STANDATA Variance on Energy Storage Systems in Residential Buildings

November 1, 2023

Industry has identified concerns regarding Energy Storage System (ESS) requirements. This variance permits the installation of an ESS at a dwelling unit or residential occupancy not exceeding 20 kWh for any single ESS, as an alternative method to the C22.1:21 – Canadian Electrical Code, Part I.

The current electrical code, C22.1:21 – Canadian Electrical Code, Part I, Rule 64-918 2) prohibits the installation of ESS’s utilizing batteries below grade, including basements of dwelling units. Additionally, 64-918 4) prohibits ESS’s with a storage capacity above 1 kWh from being installed in a dwelling unit or living space of a residential occupancy including clothes closets, storage rooms, bathrooms, stairways, or in any similar undesirable locations.

The next electrical code is C22.1:24 – Canadian Electrical Code, Part I is expected to contain requirements for ESS installations up to 20 kWh for any single ESS installed at a dwelling unit or residential occupancy.

The upcoming code provisions in the 2024 edition were developed by the CSA Group. Additional standards related to ESS’s include:

  • Batteries for Use in Stationary and Motive Auxiliary Power Applications ANSI/CAN/UL1973, which covers battery safety,
  • Energy Storage Systems and Equipment ANSI/CAN/UL 9540, which covers overall ESS system safety,
  • ANSI/CAN/UL 9540A Standard for Test Method for Evaluating Thermal Runaway Fire Propagation in Battery Energy Storage Systems, which covers fire propagation testing.

Go HERE for more information.

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