1. JIET SCHOOL OF ENGINEERING &
TECHOLOGY FOR GIRLS, JODHPUR
Presented to: Presented by:
Prof. Anil Raghav Pratibha Maurya

2. Space Based solar
power plant

3. Table of Contents
 Abstract
 History
 introduction
 How it would different
 Requirement for space solar power
 Design
 Microwave power transmission
 Transmission antenna
 Laser power beaming
 Rectenna
 Advantage
 Disadvantage
 Conclusion
 References

4. ABSTRACT
 SBSP is a system for the collection of
solar power in space, to meet the
ever increasing demand for energy on
Earth.
 In SBSP huge solar panels are fitted in
the large satellite which collects the
entire solar energy present in orbit
and beams it down to Earth.
 The collecting satellite would convert
solar energy into electrical energy on
board, powering a microwave
transmitter or laser emitter, and focus
its beam toward a collector
(Rectenna) on the Earth's surface.

5. History
 NikolaTesla in late 1890s, Pioneers of induction
Techniques. His vision for “WorldWireless
System”.
 In 1940s ability to convert energy to microwave
was developed.
 In 1964William C.Brown demonstrated a
Rectenna.

6. Introduction
 Space based solar
power(SBSP) is the
concept of collecting
solar power in space
(using an “SPS”, that is,
a “solar-power satellite”
or a “satellite power
system”) for use on
Earth.
 It has been in research
since the early 1970s.

8. Basic Concept
 Part of the solar energy is lost on its way through the
atmosphere by the effects of reflection and absorption.
 Space based solar power systems convert sunlight to
microwaves or Laser beam outside the atmosphere,
avoiding these losses, and the downtime (and cosine
losses, for fixed flat-plate collectors) due to the earth’s
rotation.

9. How it would different
 SBSP would different from current method in that the
mean used to collect energy would reside on an orbiting
satellite instead of on Earth’s surface.
 Higher collection rate a longer collection period due to
the lack of a diffusing atmosphere and nighttime in
space.

10. Requirement for space solar
power
 Low-cost, environmentally-friendly launch
vehicles.
 Large scale in orbit construction and
operations:-To gather massive quantities of
energy, solar power satellites must be large,
far larger than the international space
station(ISS).
 Power transmission :-To transmit power from
satellites to the Earth’s surface with minimal
environmental impact.

11. Design
 Space-based solar power essentially Consists
of three elements:
 A means of collecting solar power in space,
for example via solar concentrators, solar
cells or a heat engine.
 A means of transmitting power to earth, for
example via microwave or laser.
 A means of receiving power on earth, for
example via a microwave antenna(rectenna).

12. Microwave power transmission
 Power transmission via radio waves can be made more
directional, allowing longer distance power beaming,
with shorter wavelengths of electromagnetic radiation,
typically in the micro wave range.
 A rectenna may be used to convert the microwave
energy back into electrical.
 NASA study of solar power satellites required a 1-km
diameter transmitting antenna, and a 10 km Diameter
receiving rectenna, for a microwave beam at 2.45GHz.
 Experiments in the tens of kilowatts have been
performed.
 Conversion efficiency under experimental conditions was
measured to be around 54% efficient.

15. TRANSMITTINGANTENNAE
Power transmission via radio waves can be made
more directional, allowing longer distance power
beaming, with shorter wavelengths of
electromagnetic radiation.
Retro directive beam control systems have been
the preferred method of achieving accurate beam
pointing.
Microwave power beaming can be more efficient
than lasers, and is less prone to atmospheric
attenuation caused by dust or water vapor

16. Laser power beaming
 Power can be transmitted by converting electricity into a
laser beam that is then pointer at a photovoltaic cell.
 Compared to other wireless method:
 Collimated monochromatic wave front propagation allows
narrows beam cross-section area for transmission over
large distances.
 Compact size:-Solid state lasers fit into small products.
 No radio-frequency interference to existing radio
communication such asWi-Fi and cell phones.
 Access control:- Only receivers hit by the laser receive
power.

18. Earth based receiver
 The Earth-based rectenna would likely
consist of many short dipole antennas
connected via diodes.
 Microwave broadcasts from the satellite
would be received in the dipoles with about
85% efficiency.
 Rectennas would likely be several kilometers
across.

19. Rectenna
Stands for rectifying
antenna
Consists of mesh of
dipoles and diodes
Converts microwave to
it’s DC equivalent
Usually multi-element
phased array

20. Advantages
Unlimited energy resource.
Energy delivered anywhere in the world.
Zero fuel cost.
Zero co2 emission.
Minimum long rang environmental impact.
Solar radiation can be more efficiently collected in
space.

21. Disadvantages
 Storage of electricity during off peak demand hours.
 The frequency of beamed radiation is planned to be at
2.45GHz and this frequency is used by communication
satellites also.
 The entire structure is massive.
 High initial cost and required much time for construction.
 Launch costs.
 Would required a network of hundreds of satellites.
 The size of the antennas and rectenas.
 Geosynchronous satellites would take up large sections of
space.

22. Conclusion
This technology is still in development but
with support it will become operation of reality
providing a new source of clean energy.
“Will be a boon as we are running out of fossil
fuels”.

23. References
http://www.nss.org/settement/ssp/
http://martianchronicles.wordpress.com/2010
/06/20/our-burning-need-for-energy/
http://en.wikipedia.org/wiki/space-based
http://spacesolarpoer.files.wordpress.com
http://www.authorstream.com/Presentation/
vageta-1539555-space-based-solar-power/
http://www.slideshare.net/asertseminar/spac
e-based-solar-power-31961792