Posted on November 09, 2018 by Charles Morris
In marketing materials and press coverage of EVs, the first spec cited is usually range - the distance a car can travel on a single charge. Now that a new generation of EVs offers enough range for most drivers’ daily needs, prospective buyers should also start looking at efficiency - the amount of energy a car consumes per mile.
Above: Tesla's Model S (Image: Tesla)
The EPA rates efficiency in terms miles per gallon equivalent, or MPGe. This can be useful for comparing different models, but it doesn’t give a precise picture of efficiency, as the formula used to calculate it relies on average fuel cost figures. More analytically-minded consumers may prefer to look at a vehicle’s direct efficiency rating, which can be expressed in kWh per 100 miles or in miles per kWh.
Whatever metric you choose to use, you’ll find that Tesla’s vehicles offer significantly better efficiency than competitors of similar size. The recently released Jaguar I-Pace has a 90 kWh battery pack, 234 miles of range, and an EPA combined rating of 76 MPGe. The larger and heavier Model X with a 75 kWh battery offers 257 miles of range, and earns a 93 MPGe rating. Fox News reports, “Tesla clearly holds a significant advantage in power management, and should continue to do so through next year when the Audi e-tron, which is similar in size to the I-Pace, joins the fray with a 95 kWh pack and a range that’s likely to be less than 250 miles.”
Efficiency is important for a car buyer because it affects the total cost of ownership. As is the case with a gas vehicle, a more efficient car costs less to drive (although the cost difference is relatively small, as electricity costs on average about a third what gasoline does).
Above: Tesla's Model X (Image: Tesla)
Efficiency can also be a competitive advantage for an automaker (as Toyota or Honda would doubtless agree). If you consider the figures cited above, you’ll notice that Tesla’s superior efficiency allows it to deliver more range with a smaller battery pack. The company called attention to this in its third quarter investor letter, noting that efficiency is “an extremely important metric as it allows an EV to reach a long EPA range even when using a relatively small, inexpensive battery pack.”
During the earnings conference call, Elon Musk expanded on the subject, telling analysts that not only are Tesla’s powertrains the most efficient, but its batteries are also cheaper to produce. As InsideEVs noted, Tesla has been improving its battery packs and powertrains for the last 15 years, while the legacy carmakers waited to see what would happen.
It’s not just Model X that outclasses the competition in the efficiency department. Model 3 has earned an EPA rating of 116 MPGe, surpassing the 2016 Nissan LEAF (112 MPGe) and rivalling the smaller Chevy Bolt (119 MPGe). There are a few other EVs that beat Model 3 in efficiency, but as Tesla pointed out in its earnings report, none has all-wheel drive.
Above: Tesla's Model 3 (Flickr: Markus Spiering)
The cocky Californians cocked a snook at Audi’s upcoming AWD-equipped e-tron, pointing out Model 3’s energy efficiency of 4.1 miles per kWh, and noting that “our current or upcoming AWD (2019) competition is expected to achieve 2.4 to 2.8 miles of EPA range per kWh.” But wait, there’s more (there usually is): “Model 3 has far better energy efficiency while also providing the quickest acceleration (0-60 mph in as little as 3.3 seconds) and the highest top speed (155 mph). Additionally, the curb weight of Model 3 long range RWD is only 3% heavier than its gas powered equivalents.”
Written by: Charles Morris