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Disclaimer — This paper partially fulfills a writing requirement for first year (freshman) engineering students at the University
of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is based on
publicly available information and may not be provide complete analyses of all relevant data. If this paper is used for any
purpose other than these authors’ partial fulfillment of a writing requirement for first year (freshman) engineering students at
the University of Pittsburgh Swanson School of Engineering, the user does so at his or her own risk.
THE USE OF MICROWAVE WIRELESS POWER IN SOLAR POWER
SATELLITE SYSTEMS
Nicholas Haver, ngh9@pitt.edu, Bursic 2:00, Alex Rugh, arr95@pitt.edu, Mahboobin 4:00
Revised Proposal — The popularity of solar power as a form
of clean, sustainable energy has seen substantial growth since
the beginning of the 21st century. Despite its growing
popularity, solar energy accounted for only 0.5 percent of
global electricity demand in 2011 [1]. Currently, further
development and implementation of solar power systems has
been limited due to its intermittency and a lack of
infrastructure. Solar power production is often inconsistent
because factors such as clouds and other weather conditions
can affect how much solar energy the solar cells can harness.
Additionally, because solar panels are often installed in large
arrays, many “solar farms” are in remote locations.
Therefore, additional funds are required to transmit the
energy produced back to civilized areas where it can be
distributed through existing power grids.
Because of these setbacks, recent research has been dedicated
to the design and implementation of solar power satellite
systems. Solar power satellite (SPS) systems are comprised of
a satellite in geosynchronous orbit containing an array of
solar cells, an electromagnetic transmitter on the satellite and
an electromagnetic receiver on earth [2]. This paper will
focus on microwaves – the most common type of
electromagnetic transmission – in SPS systems, and how they
are used in wireless power transmission.
These solar power satellites produce energy in the form of DC
(direct current) power. This power is sent to a microwave
oscillator where it is converted into radio frequency power,
usually in the form of microwaves [3]. Other methods of
generating microwaves include magnetron, klystron, and
TWT vacuum tubes and semiconductor amplifiers, all of
which have been considered due to their high power
conversion efficiency and low cost [4]. These microwaves are
then ejected through a phased array antenna that distributes
the electromagnetic power across the aperture. The antenna
is computer controlled to monitor and control the strength of
the power beam being directed towards Earth [5]. Special
receiver rectennas situated on Earth receive the microwaves
and convert them into direct current (DC) electricity.
The implementation of solar power satellite systems presents
possibly negative ecological and civilian health impacts due
to the constant delivery of microwaves to various places on
Earth. The public’s reassurance that there is no danger of
adverse effects of radiation is crucial to their acceptance and
University of Pittsburgh Swanson School of Engineering 1
1/29/2016
thus the success of the SPS project [6]. Therefore, the effects
on humans and ecological surroundings that occur at the
system’s operating frequency of 2450 MHz CW must be
investigated thoroughly [6].
REFERENCES
[1] S. Lewis and D. Nocera. (2012). “Solar Power
Background.” Center for Climate and Energy Solutions.
(online article).
http://www.c2es.org/technology/factsheet/solar
[2] G.A. Landis. (2006). “Re-Evaluating Satellite Solar Power
Systems for Earth.” NASA John Glenn Research Center.
(online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4
060043&isnumber=4059868
[3] T. Li, L. Wu and Z. Chen. (2015). “Research Overview on
Wireless Power Transmission Technology.” Institute of
Crustal Dynamics. (online article).
http://www.matecconferences.org/articles/matecconf/pdf/2015/03/matecconf_i
ceta2015_02021.pdf
[4] S. Sasaki and K. Tanaka. (2011). “Wireless Power
Transmission Technologies for Solar Power Satellite.”
Institute of Space and Astronautical Science. (online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5
877137&isnumber=5876647
[5] J. McSpadden and J. Mankins. (2002). “Space Solar
Power Programs and Microwave Wireless Power
Transmission Technology.” Boeing Phantom Works. (online
article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1
145675&isnumber=25789
[6] D. Cahill. (1979). “An Overview of Satellite Power
Systems-Microwave Health and Ecology Program.” United
States Environmental Protection Agency. (online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1
123962&isnumber=24839
Nicholas Haver
Alex Rugh
existing technology for SPS use and the advantages
microwave power transmission has over analog power grids.
Information from this article will be used to discuss how
microwave transmission works and the changes needed for
use on a global scale.
