How to Use GreenerCars

What's Inside? gives you access to our database of every vehicle we have scored for the past fifteen years (model years 2000-2021; more than 20,000 records). Visitors can search the interactive database (updated with new model releases throughout the year) and build custom lists for comparing vehicles. 

Can't Find the Vehicle you are looking for on our Website?

Our free website and database includes the year's greenest and meanest vehicles, as well as the greenest vehicles in each size class, given in the best of 2021 database. 

Green Scores for Used Cars?

In addition to the model year 2021 listings, ACEEE's also contains ratings for all model year 2000 through 2021 vehicles. Ratings for model year 1998 and 1999 vehicles are available in hard copy in the 1998 and 1999 editions of ACEEE's, respectively. These can be purchased through the ACEEE publications office. Ratings for older vehicles (model year 1997 and earlier) are not available. For earlier model years, fuel economy is an important determinant of greenness. So look for high-efficiency models on the federal fuel economy guide website.

How to Buy Green will help you select the vehicle that is most friendly to the planet while meeting your transportation needs. Based on official emissions and fuel-economy tests, and other specifications reported by auto manufacturers, we calculate a Green Score for each car, minivan, pickup, and SUV on the market. The Green Score falls on a scale of zero to 100. A higher score implies a greener car, meaning a vehicle having a lower environmental impact.

Green Scores and Class Rankings

In our database, vehicles can be searched by class (that is, the type or body style, such as midsize car, minivan, standard pickup, and so on). To summarize our ratings and make it easy to find the top-rated vehicles in each class, we use a five-tier class ranking—superior, above average, average, below average, and inferior—depending on where a model falls within its class. No vehicle gets a superior rating if its Green Score is worse than the overall average of all vehicles offered this model year, even if it ranks among the best in its class. Look for models that are ranked superior or above average to easily find those that have the greenest scores.

To make it easy to find the most planet-friendly new cars and trucks available this year, our highlights identifies not only the overall greenest vehicles of 2021, but also the models with the highest Green Scores in each class, "the best of 2021." The easiest way to buy green is to select a vehicle from this "best of 2021" list.

If you'd like to see more than just the models in the "best of 2021" list, use the database to get details for every make and model now on the market (as well as all model year 2000 through 2021 vehicles). Our online database lists each vehicle's emission standard, fuel economy, fuel costs, health effects, carbon dioxide emissions, and overall environmental impact, along with its Green Score and class ranking. If you have identified a set of models to consider, build a comparison list in the database to comparison shop with the environment in mind.

For most consumers, the Green Score and class ranking provide a good indication of a vehicle's environmental performance. Full details on how our Green Scores are calculated are found in "Rating the Environmental Impacts of Motor Vehicles: ACEEE’s Green Book Methodology," which can be downloaded for free from ACEEE's publications site. In general, a vehicle is greener if it is cleaner (having lower pollution) or more fuel efficient (resulting in lower energy consumption and carbon dioxide emissions).

Different versions of a model have different Green Scores

Nearly all models come in different configurations, meaning different choices of engine, transmission, and other major options. A model may also be available in versions that meet different emissions standards or run on alternative fuels.

To match a model in the showroom with a listing, first match its engine size and transmission type (automatic, manual, 4wd, etc.), followed by the city and highway fuel economy ratings found on the vehicle window label. Lastly, examine the window sticker or underhood ID to match the vehicle's emission standard.