May 31, 2018

Wise yet nimble at 18 years, according to ASG

31 May 2018 [Santa Rosa, CA] – The Automotive Science Group (ASG) released findings today from its annual Automotive Performance Index (API) study, with the Toyota Prius Prime topping the index, and earning ASG’s Best All-Around Performance title. In the 18th year since the Prius was introduced to the North American market – the Prius has finally come of age.
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 with this compact model. 18 years later, the Prius Two 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 (attributing CO2 emissions from raw material extraction, processing and manufacturing, through vehicle use with fuel inputs, to vehicle end-of-life). ASG found the 2018 Prius Eco to hold 226 grams of CO2-e emissions per mile driven life-time, a 23% 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 top of ASG’s 2018 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 181 grams of CO2-e emissions per mile driven life-time, a life-cycle carbon footprint that is 39% 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. One such example - the Ford Taurus had an EPA estimated 20 MPG combined in 2000, and a rating of 21 MPG combined in 2018. Mind you, that’s 1 MPG improvement in 18 years. ASG’s comparative life-cycle assessment shows the 2018 model with a 4% reduction in life-cycle carbon emissions at 556 grams CO2-e emissions per mile driven life-time. One can see that light-weighting was clearly not in the Taurus’ evolution, with a car that has added 525 pounds to its waistline, while also managing to lose passenger volume by 2 cubic feet.
There are many other examples - the 2018 Honda civic is up a mere 3 MPG combined since the 2000 model year; the 2018 Chevrolet Impala is up 4 MPG combined; the Nissan Sentra is up 6 MPG combined. A large segment of America’s top selling cars have in fact failed to innovate, simply repackaging the same technologies with only modest improvements over a significant time lapse. When looking at these meager fuel economy gains as evidence, one could nearly agree with the new Administration’s planned freeze on Obama era fuel economy targets.
But, then there’s the leaders in the industry and their cost-effective achievements, which altogether torch the Administration’s case for a freeze. Rest assured, 2018 brings innovation in the form of new models that simply weren’t available in times past, like the Hyundai IONIQ Hybrid and IONIQ Plug-in, the Tesla Model 3, Nissan Leaf, Chevrolet Bolt and Ford Focus Electric, to name a few of ASG’s top selections for 2018.
According to ASG’s 2018 Study, advanced powertrains are not only available to the masses in record numbers in 2018, and with exceptional environmental performance, but the leading models actually break from the pack to offer industry leading economic performance and best all-around value in class. Case in point - the all-new 2018 Hyundai IONIQ Hybrid with 58 MPG combined (city/highway) and with a starting MSRP at $22,200 is ASG’s 2018 Best Economic Performance selection in the full-size class. The IONIQ Plug-in also earned the Best Environmental Performance and Best All-Around Performance awards for an IONIQ sweep in the full-size class for 2018.
While ASG’s study reveals that these advanced powertrains are largely responsible for leading significant fleet fuel economy gains in 2018, there is one notable model with a conventional powertrain that is a standout in the API. ASG found the Mitsubishi Mirage to hold the smallest life-cycle carbon footprint of any conventional powertrain, at 301 grams CO2-e per mile driven life-time - this is on par with the Audi A3 Sportback e-tron and Ford Fusion Hybrid at 297 grams and 295 grams respectively.
But the Mirage holds an ace when compared to these models, it also holds claim to the lowest cost of ownership and best economic performance of any model year 2018 car in the North American market, earning ASG’s Best Economic Performance award for the second consecutive year. The Mirage maximizes the fundamentals of utility - with sizable passenger volume, a light-weight design, and a fuel efficient 1.2 liter inline 3-cylinder engine that achieves 39 MPG combined, the best MPG rating of any 2018 vehicle without hybrid or electric capabilities.
Mitsubishi has found a winning combination that it has implemented across its North American lineup, one that adheres to the engineering principles embodied in the Mirage – Mitsubishi builds cars and SUVs with a streamlined light-weight vehicle architecture, with fuel efficient engines that reduce operating costs and carbon emissions, and with MSRP’s that cut the competition. By adding a Plug-in powertrain to the 2018 Outlander SUV, Mitsubishi reveals a smart path for a brand with boundless potential.
In ASG’s data-driven brand assessment, ASG assessed all model year 2018 vehicles under 33 brands, to identify the consistency of performance across all brand offerings. ASG found Mitsubishi models with the highest consistent performance across all models, earning Mitsubishi the Best Economic Performance Brand and Best All-Around Performance Brand of 2018.
Tesla’s impressive lineup that includes the Model S, Model X and Model 3, earned ASG’s Best Environmental Performance Brand. While the Model 3 trails the Prius Prime with a 4% carbon deficit at the 6.5-year mark in its life-cycle (time and vehicle miles traveled for the average new car buyer), it outperforms the Prius Prime by 11% with the lowest carbon footprint of any 2018 model over its full life-cycle.
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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.