A Heated Commute

I took the challenge by fellow pioneer Tom Moloughney (#250) to try and drive my 90 mile commute while using the heater (previously I made the drive comfortably, albeit on the cold side).

I’m happy to report that I completed the task yesterday:

- 85 miles total* (not my usual 90 mile commute, I had to go into NYC – enjoyed a heated garage during the day)

- Used the heat 5 times (2 on the way in, 3 on the way out) for approx. 6-8 minutes each time

- Heat was in the middle dial, fan was set at 2 (also middle dial)

- I made it home with 2% on the SOC meter (State of Charge)

- Battery temperature never got below 55°

- Ambient air temp was between 24° – 38°

In the summer and spring I was regularly making 90 miles, showing 8-15% SOC at the end of the day. So the results here show that heater use does have a significant tax on the batteries (~10% with fairly conservative use).

Knowledge is Power

When the temperature drops, so does the power capacity of a battery. Anybody who has left a cell phone or ipod in their car on a freezing night knows this, and all of us MINI E drivers who hail from the colder climes have seen this in the reduced charge-o-meter readings we’ve been seeing.

But as I talked about in my last post, I’m starting to think that the 15-20% hit in the battery capacity that many of us have seen has more to do with the algorithm used to calculate the remaining charge, and the temperature of the batteries, than with an actual loss of capacity due to cold temperatures. And a test I ran last week seems to back this up.

First, here’s the theory - as long as the High Voltage battery pack temperature doesn’t fall below 40°, then I don’t think the battery looses much capacity, if any.

To put this to the test, I decided to pioneer-up last week and follow my warm-weather routine – which is to not plug in #217 after my usual 45-mile morning commute. In the past this would mean I’d show about 52% battery left when I parked in the AM, 60% showing when I’d start my evening commute home, and  anywhere from  5-15% of battery range left when I pulled in at home.  If my theory held water, I’d be fine – though running very low on battery power when I returned home 92 miles later. If however the 15-20% “cold deficit” was in fact accurate, then I’d be sitting on the side of I-287 waiting for a tow truck.

So last Wednesday morning I pulled into Morristown after a modest (no faster than 60mph) and heater-free trip, showing 48% of battery power left. The high that day was 38° , and by 4pm I was reading a 55% charge – but the battery never got colder than 42°.  I drove back home (again very conservatively, 65mph max), and also without the heater. The charge-o-meter showed 0% with about 8 miles to go, but as happened in the summer and fall I just kept going without a hiccup. After getting off the highway, the meter did the usual recalculation and I gained 5% more by the time I got home. The battery temp when I pulled in was 72°.

After 2 hours of sitting in an unheated but insulated garage, the meter read 11% charge, with the battery at a fairly cozy 68°. Which is right around what I was getting in the fall.

Ironically though, my ipod  - which was 50% full when I parked in the municipal garage in the morning and left behind in the car – did drain pretty quickly, and powered off about 10 minutes into my evening drive, even thought it’s powered by a Li-ion battery just like the MINI E. Sadly the iPod doesn’t tell me its battery temp, but I’m guessing that without insulation (as the MINI E has) it must have been around the mid-30°s.

So the conclusions that I draw are:

1) The magic number to stay above – battery temp wise – is 40°. Keep that temperature, and at most you’ll be shorted 5% of the battery.

2) The Charge-O-Meter needs a new calibration, so that we don’t any get unnecessary range anxiety.

Knowledge really is power – about 15-20% more power when you’re driving an electric car in the winter!

A Cold Mirage?

Brrrrrr. There’s no doubt about it – when the thermometer dips, so does the range on my MINI E’s high-voltage batteries. And it’s been a hot topic of conversation among the MINI E pioneers in the northeast for over a month now that the weather has been so cold.

Most drivers are reporting anywhere from a 15-20% hit on the range displayed. And that’s in line with what I’m seeing as well – at least for a couple of hours. After that, I’m seeing some evidence that this “cold tax” is just a temporary reaction, and that those missing electrons aren’t really “gone”, just in hibernation (excuse the wordplay fun on all things cold…I can’t help myself).

During the summer and fall, my 45 mile morning commute would generally leave me showing 52% or so on my charge meter as I parked my car. I’d then plug in using the 110-volt cable, work all day (wink) and come back to a 75% charge at night, which meant I was getting between 2-3% recharge per hour.

Now I sometimes pull in to my parking space in the morning showing just 35% left on the meter. But when I come back in the evening – with the batteries still exposed to the same frigid temperatures – I still am greeted with a 72% meter. So either my recharging capability has more than doubled, or those extra 10-15 percentage points were really there all the time – just not being seen by the meter.

