Landis+Gyr Revenue Meters No Longer CAISO Approved

According to CAISO, Landis+Gyr meters are no longer approved for new or replacement installations at CAISO-metered entities.

The change was communicated to Trimark from CAISO EDAS and was reflected in CAISO’s list of Active Authorized Revenue Meters, published September 29, 2023.

Landis+Gyr meters were a common choice for grid-connected resources starting in the 1990’s. Now, these meters are at the end of their expected service life. “As meters age, their accuracy drifts,” cautioned Casey James, Trimark Metering Manager. “That’s particularly true of 20-year-old meters. To support accurate metering and settlement data, Trimark recommends that resource owners replace these aging meters.”

Because supply chain issues remain problematic and demand is high, many CAISO-approved meters are on back order. Additionally, replacing and certifying a meter requires filing for a CAISO exemption, navigating the New Resource Implementation (NRI) process for meter replacement, and scheduling tests with CAISO.

“The process takes time,” advised James. “Being proactive with your meter replacement helps you avoid the surprise distraction of a meter failure and the accompanying frustration and uncertainty.”

While CAISO does not require resources to replace existing, certified Landis+Gyr meters, Trimark recommends that resources initiate the replacement process now.

Contact Trimark to get started.

About Trimark

Trimark Associates, Inc., the industry leader in complex metering and intelligent energy control, delivers industry-leading solutions to allow real-time operational control, enable informed management of power production operations, ensure regulatory compliance, and maximize revenue. Trimark’s turnkey products, engineering, and customer support services control, measure, and manage all aspects of power production that utility-scale power producers require to maintain peak business performance and achieve financial goals.

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