Too complex. Work it like Provincial utilities. Set rate over a period of time with annual reviews. Shortages and surplus kept in check with a reserve.
This is the affects of not just sanctions on Russian diesel but the global marine shipping fleet was legislated into eco-mandates forcing the end of bunker fuel.
Xa-Xa! (Ruskie for Ha-Ha!)
Soooo how do you heat 10bbls of oil without burning anything to keep it cheap?
Fresnel lenses from projection TVs. Literally "death rays" for anything that "goes into the light".