Charge accuracy, you may recall from earlier posts, is a pretty fuzzy thing, at least with this model of electric car. The algorithm tasked with calculating the charge isn’t yet smart enough to be more than a general gauge of the state of charge. What is interesting however is that the settings seem to over-estimate the actual drain that the cold weather will have, anywhere between 15-20%.

Baby’s Got New Shoes

Woa, the holidays knocked me out!  But i’m back, and will be updating more frequently now that December is done.

The big news to report is that MINI has swapped out all of our tires for new snow tires – GoodYear Ultragrip 7 to be exact. I hear that, because they are run flats, they had to be special ordered from Germany. It had to have cost BMW/MINI a pretty penny, but clearly safety is a potential issue with such a relatively heavier vehicle on icy roads. I noticed that the dealer, who installed them, only inflated them to 38 psi (max is 51 psi) – the question is what this will do to my average mileage range. So far I’ve noticed about a 5% dip, but it’s only been a few days.

In other news, we’re going through a serious and prolonged cold front here (mornings are in the teens, high’s during the day don’t reach much past the mid-20’s) but there hasn’t been a huge decrease in the battery performance. I do regularly plug-in during the day (thanks again Morristown Parking Authority!) now, but that’s more so I can feel easy about running the heater, etc. – I did a test a few weeks ago and made it home fine with only a few less % points than the summer commute.

Lastly, I had to go on an all-fossil diet for the past 2 weeks because we were traveling out of the area. It’s good to be back!

My First Tow

Sorry for the long silence, but the past month has been a busy one – for the job, the family and the car! Since you’re not really interested in the first two, I’ll give a quick update on the last – where the biggest news over the past 3 weeks was my first tow.

As a MINI E pioneer I knew it wouldn’t be a question of “if” but “when” I’d have to get the car towed – the semi-surprise was “how”.

All along I assumed it would be because I ran out of electrons. But instead, there I was in early November with plenty of juice showing on my chargeometer – but with almost no get-up and go, and the old “Noticeably Reduced Motor Power” icon light up. And this time, none of my earlier tricks would make it go away.

So as I cooled my heels waiting for MINI Roadside Assistance to show up, I had time to reflect that one of the big disadvantages of an electric car is that it relies so heavily on modern technology. In the old days, even a non-handy guy like me could open up the hood and at least get a clear idea of what is wrong with the car (I once drove 10 miles to get home from college with a bandana tied around a break in some hose – and it worked!).  But here I was, having the same feeling I would get whenever a computer would crash on me – knowing that there was something wrong happening, but having no clue and no confidence that I could go in and figure out what it was.

It turns out that it was a “fault in the optical cable that communicates between the battery and vehicle control unit” – definitely not something a bandana could help out in any way.

The “good news” side of this technology coin is that the most common problems –  software glitches – will be easily repairable; possibly even via a roadside “software patch”. That wasn’t so in my case (took about a week to replace the optical cable) but, no doubt companies such as BMW will be able to refine and optimize production in such a way that scenes such as the above will be less common in the future.

Can’t You Smell That Smell?

With MINI E #217 in the shop for the past week (a “battery communication” fault) I’ve been driving a gas-powered loaner car, and I had déjà-vu moment with it that we all may be experiencing in the future.

To appreciate it, let’s head back to remember what life in the 70’s was like.

I grew up in a happy, leafy neighborhood where just about everyone shared the same experience: a house with a ¼ acre lot, a fridge with Peanut Butter, Jelly & Wonder Bread, a Mom & Dad who both worked, and at least one who smoked cigarettes.

That was our world, the only one we knew possible, and we weren’t inclined to question it much. We didn’t give any conscious thought to why our bread was bleached white, and we didn’t take any special notice of cigarette smoke.

I continued not to notice it when I grew up and worked in a bar, or sat in a cube at my first “real job”, surrounded by people working on the R.J. Reynolds account and smoking Camel cigarettes. I didn’t smoke, but it didn’t bother me that others did.

And then the bans on smoking came. And soon afterwards, when cigarette smoke was no longer common, I began to really notice it. Where once I was oblivious to it in an airless bar, I can now pick it up coming from the window of a car ahead of me on the turnpike. And I change lanes.

The déjà-vu I had the other day is identical to the above, only replace cigarette smoke with the smell of gasoline.

I’ve been driving an all-electric car since June, and I haven’t been to a gas station in months. But filling up the loaner car, I realized how little I missed the smell.  And where once I didn’t notice it, there I was rolling the window down in 40 degree weather trying to get rid of it as I pulled out of the station.

Where once I was only aware of the smell of gas while I was at the station, there I was at night putting my shoes out on the front porch hoping to air them out, and repeatedly washing my hands. My sensitivity to it has clearly shot way up.

