2018 BMW i3

The BMW i3’s performance in the Automotive Science Group’s (ASG) 2018 Automotive Performance Index™ (API) Study, proves the benefits of BMW’S innovative approach that combines light-weighting strategies with advanced battery electric technologies. The Study found the BMW i3 to hold the smallest carbon footprint of any car in its class, earning ASG’s BEST ENVIRONMENTAL PERFORMANCE award in the Mini-Compact segment.

ASG’s environmental performance analysis is a comprehensive data-driven life-cycle assessment, analyzing environmental factors that include raw material extraction and production, vehicle manufacturing and assembly, vehicle distribution, fuel source production and distribution, in addition to tailpipe emissions for internal combustion engines.

ASG develops a life-cycle model for each new vehicle, and assesses vehicle performance in Gross Energy Requirements (GER) and CO2-equivalent emissions, thereby providing a platform for environmental performance comparisons across all technologies available to consumers in North America.

BMW i3 earned the class leading environmental performance rating, outperforming the average car in its segment by producing 38% less CO2-e emissions over the first 6.5 years in its life-cycle. The i3’s all-electric capabilities, with a 114-mile all electric driving range, leverages the increasingly cleaner U.S. power grid as a fuel source to significantly increase the environmental benefits of the battery electric powertrain in 2018, and across future years.

The BMW i3 leverages an efficient electric powertrain to deliver low emission transport in the Mini-Compact segment. The I3’s EPA estimated 118 MPG-equivalent rating (MPG combined) and its effective light-weighting strategy that leverages carbon fiber, gives the i3 a significant weight advantage across the segment, coming in at 358 pounds lighter than the average curb weight in class. Less resources translates to reduced environmental footprint, increased operational efficiency and reduced life-cycle operating costs.

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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.