The Weekly Fill-Up | September 8-12

September 8, 2025

This week, energy markets in South Dakota and across the U.S. are defined by volatility, caution, and strategic positioning. From oil prices reacting to geopolitical tensions to regional shifts in fuel and propane costs, here’s what matters most for Sioux Valley Coop members.

Crude Oil & Fuel Market Dynamics

Oil prices began the week with upward momentum, supported by concerns over sanctions on Russian oil exports. Brent crude rose to about $66.81 per barrel, while West Texas Intermediate (WTI) traded near $63.10, marking a 2% rebound. OPEC+ announced a modest production increase of 137,000 barrels per day for October—a slower pace than in recent months, signaling caution amid uncertain global demand.

Looking further ahead, S&P Global projects that crude could retreat to $55 per barrel by the end of 2025. Factors such as steady Russian exports, weaker-than-expected stockpiling, and slower demand growth are contributing to this bearish outlook.

For end users, retail prices remain mixed. Gasoline is showing a modest post-Labor Day rebound, with Midwest averages near $3.08 per gallon and Gulf Coast averages around $2.77 per gallon. Diesel fuel continues to climb, rising 2.6 cents in early September to a U.S. average of $3.73 per gallon, roughly 11 cents higher than a year ago. This increase is particularly relevant for South Dakota’s agriculture sector as fall harvest approaches.

Propane Market Landscape

Propane prices across South Dakota are steady as the heating season approaches. The state’s average propane price sits near $1.93 per gallon, with Sioux Falls reporting around $1.59 per gallon and Rapid City closer to $1.68 per gallon. By comparison, the U.S. national average stands at $2.57 per gallon.

While statewide EIA data will not resume until October, the regional stability reflects healthy domestic inventories and continued export demand balancing global supply flows. For members, this is a strong window to secure propane supply through prebuy or budget programs ahead of winter heating needs.

DEF (Diesel Exhaust Fluid) Watch

The DEF market remains under strain. Extended maintenance at major U.S. urea production facilities, coupled with tighter global supply, is limiting availability across several regions. These pressures are contributing to higher costs and more cautious purchasing behavior among fleets and agricultural operators. For Sioux Valley Coop members, planning ahead for DEF needs is critical to avoid supply disruptions during harvest and winter operations.

What This Means for Our Members

As of September 8, 2025, the energy landscape highlights three key takeaways:

Fuel: Crude oil prices are climbing short-term but may soften toward year-end. Diesel remains elevated, impacting ag and transport operations.
Propane: Prices are steady with South Dakota averages below national levels. Now is the ideal time to secure supply.
DEF: Supply tightness continues, requiring proactive planning to ensure operational reliability.

Sioux Valley Coop will continue to monitor these developments closely and provide members with updates, insights, and supply solutions to keep our communities powered locally.

Sources

Reuters – Oil prices gain as risks of sanctions on Russia offset OPEC+ output hike (Sept 7, 2025)
Reuters – S&P Global expects crude prices to hit $55 per barrel by year end (Sept 8, 2025)
Work Truck Online – September Diesel Trends Update (Sept 3, 2025)
Automotive Fleet – September Fuel Update: Prices Edge Up Despite Record Low Labor Day (Sept 2025)
U.S. Energy Information Administration (EIA) – Propane price data for South Dakota
Consult Energy – South Dakota and U.S. Propane Prices (Sept 2025)
Mansfield Energy – Navigating 2025’s U.S. DEF Supply Squeeze (June 2025)
JobbersWorld – U.S. DEF Market Faces Supply Strain Amid Plant Downtime (May 2025)