[RE-wrenches] ESS and Calculated Load in Texas

[Chris Sparadeo]

Hi all,

I’m finding out that some jurisdictions in Texas are requiring ESS output
to be equal to or greater than the calculated load of a dwelling. For
example, if backing up the whole home, and the service load is calculated
at 150A, the ESS would require to continuously output 150A OR EMS is
required to bring the calculated load to or below that of the ESS. AHJ’s in
a few areas of Texas are dying on this hill and to actually meet the
calculated load, systems would need to be significantly larger than needed.

I know that previous versions of 706 (specifically NEC 2017) could lead one
to argue this point, but Texas had adopted NEC 2023, and it’s only article
710 that indicates a system operating in isolation of the grid should has
sufficient output to supply load to the largest backed up load.

Has anyone run into this issue? And if so, what have people been doing to
either meet these outdated requirements or successfully push back?

Thanks!


Chris Sparadeo

VT Master Electrician # EM 08220
C_802-369-4458
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