how does the Prius measure fuel consumption and calculate its gas mileage?
We can find lots of info from US government’s Fuel Economy website. Excerpt “Fuel economy is measured under controlled conditions in a laboratory using a standardized test procedure specified by federal law. Manufacturers test their own vehicles—usually pre-production prototypes—and report the results to EPA. EPA reviews the results and confirms about 10-15 percent of them through their own tests at the National Vehicles and Fuel Emissions Laboratory.” Cars, including Prius, are tested in this way. How Vehicles are tested is insightful on this subject matter. Run through the “slides” and the video. Dynamometer is used. The car runs on a schedule (standardized driving routine) by professional driver. A hose connecting tailpipe will collect the engine exhaust, which will then be measured carbon content. Fuel consumption is then calculated. See EPA detailed test information for different “schedules” of different tests needed. 2010 Fuel Economy Guide is available now. We can check Prius da
