Solar Water Heating Calculation Using SRCC Certified Solar Water Heating System ratings (OG-300)
This Solar Fraction Calculator for Rated Systems (OG 300) calculation sheet is a Microsoft Excel spreadsheet used for determining the credit for certified solar water heating systems towards complying with the Building Energy Efficiency Standards, meeting the energy efficiency requirements of the New Solar Homes Partnership, or other incentives programs that require specific percent savings beyond the standards. The calculation uses the SRCC OG300 Solar Energy Factor to determine the Solar Fraction to be input into a Commission-approved building energy compliance computer program. The solar energy factor is defined as the actual solar energy collected by the system divided by the electrical or gas energy supplied to the system.
To use the certified Solar Fraction Calculator for Rated Systems (OG-300) calculation spreadsheet, the following information is required. Obtain this information from the building plan set for your project, and from the SRCC data sheet for the system that will be used. Refer to the example spreadsheet for additional guidance in filling out the required information.
- Project Title: Enter the name of the project.
- Project Address: Enter the address of the project.
- Floor area of the home: in square feet: This information can be found on the construction plan set. (This approach can be used only for a solar water heating system serving a single family home or an individual dwelling unit in a multi-family building).
- Climate zone number: Enter the California climate zone corresponding to the geographical location of the building. This can be determined by clicking on the following link California Climate Zone Maps.
- Solar Energy Factor (SEF): Find the solar water heating system you are using in the OG-300 Directory of Certified Solar Water Heating System Ratings. Refer to the solar system design specifications to determine the Solar Energy Factor (SEF) in the Directory. Print a data sheet for your system to include in the documentation package. Click on the following link to download: SRCC OG-300 Directory.
- Energy Factor for Water Heater: Enter the energy factor of the water heater used to rate the OG-300 Water Heating System. This will be either 0.6 for a gas, or 0.9 for an electric water heater.
Run the Solar Fraction Calculator for Rated Systems
Click on the link below to download the Microsoft Excel spreadsheet and save the file on your computer. The spreadsheet is formatted as a compliance form, CF-SR-300. Open the file to activate the spreadsheet.
After the required information is entered, the calculated Solar Fraction will be reported at the bottom of the spreadsheet. Print the completed spreadsheet (CF-SR-300) for submittal with the SRCC data sheet and the CF-1R.
The Solar Fraction determined by the spreadsheet is entered as an input to a Commission-approved building energy compliance computer program to determine the contribution of the solar water heating system towards compliance with Building Energy Efficiency Standards, meeting the New Solar Homes Partnership energy efficiency requirement, or qualifying for other incentive programs.
If this does not work or you have questions about the program contact the Energy Hotline at (916) 654-5106, toll free at (800) 772-3300 or send an e-mail to firstname.lastname@example.org. Please do not contact the Webmaster for assistance.
Download Solar Fraction Calculator for Rated Systems
Right-click the link to download and save the file (PDF file, 2 pages, 70 kb).