Tampilkan postingan dengan label Efficiency. Tampilkan semua postingan
Tampilkan postingan dengan label Efficiency. Tampilkan semua postingan

Kamis, 02 Oktober 2014

Nissan LEAF Owner Reviews the i3 After 3-Day Extended Test Drive

I have always maintained that a good number of i3 buyers will be Chevy Volt and Nissan LEAF owners that have just finished up the three year lease on their vehicle. Phil Tipper is an EV "early adopter" and leased a Nissan LEAF. His lease will expire next spring so he's trying to decide which plug in vehicle he'll get next. The i3 is on his list of possibilities and when BMW recently offered the i3 extended test drive Phil  jumped on the opportunity to get to know the car a little more. I love this extended test drive offering from BMW. I think it's a great way to give prospective customers a chance to absorb what the i3 is all about. Phil is already an experienced electric car driver so he could focus more on the specific features of the i3, but many others who have never experienced electric drive will find the extended time they have with an i3 intoxicating. Having more than a few minutes during a quick test drive at a dealership will absolutely help convince people that may have been on the fence. It's simple, the more you drive electric the more you like it. That extra time behind the wheel may be all they need to make the decision to go electric for the first time. Phil wrote of his experience and thoughts on his time with the i3 and posted it to his blog. I thought is was interesting to hear what a Nissan LEAF driver thought of the i3 so I asked him if I could post it here and he obliged. Below is the post from Phil's personal blog:

As regular readers of my blog know, I'm actively researching the next electric car to replace our 2013 Nissan LEAF SL when its two year lease expires next June, and that the BMW i3 is on the top of my list of contenders.

I like the BMW because of its light weight for an EV (because of the carbon fiber structure of its "life module"), giving it the potential for good energy efficiency and promising good handling around corners, because it has a relatively powerful and torquey motor making it quick off the line, because BMW has tuned in tight steering and minimal body roll, because it is a rear wheel drive design (for classic sports car handling), because I like BMWs and I like the personal service that a premium brand provides, and because I can get a model with a range extender that offers a total of about 150 miles of range, with more range available with a fill-up of a tiny bit of gasoline. I like the idea that a range extender will let us take trips as far as Santa Barbara and San Diego without worrying as much about the reliability of public charging and the time recharging would take.


I'm also fascinated by the concept that having a range extender as a cushion will actually let us, paradoxically, drive more electric miles because we'll be more likely to take the EV than to fall back on the Prius, and because we'll be comfortable dipping deep into the battery's charge because the range extender will be there as a cushion and we won't risk needing a charge to get home.

On brief test drives of the i3, I had been able to briefly sample the car's quick acceleration and tight steering, but I'd had trouble getting used to the strong regeneration when the accelerator pedal is released, and I had even felt a bit of vertigo, especially as a passenger when the car was driven vigorously. So I had some concerns to resolve. On Facebook and in person, drivers of the i3 had told me that these concerns would resolve themselves quickly after I had gotten more used to driving the car. A longer test drive was needed.

To my delight, some BMW dealers recently began offering three-day test drives of the i3. This was exactly what I wanted. I found a dealer within 25 miles of my home that was offering the long test drives, Shelly BMW in Buena Park, California, and I found their internet team responsive and easy to work with. I thank them and applaud their willingness to take on the bother and expense of offering this program. To me, the BMW i3 is a car that benefits from a longer test drive so that the customer can learn its unusual.driving dynamics. In fact, I think that brief test drives around the block can be misleading, mostly because of the strong regeneration. I picked up a base model "Mega" i3 with the range extender engine and the optional 20 inch wheels and tires last Thursday morning.
Here are some of the comments about my experiences that I posted on the BMW i3 Facebook group.
Random impressions from first 24 hours, 150 miles:
Regen braking:


It's pretty much a non-issue and I beg to retract all of my earlier doubtful and even downright negative comments about it. It is different, but it is manageable and you adjust fairly quickly. I would still like to have the regen strength adjustable for a more relaxed driving experience in certain situations. At low speeds with this car, you WILL brake significantly if you need to lift your foot to readjust its position on the accelerator, and it would be very nice to be able to reduce the regen power if you just want to relax and coast with your foot off the pedal for a few seconds. Also, as many have said, the regen strength is lower at high speeds, so you don't go into full-on braking at freeway speeds if you lift off. My wife's first test drive comes in a day or so, and I expect her to have issues learning to drive the car smoothly, and I also expect uncontrollable giggling at some point during her test drive (from her, not from me). But I was able to drive her on a day trip today without her feeling too jerked about. And that was in both Comfort and EcoPro modes.

Ride and handling:


The car does bounce around a bit more than I like on uneven pavement in situations when I want a smooth ride, especially when I have a passenger. When I'm out for sporty driving by myself, the ride is tight and just fine for me. I put a lot of this down to the short wheelbase that allows the car to bob over bumps, and the 20 inch wheels with low profile tires. I had mentioned getting just a touch motion sick on short test drives before, but I have to say that I really haven't felt that in my first full day of driving the car. I imagine that having a chance for my inner ear and brain to get used to the car has something to do with that. I'll just say that the car is less relaxing to cruise in than my Leaf is because the steering is very responsive to any turning input and I find that I have to pay more attention to where the car is in the lane than I do with the Leaf. Some would say that's the price you pay for responsive steering. Fair enough.

Sporty driving:

Oh hell yes! You owners know this, but I think that the best kept public secret about the i3 is that there is a little sports car demon hiding inside this little thing. When I'm driving alone on a twisty, hilly road, it feels as good as any sports car I've driven (remember that I'm in the Mazda, Nissan, 3-Series class, not the Ferrari, Porsche class). The skinny tires grip on curves like the devil and the torque of the motor just goes on and on. Very, very grin-inducing, and very BMW. For me, this is the one and only reason for ME to get this car. Frankly, a fully optioned Leaf SL or a Mercedes B Class EV would do as good or better job for family cruising duty. They are more spacious and more relaxing to cruise around in. But in my experience, the i3 is more fun to fling around than a Tesla Model S because of its small size, light weight and tight handling. And I've driven a Model S on some of the same twisty roads. Given that I'm limited on parking space and we can't really have more than two cars, my EV has to be my fun car as well as being practical. Since the FUN potential of the i3 is so high, I can probably live with the practical downsides of the car.

