Diesel is trading near $200 per barrel on the global market, according to Energía a Debate, and that level is driving up the cost of generating electricity that depends on that fuel in Mexico. On September 20, 2026, the Secretaría de Hacienda kept the IEPS diesel quota exempt and raised the complementary stimulus to 1.84 pesos per liter, according to El Economista.
The origin of the adjustment lies in the global market: refining capacity is running at its limit and diesel has decoupled from the price of crude. For Mexico, the effect goes beyond how much electricity is generated with that fuel. The country has installed capacity that uses it as a primary or secondary source, above all peaking plants, along with emergency plants that operate outside the Wholesale Electricity Market, explains the analysis by Energía a Debate. That capacity enters dispatch when demand rises, during a contingency, or when a transmission constraint forces the use of local generation, and at those moments it can set the marginal price for the region.
The cost difference is the point. An aeroderivative gas turbine running on diesel consumes about 1.6 barrels per MWh generated; with the fuel at $200 per barrel, that input alone comes to roughly $320 per MWh, compared with less than $50 per MWh for an equivalent unit running on natural gas. Generating with diesel costs six to eight times more today. The average Local Marginal Price went from 857 pesos per MWh between August 16 and 22 to 1,406 pesos between September 6 and 12, and in Cozumel and Riviera Maya it exceeded 15,000 pesos per MWh. Reforma reported on September 17 that the increase is squeezing the electricity bill of large industrial and commercial users, around 30% of market participants without a hedging contract, and that household bills do not adjust immediately.
What happens next depends on two variables: diesel holding near $200 per barrel, and the system again recording demand peaks or transmission constraints. The week of September 19 to 25 operates with a zero IEPS quota and a stimulus of 1.84 pesos per liter; El Economista calculated the liter at 36.21 pesos without those supports.
This article was written with the assistance of artificial intelligence from verified sources and reviewed by a human editor before publication.