I’m not suggesting we “outlaw gas fumes”, nor am I ignorant of the reality that gas offers a tremendously convenient way to power things like cars, boats, lawnmowers, etc. I’m just saying that once your reality no longer includes a weekly dose of gas fumes, you’ll be accustomed to it.

Just chuck this on the pile of reasons why for me, as soon as I am offered a reliable, cost-justified electric vehicle, I’m going to get it.

A Halloween Trick, and Treat

So there I was, on All Hallows Eve, driving back from the store to go set up for our annual Halloween Party, when all of a sudden – after nearly 7,500 miles of issue-free driving – my experimental MINI E pulled an electric muscle and I suddenly lost almost all of my power.

I was on Veteran’s Highway in Orangeburg, NY – very near my house – when the “Noticeably Reduced Motor Power” icon came on. This is a feature that is meant to kick in when you’re very low on battery, and is intended to give you enough juice so you can limp off a busy freeway or drive ahead to a safe location before all the power is exhausted.  The trouble was, I still had about 80% of my battery charge remaining, so there was no good reason for this…except, this being Halloween, maybe I was meant to be forced off the road so I could meet a nasty end at the hands of a frightening, bloodthirsty monster.

Me (left) and Jay on Halloween

Instead, I met Jay.

About a minute after pulling off the road, while I was looking under the hood for an unplugged wire or some other obvious reason for my situation, I heard a beep – and I couldn’t believe my eyes.

After months of driving a MINI E without seeing another one on the road, there was MINI E #365 pulling off to join me. I knew there was only one other E in all of Rockland County, NY, and that one was 15 minutes away in Suffern – while this meet-up occurred not even a mile from my house!

Out popped Jay – who lives in the next town to our south, Park Ridge, NJ. He and I spent a about 10 seconds looking at the engine (“Uh…I dunno”), and then a couple of minutes exchanging stories and admiration for the car. He hadn’t experienced any problems so far (though he hasn’t driven as many miles yet) and he too was enjoying the silence of the drive, the pep of the motor and beauty of no visits to the gas station.

#217 meet #365

I took another photo of #217 & #365 together on the side of the road before Jay took off again. Then, weighing my options to get home – either call the MINI Roadside Assistance crew or try and coax it up and over the last hill, then coast down to my house – I decided to give the engine one more try. I put the key in, pressed the start button and – like magic – the “Noticeably Reduced Motor Power” icon was gone.

I hightailed it home, laughing at my first MINI E trick and treat of the year.

A MINI E “Pony Express” Trip

Don Young, MINI E #364, took an amazing trip last week – traveling almost 700 miles over 4 days from his Shelter Island, NY home on the eastern end of Long Island to the Bethel Woods Center for the Arts in the Hudson Valley, and several other stops in-between. To get there and back, Don organized a “Power Support Team” to recharge his MINI E #364’s batteries every 70 miles or so with high-voltage pit stops.

Original Art by Lea Miller

But Don didn’t just stop with the idea to take a high-mileage round-trip, he made an event out of it. Dubbing his journey the “MINI E E*TOUR”, he had custom window wraps and car magnets created to advertise and celebrate both his tour and “Power Support Team”, and also created his own t-shirts to give out to the many people he’d meet along the way. He also contacted a local newspaper in Bethel and did an interview there; plus he took the time to meet with strangers and bartenders (and probably some strange bartenders too) to show off the car and relate his experiences driving it.

I just love these kind of individual, people-powered quests, and my wife and I were very proud to support Don and fill him up on some solar-generated electrons last Thursday and Sunday. Infected by his enthusiasm for the project, my teenage daughter and I put together a poster to welcome Don and mark his journey to our home. Creating the poster gave us a chance to talk about things… like how weird it was that we were going to welcome a “complete stranger” to our home while most of us were away so he could plug his car in; about how normally we wouldn’t do such a thing; about how it was OK this time because we were all part of a broader community of people involved in the same thing – so while Don may or may not be strange , he was driving a MINI E just like us, for all the same reasons and with all the same desires for a better future, and that disqualified him as a stranger.

As Don himself noted, “On my MINI E E*Tour, I’ve had great experiences with 8 MINI E’ers, 2 companies, 3 corporations, and 1 foundation. I also learned that stopping once in a while to make new friends, and talking to bystanders about GP? (#364), is as nice a way to travel as I can imagine.”

At the risk of sounding corny or melodramatic, I imagine his experience was very similar to the old Pony Express system – Don too set out on the road in full awareness that his journey would only be complete if a group of people he’d never before met came together to help him. He too had to rely on faith in an unmet community. And in this day and age – where we rightly teach our children to be wary of strangers, and where we rely on standardized systems for everything from dining to refueling – what a unique experience that is.

