BETs have roughly 40% lower energy consumption than their diesel counterparts (7.5 mpg, or 5.1 kWh/mi or 3.17 kWh/km). This is considerably lower than the efficiency gains for the light-duty sector. Electric LDVs have reported fuel efficiencies ranging between 0.23 and 0.55 kWh/mi (0.14 -0.34 kWh/km), resulting in savings of roughly 60 to 80% compared to gasoline engines (25.7 mpg 97 or 1.27 kWh/mi or 0.79 kWh/km). The lower efficiency gain can be explained by the higher efficiencies of compression ignition diesel engines, used in trucks, compared to the spark ignited gasoline engines used for passenger cars. Additionally, urban driving involves large amounts of braking that can be used to regenerate the battery. However, long-haul highway driving predominately features constant velocities leading to lower benefits from regenerative braking.