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DOE OSTI · 3377787

Updating PV and Battery Bill Savings Calculations for Net Billing: New Best Practices for Input Data and Uncertainty

Mirletz, Brian [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000309456007)·Speetles, Brittany [National Laboratory of the Rockies, Golden, CO (United States)]·Keith, Janine [National Laboratory of the Rockies, Golden, CO (United States)]
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Abstract

Jurisdictions are increasingly adopting compensation structures for distributed PV and PV-battery systems that price exported energy lower than energy consumed onsite (net billing rates). Standard methods for calculating the bill savings from PV and PV-battery systems were developed for net metering structures, and applying these same methods to net billing structures (such as using Typical Meteorological Year weather with actual year load) introduces bias errors that underestimate PV-battery system bill savings by between 1.5\% and 9\%, depending on the utility rate. We assess the magnitude of these errors and compare them to other sources of uncertainty when estimating the bill savings from PV and PV-battery systems under more complex utility rates.

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14 SOLAR ENERGY29 ENERGY PLANNING, POLICY, AND ECONOMY97 MATHEMATICS AND COMPUTINGbatteriesbehind-the-meternet billingPV-batterySAMsolar plus storageSystem Advisor Modeltechno-economic analysis

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Mirletz, Brian [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000309456007), Speetles, Brittany [National Laboratory of the Rockies, Golden, CO (United States)], Keith, Janine [National Laboratory of the Rockies, Golden, CO (United States)]. 2026-06-24. Updating PV and Battery Bill Savings Calculations for Net Billing: New Best Practices for Input Data and Uncertainty. https://doi.org/10.66816/pr4938357

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