Performance on Rex:

I haven't had much time driving the car in REx mode, but I purposely ran the battery down so that the car would go into Rex. There is a slight, almost unnoticeable vibration in the cabin, and you can hear the two cylinder motor chugging a little back there with the windows up. I drove the car fast up a pretty steep hill with the REx running and there was no reduction in power that I could detect. I must say that I do like having the REx there as a cushion. I've been driving EVs for over three years and I know how to handle range issues, but it was very nice to see a 40 mile cushion on the dashboard as we finished our 70 mile trip today (Note: The gas tank was less than 3/4 full).
Driving efficiency:

If the mi/kWh onboard readouts are to be believed, I'm getting no better efficiency in the i3 than I do with similar driving in my 2013 Leaf SL. I expected something like 20% better efficiency in the i3, but as near as I can tell, Nope! (Note: see my revised comment on efficiency near the end of the article.) You might say that I must be pushing the i3 harder, but after a day of cruising with my spouse aboard, I got around 4.2 mi/kWh, which is what I'd expect from my (heavier) Leaf in the same kind or driving. This was a mix of suburban and freeway driving, in a mix of EcoPro and Comfort mode. Go figure.

Random minor observations:
I like having frameless windows on the front doors. Getting in and out of the car is a pleasure when I don't have to contort to get around the upper door frame.

I like the placement of the 12v power plug for a phone charger. My phone sits down there in that well with the charger plug and I don't have wires everywhere.

The door pockets are spacious and handy for carrying all kinds of small items.

Installing kiddie seats in the back seats was a bit challenging. We have two grandkids, a four year-old and an infant. I had to remove the rear seat headrest so that the bigger kid seat would fit properly down into place. The base for the infant seat takes up a surprisingly large amount of space front-to-rear, so when we put in the actual carrier cradle into the base, the front seat will have to be moved forward a lot. Since I'm long-legged and tallish, we'll have to put the infant base behind the passenger and have her move her seat forward, and we'll have the bigger kiddo sit behind me, the driver, and she and I will have to negotiate over leg room.

Finally (after first 24 hours): No electronic or mechanical gremlins, errors, CELs, nothing. Very reassuring.

And here is my summary of my experience after the end of the three day test drive:

I'll summarize by saying that I liked the car very much, and that most of my concerns were eliminated after a few days driving it.

Positives:


+ The strong regen is a non-issue. It took a long test drive like this to convince me, but I no longer see this as a problem. Even my wife found it manageable. (BUT I do have to mention that she did have a second of unintended acceleration when she wanted to use the brake and forgot that her foot was still on the e-pedal. This was after only ten minutes driving the car for the first time, and we're sure that with more familiarity, this wouldn't be a problem.)

+ The quick acceleration and tight handling were really rewarding and these would be the biggest reasons that I'd choose an i3 over any of the competitive cars. This is really a little sports car disguised as an economical city car, and it's the true standout, as far as I'm concerned, for sportiest small four-door EV. (I know that the Spark is pretty quick, but it's really a tiny little thing and wouldn't work for us as a family hauler.)

+ Material and build quality were very good, even in the base Mega model. I happen to find the interior materials interesting and even the compressed Kenaf panels are fine with me.

+ I liked the maneuverability and tight turning circle.

+ I happen to like the car's unusual styling.

+ We were able to install kiddie seats for our two grandkids and reassure ourselves that the car would work for kid transport duty. This included one rear-facing infant seat and one front-facing kid seat. Space wasn't plentiful. The infant seat base takes up a lot of horizontal (front-rear) space, so it limits how far back a front passenger can move their seat. So we put the infant seat base behind the front passenger so that as the driver, I can get my needed leg space.


Features that I found only so-so:

* Having no keyless entry on the base car is cheesy, especially since the car has keyless-go.

* No option for power seats. That really should be an option for those who want it, with full disclosure that it adds weight and might harm range.

* I still find the seating position too high, and I kept wanting to lower the seat below the lowest setting. Ditto the steering wheel. It feels too high even at its lowest, and the high steering wheel position gives me a kink in my right upper shoulder.

* Loud and uncomfortable wind buffeting with the windows down above about 55 mph. I like to drive with the windows down, and without rear windows to open (or a sunroof) the "air hammer" that happens with the windows down is severe. I found that raising both windows to within about 4 inches of closed helps a lot.

* There was an annoying "reciprocating" thrum that I heard/felt at moderate to low speeds. I was never sure whether it was tire noise or drivetrain noise, or both, but it wasn't a typical EV driveline low howl that changes pitch as you slow to a stop. It was more
of a cyclical thrum that got slower in its cycle as I slowed down. Is this typical for the i3, is it unusual, or could it have been specific to the 20 inch tires? (Update: Tom Moloughney, our i3 online guru, told me that he had confirmed this sound in his own i3 to be coming from the 20 inch tires.)
* The short wheelbase (five inches shorter than a LEAF's) makes the car rock and bob over road imperfections. It's tolerable but it sure isn't a serene riding car. For most of my personal driving, it's no problem at all, but for times when I want to treat my passengers to a smooth ride, it's intrusive.

* I won't get into complaints about the crippled USA REx implementation, but the EV range that I got with the car was an unimpressive 72-ish miles. That's fine for most of my driving, but I'm used to getting about 85 miles with my Leaf, so this felt a bit limited. I do like having the cushion of the REx, though, and I think it would let me drive more EV miles, because I'd choose to take the i3 more often when planned trip lengths are a bit long, and a total range of about 150 miles with the range extender is very attractive after driving a Leaf for three years. It will make the difference between being able to use the car fully and not being able to in the spread-out LA metro area.

* Energy economy was poorer than in my Leaf on the freeway, but better than the Leaf on suburban streets, including with spirited driving. I find this rather disappointing because if I get an i3 REx, I'd like to do more regional driving trips with it, and I was hoping for better freeway economy. OTOH, with the good economy at lower speeds, I can drive it around like a hooligan without any misgivings (free energy from our home's solar roof).
- The "coach" doors. Awkward to move kiddie seats in and out of the back seats unless you have plenty of space on the side of the car. We had to back the i3 out of the garage into the driveway to have enough space to swap the kiddie seats in and out. The maneuver also required removing one rear head rest because it interfered with the upper part of the forward-facing child seat, and this requires partially folding that rear seat forward to be able to remove the head rest. We found that it was also necessary to slide the front seats forward and flip the back rests forward so that we had enough room to get to the child seat restraints and belts.

