diameter and transmitting antenna of 100m in diameter.of 100m in diameter.



• 5-10 GW satellite delivering 5-10 GW satellite delivering microwave powermicrowave power– Will not be in geosynchronous orbit, Will not be in geosynchronous orbit,

instead low orbit 1000 km instead low orbit 1000 km – Much cheaper to put a satellite in Much cheaper to put a satellite in

low orbitlow orbit– 200 seconds of power on each pass 200 seconds of power on each pass

over rectennaover rectenna


Microwave Beam FootprintMicrowave Beam Footprint


Low OrbitLow Orbit• Proposed to have hundreds of Proposed to have hundreds of

satellites in low earth orbit satellites in low earth orbit • Since a low orbit microwave beam Since a low orbit microwave beam

would spread less, the ground based would spread less, the ground based rectenna could be smaller i.e. in the rectenna could be smaller i.e. in the range of few hundred meters across range of few hundred meters across instead of 10 kilometers.instead of 10 kilometers.

• In low orbit they circle the Earth in In low orbit they circle the Earth in about every 90 minutesabout every 90 minutes


Constructional design of SPSConstructional design of SPS


ReliabilityReliability• Ground based solar Ground based solar

only works during only works during clear days, and clear days, and must have storage must have storage for nightfor night

• Power can be Power can be beamed to the beamed to the location where it is location where it is neededneeded

• A network of low A network of low orbit satellites orbit satellites could provide could provide power to almost power to almost any point on Earth any point on Earth continuously continuously because one because one satellite would satellite would always be in rangealways be in range


IssuesIssues Involved Involved• Motivation towards improved Motivation towards improved

technology and economic benefits.technology and economic benefits.

• Effect of long term exposure to Effect of long term exposure to microwavemicrowave

• Large no. of satellites would take up Large no. of satellites would take up large section of spacelarge section of space

• Would require a network of satellitesWould require a network of satellites

• Proper agreement about SPS pathsProper agreement about SPS paths


ConclusionConclusion

• In order for SPS to become a reality In order for SPS to become a reality several things have to happen:several things have to happen:– Government supportGovernment support– Cheaper launch pricesCheaper launch prices– Involvement of the private sectorInvolvement of the private sector


Thank Thank youyou

Sattellite Power Station1

Business

Transcript of Sattellite Power Station1