Oil prices rallied on Wednesday after the U.S. government reported a bigger-than-expected drop in crude stockpiles, but there's trouble brewing elsewhere in the energy complex.
A large surge in gasoline inventories last week, pared with a rise in refinery activity, compounded worries that a fuel glut will hurt future demand for crude oil, the feed stock for most fuels. That could frustrate efforts to balance an oversupplied market and send oil prices lower later this year.
The Energy Information Administration reported that U.S. gasoline stockpiles rose by 3.4 million barrels, versus expectations for a 1 million-barrel decrease in a Reuters poll.
Meanwhile, the nation's refiners increased their activity even as demand for gasoline softened last week. They were operating at 94.1 percent of capacity, the highest level since November 2015, according to Reuters.
"They're cranking out a lot of fuel here in the face of demand that is lackluster. They could be building a glut for themselves on the other side of the refinery," said John Kilduff, founding partner at energy hedge fund Again Capital.
The inventory build is in part due to refiners ramping up production earlier than usual, in Kilduff's view. However, the increase is somewhat unusual for this time of year and remains a concern because gasoline is heading into a period when it should be the "seasonal leader" among energy commodities, he said.
"To the extent that this is going to undermine gasoline price strength, it's bad for the complex," Kilduff said.
Tom Kloza, global head of energy analysis at Oil Price Information Service, noted that international benchmark has recently gone further into contango, a structure in which the future price of a commodity is higher than the current cost. That is the opposite of what one expects when the market is tightening, he said.
OPEC and 11 other oil-exporting nations including Russia are currently trying to reduce a global glut by cutting 1.8 million barrels a day of production in the first half of 2017. But Kloza said high U.S. refinery activity risks worsening a glut of gasoline, diesel and jet fuel.
"The bottom line for me is I can't believe how high and hard we are running refineries, and I think ultimately that's going to sabotage the gasoline market because we keep seeing gasoline demand that is consistently below last year," Kloza said.
Analysts also worry that weak gasoline demand will cause refiners' profit margins to drop to a level that will cause them to reduce their activity later this year, further denting oil demand.
"From our perspective, the crack spread — the profitability of refining crude products — has just dropped below year-ago levels and yet we're seeing refinery runs hitting an absolute high last week of over 17.3 million barrels a day, and so it is a concern," said Matt Smith, director of commodity research at tanker-tracking firm ClipperData.
While crack spreads are lower than at this time last year, they are still sufficient enough to incentivize refiners to keep turning out fuel, Smith said. That suggests that refinery activity is not being driven by demand for gasoline, but by abundant supplies of crude oil that refiners need to burn through, he added.
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