The widening spread was a boon for sellers of refined products, which are typically priced to the global market. According to the Energy Information Administration, U.S. exported daily about 3.4 million barrels of refined products, including gasoline and diesel, as of May.

“They’re in the catbird seat as far as buying their raw materials,” Sandy Fielden, director of oil research for Morningstar Inc., told the WSJ, adding that refining was a “cash cow.”

ETF investors can also capitalize on the strength in this energy segment through targeted sub-sector ETF plays. For instance, the VanEck Vectors Oil Refiners ETF (NYSEArca: CRAK) is the only exchange traded fund dedicated to oil refiners. Additionally, the Invesco Dynamic Energy Exploration & Production Portfolio (NYSEArca: PXE), a smart beta spin on exploration and production names, and the iShares U.S. Oil & Gas Exploration & Production ETF (Cboe: IEO) both include smaller allocations to oil and gas refiners.

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