In the United States, electricity demand, or load, has begun to grow following several stagnant decades. This trend appears first in utility forecasts, the backbone of the utility investment plans that inform billions of dollars of infrastructure investments. The scale of projected load growth and its potential risks require regulators to ensure that load forecasts remain useful in guiding consequential decisions.

This report is a resource for regulators who wish to understand the current landscape of large load forecasting and explore options for how to evolve forecasting practices as large loads emerge in their jurisdictions.

Specifically, this report includes:

• Deep dives into different large load drivers and their unique characteristics that affect the grid.
• Concise best practices for load forecasting and case studies explaining how three utilities are forecasting large loads today.
• Actions that regulators can take to improve load forecasts that are limited, outdated, and opaque today, shown in the table below.
• Discovery-ready questions that regulators can leverage to ensure utilities are using robust large load forecasting practices.

This report was informed by the second cohort of Reg Lab, Near Term Responses to Load Growth. It includes insights from hours of discussions between staff, best practices shared by subject matter experts, and examples of actions that commissions have already taken to improve forecasting. We hope these insights and examples empower commission staff across the nation to navigate possibly the first period of load growth during their careers, but likely not their last.

Please contact Jeffrey Sward (jsward@rmi.org) for further support on load forecasting and Katerina Stephan (kstephan@rmi.org) with questions about Reg Lab.