Southwest Power Pool Anticipates Adequate Supplies to Meet Winter Energy Needs

The Southwest Power Pool (SPP), which manages the power grid across the central U.S., anticipates a 98.5 percent probability that the region will have sufficient power generation capacity to meet projected peak demand and maintain energy reserves this winter season, according to a Nov. 19 press release.

This prediction is based on its annual winter assessment which looks at factors such as past and future energy demand trends, weather forecasts, variability of wind energy output, drought conditions, and power transmission outages to evaluate energy reliability during the winter months from December to March.  Based on the upcoming winter weather forecasts, peak demand trends, and available generation capacity, SPP expects a larger power generation surplus margin compared to the last two seasons.

In the 2024-2025 Winter Readiness Assessment by the North American Electric Reliability Corporation, the SPP area has an anticipated reserve margin of 44 percent, which is five percentage points higher than the previous winter. The 2024-2025 winter risk period scenario analyzes a peak demand of 46 gigawatts (GW) with anticipated resources totaling 66.1 GW.

The SPP transmission region covers an area of 546,000 square miles in southern and central parts of the U.S. across 14 states, including Montana, Texas, Minnesota, and Louisiana. With around 61,000 miles of transmission lines and 756 generating plants, the organization serves over 18 million residents. The region experienced extreme winter weather during Winter Storm Uri in 2021 and Winter Storm Elliott in 2022, leading to regulators taking action to enhance grid reliability and mitigate power disruptions during extreme weather.

Earlier this year, the SPP board took several steps to boost electric reliability in the future event of extreme weather and peak demand. In August, the board approved increasing the minimum planning reserve margins for utilities to 36 percent during the winter season to improve grid reliability. The new planning reserve margins will take effect in 2026.

A few weeks ago, the board also approved one of the largest transmission plans in its 20-year history, a $7.7 billion plan to finance 89 transmission upgrades in the region. The projects will focus on building 2,333 miles of new transmission lines and rebuilding 495 miles of existing ones. This investment will significantly reinforce the electric grid, improving resilience in the face of extreme weather.