We wind up needing to swap out the child seats a couple times a week because we have two cars and only one pair of child seats. So this will become a frequent exercise. Not a huge deal, but if it's raining (if it ever does around here again), I'd be either doing this drill in the rain in the driveway, or back the Prius out in the rain to be able to get the i3 doors fully open and move the kid seats in and out. First world problems, to be sure.

- The placement of the charge access door on the right rear fender. I was lucky that I chose a 25 foot cable when I bought my Aerovironment L2 EVSE. Since I mounted the EVSE near the left front fender of a headed-in car, my choices with the i3 are to back the car into the garage or to wrap the cord around the car to get the plug to the i3 charge port. The latter choice was the more appealing one to me, and it worked fine, aided by the i3's short overall length.

* And of course, I find the car's price and value for money proposition disappointing. I'm going to want a good sized discount AND a boost to the residual percentage to feel okay about the lease pricing. We'll see how things are next Spring, when I'm in the market. But BMW really needs to kick in the whole $7,500 Fed rebate, or price the car to make up for the difference. OCF (Owner's Choice with Flex - a purchase program with a guaranteed buy-back at the end of the term) programs are less attractive in California because you're charged sales tax on the car's full cost, even though you're only using it for a portion of its life. Leasing would be more attractive to me, but not at BMW's current pricing, rebate amount and residuals.

Lastly, the only issue or problem I had in three days and 265 miles was a problem with " low cost charging". Even though I had set the car in that mode, it insisted on charging immediately. This was with Level 2 charging with about 15% SOC remaining.

And by the way, my existing Aerovironment Level 2 home EVSE with Nissan badging worked great with the i3.

Selasa, 02 September 2014

The Norby's "Driving to Net Zero Energy Challenge" Starts off Strong!

My i3 is powered by electricity generated by my home solar array. EV+PV is really a fantastic combination and one that I believe will be fairly common in the near future.  So how can you possibly top that? How about by getting two i3s and powering both of them plus your entire household's energy use by your  solar array! That's exactly what the Norby's are attempting to do.
I have frequently written on my blogs how one of the best part of being in BMW's e-mobility test program for the past five years has been meeting and interacting with many of the other people in the program. Together we learned how to live with the issues that test cars frequently have, we built up our own support network and we simultaneously realized how fantastic driving electric was. It was a really a great experience and one that was nothing short of life changing for many of us. 

While I've literally made hundreds of acquaintances in the program, there are a few people who I've really connected with and now consider friends, and one of them is Peder Norby. Peder and his wife Julie live in Carlsbad, California and went from MINI-E to ActiveE to BMW i3, just like I did, only they went one step further and got two i3s! Like me, the Norby's power their electric cars with clean energy from their rooftop solar array. However even though our systems are about the same size, their array provides about 1/3 more energy than mine does because of the location (sunny Southern California) and orientation of the arrays. 

This year, Peder and Julie began a year-long net-zero energy challenge. They are attempting to live the entire year with their solar array providing all the energy they need to power their home and both of their cars. I believe this is a fantastic story and a glimpse into what the future has in store. Peder has been updating the progress on his i3 blog but now that he is one quarter of the way through the year, I asked him for permission to post his progress here and he happily agreed.  Below is a little introduction to what the Norby's are doing followed by the three month update. 

It’s hard to get this down to a sentence or two, but when we built our home in 2005,  our ethos was to partner with nature, harvesting the gifts of nature, building the most efficient home possible.

In doing this, we wanted to elevate, we refused to compromise or lower the enjoyment of our life and the caliber of our dwelling, we refused to reduce our life to living in a small cave with one solitary light bulb, solely for the sake of efficiency.

Our desire was to express ourselves artistically, with the highest quality materials, design and comfort in the size home needed to accommodate our family and friends, while partnering with nature, being as efficient as possible. We wanted to live in a net zero energy home, harvesting food and drink from our land. Not big or small, not right or wrong,  just our home.

The idea is a simple one: Harvest sunshine from the roof of your home to provide 100% of the power needed for your home and the two cars in the garage. That is our goal in this "Driving to Net Zero Challenge.
 
The 12 month documented journey began May 15, 2014. Three months in, things are looking pretty good:

Update Month Three. We're killing it!

The idea is a simple one, harvest endless sunshine from a small portion of a roof to provide 100% of the energy needed to power a home and two cars with zero utility cost, and zero gasoline cost.

Summary:
  • 1/4 of the way through the year,  -167 kWh and a $468 credit.
  • Stats, Stats, Graphs, Graphs. 
  • We're killing it! Ready to make a projection!
  • Our French import.
We estimate that we will be -$800 by Oct/Nov
Solar PV production holding steady at 1326 kWh

Electricity use for the two BMW i3's rose to 478 kWh for the month
We have a credit of $315 for the first seven months of the year

1/4 of the way into our "Driving to Net Zero Energy" challenge and as they say in political election coverage:
"I am ready to make a projection and call this race"
We will be below zero in utility cost and gasoline cost providing the energy for our home and guest house, and the two cars in the garage driven a total of 24,000 miles a year.  In fact we are so far ahead we will accomplish this goal four months earlier than planed with the January 2015 true-up bill from our utility. 
Our natural gas cost for a year is $301.27
We estimate at the true-up bill that we will have a credit of $400 to $450 for our electrical use and a cost of natural gas of $301 for the year thus  -$100 to -$150 in total energy cost for the year.

How about total cost?

As I mentioned in my first post in May, an asterisk is required regarding the cost of energy as our utility does not let us carry over our electricity credit to our natural gas cost.  Essentially our valuable peak hour electricity that we do not consume will be a gift to our utility.  As the years go by we will most likely convert one or two of the natural gas appliances at the end of their useful life to electric in order to reduce the natural gas bill by using our excess electricity credit.

Where are we with energy usage and gasoline cost now compared to 2007 when we began this path to energy independence?

