Modeling Solar DHW in EnergyPro

Home Support Forum Lowrise Residential Code Questions Modeling Solar DHW in EnergyPro

This topic contains 2 replies, has 1 voice, and was last updated by  Pat Splitt 1 year ago.

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  • #5822


    EnergyPro includes a drop down menu in the solar section of the domestic water heating tab.  The manufacturer/product choices in the menu all appear to be of the “built up system” variety, meaning they consist of a separate collector(s) and storage tank with pumped circulation system between the two.  There seem to be no listings for integrated collector and storage (ICS) systems such as the SunEarth Copperheart or the TCT ProgressivTube products.  These units, as well as similar products, are certified under the SRCC OG-300 program with performance numbers that can be used to calculate annual Solar Savings Fractions.  They have also been around for many years and have stood the test of time.

    Is there a way to edit the listings in EP to include other legitimate OG-300 certified systems?  If not, what limits the listings to only those in the current dropdown menu?

    ICS solar DHW is a great way to insure compliance for many projects, particularly those pesky little garage conversion ADU’s.  I have seen projects go from a negative 20% compliance margin to a positive 15% (or more) margin with the addition of an ICS with only a 50% Solar Savings Fraction.  This solves a lot of problems.

    Stay Well & Think Good Thoughts,

    David Inger PE, LEED AP, CEM, Certified Gadfly

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  • #5824

    Pat Splitt

    The OG-100 calculation that seems to run in the current program is also defective.  If I model a simple 1 panel W/50 gal. tank system using the latest CEC F-Chart, I get an NSF of 0.72. The exact same system (with the same SRCC test file) on a house with the same floor area, modeled with the new compliance engine now amazingly has an NSF of 1.0! It has become 100% efficient! Now, if I re-run the program, but change the tank to 80 gal. the NSF is still 1.0. But, the compliance margin has gotten better. So, apparently, this system efficiency is now greater than 100%! This is complete B.S.

    Pat Splitt



    As an oversight, the CEC failed to accommodate the ICS systems in the newest release.  It is on their list of things to fix.

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