SUBMITTED BY:
SUBHASMITA DALABEHERA

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Satellite Power Station and Microwave Power Transmission
Introduction
The demand for energy worldwide has increased by 40% in the last two decades.
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.
Requirement of clean energy sources.
Basic Concept
Solar Power Satellites providing a better way of power generation
Transmission of power to earth via microwaves
Collection of power by specially developed antennas (rectennas)
SOLAR POWER SATELLITES
Solar Power Satellite or SPS, is a proposed satellite built in geostationary orbit that uses microwave power transmission to beam power to a very large antenna on Earth where it can be used in place of conventional power sources.
Basic components
A huge solar collector, typically made of solar cells.
D.C. to Microwave conversion through magnetron
Transmitting antenna sub array on the satellite, aimed at earth.
Reference system
Advantages over Earth based solar power
More intense sunlight
In geosynchronous orbit, 36,000 km (22,369 miles) an SPS would be illuminated over 99% of the time
No need for costly storage devices for when the sun is not in view
Waste heat is radiated back into space
Power can be beamed to the location where it is needed
No air or water pollution is created during generation
Microwave Power Transmission
How the power gets to Earth?
From the Satellite
Power from the satellite is sent to Earth using a microwave transmitter
Received at a “rectenna” located on Earth
Recent developments suggest that power could be sent to Earth using a laser
Microwaves
Frequency 2.45 GHz microwave beam
Power level is well below international safety standard
Rectenna
“An antenna comprising a mesh of dipoles and diodes for absorbing microwave energy from a transmitter and converting it by rectification into D.C. power.”
Microwaves are received with about 85% efficiency
95% of the beam will fall on the rectenna
Basic block diagram
Working model of Japanese Space Solar Power Plant SPS2000 in Sagamihara, Japan.
Environmental
Possible health hazards
Effects of long term exposure
Exposure is equal to the amount that people receive from cell phones and microwaves
Location
The size of construction for the rectennas is minimized
Conclusions
More reliable than ground based solar power
In order for SPS to become a reality several things have to happen:
Government support
Cheaper launch prices
Involvement of the private sector