In 2007 our energy cost were:

$3,800 a year in electricity
$   300 a year in natural gas
$2,800 a year for Julie's Infinity G35 gasoline
$2,400 a year for my Volvo S60R gasoline

Total:    $9300 a year in energy cost.  ($792 per month)

This is not far off the statistical norm for a US family which uses an average of 11,000 kWh per year ($3,060 at SDG&E rates) and $2912 for gasoline according to the 2012 EPA statistics.
In 2014 our energy cost are:

$      0 a year in electricity*
$  300 a year in natural gas
$      0 a year in fuel cost for Julie's BMW i3
$      0 a year in fuel cost for my BMW i3
Total $300 a year in energy cost. ($25 per month) 
* we donate $450 worth of electricity back to SDG&E.

You can see how quickly that $9000 a year in energy cost savings will pay off a $30K Solar PV system, $15k in extra construction cost for a thick well insulated home, efficient appliances and led lights and $1000 for a EV charging station in the garage.  We have calculated from the installation in January of 2007 we reached the payoff point in April of 2012.

From April 2012 and for the next few decades, we will have essentially zero or de minimus cost for energy saving us $200k to 300K in energy cost with escalating utility and gasoline cost.

How about total usage?

Julie and I live normal lives, things come up and situations change. The interesting part of our Drive To Net Zero Energy challenge is that we are real people with a real life and not some demonstration house with nobody living in it.

We have been doing really great using a net total of -167 kWh of electricity (generation vs consumption) for the first three months of the challenge. We can extrapolate the prior four months of usage pre i'3s, assuming we had the efficient BMW i3's and the extra 1kw of solar pv production which would have saved us 225 kWh per month. We estimate that by May of next year we will be very close to a net of 0 total kWh used, +- 250 kWh per year which is a normal usage and weather variable.

The French Import.

I bet you thought it was a car :)

Julie and I have decided to make an impact on two young adults lives.  We are hosting through Rotary Youth Exchange, a 17 year old French student named Peroline for a one year exchange. By doing so, an American young man is traveling to France to begin his year as an exchange student in France living with Peroline's family.

Our household has now risen to four and the extra electricity that our 17 year old exchange student will use will most likely push us into the positive use territory.

Hosting a 17 year old young lady French exchange student for a year was not contemplated and is not a very good idea for the Drive To Net Zero Energy Challenge!

But life is life, unpredictable, wonderful and real.  We are very happy to have Peroline as part of our family for the next year and we're looking forward to driving her everywhere, using lots of electrons, to see the sights of our great nation.

Our goal remains Net Zero Energy usage as well as Net Zero Energy cost.
We'll see how the the next 3/4 of the year goes.

Imagine a better future and your participation in it.

Next Month:

  • Charging stations and what's on the horizon.
  • Our CHG emissions 
  • Our version of GHG offsets
Thanks for reading and commenting.

(Past "Driving To Net Zero" articles on Peder's blog)

Energy Challenge Introductory Article

Bonus video:
Below is one part of a series of videos that Peder and I participated in. The video series is called "Wherever You Want to Go" and was produced by BMW back in 2011. BMW recruited Buzz Aldrin, Marissa Meyer, Robin Chase, Syd Mead, and many others to participate and Peder, Todd Crook and I were also chosen to because of our high level of participation in BMW's e-mobility program. The four-part series is available online and did a good job of opening the up a conversation about where we are going with regards to personal mobility. Take a look and see if you can spot Peder and me.  :)
 

Kamis, 21 Agustus 2014

BMW i3 REx vs Chevy Volt: My Take

The Challenge

Last week I was contacted by High Gear Media Senior Editor, John Voelcker and asked if I had interest in doing a head to head comparison piece between my i3 REx and a Chevy Volt. Green Car Reports contributor David Noland (who happens to own a Volt and a Model S) wanted to pit the Volt against an i3 REx and asked John to reach out to me and find out if I was up for it.

I liked the idea of swapping cars and driving side by side for a few hours and that met David's needs as well. David wanted to do an efficiency test and measure the miles per kWh's used driving 15 to 20 miles in a city environment, and then do the same thing at highway speeds of 65 to 75mph. Going in, David expected the i3 to be more efficient in the city driving test, but the Volt to be more efficient on the highway test where weight plays a lesser role and aerodynamics are more important. The i3 is tall, has a large front area and is a bit boxy compared to the Volt. This creates a much higher CdA which will lower the i3's efficiency at high speeds. Having driven my i3 for a while now, I knew it would be more efficient in the city cycle, but I figured it would probably tie the Volt on the highway leg of the test. My i3's life time efficiency so far is 4.5 miles per kWh and I do at least 50% of my driving at highway speeds.
David averaged 4.1 miles per kWh over a 46 mile drive at highway speeds. This was driving about 15 miles in charge depleting mode and another 31 miles with the range extender running.  The display only shows an average speed of 56.7mph, but much of the trip was done at 70+ mph
David was also very interested to find out how the range extender performed. In my opinion, the i3's range extender is largely misunderstood. Even months after the launch, few people really understand how it works, what it can and cannot do. It has been called everything from a "limp mode" to an "emergency use only" option, and quite honestly BMW hasn't done itself any favors by not fully explaining how it works and how to use it properly. I promised David he could drive it as he wished, and even purposefully overwhelm the REx by driving fast enough to use more energy than the range extender could produce, should he desire to do so. At one point he even asked if I minded if he did just that, but due to the other traffic we couldn't really sustain a speed much over 70mph for long and we were not going up and long, steep inclines so the REx was able to put out enough power to maintain the SOC between about 4% and 6%. In short, we couldn't overwhelm it without driving in a an unsafe manner.
Getting ready to take off from Nauna's Bella Casa in Montclair

There aren't many long climbs in my area and I've driven with the range extender on quite a bit. I haven't found any condition where it isn't perfectly capable of allowing me to drive as long as I needed to, including hundreds of miles if I really wanted. However I know the REx has its limits, unlike the Volt. I have heard stories of people not being able to maintain highway speeds as the car drops to 45 mph suddenly. That's a problem that BMW needs to address. I think they need to make a better effort to communicate to the customers what the limits are, and I also believe the customer needs to be cognizant of the limits and keep an eye on the SOC under high speed driving up long inclines. It's not a do-all-under-any-condition vehicle. The range extender has limits but I definitely believe that for the vast majority of people it will do just about anything they need. Also, since the i3's electric range is double that of the Volt, the range extender will be used much less, so it's reasonable to understand why it is less robust.

