“The reason diesel is more expensive in the United States is a bit difficult to nail down...”
diesel is a collection of heterogeneous hydrocarbon chains.
Gasoline is a collection of more homogenous chains.
Diesel takes less refining of a barrel of oil...but results in less salable product because a lot more hydrocarbon chains that could be sold for other uses are being put through the engine.
Gasoline is more refined..takes more work to make..but has more leftovers to use elsewhere.
When demand is strong for hydrocarbon products in general, diesel is more expensive because of lost opportunity to the refinery-they’re selling you stuff they could sell elsewhere if you bought gasoline.
When demand is weak for other hydrocarbon products, diesel is a bit cheaper relative to gasoline-because they don’t have to expense the more extensive refining costs to you.
Thanks. Freepers are so smart!