It is assumed that your class members have covered the preceding unit titled "Introduction to Photovoltaic Systems" prior to this lesson. It is easily located via the Lesson Planet website or an internet search. The highlight of this installment is building series and parallel circuits containing two photovoltaic cells and measuring the resulting currency and voltage. Junior engineers construct simple photovoltaic cells out of copper strips. A reading assignment and energy cost analysis are also part of this complete mini-unit.