posted on January 24, 2013 21:00
2012 Nissan Leaf: Test Drive
By Khiem Dinh
Khiem Dinh is an engineer for Honeywell Turbo Technologies at the time of this writing. All statements and opinions expressed by Khiem Dinh are solely those of Khiem Dinh and not reflective of Honeywell Turbo Technologies.
I was back home in Florida for the holidays and my dad had a Nissan Leaf sitting in the garage. Being the engineering dork that I am, I had to give this thing a quick spin around the block as soon as I saw it. I wasn’t really sure what to expect. Would it be like driving a slow golf cart? Or would it be more like the electric go-karts used at K1 Speed? Well, there was only one way to find out.
|Before taking it out for a spin, you have to unplug the thing. This is the 'power port' I guess you could call it. The plug is the Star Trek phaser looking thing plugged in on the right. The port on the left side is for charging with the big daddy 480V charger. On the underside of the cover panel is the CAUTION sticker. I didn't bother to read it.
|Here are the two plugs covered and uncovered. Nissan, if you're listening, it would be nice to have a little LED light or something here so you can see the ports in the dark. Anyway, so why would you want the auxiliary port on the left? Well, its primary purpose is for the 480V Level 3 charger. However, from what my dad tells me, some peeps in Japan will charge the car at night using power from the grid and then run their house off of the car's battery pack during the day. Why? Because electricity is cheaper at night than during the day; so they effectively give the big middle finger to the power companies by gaming the system. If you live in a region where hurricanes are common, such as my home state of Florida, having a big ole energy storage station sitting in your garage can come in handy.
Thursday, January 24, 2013 9:14 PM
Cool review. When these first came to the US, I kept thinking what if...
Then I realized my apartment complex has zero power outlets near my space (over 75' away). I wonder how many other people who rent such as I just "can't" buy these.
Friday, January 25, 2013 1:50 AM
Nice article! I never drove the Leaf but compared to the Mitsubishi i-MIEV which is pretty basic the Leaf is a proper car. Electric vehicles can become a big thing if the gas prices keep climbing, at least for your daily-driving duties. Also they are helpful in storing excess solar or wind energy that would go to waste since it can`t be stored anywhere else.
I hope they get more affordable pretty soon!
Friday, January 25, 2013 4:33 AM
So, is there any possibility of tuning on of these? Not as a project car but in the real world. Your common stuff like brakes and suspension wouldn't be too hard but I would love to see if someone could ramp up the power on one of these things. Maybe install a larger electric motor(s) or significantly change the ECU maps to make one of these really crank.
Friday, January 25, 2013 5:54 AM
I heard a different reason for the headlight design. Due to the quiet nature of the powertrain, the wind noise around the side mirrors seemed excessive in an otherwise whisper-quiet environment, so the headlights were designed to direct air away from the mirrors. Of course, the design could be multifunctional.
Friday, January 25, 2013 6:28 AM
Is that kWh rating based on input from the wall, or output from the battery? If it's input from the wall, that's an amazing $0.027 per mile in "fuel" costs. Project Hypermiler, which is one of the cheapest per mile vehicles you can reasonably drive without killing yourself, is $0.076 per mile in fuel costs (at $3.79/gallon).
Even with the meter reading from the battery and a pessimistic 50% loss between the wall and the motor, that's still $0.054 per mile.
Of course, eventually the government will stop turning a blind eye to the lack of fuel tax collected for electric vehicles and the numbers won't pan out quite as well, but then again charge efficiency will most likely go up as well.
Oh yeah, the Achilles Heel of all e-cars: I can drive 700 miles on a "charge"... :)
Friday, January 25, 2013 6:39 AM
@ sethulrich: that's the reason I heard for the odd headlights as well.
Friday, January 25, 2013 6:57 AM
@sethulrich, that definitely sounds like a reasonable explanation for the headlight design. The car is extremely quiet. Mirrors are a high drag item too, so directing air away from them probably helps too with drag.
@protodad, electric cars basically seem like full size R/C cars I use to mess around with back in the day. A motor swap won't be easy, but if someone can hack the ecu, tuning the throttle tables should be easy. I'm sure there are built-in safety limits in the tuning for the motor such as the top speed limit. But if people are willing to exceed those to get more performance... I would actually like the full regen of the ECO mode all the time with the normal setting throttle response. I believe the Tesla S has full regen when you get off the throttle. The Mini Cooper E is that way.
