USWC Summer Gasoline Shift Raises Supply Risks


   
Kristina Davis
DTN Refined Fuels Market Reporter

    

   MIAMI, FL (DTN) -- The U.S. West Coast gasoline market is entering the 
summer driving season under growing pressure as tighter fuel specifications, 
refinery closures and geopolitical risks combine to create a more fragile 
supply system heading into peak demand months.
California's transition to lower Reid Vapor Pressure (RVP) gasoline blends is 
adding another layer of complexity for refiners already operating with reduced 
capacity. During the summer months, refiners must produce cleaner-burning 
gasoline with lower volatility to meet California Air Resources Board standards 
designed to reduce evaporative emissions during hotter weather.

   The lower-RVP gasoline is more expensive to manufacture because refiners 
must limit the use of cheaper blending components such as butane while relying 
on tighter blendstock specifications.
The seasonal fuel quality shift comes as the region has lost key refining 
capacity over the past year. Phillips 66 shut its 139,000 bpd Los Angeles 
refinery in late 2025, while Valero has been idling its Benicia refinery 
through a phased shutdown process that began earlier this year. The Benicia 
refinery, which processes roughly 145,000 bpd of crude oil, had been a major 
supplier of gasoline into Northern California markets.
Other large facilities, including Chevron's El Segundo and Richmond refineries, 
Marathon Los Angeles and PBF's Torrance and Martinez plants, continue operating 
but some of them have also planned turnaround in the first half of the year.

   USWC fuel traders say the system now has far less flexibility to absorb 
outages or unplanned disruptions during summer demand season.
Last year, Chevron's El Segundo refinery experienced some of the region's most 
intense flaring activity after a fire at the Isomax 7 unit forced multiple 
operational shutdowns and tightened jet fuel supply across the West Coast.

   While refinery flaring activity across the USWC has eased compared with late 
2025, traders argue the decline reflects reduced refinery operations rather 
than improved system stability.
The tighter refining system has already started surfacing in prices. Since the 
start of the Iran conflict on February 28, Los Angeles ULSD spot values have 
climbed roughly 68%, while Los Angeles jet fuel and CARBOB gasoline values have 
increased about 59%, according to DTN pricing data.
Retail fuel prices have also strengthened sharply across the region. West Coast 
regular gasoline averaged roughly $5.22 gallon in early May, according to 
Energy Information Administration data, marking the highest level since October 
2022 during the Russia-Ukraine energy crisis.

   The U.S. Senate is, meanwhile, expected to vote next on a Congress-approved 
bill to permit year-round nationwide sales of E15, the gasoline with 15% 
ethanol versus the regular E10, which contains10% ethanol. While proponents 
argue the discounted blend could lower costs, California refiners note that 
aligning the federal mandate with the state's rigorous CARBOB and Tier 3 
standards remains a significant technical and regulatory hurdle.

   Inventories and imports
Inventories heading into summer also remain relatively tight. EIA data showed 
PADD 5 gasoline inventories increased by 100,000 bbl to 28.3 million bbl during 
the week ended May 8, after rising the prior week. Gasoline imports in the 
region fell by 131,000 bpd to 121,000 bpd last week and were 127,000 bpd lower 
compared with the same week last year.

   Last summer, West Coast gasoline inventories climbed above 30 million bbl 
during parts of June and July as refiners increased seasonal gasoline 
production.

   Imports are expected to play a key role balancing the market this year. 
California Energy Commission (CEC) data show the state imported gasoline and 
blending components from countries including South Korea, India, Taiwan, the 
Bahamas and several European suppliers last year as refiners supplemented local 
production.
The region also continues relying heavily on imported crude feedstocks. 
According to CEC data, Brazil, Iraq, Guyana, Canada and Ecuador ranked among 
the largest crude suppliers into California last year, with Canadian medium and 
heavy grades remaining important for optimizing gasoline and diesel yields at 
complex West Coast refineries.
The escalation involving the Strait of Hormuz could further amplify gasoline 
price risks for California drivers, who already face some of the nation's 
highest fuel prices due to stricter fuel standards and limited refining 
capacity. With the extension of the Iran conflict, underlying supply conditions 
remain increasingly fragile as the USWC fuels market moves deeper into 
summer-grade gasoline production.

    

    




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