HOW MUCH FUEL DOES A HYBRID REALLY SAVE? A SAME-MODEL COMPARISON OF HYBRID AND GASOLINE CARS IN US FUEL ECONOMY

Abstract

Hybrid cars are usually advertised as economical, but the saving depends on the car and on how it is driven. This study compares hybrid and conventional gasoline versions of the same model in the official US fuel economy database of the Environmental Protection Agency and the Department of Energy. A hybrid was paired with a conventional car when both had the same make, base model, model year and drive type, which gave 497 pairs covering about 60 models from 23 makes and model years 2003 to 2027. Before seeing any results, I predicted that hybrids save more fuel in the city than on the highway, and that mild hybrids with small batteries and heavy, powerful vehicles that are driven mostly on the highway save almost nothing. For the median pair, a hybrid was rated to use 36% less fuel in the city, 14% less on the highway and 28% less in combined driving. The city saving was larger than the highway saving in 494 of 497 pairs and for all 60 models, and the result held when only versions with the same engine were compared. Twenty-one pairs saved less than 5% in combined driving. All of them were SUVs or pickup trucks, and twenty carried the database label "Mild Hybrid". In the nine pairs where the hybrid was rated to use more fuel, the hybrid version also had a larger engine than every conventional version, although one mild hybrid Jeep Wrangler was also worse than a conventional Wrangler with the same engine. Pickup trucks saved little even without the mild hybrid label. These are official test ratings, not measurements in real traffic, but they suggest that the size and purpose of the vehicle matter at least as much for fuel saving as the type of hybrid system.

Keywords: hybrid electric vehicles, fuel economy, mild hybrids, city and highway driving, EPA fuel economy data

References

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How to cite

Alniyaz D. HOW MUCH FUEL DOES A HYBRID REALLY SAVE? A SAME-MODEL COMPARISON OF HYBRID AND GASOLINE CARS IN US FUEL ECONOMY // Central Asian Scientific Journal. – 2026. – No. 4(32), Vol. 1. – Pp. 173–179.