Friday, January 25, 2013 7:11 AM
Springs, dampers, sway bars, and sticky tires might make that thing fun at autocrosses.
Friday, January 25, 2013 7:32 AM
@dusty duster, That was my first thought , as well. Except you would need a boom box duct taped to the roof blaring Al Green/ horrible mariachi/ Megadeth to make sure the corner workers knew you were coming :-D
Friday, January 25, 2013 7:36 AM
Man, so if you could fine some serious low speed autocross this thing could be a boss.
Friday, January 25, 2013 8:11 AM
Random tidbit - The power companies in Japan don't seem to mind if you run your house off of battery power during the day. In some areas they encourage it, especially during the summer months.
Friday, January 25, 2013 9:38 AM
@Boxed Fox, that makes sense. Here in LA when it's hot, we get the rolling brown outs, building power shutdowns, etc because the power draw on the grid is too large during the day when everyone is running A/C.
So the options are: shift some manufacturing to night time, have buildings shut off non-essentials (my office building will kill the lights and the A/C), build more power plants (not easy), find alternative power (I think solar is a GREAT idea in this regard, decentralizing the power grid, make a bazillion mini power plants). Of course solar works best during the day when the grid is strained the most. Anyways, that's another topic.
Friday, January 25, 2013 10:15 AM
Id like to see a residential electricity bill after one month of charging this thing, and then compare it to the cost of running a gasoline engine car the exact same duty. Im thinking gasoline wins.
Friday, January 25, 2013 11:27 AM
@ bigdave: see above, I did the math already. Leaf is cheaper per mile than my Jetta TDI, which is already one of the cheapest per mile vehicles you can get.
Friday, January 25, 2013 12:30 PM
@bigdave, not even close. I did the real-world calculation of 128mpg equivalent (forgot which page). Of course, that's in a mostly city setting with my dad driving (i.e. slowly). The EPA rates the Leaf at 99mpg equivalent which is more realistic. The best gasoline cars are hybrids and they are only at 50mpg. So the Leaf gets double the mpg of the better hybrids on the market.
Also factor this in: no oil changes. If you're really good about using the regen for braking, you have virtually no brake pad wear which reduces running costs even more.
Friday, January 25, 2013 7:14 PM
Any speculation on cost and frequency of something like battery replacements would be? Or motor rebuilds?
I would like to see the 5 year cost of ownership vs a CRX or something.
Saturday, January 26, 2013 2:10 PM
@ xXx: Nothing's going to beat a CRX in cost per mile, but then again a CRX is a tiny, spartan vehicle you can buy for peanuts.
Nissan expects the Leaf battery to last 10+ years before necessary replacement. However, that depends a lot on charge cycles and depletion levels. Batteries don't last as long the more you deplete them. I believe the battery failsafes at 50% to prevent rapid damage, but you'll get a lot more life out of a battery that you only discharge to 70-80% than 50-60%. Unfortunately, this reduces the effectiveness of the buy-in premium over a similarly capable vehicle like a Versa.
Then again, if you're buying a Leaf, you didn't buy it just because it was cheap per mile.
Saturday, January 26, 2013 4:08 PM
I see. I think the Leaf is also going to be much more comfortable than a stock CRX, due to the time gap alone, but I thought about that after I posed the question :)
A friend of mine has Solar City in Los Angeles for power, and is locked into something lie a $150-200 a month deal for like 15 years. He has a large family, so he was on the most expensive power tier rate and it saves him a lot of money even in a short 5 year span. I bet the Leaf or a car like it would be nice to have in that situation, because I don't think he would ever be "paying" to charge it. He already uses more power than he pays for.
Saturday, January 26, 2013 5:43 PM
Yep, solar + Leaf in the SW definitely helps. I'll just let the guinea pigs work all the bugs out and be a late adopter... :)
Sunday, January 27, 2013 12:47 AM
I`m not an electrical-engineer but there are lots to consider when you try tuning a Leaf like the resistance of the electric components and the heat they produce once you increase the amps to get a more responsive motor or peak-current when switching the motor on. Since the components seem to be specific built for the Leaf rather than a multi-use system like LS-series engine I think the headroom for tuning is almost zero. I guess it`s all about wait and see.
It`s also interesting to see that the Leaf has a pretty low aero-drag without using the classic drop-shape design that is used on cars like the Prius or Insight.
