Carl Gose EDSE 3275 Microteach Lesson Plan (revised)
10th Grade Physical Science
Solar Cell Lesson Plan
SC11.2.4
Students investigate the relationships between science and technology and the
role of technological design in meeting human needs.

Goals: In this lesson, students are introduced to the basic physics and chemistry
behind the operation of a solar cell. They will learn how a single crystal silicon cell
accepts energy from light and turns it into electricity.

Objectives: Students will be able to answer basic questions about the process of
turning light energy into electrical energy.

Misconceptions: Solar cells are often thought to produce energy from the collection
of heat from the sun. Heat does not play a significant role in solar electricity
production. It’s the light reaction that is crucial.

Student background: It is assumed that students are familiar with the electronproton-neutron model of the atom and with the basic ideas of bond formation
involving shared pairs of electrons. It is also assumed that they know about the idea
of valence electrons. The notion that like charges repel and opposites attract is also
assumed.

Material: small single crystalline photovoltaic cells wired to voltmeters, multimeters, batteries, light sources, automotive LED bulbs.

Methodology: Present the material in the handout “units of electricity”. Discuss how
solar cells turn sunlight into electricity.

Activity: Provide stations that include a photo cell attached to an analog voltmeter
and a multi-meter. Vary the stations by supplying different ones with an LED
automotive bulb, an intense light source and a small DC electric motor. After the
initial discussion demonstrate how to power the LED bulb and test for current with
the multi-meter. Also demonstrate how to measure voltage and resistance.

History: Solar cells are materials that turn sunlight into electricity. This effect was
first recorded by E. Becquerel, in 1839. The first solid state device was recorded to
show such an effect in 1877. However, it was in 1954 at Bell Labs when the solar
Carl Gose EDSE 3275 Microteach Lesson Plan (revised)
electric effect was demonstrated in silicon that the idea of producing useable
amounts of electricity from solar cells began.
The question is how do solar cells produce electricity?
Two facts are important to the understanding of how solar cells work.
· First, sunlight is composed of photons of various energies.
· Second, photons can interact with atoms, and if a photon has sufficient energy, it can
break the bond between an electron and the atom.
The silica composition of a solar cell provides relatively week bonds for photons to interact
with. The trick to making solar cells produce electricity is the ability to “collect” the
electron once it has been separated from the atom. The lattice wiring covering the cells
allows for the electrons to gather, the resulting flow of electrons is called the photocurrent.
The photocurrent is proportional to the number of photons hitting the solar cell.
Carl Gose EDSE 3275 Microteach Lesson Plan (revised)
Physical Science 10th Grade
Basic Electricity
Volt
The volt (symbol: V) is the SI derived unit for electric potential, electric potential difference, and
electromotive force.[1] The volt is named in honor of the Italian physicist Alessandro Volta
(1745–1827), who invented the voltaic pile, possibly the first chemical battery.
Volts=Amps x Ohms, V=Watts/Amps
Amp
The ampere (symbol: A) is the SI unit of electric current[1] (symbol: I) and is one of the seven[2] SI base
units. It is named after André-Marie Ampère (1775–1836), French mathematician and physicist,
considered the father of electrodynamics. In practice, its name is often shortened to amp.
In practical terms, the ampere is a measure of the amount of electric charge passing a point in an
electric circuit per unit time with 6.241 × 1018 electrons, or one coulomb per second constituting one
ampere.
Ohm
The ohm is defined as a resistance between two points of a conductor when a constant
potential difference of 1 volt, applied to these points, produces in the conductor a current of 1
ampere, the conductor not being the seat of any electromotive force.
Ohm=V/A
Watt
The watt (pronounced /ˈwɒt/ wot; symbol: W) is a derived unit of power in the International
System of Units (SI), named after the Scottish engineer James Watt (1736–1819). The unit,
defined as one joule per second, measures the rate of energy conversion.
Watts=Volts x Amps
Carl Gose EDSE 3275 Microteach Lesson Plan (revised)