Hoping to decrease your carbon footprint and live a greener life? What and how you drive is a large part of your daily carbon footprint. Battery electric vehicles, several hybrid options and even traditional internal combustion engines have become more efficient and emit fewer greenhouse gasses. Greenhouse gases are any of the atmospheric gases that contribute to the greenhouse effect by absorbing infrared radiation produced by solar warming of the Earth's surface. These include include carbon dioxide (CO2), methane (CH4), nitrous oxide (NO2), and water vapor. Even if you’re not in the market for a new car, conduct your own research to find out what cars get the best fuel efficiency and minimize greenhouse gases. You may be surprised.
Vehicles are driven over identical driving patterns by professional drivers in controlled laboratory conditions on a dynamometer, which is like a treadmill for cars. The conditions that occur during driving, such as wind drag and inertia are accounted for on the dynamometer. There are two types of tests that are conducted: city and highway tests.
The city test is approximately 11 miles long and simulates a stop and go trip with an average speed of about 20 miles per hour (mph). The trip lasts 31 minutes and has 23 stops. About 18 percent of the time is spent idling (as in waiting for traffic lights). A short freeway driving segment is included in the test. The engine is initially started after being parked overnight.
The highway simulates a 10 mile trip with an average speed of 48 mph. The vehicle is started "hot" and there is very little idling and no stops.