AE 868
Commercial Solar Electric Systems

Simulation Exercise


In Lesson 2 we will use simulation software. This exercise requires you to download NREL's System Advisor Model (SAM) and the NREL PVWatt tool for use in the next lesson. This Exercise is ungraded, but it is essential for you to become familiar with these tools to better follow along with the class topics and Lesson Activities.

Simulations Exercise
Activity Details

Part I: Download SAM

  1. Create a User Account and choose Photovoltaic as the Technology Focus at the bottom of the page.
  2. Follow the Download Installation Instructions
    (Note: The current version of System Advisor Model is SAM (latest version available on the website). It requires about 800 MB of disk space, and either Windows 8/7/Vista or OS X 10.8 Intel or later. SAM is a 32-bit program that will run on both 32-bit and 64-bit operating systems. If you do not have one of these operating systems, you can browse their list of Legacy Versions as an alternative.)
  3. Install and launch SAM on your computer. Try to "start a new project" with Photovoltaic (detailed) and "Residential" scenario. The defaults are pretty reasonable in SAM. If you've never tried something like SAM, don't worry. This is really just an exploration step, and you can't really break anything by opening a new project and running it. So just explore a little and have some fun.
  4. If you successfully create a new project (I'll name an example "Simpsons_Solar_Springfield"), hit the big green arrow button on the lower left. The program will run a year's solar data and will output a heap of results. The output in the lower left field are the summary stats for the project, usually estimating 25 years of a solar project.

Part II: PVWatt

To access PVWatt, you have two options:
  1. To access PVWatt on any machine without downloading any software, go to the NREL PVWatt website. (Note: the online version has limited options when dealing with the results data.)
  2. To access the detailed version of the PVWatt software, after you download SAM and when selecting new project, you can choose PVWatt option.

Part III: Try Out SAM and PVWatt in a Simulation Exercise

Imagine you have a client located in State College, PA. The client wants to install 10 kW using PV technology. You have to come up with the estimated annual, monthly, and daily energy production.

  • SAM: After you download the latest version of SAM and choose Photovoltaic (detailed) then select Residential, choose “Trina solar TSM-250PA05” for PV modules and use Enphase Energy M 215 (if SAM asks for inverter selection) system configuration (series/parallel) and simulate at 35° title angle and 180° azimuth at that location.

  • PVWatt: After you access NREl PVwatt, try to choose the same values of the system size, tilt, and azimuth angles for the same location and simulate the energy production and compare with SAM. (Note: choose "Standard" for Module type options and "Fixed" for Array type. You may leave all other default values as is).

Deliverable: Gather your Result Tables

Take a screenshot (including the table) of the SAM result and the PVWatt result. Copy the screenshots into a Word document. 
Please use the following naming convention: Last Name_First Name L1 Simulation Exercise.docx. 
Follow the directions below for submission.

Submission Instructions
  1. Go to the appropriate Lesson in Canvas.
  2. Select the Simulation Exercise link.
  3. Click the Submit Assignment button.
  4. To upload a file from your computer, click the Choose File button. When the file window appears, locate and click the name of the file. At the bottom of the window, click the Choose or Browse button (depending on your browser).
  5. Click the Submit Assignment button.