Trips to the gas pump will be few and far in between for the 2021 RAV4 Prime. Its state-of-the-art plug-in hybrid system combines two electric motors with a 2.5-liter four-cylinder engine, delivering an estimated efficiency rating of 90 MPGe. Also, the RAV4 Prime can run on electric-only power for an estimated 39 miles. This is the highest electric range for the plug-in hybrid SUV segment.