Countercurrent
by Cape Island Point Research
Banning diesel exports would raise your gas bill, not cut it
By Brandon · September 30, 2026
The short version: a ban sounds like it keeps cheap diesel at home. In practice it gives refiners a reason to make less of everything, including the gasoline in your car.
The consensus
Diesel hit a record $6.53 a gallon on September 22, up about 77% from a year ago, and U.S. diesel stockpiles are the lowest in more than 40 years. The U.S. is the world's largest diesel exporter, shipping out the equivalent of about 40% of what we burn at home. So the pitch writes itself: stop sending it overseas and prices here will fall. Bills in Congress would ban exports through January 2027 or trigger limits at $5 a gallon, and the Energy Secretary has reportedly asked refiners about holding back voluntarily. The White House says it isn't preparing a ban, but the idea is gaining support ahead of the midterms.
Why I think it backfires
A refinery doesn't make diesel by itself. Every barrel of crude is split into gasoline, diesel, jet fuel and other products at the same time; a typical U.S. barrel yields roughly 19 to 20 gallons of gasoline and 11 to 12 of diesel. If refiners lose their best-paying buyers for diesel, the rational move is to run less crude. That cuts diesel and gasoline. Industry analysts estimate a ban could trim U.S. refinery runs by as much as 750,000 barrels a day.
This isn't a crude oil problem. Of diesel's $2.25 rise since February, only about 68 cents came from crude. The rest came from refining margins, driven by a global shortage: Russia has nearly stopped exporting fuel after attacks on its refineries, and disruption around the Strait of Hormuz cut Gulf exports. U.S. refineries are already running at about 97–98% of capacity, and three closures since early 2025 removed 550,000 barrels a day. There is no spare plant to make more. A ban doesn't add a gallon of capacity.
Refiners pay world prices either way. Crude is priced globally. Trapping diesel at home doesn't lower what a refiner pays for its oil; it lowers what it can earn on what it makes. Less reward means less output.
We've run this experiment before. Price and supply controls in the 1970s produced gas lines and odd-even rationing, not cheap fuel.
What it means for Charleston
The East Coast is the tightest region in the country, with diesel stocks about 35% below normal. Most of our fuel comes from Gulf Coast refineries by pipeline and tanker, and those routes are already stretched. Diesel that can't be exported would mostly pile up near Gulf refineries, not show up at a terminal on the Cooper River. Meanwhile the port, the trucks on I-26 and every construction site run on diesel. South Carolina gasoline averaged $4.10 this week versus $4.48 nationally; I'd expect that gap to narrow, not widen, if a ban cuts refinery runs.
What would change my mind
If a ban passes and refiners keep running near capacity anyway, perhaps because domestic diesel demand is strong enough to absorb the extra supply, pump prices could hold or even dip. If gasoline is cheaper a month after a ban than the day it starts, the refinery math I'm leaning on mattered less than I think, and I'll come back and say so.
What I'm watching
- EIA's weekly refinery utilization. A drop from 97% into the low 90s after any restriction would be the tell.
- East Coast distillate stocks heading into winter heating season.
- The futures curve. New York Harbor diesel is priced near $5.00 for October but about $3.54 a year out, so the market already expects relief without a ban.
Disclosure: I have no direct position in refiners, oil producers, energy funds or fuel futures. I own broad S&P 500 index funds, which include small holdings in energy companies. This is general market commentary, not personal investment advice.
Sources: EIA, What goes into diesel prices (Sept. 18, 2026); AgManager, Why diesel prices are so high (Sept. 14, 2026); Al Jazeera, What would a US diesel export ban mean (Sept. 25, 2026); Chase, Diesel prices hit new record; AAA via ABC Columbia (Sept. 28, 2026).