ANNOTATED BIBLIOGRAPHY
D. Cahill. (1979). “An Overview of Satellite Power SystemsMicrowave Health and Ecology Program.” United States
Environmental Protection Agency. (online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1
123962&isnumber=24839
This paper, from the Experimental Biology Division of the
Health Effects Research Laboratory, informs about the
possibilities of negative effects on humans and surroundings
of microwave radiation at certain frequencies. The paper
explains how, in the event that these negative effects exist, the
reaction of the public could be detrimental to the space solar
power system concept. This paper will help us identify the
risks associated with the concept’s survival rather than the
health of the public.
X. Li, J. Zhou, B. Duan, Y. Yang, Y. Zhang and J. Fan.
(2015). “Performance of Planar Arrays for Microwave Power
Transmission with Position Errors.” IEEE Antennas and
Wireless Propagation Letters. (online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7
088559
This article, from the IEEExplore Digital Library, goes
over the effects of position errors in antennas on beam
collection efficiency in microwave power transmission using
planar arrays. The article uses mathematical formulation to
represent the relationship between position errors and beam
collection efficiency, and also describes and discusses
experiments on the matter and the results. This article will
help us in understanding the factors which affect microwave
power transfer and the mathematics behind those factors.
G.A. Landis. (2006). “Re-Evaluating Satellite Solar Power
Systems for Earth.” NASA John Glenn Research Center.
(online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4
060043&isnumber=4059868
This article, published by NASA, examines several new
concepts in solar power satellite systems in an effort to make
the system more economical. The article expands on satellite
construction, rectenna array design and the technical, political
and economic barriers the concept must overcome before
widespread use is considered. This article will be used to
discuss recent advancements in SPS technology and what role
microwave transmission plays in this technology.
J. McSpadden and J. Mankins. (2002). “Space Solar Power
Programs and Microwave Wireless Power Transmission
Technology.” Boeing Phantom Works. (online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1
145675&isnumber=25789
This article, from a professional journal specializing in
microwave transmission, presents a summary of a NASA SPS
research project and outlines the state of microwave wireless
power transmission development. The article discusses
several options for microwave generation and factors such as
output power, efficiency and operational life expectancy of
these options. The article will be used to evaluate several
methods of microwave generation and the pros and cons of
each.
S. Lewis and D. Nocera. (2012). “Solar Power Background.”
Center for Climate and Energy Solutions. (online article).
http://www.c2es.org/technology/factsheet/solar
This article, published by a non-government global energy
organization focused on sustainable energy solutions, outlines
recent United States solar power consumption in comparison
to other energy sources. The article explains recent
advancements in solar power technology and the challenges
this technology faces going forward. Information from this
article will be used as a baseline for current solar energy
utilization and to demonstrate the need for technological
advancement in the area.
J. Osepchuk. (2002). “How Safe Are Microwaves and Solar
Power from Space?” Full Spectrum Consulting. (online
article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1
145676
This article, from the IEEExplore Digital Library, goes
over the public concerns of solar power satellites and how
dangerous microwaves are to the public and to the
environment. The article explains how past technologies have
been restrained by public disagreement and addresses various
concerns related to the health of the public and the
environment. This article will help us identify specific
concerns of the technology and help us decide whether or not
these concerns are legitimate.
T. Li, L. Wu and Z. Chen. (2015). “Research Overview on
Wireless Power Transmission Technology.” Institute of
Crustal Dynamics. (online article).
http://www.matecconferences.org/articles/matecconf/pdf/2015/03/matecconf_i
ceta2015_02021.pdf
This article, from a professional journal specializing in
materials science, engineering and chemistry, discusses
modern breakthroughs in wireless power transmission. It
details terrestrial wireless power applications, how to scale
S. Sasaki and K. Tanaka. (2011). “Wireless Power
Transmission Technologies for Solar Power Satellite.”
Institute of Space and Astronautical Science. (online article).
2
Nicholas Haver
Alex Rugh
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=5
877137&isnumber=5876647
Published by the Japan Aerospace Exploration Agency
(JAXA), this article discusses research related to highefficiency power conversion and high-accuracy beam
projection that must be conducted before microwave
transmission can be used in SPS applications. The article also
discusses possible wireless power transmission options other
than microwaves. This article will be used to discuss the
ongoing testing and research regarding microwave
transmission that must be completed before its use in SPS.
D. Sato, N. Yamada and K. Tanaka. (2015). “Thermal
Characterization of Hybrid Photovoltaic Module for the
Conversion of Sunlight into Microwave in Solar Power
Satellite.” Nagaoka University of Technology. (online article).
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7
355860
This paper, from the Department of Mechanical
Engineering at the Nagaoka University of Technology,
describes the design of a hybrid photovoltaic module used for
the conversion of solar energy into microwaves. The paper
explains the design of the module and details various
simulations and experiments on how temperature affects the
performance of the module. This paper will help us discover
and explain how the energy conversion works and the various
factors that affect it.
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