Technical Review
Cox-ECE 4007
Andrew Cox
Section: RP1
Advisor: Dr. Kim
Group Name: RCVAC
Uses of Solar Panels in Low Power Application
Introduction
Clean energy is becoming an important issue in the technical world due to global
warming concerns. Solar panels convert solar energy to useful, renewable energy. There
are two main types of solar panels. The first type is a solar water heater system. This
type of system passes water through panels and uses the steam and hot water, created by
the solar energy, to get useful energy [1]. The second type of solar panels uses little
packets of energy from the sun, photons, to get useful energy. The solar panel is made up
of solar cells which are often referred to as photovoltaic cells [3]. When the photons hit
the depletion region of the transistors in the photo cells, dc currents is produced through a
process called generation [2]. The second type of solar panel is used more often for low
power applications, and is also the focus of this paper.
Commercial Applications for Solar Panels
Some of the first commercial applications of PV solar panels were small
calculators and satellites [3]. Common types of commercial applications for solar panels
are charging laptop computers, charging iPods, GPS systems, DC refrigerators, and other
electrical appliances. Portable solar panels are becoming more popular. The briefcase
solar panel power generator, for example, is a solar panel that is disguised as a briefcase
until the user is ready to use it for power generation [4]. There are also small solar panels
designed to use in cars. These types of solar panels are used to keep car batteries fully
charged which will result in a longer battery lifetime [5]. Solar panels are also put to use
in remote areas where running cable would be expense. A few examples of this are call
boxes along the interstate and street lights that run off batteries that charge during the
day. Some small solar panels even come with accessories for the convenience of the
consumer. Some of these accessories include different size battery charger adapters, long
cables, banana plugs, LED indicators, and Velcro strips for easy mounting [5].
1
Technical Review
Cox-ECE 4007
Underlying Technology and Implementation of Solar Panels
There are a few different specifications to consider when choosing solar panels
for different applications. The operating point voltage and current are the maximum
current and voltage levels at maximum power [2]. These operating points depend largely
on the size of the solar panel. A panel that is 1.510m long, .674m wide, and .05 m deep,
for example, might have an operating point voltage at 17.6V, an operating point current
at 7.1A, and a maximum power at 125W [6]. While a solar panel that is only .53m long,
.36m wide, and .017m deep might only have an operating point voltage at 17V, an
operating point current at 1.2A, and a maximum power at 20W [7]. The prices of solar
panels also increase with size. For example, a 110 Watt, 12V Solar panel might cost
$549.00, while an 85 Watt, 12V solar panel might cost $396.00 [5]. When implementing
solar power technology only hardware needs to be considered for most applications.
Most of the hardware that will be used with solar panels is different cables, connectors,
and mounting materials for the different type of applications.
2
Technical Review
[1]
Cox-ECE 4007
N. Roonprasang, P. Namprakai, N. Pratinthong. (2008, April). “Experimental
studies of a new solar water heater system using solar water pump”. Energy
[Online]. 33(4), 639-646. Available:http://www.sciencedirect.com.www.library.
gatech.edu:2048/science
[2]
R. Pierret, Semiconductor Device Fundamentals. Reading, Massachusetts:
Addison Wesley Longman, 1996, 356-361.
[3]
Energy Resources.(2008 Aug 31).”Solar Power-Energy From the
Sun,”[Organization Website]. Available:http://www.darvill.clara.net/
altenerg/solar.htm
[4]
Apex Distribution, LLC.(2006).”Briefcase Solar Panel Generator,”[Online
Website]. Available:http://apexdistribution.stores.yahoo.net/brsopapoge.html
[5]
Discount Solar.(2008). “Solar Panels,”[Online Website].Available:http://www.
Discountpv.com/solarpanels/index.htm
[6]
BP Solar.(2003 October).”25 Watt Photovoltaic Module”[Online data
sheet,BP3125].Available:http://www.oksolar.com/solar-panels/bp.htm
[7]
Discount Solar.(2008).”CD Technology CDT20 20 Watt Solar Panel with
Cable,”[Online specification sheet].Available:http://www.discountpv.com/solarpanels/cdt20.htm
3