New Solar Homes PARTNERSHIP

CECPV Calculator Version 2.3
Updated: June 4, 2008

This is a detailed hourly calculation tool based on the 5-parameter model developed by the Solar Energy Laboratory at the University of Wisconsin. The CECPV Calculator incorporates detailed inverter performance modeling and uses weather data from the 16 climate zones in California (as used by the Title 24 compliance calculations).

The MS Excel interface to the calculation engine is provided by the Energy Commission for download and allows the user to select PV modules and inverters from a library of eligible equipment. Please check this website periodically for updates as new equipment may be added to the NSHP eligibility lists. The CECPV Calculator generates the estimated monthly kWh production and annual TDV (kWh) production for the specified system. It also determines the appropriate incentive amount as calculated by the Expected Performance Based Incentive approach outlined in the NSHP Guidebook.

Note: To qualify for an incentive, residential buildings must receive electricity distribution service at the site of installation from one of four investor-owned utilities (IOUs) in California. The IOUs are: Pacific Gas & Electric Company, Southern California Edison Company, San Diego Gas & Electric Company, and Southern California Water Company - doing business as Bear Valley Electric Service. On the list within the calculator, there are cities that are not served by the above utilities. You can determine what utility serves your project by going to the page called Finding Your Utility Company.

NSHP applications must use a version of the NSHP CECPV Calculator that is listed as "certified" on the date the NSHP application is postmarked (or date of submission for electronic NSHP applications).

Calculator Support

• How to Find the EMF File step-by-step guide
  (PowerPoint Show, 417 kilobytes)

• PV Calculator Tutorial step-by-step guide for using the NSHP PV Calculator.
  (Acrobat file, 1.6 megabytes)

Software requirements

• PC platform with MS Windows OS (Windows 2000, XP, Vista)
  (Sorry a Macintosh version is not available, nor is it anticipated.)
• Microsoft Excel (2000, 2002, 2003, 2007)

Installation Instructions

1. For automated installation, left-click and install the CECPV2_x.msi file. The program will be placed in the C:\CECPV2x directory. A shortcut icon named "v2.x NSHP CECPV Calculator" will be placed on the desktop.



2. 2. If you desire the program to be installed in a different directory, download the CECPV2_x.zip file. Extract the contents of the zip file into a new folder on your hard disk.



3. When available above, download and install the most recent Module/Inverter Update to the same directory where the calculator is installed.

Operating Instructions

1. Using the CECPV Calculator desktop icon (automatic installation option), open the Excel spreadsheet titled CECPV2_x.xls. If you used the manual installation option, you will need to locate and open the CECPV2_ x.xls file from your hard disk. Be sure to enable Macros when asked in the opening window. Also set your Macro Security (menu Tools>Macro>Security) level to medium or lower to allow the program to run (depending on your Excel options).

2. The program starts on the "Site Info" tab. The information requested is for populating the compliance forms. You may skip the generation of the compliance forms by checking the "Run Test Simulation Only" box. Skipping the compliance forms will reduce the running time of the program. Note that the compliance forms must be supplied when making a NSHP application.

3. Use the "Continue" button to move to the "CA Flexible Installation" tab and complete the required inputs. Use the "Run" button to initiate the simulation.

4. For systems requiring additional installation parameters, use the "Specify Additional Parameters" button to move to the "Detailed Input" tab and complete the required inputs.

5. For minimal shading, use the "Minimal Shading" button and then the "Run" button to initiate the simulation.

6. To input shading obstruction information, use the "Add Shading Detail" button, with the "Minimal Shading" box unchecked. This moves you to the "Shading Input" tab where you can complete the required shading obstruction inputs. When shading obstructions are being applied, use the "Run" button from the "Shading Input" tab.

7. The CECPV tool will run in the background and show up as a minimized program. Please DO NOT close the CECPV window or quit the program. The screen may go blank or all white while the simulation is running. The simulation without compliance forms can take up to 1 minute to complete. The simulation with compliance forms can take up to 3 minutes to complete.

8. At the end of the simulation the "Results" tab is shown with the monthly and annual kWh production values, the annual TDV and the estimate of the incentive ($).

9. If the simulation was run with compliance forms, the "View Compliance Form" button will take you to the CF-1R-PV form which can then be printed for submission with your NSHP application.

10. The "Run Another Simulation" button will take the user back to the "Site Info" tab.

11. For questions and instructions to run the main engine for PV calculations outside of the Excel interface please email SGupta@energy.state.ca.us or PSaxton@energy.state.ca.us.

Additional information

1. Manufacturers interested in adding their equipment to the NSHP eligible equipment list should contact Energy Commission contractor Pete Baumstark, KEMA, Inc., at pete.baumstark@us.kema.com.



2. The detailed hourly output from the tool is saved in the CECPV_output.csv file found in the C:\CECPV2x directory. Rename this file to save the results from a run, since it will get overwritten every time a new run is initiated. Similarly the field verification table output can be found in the FVT.csv file which is also overwritten with every run.



3. Details of the algorithm used in the calculator can be found in two documents placed in the program folder, PV_5_PARA_MODEL.pdf and CEC_PV-calculator_description.pdf.