People are surprised when they see the i3 next to other EVs. It is larger than I believe many people think it is.
On the Road
 
I felt very comfortable behind the wheel of the Volt as I've driven many of them and have always liked the driving experience that they offer. However, this was the first time I've driven a Volt since getting my i3 REx three months and about 6,500 miles ago. The two cars definitely feel very different. The much heavier Volt absorbs road irregularities better and is quieter at high speeds, where the boxy i3 has noticeable wind noise. The i3 is much quicker, especially at higher speeds and has better braking and handling. The i3's steering is more direct and sensitive and the Volt's brakes seemed a little spongy or squishy compared to what I'm used to in the i3. The i3 is clearly more of a performance car, while the Volt offers a more supple, softer ride. The regenerative braking on the i3 is much stronger than the Volt's, even in Sport mode and low driving gear. I'm sure I would adjust to it if I had a Volt for awhile, but I just couldn't get myself to stop for traffic lights without needing to depress the friction brake pedal every time. I almost never use the friction brake pedal on my i3 unless it's an emergency situation where I need to slow down unexpectedly. I really love this on the i3, and haven't found any other EV to have a regen system that matches it. It's definitely one thing that BMW got right. I know the Volt blends regen with friction braking so I suspect most of the time I depressed the brake pedal I wasn't even using the friction brakes, but I've really grown fond of the one-pedal driving of my i3 that anything else now seems sub-standard.
The interior of the Volt
The interior of the i3









I found both cars comparable in seating comfort and room, with the Volt having a larger cargo area. Because the e-drive motor and range extender are under the deck behind the rear seats, the i3's cargo deck is higher, which cuts down on the cargo space, but it also doesn't have a tailgate lip so you can slide objects in and out without having to pick them up over the lip to remove them as is the case with the Volt, which my bad back appreciates. Personally I like the uncluttered, modern interior look of the i3 better, and the large center display probably is the nicest I've seen in any car besides the Model S. However the exterior styling of the i3 is definitely unconventional and I'm sure many people will say they like the look of the Volt better, but styling is subjective so I'm not really going to get too caught up appearance here. One thing I really do like in my i3 is how the absence of a center transmission tunnel (battery tunnel on the Volt) provides a much more open, spacious feel in the cockpit. In fact, this makes it quite easy to slide across from the drivers seat and exit from the passengers door if you want to.  
The Volt has a larger cargo capacity, but with the rear seats folded flat, the i3's cargo space is definitely adequate for my needs.
Efficiency

David really wanted to focus on the efficiency of the cars so we did roughly 15 miles of city driving, followed by 15 miles of highway driving at 60 -70 mph. There were a few occasions we got up to 75 or so to pass other vehicles but for the most part we drove in the middle lane and averaged a little under 70mph. In the city cycle the i3 averaged a 5 miles per kWh used compared to the Volts 4.5. The Volt did better than I expected in this part of the test though, which I am happy to report. On the highway test the i3 delivered  4 miles per kWh used and the Volt averaged 3.5 mi/kWh. David and I were both surprised that the i3 actually had a larger advantage on highway driving than it did in city driving, but was 14% on the highway. I suspect if we drove faster, and averaged over 70 mph, the Volt would have caught the i3 in efficiency. The test also isn't perfectly controlled, since David and I aren't the exact same drivers. However, we are both very experienced electric vehicle drivers, and understand perfectly well how to maximize efficiency with the use of regenerative braking and limiting jack-rabbit style take offs. We drove with the climate controls set to 72 degrees and the windows closed.

During the city driving test. I jumped out of the Volt at a red light to grab this picture.
Conclusions

Having had quite a bit of previous experience driving Volts, there were really no surprises for me. I have always liked the Volt, and nothing from this experience has changed that. It's a very capable extended range electric car that offers a good ride, decent performance and nice styling. It is a better choice for long range driving (over 200 miles) and definitely if you live in a mountainous area. I can't even count how many people I've recommended the Volt to; and many have stopped back to my restaurant weeks or months later to show me that they took my advice. With a starting price of $34,999 it's a really a great deal. The i3 REx on the other hand starts at $46,125 which is $11,000 more. Yes, you do get a more nicely optioned vehicle but it's very hard to ignore the $11,000 difference. If price is a big consideration then it's hard not to pocket the eleven grand and take home a Volt.

However buying a car isn't always a rational decision, and there are indeed emotions involved. If that weren't the case we'd all be driving $15,000 Honda Fits. There are a lot of reasons why the i3 REx is a better EV for me than the Volt. First off, I drive about 33,000 per year, and the 38 mile AER of the Volt would mean I'd be driving on gas about as much as I drove on electric. The i3 REx will allow me to drive on electric over 90% of the time. For me to increase that 100% I'd need to jump up to Model S-type range because the times I have needed the REx were usually 150 to 200 driving mile days and there are no other current production electric vehicles capable of doing that without using a robust DCQC network which doesn't yet exist in the Northast. Another consideration is the 3.3kW onboard charger that the Volt has. I'd find it very hard to buy any EV that was limited to 3.3kW charging. My i3 can actually charge faster from zero to full an a level 2 EVSE than a Volt can, yet it has twice the electric range. GM absolutely needs to upgrade the onboard charger to a minimum of 6.6kW for the next generation Volt in my opinion.

I've read many comments on various online forums regarding the size of the i3's gas tank and I can say I categorically disagree with the notion that the car needs a larger gas tank. In fact, I'd be fine with a smaller one. If you think you need a bigger gas tank on the i3, then what you really need is a Volt because you're buying it for a use that it's not really intended for. The i3 REx is fine for driving in range extender mode for short distances, and I think it's really a great car for trips up to 150 miles or so, but if you really need to frequently drive more than that, it just may not be the best fit. If you need to go further once a month or so, then sure that shouldn't be a problem as long as you don't mind the 2-3 minute stop to refill the tiny tank, but frequent long distance driving just isn't the car's best use.

I also put a big emphasis on the driving experience and the i3 is really a blast to drive. The Volt is fun in its own right, and it is certainly no slouch by any means, but the i3 is noticeably faster and has a much more direct steering feel. I also love the fact that the i3 is all carbon fiber reinforced plastic and aluminum, the open cockpit and simple dashboard with the large center display. It was indeed the better choice for me, but honestly, I would be very happy driving a Volt also, especially if I drove less than the 90 miles a day that I do now. I don't think you can lose with either of these extended range EVs. Just pick the one that fits your budget, needs and desires and you'll be happy with whichever you choose.

