AE 868
Commercial Solar Electric Systems



Lesson 2 Scenario

Imagine this: you work for the procurement team for a solar company and your director asks you to attend one of the biggest international solar trade shows (i.e.. Solar Power International), where you are networking with PV manufacturer representatives to learn about new material and technology advancement. You come across a Solar Module booth, so you start talking about your team and what types of PV systems you offer to clients. The representative starts going over data-sheets and the series of PV modules they make.

What are the questions you can ask to narrow down your choices of PV modules? Is it PV technology type, efficiency, or the voltage and current of modules that is most important?

You continue walking and stop by other booths, where you get the same exact power rating information from the representatives. Now you have to select a few panels by comparing their specifications. Ignoring the cost of the modules, what factors dictate your decision to select the panel? Is it module efficiency, color, or dimensions?

You leave the trade show with more specification sheets from other PV manufacturers. The next day you need to prepare a report to your director, who needs more numbers to help evaluate each panel. Since it is not easy to test the actual modules’ performance, are there tools or software that you can use to learn more about the annual energy production of these PV modules?

It is obvious to us that PV modules should generate more energy when there is more sun. However, are there any other factors that affect the performance of these PV modules when they are installed? Can it be the orientation of modules or the ambient temperature? Are there any methods to optimize the performance of the PV system?

Since you are a company operating in the US, can any module be installed, or should it meet some kind of test standards and certifications?

In this lesson, we will discuss topics that lead to answers to all the questions in the scenario above. We will enlighten PV designers to look for the best modules that fit their application.

Learning Outcomes

At the successful completion of this lesson, students should be able to:

  • Identify PV terminology and key electrical characteristics of PV modules at various operating conditions.
  • Interpret a PV module manufacturer's data specification sheet and key parameters for various test standards.
  • Discuss factors affecting performance of PV devices and the impact of changing irradiance and temperature.
  • Apply strategies to optimize production of PV systems using industrial tools such as Solar Advisor Model (SAM) and PVwatt software to simulate PV output.
  • Identify shading effects on PV array and series and parallel connection of modules.

What is due for Lesson 2?

Lesson 2 will take us one week to complete. Please refer to the Calendar in Canvas for specific timeframes and due dates. Specific directions for the assignments below can be found within this lesson and/or in Canvas.

Complete the following Lesson Assignments:

  • Read through the Lesson Content
  • Complete the Required Reading Assignments:
    • Chapter 5, Photovoltaic Systems by James P. Dunlop (text)
  • Look over the Recommended Readings:
  • Complete the Lesson 2 Activity
  • Begin working on your Procurement Report
  • Take the Lesson 2 Quiz in Canvas

*Students who register for this Penn State course gain access to assignments, all readings, and instructor feedback, and earn academic credit. Information about registering for this Penn State course is available through the Renewable Energy and Sustainability Systems Online Masters and Graduate Certificate Programs Office.


If you have lesson specific questions, please feel free to post to the Lesson 2 Questions discussion forum in Canvas. While you are there, feel free to post your own responses if you, too, are able to help a classmate with a question. If you have questions about the overall course or wish to share and discuss any "extra" course related commentary (interesting articles, etc.), please feel free to post to the General Questions and Discussion forum.