At Witz' End: The more I drive it, the more the Nissan Leaf is (and isn't) like an EV1
by Gary Witzenburg on Nov 12th 2010 at 11:51AM 
Nissan Leaf EV – Click above for high-res image gallery
I've written about the ways that the Nissan Leaf and the General Motors EV1 are similar before, but whiledriving a Leaf recently on lovely country (and some city) roads around Nissan's Franklin, TN headquarters, I was struck once again by the similarities between it and the General Motors EV1 of 14 years ago ... and the stark differences.
Like the long-gone EV1 (the first series-production pure electric vehicle (EV) from a major maker since the industry's early days), this state-of-the-art 2011 Leaf runs – very well – on battery power only. It accelerates quietly, briskly and smoothly with no transmission shifting. Its extensive instrumentation includes the EV basics of vehicle speed, battery state of charge (SOC) and, most importantly, range. In the minus column, its range is limited, and it takes hours to recharge.
That's about it. And most of that can be said about any BEV. Much more striking are the differences, and we get into that after the jump.
The Leaf is a practical 5-passenger compact hatchback with an excellent aero drag coefficient (Cd) of 0.29, compared to the much-less-practical raindrop-shape, two-seat EV1's astounding 0.19 Cd. The Leaf's 600-lb. lithium-ion manganese battery pack holds 24 kWh of energy vs. the EV1's 1,175-lb. "advanced" lead-acid pack's 16 kWh.
The Leaf's standard features include GPS navigation, Bluetooth phone connectivity, a sophisticated remote access interface (via smart phone) to set and check charge status, operate climate controls, etc. and a comprehensive suite of safety features that includes six airbags, vehicle stability control, traction control and ABS braking. EV1 had the world's first mobile heat-pump HVAC (which could be pre-programmed to heat or cool the cabin off the grid in advance) but few other state-of-the-art features common today.
Other interesting comparisons (Leaf figures listed first, then the EV1):
- curb weight – roughly 3,600 lbs. vs. 2,970 lbs. (of which 40 percent was the battery pack).
- drive motor – 80 kW (114 hp) vs. 96 kW (137 hp).
- acceleration – about 10 seconds 0-60 vs. eight seconds.
- top speed – 90 miles per hour vs. the EV1's (governed) 80 mph.
- range – nominal 100 miles (on California's test cycle) vs. 50-70, depending on temperature, terrain, accessory load and driving style.
- recharge time – about eight hours vs. three to four on 240V.
- lease price – $349/mo. vs. the 1997 EV1's $299/mo.
Can't argue with that, but the first of Tavares' enablers – which, I believe, presumes much lower future battery costs – is a big "if." A major component of Nissan's optimistic EV business plan, of course, is widespread availability of public charging stations, at least some of which will be 50 kW DC Fast Chargers, which Nissan says can replenish the Leaf's pack from zero to 80 percent SOC in a half-hour. The idea is to extend the useful range to much more than its nominal 100 miles when owners can make relatively brief recharging stops along their way. But DC fast chargers are expensive (compared to 240V Level II units), and so are unlikely to be all that plentiful, at least for a while. And what if you plan your trip around one, then arrive to find it inoperative or that you're third in line?We believe zero-emissions products will be successful if three key enablers drive the transformation: advancement of battery technology, advancement in the vehicle IT system, and build-out of the charging infrastructure network. We expect 80 percent of charging to happen at home overnight, but we recognize that a robust public charging infrastructure must exist to solidify EVs' longer-term standing in the mass market.... We already have visibility of more than 13,000 public charging stations ... nationwide by 2012 – and we expect this number to grow significantly by the end of the decade – approaching equivalency with the 115,000 gas stations available today.
Tavares also emphasized one very important EV selling point over ICEs and even hybrids: cost of ownership. Beyond the much lower cost per mile of electricity vs. gasoline, there's the very real advantage of virtually no maintenance: no oil changes, no belt or valve adjustments, no muffler replacements, etc. Tavares said:
On our morning drive in Franklin, we saw 78 miles of range remaining after 16 miles on mostly country roads in normal mode. Then we switched to "Eco" and drove back to Nissan HQ. Total miles driven were 30.9, and remaining range was 66 miles. And, as I've said before, we loved the range gauge's capability to instantly adjust to changes in mode and accessory load.Over the vehicle's life cycle, the cost advantage grows thanks to the benefit of lower maintenance costs due to less mechanical complexity. Over three years of ownership, we estimate a Nissan Leaf's maintenance to be approximately one-fourth the cost compared to a Toyota Prius.
In his pre-drive presentation, product planning director Mark Perry called the oft-quoted range anxiety concern: "a falsehood. If you have enough information," he said, "there's no anxiety." That's why the Leaf's range gauge is so quickly responsive, why there's an Energy Consumption Monitor (the "hyper-miler screen") and why the nav screen can show remaining range as a "reachable area" radius with public charge stations highlighted on it. Perry also said that bringing down the cost of DC fast chargers is a key element of Nissan's long-term strategy.
I also had recent opportunities for short spins in a Smart Fortwo ED and a Mitsubishi i-MiEV. Both drove pretty much as expected. In other words, they drove like electrically-powered versions of small conventional vehicles. EV conversion is probably the best use for the tiny two-seat Smart Fortwo, which is not much good at anything other than taking up just half a parking space. It had two big dials for SOC and electrical draw to or from the 18.5 kWh (Tesla-derived) li-ion pack, but no gauge for range – easily the most important piece of information in any EV. It did have a docking station for an iPhone from which, the engineer said, range could be derived.
The slightly larger, far more practical i-MiEV (a right-hand-drive Japanese model) looked like a conventional (low-buck) car inside, with a graphic SOC meter replacing the ICE's fuel gauge, but no range gauge. Its 16.5 kWh Li-ion pack can be drawn down to five percent SOC. I'll wait for longer drives in both before hazarding more comprehensive impressions.
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Award-winning automotive writer Gary Witzenburg has been writing about automobiles, auto people and the auto industry for 21 years. A former auto engineer, race driver and advanced technology vehicle development manager, his work has appeared in a wide variety of national magazines including The Robb Report, Playboy, Popular Mechanics, Car and Driver, Road & Track, Motor Trend, Autoweek and Automobile Quarterly and has authored eight automotive books. He is currently contributing regularly to Kelley Blue Book (www.kbb.com),AutoMedia.com, Ward's Auto World and Motor Trend's Truck Trend and is a North American Car and Truck of the Year juror.
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