The scores are based on the environmental damage index (EDX).
The greenest of all is the Hyundai Ioniq EV.
The anti-greenest is the Ram 1500 TRX. Its EDX is nearly 4.5 times greater than the Ioniq.
Determining the greenest of the green and the meanest of the not-so-green vehicles requires a deep dive into every step involved in making a vehicle. When all of these factors are put into context, it is possible to determine the cleanest of them all. It’s also easy to point the finger at the dirtiest of them all as well.
For 24 years now, GreenerCars has released its rating. Every year, hundreds upon hundreds of vehicles are given a green score. It is with this data these lists can be compiled. The nonprofit American Council for an Energy-Efficient Economy (ACEEE) explains what the green score is:

The Green Score is “based on an environmental damage index (EDX), which reflects the cost to human health from air pollution associated with vehicle manufacturing and disposal, the production and distribution of fuel or electricity, and vehicle tailpipes.”
There are three categories and they are broken down as follows: Greenest, Greener Choices, and Meanest. The names clearly identify the positioning of the new vehicles on the lists. And so, here are the Top 12 members of each list:
Greenest (EDX)
1-Hyundai Ioniq EV (0.60)

2-Mini Cooper SE 2-door EV (0.61)

3-Toyota Prius Prime (0.64)

4-BMW i3s EV (0.65)

5-Nissan Leaf (0.66)

6-Honda Clarity PHEV (0.70)

7-Hyundai Kona EV (0.71)

8-Kia Soul EV (0.72)

9-Tesla Model 3 Standard Range Plus (0.75)

10-Toyota RAV4 Prime (0.76)

11-Toyota Corolla Hybrid (0.76)

12-Honda Insight (0.77)

Greener Choices
1-Toyota Camry Hybrid LE (0.80)

2-Hyundai Sonata Hybrid (0.80)

3-Honda Insight Touring (0.85)

4-Toyota RAV4 Hybrid (0.96)

5-Chevrolet Spark (1.03)

6-Kia Sorento Hybrid (1.04)

7-Kia Soul Eco Dynamics (1.09)

8-Toyota Sienna (1.11)

9- Toyota Highlander Hybrid (1.11)

10-Mazda MX-5 (1.16)

11-Mercedes-Benz GLA 250 (1.24)

12-Volvo V90 FWD (1.27)

Meanest
1-Ram 1500 TRX (2.80)

2-Lexus LX 570 (2.41)

3-Mercedes-AMG G 63 (2.39)

4-Toyota Land Cruiser (2.32)

5-Toyota Sequoia (2.32)

6-Toyota Tundra (2.28)

7-Dodge Durango SRT (2.23)

8-Jeep Grand Cherokee SRT (2.23)

9-Range Rover SVA (2.23)

10-BMW X5 M (2.23)

11-BMW X6 M (2.20)

12-Dodge Challenger SRT Widebody (2.18)