Sunday, January 27, 2013 11:23 AM
Just to note, the charge port on the left side is the Japanese CHAdeMO connection. It is the DC fast change port that unique from the SAE J1772 on the right. The SAEJ1772 combo charge is just finishing up development and will be deployed in the US. It will not require two different charge ports.
Also, the Nissan Leaf has an air cooled battery, not water. The coolant lines and tank in the front cool the power electronics such as the inverter which was the valve cover looking part in the "engine" bay. The battery air cooling is a point of contention with Nissan as many Leaf owners in extremely hot weather climates have seen excessive battery degradation.
Sunday, January 27, 2013 4:53 PM
More motor info: http://c.ymcdn.com/sites/www.electricauto.org/resource/resmgr/media/nissan_leaf_sae_2_11.pdf I wish I understood motors better. Our ASME section recently toured EV West, the shop that made the first converted EV car to race at Pike's Peak. Their big issue is heat - they can keep pumping current through the motor and make huge amounts of power, but only until the motor gets too warm. It's funny looking into their 'engine' bay and seeing huge cone air filters - but they're needed just as much as on a IC car. EV west generally uses DC motors for their lower upfront cost. EV West tour photos: https://picasaweb.google.com/103730272851707372536/Evwesttourfa12Keith?noredirect=1
Leaf suspension review: http://www.edmunds.com/car-reviews/track-tests/2011-nissan-leaf-suspension-walkaround.html Not the best start, but I'd guess some rims, springs and dampers could be tuned to make things more fun.
I think the biggest thing you're missing is the quite performance of electric cars. You can go full throttle without drawing attention. You can launch the car off the line and nail the throttle out of corners without the ire of other drivers. My ICE at redline draws more looks that I want. Stealth is key!
Drive a lot and you'll quickly use enough electricity to bump yourself into the next 'tier' of electrical pricing. In San Diego tier 1 is something like 14c/kWh, teir 2 is about 16c/kWh and tiers 3 and 4 are 27 and 29 c/kWh. The deadly tier 3 and 4 pricing occurs after the first ~400kWh sold per month. Either 1) don't use much electricity (like live where you dont' need AC) or 2) pay more per kWh but install an extra dedicated line for the vehicle that is billed seperately or 3) install enough solar panels to knock your usage back to just the cheap tier 1 and 2 usage. Solar may not be cost effective competing at 14c/KWh but it certainly will be at 30c/kWh. My favorite way to get clear pricing information on solar (no installation shown): http://www.solar-electric.com/grtiesyexqu.html (2/3 cost in panels, 1/3 cost in inverters and other hardware)
Sunday, January 27, 2013 5:27 PM
Southern California Edison will install your vehicle charger on a dedicated meter, so that charging your car will not bump your house service into a different rate tier. The need for that also depends on your household usage and typical charging time. Many smart meters are now being installed which offer different rates depending on time of day, so charging off peak (at night) is a reduced rate.
Uberthin is correct that electric motor performance is a lot of heat management. However, there is a lot involved in motor selection in the first place. A longer stack (longer length motor) will get you more power per mm increase versus a larger diameter. For instances, if you tear down a hybrid such as the Prius you will see that the drive motor is longer than the generator motor. A pure EV, like the Leaf with one electric motor, doesn't have as much packaging constraint. That can be an interesting trade off in packaging. Rotor design and stator design also have many many variables in design to select from in order to achieve particular performance parameters. Then there are motor controls, which is a huge topic in itself and not one I can even really disclose much on!
Monday, January 28, 2013 12:53 PM
Check this out. There is a Nismo Leaf.
Monday, January 28, 2013 1:12 PM
And now they're ~$19k after rebates (in CA):
Monday, January 28, 2013 1:45 PM
So the noise I just heard was screams from all the early adopters in the used car market for the Leaf? I checked autotrader for used Leaf's in my area and the cheapest one offered is $19,000. These cars start making a whole lot more sense at $19,000 .vs $35,000. That $16,000 difference pays for a LOT of fuel.
Monday, January 28, 2013 5:56 PM
Well, as with early adopters of everything, like the iPhone. $600 to start, $300 a few months later.
I would highly consider it if the range were 120 miles. But a realistic/relatively stress-free range of 70 miles doesn't work for me as going to visit family is about 90 miles round-trip.
Monday, January 28, 2013 6:38 PM
Yep. $19k makes sense if you're looking for a new car, and don't drive more than 70 miles a day.