You can read David's thoughts on his Green Car Reports article here.

Selasa, 12 Agustus 2014

Guest Post: Efficiency or Range? You Can’t Have Both.

The i3 is the most efficient production car available today

Every now and then I have a reader send me an article they wrote and ask if I'd like to post it here. Usually it's not exactly what I'm looking for and politely explain why I won't be posting it and thank them for sending it nonetheless.  Occasionally I'll get something interesting though, like the post below which was sent to me by Robert Kasper. I think it's particularly timely since just last week I posted the Tesla/BMW comparison piece and I think this is an interesting follow up to it.  I hope you enjoy:                    

  Efficiency or Range?  You Can’t Have Both.

…But Advanced Technology Can Help.

By Rob Kasper

In the world of electric vehicles, whether Battery Electric Vehicles (BEVs) or Plug-in Hybrid Electric Vehicles (PHEVs), there is a clear trade off between range and efficiency.  For a given technology, efficiency suffers as range increases due to the weight of not only additional battery capacity, but the increased structure and volume to haul that capacity around.  Now that there are a significant number of plug-in vehicles being manufactured, and a recognized standard to test them, we can identify trends.  Consider Table 1 and Figure 1, a plot of efficiency (as measured in EPA MPGe) vs. range in miles for 2014 plug-in electric vehicles measured by the EPA.  They are grouped into Battery Electric Vehicles (BEVs) and Plug-in Hybrid Electric Vehicles, and further identified as either conventional or advanced technology design and construction.  Conventional technology is generally characterized by a manufacturer’s use of an existing gasoline powered platform modified for battery electric drive, steel frame construction and cladding, and standard battery technology.  Advanced technology is generally characterized by a clean sheet, purpose built EV design, extensive use of aluminum or aluminum plus Carbon Fiber Reinforced Plastic (CFRP) for weight savings, higher energy density lithium ion battery packs, with the bonus of performance equivalent to or exceeding the best of conventional technology plug-in vehicles.

Figure 1: Efficiency vs. Range

Table 1: EPA Electric Range and MPGe

Beyond the obvious observation that the price of greater range is lower efficiency within a given technology, it is important to note the significance of advancing technology.  The ground-up EV design, significantly lighter weight construction, and advanced battery technology of the BMW i3 and Tesla Model S push the blue trend line significantly up and to the right of conventional BEVs’ green trend line.  As significant is the single data point (in purple) representing the only advanced technology PHEV currently available – The BMW i3 REx.  Not only is it capable of greater efficiency and far more range than any conventional PHEV (the red trend line), it is more efficient than all but two conventional BEVs, with only slightly less range than all but the most inefficient conventional BEVs.

It is this outlier of a data point, the BMW i3 REx that might best help illustrate why a smart means of increasing the range of an EV may not necessarily be to add more battery capacity.   Battery energy is clean and well suited for powering vehicles for relatively short-range transportation but due to its weight and lengthy charge times, inefficient and inconvenient for long distances.   On the other hand, the benefits of energy density and convenience make gasoline/diesel energy better suited for longer range transportation with the trade-off being greater well to wheel emissions in many parts of the world.  In the case of the BMW i3 REx, each mile of range requires either 0.15 pounds of gasoline, or 5.7 pounds of battery capacity.  At 37 times the mass specific energy density of battery power, very little gasoline is required to extend range for a given tank size, and that tank can be replenished in minutes nearly anywhere in the well developed fossil fuel infrastructure that currently exists worldwide.  This capability requires a 265 pound increase in the weight3 of the vehicle for the REx engine and associated systems, which imposes a 6% decrease in efficiency, but once set, that efficiency does not appreciably decrease as more energy in the form of gasoline is added to increase range.  Increasing battery capacity cannot increase range as efficiently, as not only must the weight of the battery increase by 37 times the weight of gasoline per mile in the first increment, but by the weight of increased structure and volume, as well as even greater battery capacity to offset the reduction in efficiency resulting from the weight increase.  There comes a point where the sacrifice in efficiency may no longer be worth the additional range to be gained.
See figure 2:

Figure 2: EV Energy Storage (and Generation) Weight vs Range for Advanced Technology EVs



1- EPA testing protocol does not account for approximately 4 miles of range remaining after REx fuel exhaustion when publishing a 72 mile battery powered electric range before REx activation, but does account for it in the total range calculation of 150 miles:  72 electric miles + 1.9 gal x 39 mpg + 4 electric miles = 150 EPA range (76 electric + 74 gasoline).  76 miles of range is also the result of dividing the EPA measured total i3 wall to wheel consumption of 22.0 kWh by the i3 REx EPA measured consumption rate of 0.288 kWh/mile.  This value is further corroborated by the CARB BEVx designation awarded to the i3 REx which requires the electric range not only be at least 75 miles, but that it must exceed the gasoline range, neither of which would be possible without accounting for the ~4 miles of range remaining after REx fuel exhaustion.

2- The EPA’s 95 MPGe rating of the Toyota Prius Plug-In Hybrid includes 0.2 gallons of gasoline operation plus 29 kWh of electric operation per 100 miles.  Subtracting the 10 mile of gasoline operation contribution to the total (0.2 gal X 50 mpg) yields 29 kWh per 90 miles, or 32.2 kWh per 100 miles, which results in 105 MPGe for electric only operation. (MPGe = 33,705 divided by watt hours per mile.)

3- While EPA rated at 87 miles of range in its base form, purchasers of the Mercedes-Benz B-Class can choose to pay an additional $600 for the Range Package, which makes an additional 17 miles of range available.  There is no difference in total battery capacity between the two configurations, only the percentage of SOC made available to the driver.

4- The 8 BMW battery pack modules weigh 55 lbs. each, for a total of 440 lbs.  Reference page 17 of the BMW i3 Service Managers Workshop Participant Guide at http://darrenortiz.com/website_pdfs/BMWi3PG.pdf.

