# Using Lab Measurements to Determine the Feasibility of a Photovoltaic Panel

**This activity was selected for the On the Cutting Edge Reviewed Teaching Collection**

This activity has received positive reviews in a peer review process involving five review categories. The five categories included in the process are

- Scientific Accuracy
- Alignment of Learning Goals, Activities, and Assessments
- Pedagogic Effectiveness
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This page first made public: Jun 14, 2012

#### Summary

This activity is based on the use of a solar module. It can be performed in a lab setting of as a lecture demonstration activity. Using a solar module that we have on hand (18 volts – no load) we determine a practical value of power output. We aim the panel directly at the sun and then take the following measurements using a digital multi meter: (1) no load voltage, (2) loaded voltage, and (3) resistance value of the load resistor. Using these data, and a standard estimation of solar isolation, the students are instructed to compute the output power of the module as well as the efficiency of the module.

## Learning Goals

(1) the understanding of the meaning of the term insolation,The students are engaged in data collection and data analysis. Additionally they will be engaged in the synthesis of a concept about the feasibility of exclusively using photovoltaic systems for the production of electricity. The formulation of such a concept relates to sustainability because it helps the students to understand that no single energy source will be sufficient.

(2) an understanding of internal resistance as it relates to a source voltage,

(3) the ability to compute the output power from a solar cell/module/array,

(4) the ability to compute the cost of producing electricity using a photovoltaic system.

## Context for Use

## Description and Teaching Materials

In class the students are presented with a blank data table and are instructed to "fill out" the table with the appropriate measurements, including the resistance of the load, the no load voltage and the loaded voltage. The students are asked to compute: (1) the load current, and (2) the output power. Furthermore the students are asked to compute the following: (3) the efficiency of the module based on an ideal output rating of 1KW/M2, (4) the output power in KWhr for a day/month/year based on an average day of 5 hours of sunlight. Lastly the students are asked to determine (5) how many solar modules would be needed to provide electricity for a 1,000 square foot home, (6) the cost/KWhr of electricity generated by the solar module.

Solar Panel Drawing (Microsoft Word 2007 (.docx) 56kB Jun14 12)