Many people throughout the country notice that gas prices rise a little around Memorial Day. You may think it’s because Memorial Day marks the beginning of summer vacations, which typically include road trips, and it’s just a way to make some more money with the increased driving. Right now, of course, we also have some inflation to factor in as well as some precariousness in the crude oil markets. But gas prices increase in the summer only in part by the supply and demand changes. The bigger reasons are that a lot of energy companies shut down refineries in the early spring while they conduct maintenance and summer-blend fuels are more expensive to make. Usually, gas prices are the lowest in February and peak around Memorial Day.
The National Association of Convenience Stores’ (NACS) Advancing Convenience & Fuel Retailing Department tells us that “refinery maintenance, known as a ‘turnaround,’ is often scheduled during the first quarter. A turnaround is a planned, periodic shut down (total or partial) of a refinery process unit or plant to perform maintenance, overhaul and repair operations and to inspect, test and replace materials and equipment.” Each refinery goes through this process every one to four years, which translates to about 25% of refineries being shutdown each spring. They also perform this turnaround to retool fuel for the summer blend, which occurs throughout March and April in order to be ready for the summer months ahead. Then in May and June, terminals must start to purge their systems of winter-blend fuels. This often leads to lower supply at the pump, resulting in higher prices. Some areas of the country must have this purge completed by May 1, but others may have until June 1 to complete the switch. Combine this process with demand increases, and factor in some other possible stresses to the system (such as an outage), and you have rising gas prices during the summer, especially in May.
When autumn hits, the demand decreases a bit and retailers are able to switch to winter-blend fuels, typically beginning September 15. We often see decreased prices at this time, however, complications from the switchover can temporarily bump prices again. Certain weather conditions or natural emergencies, such as hurricanes or forest fires, can also affect prices.
NARCS states that summer-blend fuel is “more expensive to make than winter-blend fuel. First, the production process takes longer and, second, the overall yield of gasoline per barrel of oil is lower. These complexities add as much as 15 cents per gallon to the cost to produce these higher-grade fuels.”
As you can see, there are multiple reasons for the fluctuation in fuel prices throughout the year. During the hot summer month, consider summer-specific additives for diesel and regular gasoline engines to keep your vehicle running optimally. Diesel Fire is a demulsifier additive that is specially designed for diesel engines in warm weather. Phaze-Out is a great regular gasoline option for an additive any time of year, including summer.