5- 265 lbs for the REx engine and all associated equipment is the difference in weight between the i3 BEV and i3 REx as published on BMW’s spec pages:  http://www.bmwusa.com/Standard/Content/Vehicles/2014/i3/BMWi3/Features_and_Specs/BMWi3Specifications.aspx
http://www.bmwusa.com/Standard/Content/Vehicles/2014/i3/BMWi3RangeExtender/Features_and_Specs/BMWi3RangeExtenderSpecifications.aspx.  Adding the 440 lb. battery weight makes the total energy production and storage weight at 76 mile of range 705 lbs.  This increases by 11.4 lbs. of gasoline for every 74 miles driven beyond 76.

6- Widely quoted in other sources, Car and Driver claims the Telsa Model S 85 kWh battery pack weighs 1323 lbs: http://www.caranddriver.com/reviews/2013-tesla-model-s-test-review.  This is exactly 600 kg, making it appear to be an estimate, but it is the only number we have to work with, as Tesla does not publish the spec.

7- Weight of the 60 kWh Tesla Model S battery pack is estimated from the 85 kWh figure to be 60/85 X 1323 lbs. = 934 lbs.

Kamis, 07 Agustus 2014

BMW & Tesla Taking Different Approaches But Will Ultimately Face Off


Horatiu Boeriu of BMWBLOG recently did a piece titled "BMW vs. Tesla - Which Company Is A Bigger Innovator?" in which he mentions that while both companies are competing in the premium automobile segment and are committed to electric mobility, they are taking different paths to achieve success.

I'm not going to try to analyze who has it right or who is a bigger innovator, but it's clear that both companies have chosen to focus on different aspects of their respective vehicles. With Tesla, it's all about the batteries. Unlike every other automobile manufacturer, BMW included, Tesla's approach isn't for their electric cars to complement their lineup of gasoline and diesel offerings since they don't have any. Instead, it is to render gasoline vehicles from their competitors obsolete. In order to do so, their cars have to be at least as good or better than most features of competing gas cars; and that includes range, performance and utility. BMW on the other hand doesn't need to necessarily worry about making everything better. They can focus on specific needs of certain customers and make a vehicle that is better than any other at a specific set of tasks, without cannibalizing sales of other vehicles in their lineup. If you accept that premise, it's not difficult to understand why we have the Model S and the BMW i3.
Tesla knew they had to knock it out of the park with their first high volume vehicle offering. They knew they had to offer a car that could stand its ground against all of the top luxury sedans while offering a range long enough to allow for road trips enabled by the Supercharger network. Even though that was an enormous task, and one that few automotive analysts really believed they would pull off, they did just that and the Model S is a smashing success. No disrespect to the sexy styling or the fabulous performance of Model S, but the heart and soul of what the car is can be attributed to the enormous battery pack it uses, filled with industry leading, high energy-density batteries. Tesla is all about the batteries. Even though the Model S uses batteries that have a higher energy density than any other EV manufacturer, they still aren't satisfied. They aren't waiting for the market to bring them better, cheaper cells for their future cars. Instead they are in the process of building what will be the first of many Gigafactories, which will be the largest lithium ion battery manufacturing plants in the world. This will drive down costs, guarantee that they have the supply that they need, and allow them to constantly upgrade to better cells without needing to wait for battery manufacturers to retool production facilities to produce them. The key to Tesla's success is having the best batteries available, and to manufacture them for less than what their competitors are paying for comparable cells. It's the only way to offer large battery, long range electric vehicles and be able to price them competitively.  It's Tesla's edge, and perhaps their only hope to compete and actually beat the large, established automakers.


BMW's not in the battery business and is unlikely to follow Tesla's path as such. As mentioned above, since they didn't need the i3 to do everything better than any other gas offering as the Model S had to, BMW could focus on a specific set of goals with their first electric vehicle. The i3's code name was the Megacity Vehicle and the goal was to develop a car that would be the perfect electric vehicle for the increasing populations within the megacities of the world. They also wanted this car to represent a departure from traditional manufacturing processes with an emphasis on sustainability.  They set out to make the most efficient production car available today and they achieved that goal. The extensive use of carbon fiber reinforced plastic and aluminum allowed BMW to shave 400 to 500 lbs off the car which played a primary role in its efficiency.

Will BMW leave Tesla in their rear view camera? That doesn't look very likely at present.
I believe the i3 is as much of a learning experience for BMW as it is their first electric vehicle. Every step of the manufacturing process was rethought and redesigned for the i3. In fact, the i3 uses 70% less water and 50% less electricity to manufacture than a comparable-sized conventional BMW would. In addition, the Leipzig manufacturing plant where the i3 is made is now completely powered by wind-generated energy. So as much as the i3 is an important vehicle to BMW today, the lessons learned bringing it to market today will pay dividends when future i cars are made. The i3 indeed paved the way for the rumored i5 and other models from the i brand. You can expect larger battery, longer range electric cars from BMW i in the not-so-distant future. I suspect by the time Tesla releases the Model III, BMW will have an electric offering which is comparable size, range and price, and that will be good news for the consumer.
My i3 had a visit by its big brother. I'm one of the few lucky people outside of some select journalists who have driven an i8 on public roads. The future is definitely looking electric!
BMW knows that by focusing on a specific set of needs (efficiency, performance, sustainability) rather than long range, the i3 isn't as well suited for road trips as the Model S. They knew that every kWh of battery that they added would sacrifice efficiency and increase the cost of the car. I still maintain that if BMW had indeed used a slightly larger battery and delivered a true 100-mile EV, it would have been much better received, but that's a pointless argument now. While it does have a shorter range, the i3 does have features that are not even available in the Model S, such as adaptive cruise control, collision avoidance with automatic braking and self parking. As you would expect from BMW, the i3 is an extremely fun car to drive, and a great addition to the current lineup of EV offerings. I think it fits in well situated directly between the Model S and the LEAF in price.
My i3 at home
BMW did realize some customers would want a longer range so they offered the range extender as an option. It's really a great option to have and while I personally like how well it works, it isn't for everybody. Many have argued that the REx ruins the purity of an EV, and while I can agree with that, I can't agree that it shouldn't be an option. If such a feature allows more people to buy a plug in car, then I think that's great. I see the range extender as a temporary fix until batteries get better, lighter and cheaper, but a necessary evil at present. Obviously BMW agrees with that and unlike Tesla, they will wait for the market to bring them improved battery tech while Tesla has decided to bring improved battery tech to the market. Different approaches, different cars and I don't think either is right or wrong. They are both working on bringing cutting edge technology to market today with the promise of even better things to come. BMW and Tesla aren't going head to head in the EV space right now, but they certainly will. Competition is good because it forces innovation. Maybe Horatiu was onto something after all.

