The duration that 20 cubic feet of fuel lasts depends on several factors, including the type of fuel, the efficiency of the engine, and the driving conditions. Generally, 20 cubic feet of fuel can last anywhere from 200 to 400 miles, depending on these variables.

The duration is influenced by the fuel efficiency of the vehicle. For instance, a car with an average fuel efficiency of 20 miles per gallon (mpg) would travel approximately 400 miles on 20 cubic feet of fuel. Conversely, a vehicle with a fuel efficiency of 10 mpg would only travel about 200 miles on the same amount of fuel. This discrepancy highlights the significant impact that fuel efficiency has on fuel consumption and overall range.

Data from the U.S. Environmental Protection Agency (EPA) provides insight into the average fuel efficiency of vehicles. In 2021, the average fuel efficiency for new vehicles in the United States was around 25 mpg for combined city and highway driving. Using this figure, a vehicle with a fuel efficiency of 25 mpg would travel approximately 250 to 500 miles on 20 cubic feet of fuel, depending on the driving conditions.

Driving conditions also play a crucial role in determining how long 20 cubic feet of fuel will last. For example, driving at higher speeds, in stop-and-go traffic, or carrying heavy loads can decrease fuel efficiency and, consequently, the distance traveled on a given amount of fuel. Conversely, maintaining a steady speed and avoiding unnecessary acceleration can improve fuel efficiency and extend the range.

In addition to these factors, the type of fuel being used can also affect the duration of 20 cubic feet of fuel. For instance, gasoline and diesel have different energy densities, which means they provide different amounts of energy per unit volume. Generally, diesel fuel has a higher energy density than gasoline, which can result in a longer range per unit volume of fuel.

In conclusion, the duration that 20 cubic feet of fuel lasts varies depending on the fuel efficiency of the vehicle, driving conditions, and the type of fuel being used. On average, a vehicle with a fuel efficiency of 25 mpg can travel approximately 250 to 500 miles on 20 cubic feet of fuel, but this can vary significantly based on the specific circumstances.