Refining Margin: Golden Age to Dark Age?
Note: LLS – Louisiana Light Sweet
Source: Purvin & Gerz margins produced for IEA, IEA Oil Market Report.
Cycle
SThis plot shows U.S. Gulf Coast margins for Light Louisiana Sweet (LLS) crude oil in a cracking refinery and the margin for heavy Mexican Maya crude oil (22 API) in a complex cracking and coking refinery.  Before the recession, Maya coking margins grew more than LLS cracking margins because of the increasing light-heavy crude and product price differentials shown on the previous slide.

SMargins have collapsed for both in 2009, with weak product demand, falling utilizations, and rising inventories.  Now, the Maya coking margin is not any higher than the LLS cracking margin, as Maya-LLS price differences have contracted sharply.  There is even some discretionary reduction in coking inputs.  In the past, the coker was viewed as a high-margin unit by refiners to be run flat out.

SWill the relative margins for coking refineries improve?  Much of the crude oil now off the market is heavy, and when it returns, heavy crude will be less attractive.  But with heavy production in decline in the Western Hemisphere and growth in conversion capacity, a return to the heady days of 2005-07 is unlikely unless world demand for residual fuel oil runs into difficulty because of quality issues such as reduced sulfur in bunker fuels.

SThe investment incentive for new coking units is not there currently.