2019 ASG AWARDS: Best 5 All-Around Performance

NOTEWORTHY ASG FINDING: Among the best 5 mid-large size cars in 2019, rising to the top of a crowded segment that includes 434 variants.



The Toyota Prius Eco again rises to the top of ASG’s 2019 API, earning ASG’s Best 5 All-Around Performance honor, just as it counts its 19th year since it was introduced to the North American market. When the Prius was first launched in the U.S. market in 2000, the world’s first mass-produced hybrid boasted of its 41 MPG combined (city/hwy). With a 117.5 lb. NI-MH battery pack and a curb weight of 2765 lbs., Toyota lead the industry into the hybrid era. 19 years later, the Prius Eco is equipped with a lighter lithium Ion battery that achieves 56 MPG combined – a notable 15 MPG improvement.

To see what this improvement means in CO2 terms, ASG conducted a comparative life-cycle assessment, and found the 2000 Prius to hold 295 grams of CO2-e emissions per mile driven life-time (accounting for resource extraction, processing, vehicle assembly, delivery, use and upstream fuel phases). ASG found the 2019 Prius Eco to hold 241 grams of CO2-e emissions per mile driven life-time, a 18% reduction over the 2000 model and a significant stride without a full technology leap.

While this is notable, the model that places the Prius at the #1 position of ASG’s 2019 API, is the Prius Prime. Toyota is bridging the technological gap once again and leading us into the battery electric era with this plug-in hybrid model, featuring 133 MPG-e and a 25-mile all-electric capability. According to ASG, this lithium-ion plug-in hybrid model holds 154 grams of CO2-e emissions per mile driven life-time, a life-cycle carbon footprint that is 48% less than the first generation Prius.

Compare Prius’ evolution with that of other top selling cars in North America and one sees a very different arc in CO2 emission reductions over the past two decades.

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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.