One last point: If Nissan does deliver on the rumors that the next generation, 2016 LEAF will have a 150+ mile range, and they can deliver it for a reasonable price, then both Tesla and BMW should be concerned, very concerned...

BMW and Tesla going nose to nose in the premium electric vehicle market is inevitable.

Minggu, 27 Juli 2014

This City Car is at Home in the Country



If you listen to BMW marketing, they'll have you convinced that the only place to really experience the full benefits of the i3 is to drive it in a city environment. Pretty much every description they offer for the i3 includes how it's a car made for the Megacities of the world. Take this from the BMW i website for instance: "Electric and electrifying – the BMW i3 redefines mobililty(sic): with its visionary design and innovative BMW eDrive transmission it’s the sustainably designed vehicle for everyday urban use."

I'm definitely not saying the i3 isn't perfectly capable of negotiating the urban jungle on a daily basis. In fact, city driving is where the i3 is most efficient. Driving streetlight to streetlight, using the regenerative braking to recapture much of the energy used, since you rarely drive for long without needing to slow down, is the type of driving that will allow for better overall range.  Aside from this efficiency advantage and the fact that you usually don't need drive so far (making the limited range less of a concern) and perhaps the ease of parking the i3's tiny frame on city streets, there isn't any other advantage to driving it in the city. I've now been driving electric for over five years and have piled up about 150,000 electric miles on my MINI-E, ActiveE and i3. The crazy thing is, I live in a very rural part of New Jersey where cows and horses are part of everyday life and the bright lights of New York City are over 50 miles away. Like my previous EVs, my i3 has adjusted well to life in the country, even if this isn't the life BMW had envisioned for its carbon fiber halo car.
My MINI-E was a city country car too!

However I'm not satisfied just saying it can do fine in the country and suburbs. I believe it is indeed better suited for a life outside the city limits, so please allow me to defend that statement.

For starters, the vast majority of people who live in the suburbs and in rural areas live in private residences and the exact opposite is true for those who live in cities. Living in a private residence gives you control over your electrical supply and parking arrangements, which as you know is pretty important if you drive an electric car. You simply hang a 240v EVSE in your garage or carport and your refueling issues are mostly solved. The vast majority of electric vehicle charging occurs at home, and having the ability to install a home based EVSE where you live really simplifies things. Conversely if you live in an apartment or condo in the city, establishing a location to park and charge your car can be an enormous challenge. I have had dozens of people who live in New York City reach out to me through this blog asking for help in securing a charging location because they wanted to buy an EV. It's not impossible, but it requires a lot of work and in many cases a lot of money and persistence. Some parking garages have allowed customers to install a private EVSE and separate meter so they can pay for the electric it uses. This usually costs a couple thousand dollars and requires a lot of legwork. Other garages have allowed the person to plug into an existing 120v outlet and pay a small monthly fee for the energy which is the best solution if 120v charging will offer enough energy for the persons driving needs. In any case, it's a lot harder to recharge your car if you live in the city.

Then there is the driving experience. Of course the car drives the same in any environment, however I contend you simply cannot possibly enjoy the full benefits of an electric car while driving it in the city. I can still remember a few years ago when I was driving my MINI-E home from work one night. I own a restaurant so some nights I drive home late at night after closing and the roads by my house are desolate. This particular summer night I had the windows open and the radio was not turned up too loud. I remember hearing a squeaking sound and thinking there was a problem with the radio so I lowered it a bit but when I did the noise got louder. It was then that I realized the noise was crickets. The car was so quiet, I could hear crickets as I drove along at night as clearly as if they were sitting inside the car with me. I promptly turned the radio completely off and finished my drive home to the chorus of crickets. Five years later I still roll down the windows and turn off the radio on some summer nights, and allow the crickets to serenade me on my way home. It's about as peaceful and relaxing as anything I can imagine, and I arrive home calm, relaxed and ready for bed. Open the windows of your car in New York City at any time, day or night and you'll hear horns beeping, people yelling, sirens blaring and car engines racing. You simply cannot appreciate the quietness of an electric car in the city as much as you can in the country because there are so many other loud noises occurring constantly around you that are overwhelming your peaceful retreat to silence. In the country, crickets are about as loud as it gets.

Finally there's the energy savings. City dwellers don't drive much because everything is close so they won't realize the fuel savings as much as those who need to drive farther. I said above that I have driven 150,000 miles in the past five years with my EVs. If I had done that with a car that averaged 30 miles per gallon (which is much more efficient than the average car), I would have spent around $18,500 for gasoline. Instead my electric cars used only about $8,000 in electricity so I've pocketed about $10,500 in fuel savings. A typical person who lives in the city would have driven much less than I have and their energy savings would also be much less accordingly. In fact, most people I know who live in the city don't even own a car, as it is too expensive and just not necessary because of the extensive public transportation system.

So all that's left to discuss is the range. I suppose the main reason BMW and other manufacturers have pointed to EVs as being better suited for urban environments is because they have limited range and require longer refueling time than their internal combustion counterparts. This is a valid point and one that will prevent many people who live in rural areas where destinations tend to be farther apart from considering an EV. I'm certainly not saying that everybody today is ready to go electric or that the current electric offerings would suit the needs of everybody, but I do believe the vast majority of people could definitely integrate one into their life if they want to. The "if they wanted to" is the operative term here because going electric does require some degree of planning and range awareness. You can't just hop in the car and drive without knowing roughly how far you'll be going and the location of possible charge points just in case you need them. That is, unless you have an EV with an extraordinary range (ala Model S) or one with a range extender like my i3 REx has. By setting up charging stations in various locations along the routes that I frequently drive, I've effectively built out my own private network, but I understand the average person will not be willing or able to do that. Having the range extender there "just in case" has completely removed any concern about whether or not I can make any destination and offers that secondary level of support that many considering an electric vehicle are seeking. My previous electric cars were definitely fine for me and my life in the country. The range extender on the i3 only makes it that much better and will allow others in rural areas who may not have been as "adventurous" as I was to go electric. With long range pure EVs like the Tesla Model S and smaller battery, range-extended options like the i3 REx, the electric "Country Car" has definitely arrived.