IIHS tests some of the most popular and newest electrics and the results were eye opening. Wayne Gerdes – CleanMPG – Feb. 1, 2017 The crash tests that separated the front runners from the also rans. In an Insurance Institute for Highway Safety (IIHS) crash test release, the institute found two battery electric vehicles (BEVs) fell short of meeting the Institute's top crash test awards criteria, while two popular plug-in hybrids (PHEVs) achieved the results garnering them a 2017 TOP SAFETY PICK+ award. The two that fell short? The 2017 Tesla Model S and the BMW i3. The two that made the cut? The Chevrolet Volt and the Toyota Prius Prime. To qualify for an IIHS TOP SAFETY PICK, a vehicle must earn good ratings in all five crashworthiness evaluations — small overlap front, moderate overlap front, side, roof strength and head restraints — and have an available front crash prevention system that earns an advanced or superior rating. The "plus" is awarded to vehicles that meet all those criteria and also come with good or acceptable headlamps. 2017 Tesla Model S The Model S earns good ratings in all IIHS crashworthiness evaluations except the small overlap front crash test, in which it earns an acceptable rating. Despite lengthening the side curtain airbags to improve small overlap protection in the Model S, the test shows the safety belt allowing the dummy's torso to move too far forward. That allowed the dummy's head to hit the steering wheel hard through the airbag. Measurements from the dummy indicated that injuries to the head, along with the lower right leg, would be probable in a real-world small overlap crash of the same severity. The ratings for the Model S apply to 2016 and 2017 cars built after October 2016. Tesla says it made a production change on Jan. 23 to address the head-contact problem, and IIHS will test the updated vehicle for small overlap protection as soon as it can be delivered. The Institute was quick to point out that the Tesla Model S is a larger car and cannot be directly compared to the smaller and better performing i3, Volt and Prius Prime. Tesla's acceptable rating is based on a more severe crash than the good ratings of the lighter cars because of tis mass. Unless you hit a tree or immovable object. The very latest Model S, the P100D, fell short on roof strength, an area they had embellished back in 2013 when it easily passed the NHTSA roof crush test. The IIHS rating is based on a strength-to-weight ratio. The P100D has the same roof structure as other Model S versions but is heavier, due to a larger battery, so it earns an acceptable rating. The current version of the Model S hasn't yet been rated for front crash prevention. While automatic braking equipment comes standard, Tesla hasn't yet activated the software for all vehicles. The 2017 Model S isn't available with anything other than poor-rated headlights. Tesla says it is working with its supplier to improve the headlights, and IIHS will evaluate the new ones when they are available. 2017 BMW i3 The i3 fails to reach the winner's circle because it rates only acceptable in the head restraint and seat evaluation, which measures a vehicle's ability to protect against neck injuries in a rear crash. While such injuries are rarely fatal, they are the most common type of crash injury and can cause debilitating pain. The i3 earns good ratings in the other crashworthiness tests and is available with an optional front crash prevention system that earns an advanced rating. The system reduced the impact speed by an average of 9 mph in the 12 mph track test and by 7 mph in the 25 mph test. Its warning component meets National Highway Traffic Safety Administration criteria. The i3's only available headlight system earns an acceptable rating. 2017 Chevrolet Volt The 2017 Volt can be optionally equipped with either an advanced- or superior-rated front crash prevention system. It earns a good rating for headlights when equipped with optional high-beam assist, which automatically switches between high beams and low beams based on the presence of other vehicles. Without high-beam assist, the Volt's headlights are acceptable. 2017 Toyota Prius Prime The Prius Prime is the PHEV variant of the Prius hybrid, also a TOP SAFETY PICK+ winner. Its standard front crash prevention system earns a superior rating, and its only available headlights earn an acceptable rating. IIHS plans to test another green car, the all-electric Chevrolet Bolt, once it becomes widely available later this year.