2019 BMW i3

2019 ASG AWARDS: Best Environmental Performance in the Mini-Compact segment.

NOTEWORTHY ASG FINDING: holds the smallest life-cycle carbon footprint in its class at 137 grams CO2-e per mile driven lifetime.



ASG’s annual study found the BMW i3 to hold the smallest carbon footprint in its class, earning ASG’s coveted BEST ENVIRONMENTAL PERFORMANCE award for the third consecutive year. The BMW i3 outperformed all Mini-Compact cars in a competitive segment that included 99 vehicle variants, producing 45% less CO2-e emissions over the first 6.5 years in its life-cycle, when compared to the average vehicle in its segment.

Unique to the BMW i series, carbon fiber reinforced plastic (CFRP) forms the body of i3, significantly reducing vehicle weight to compensate for the larger battery pack. BMW's light-weighting strategy allows the i3 to come in under 3,000 lbs. (curb weight), which is quite the design accomplishment for a battery electric vehicle.

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The Automotive Performance Index (API) applies statistical methods to demonstrate each vehicle rating in relative comparison. For example, the vehicle that performs highest in environment performance in a given class obtains a rating score of 100. Each vehicle in its class is then compared relative to the top-performing vehicle with a rating score reflecting the statistical difference in performance outcomes. A score of 91 translates to a 9% environmental performance deficit as compared to the top-performing vehicle.  

Due to the API’s relative vehicle rating method, vehicle class divisions were identified as a critical input - these class divisions are detailed here.

While the Automotive Performance Index is indeed an exhaustive list of vehicles to trim level detail, with each vehicle assessment reporting over 200 unique data outputs (the culmination of thousands of data inputs), ASG has taken additional measures to ease the burden of sorting through all data points and all vehicle assessments. We have developed key performance categories and sorted all vehicles in each class according to Environmental Performance, Social Performance, Economic Performance and All-Around Performance. The vehicle in each class with the best score in each unique category is named the performance award winner (i.e. Best Environmental Performance Award winner). The vehicle in each class that scores highest combined scores in Environmental Performance, Social Performance and Economic Performance is named the ASG Best All-Around Performance Award winner.

One step further, we also name the Best 5 All-Around Performance Award winners in each class to provide consumers with a concise product comparison guide.