In the few short years ahead, at just about the time my daughter will learn how to drive, electric cars will no longer be the domain of a few hundred pioneers. The frontier of “limited range” will be closed with the solutions of public recharging at the old ‘gas’ stations, battery swap technology, electrified liquid, or some other kind of innovation which will be hugely convenient and enable our modern and mobile lifestyles – but which will also be a bittersweet signal that this particular kind of unique, individual, community travel experience is unnecessary.

Don’s promised to post photos and tales of his experience, and I’ll be sure to link to them here.

The New Glossary of My Daily Commute

As part of the MINI E program, we get weekly emails containing driving suggestions and bits of insight from MINI on life in the prototype electric car lane. This week’s edition contained this handy little glossary and a tip on efficiently using the heater that I found interesting (who, for example, knew that a gallon of gas = 36.5 kWh!):

V: Volt; from the 17th century Italian physicist, Alessandro Volta.

In simplified terms, voltage is like electrical pressure. If an electrical wire were a water hose, the pressure or force of the water exiting the hose would be akin to the voltage level in a wire.

A: Ampere (Amp); from the 17th century French physicist, Andre-Marie Ampere.
Using the same water hose analogy, the Ampere is a measure of current flow. The volume of water which can flow through a hose is related to how wide the hose is – narrow hose, low volume, wide hose, high volume. Larger wires are able to carry a greater amount of current than smaller ones, and this current is measured in Amps.

kW•h or kWh: kilowatt hour
Those of you who are in tune with your electric utility bill are probably familiar with the kW•h because it is the unit measure by which you are charged for your energy consumption. A Watt-hour is the total energy used over time. Some of you have calculated your energy costs to drive the MINI E by using your kW•h rate to determine cost per mile. Your kW•h costs can vary based on such factors as where you live, when you charge and what your total monthly consumption is. A single gallon of gasoline contains approximately 36.5 kW•h of energy.

HV: High Voltage
There are two electrical systems we interact with on the MINI E. The low voltage system covers the 12V (Volt) components which are common to other MINI models. The power windows, windshield wipers, and map lights are examples of low voltage items. High voltage items are what sets the MINI E apart and typically runs in the range of 390V. The HV system is what propels the car, and provides heat and air conditioning.

SOC: State Of Charge
The amount of energy stored in the MINI E HV batteries, displayed as a percentage.

PEU: Power Electronics Unit
The magic gold box under the bonnet of the MINI E. It is the “brain” of the HV system and coordinates a variety of parameters such as power delivery and charging.

Module: High Voltage Battery Module
The HV battery in the MINI E is comprised of modules, each of which contain 106 cells. There are 48 modules in total which are individually monitored. Using a modular battery configuration enables more efficient packaging. If necessary, servicing the HV battery can be accomplished by replacing only modules which need to be, instead of the entire battery pack.

OUC: Occasional Use Cable
The 110V, or 12A cable which many of you keep with your MINI E, is commonly referred to as an OUC.

TIP OF THE WEEK

Heater Efficiency
This one works a lot like Goldilocks. Getting the warmest air from the cabin heater is achieved by setting the fan speed to the second setting. The lowest setting won’t take full advantage of the output of the heating element. The highest setting will blow so much air past the heater that it won’t have time to pick up all the heat. The middle setting is just right.

Hmmmmm – the closer we get to winter, the more I get nervous about this heater and it’s impact on my ability to get home….

Uh-Oh, It’s Getting Cold

Yesterday a big cold front hit the northeast, plunging temperatures into the 30’s for the first time since I began running on electrons, and it looks like it’s put a big chill on my driving range.

First off, let me say that it’s still early days as far as MINI E #217 and cold weather performance go, so there’s a good chance that all I need is a few more runs to figure things out, and the symptoms that I experienced yesterday won’t be an issue. And least that’s what the optimistic pioneer in me is hoping for. Now, here’s what put the “uh” next to my “oh” yesterday.

I had to take a day-trip to Atlanta, and so I drove 34 miles to Newark Airport in the morning, with the air temp at a relative balmy 50 degrees and my charge-o-meter reading 60% as I locked up in daily parking. Now my daily experience has been that, when I am parked, the charge-o-meter would actually gain 5-10% as the batteries relax and the remaining power consolidates. So I flew off to Atlanta, comfortable in thinking that for my drive home I should have about 70% or so. But this day the weather got colder and wetter (with snow flurries dusting the area), and so by the time I returned at midnight I still had only 60% showing. Not as much as I expected, but still plenty of juice to carry me 34 miles back home.

When I first started my trip back, things looked normal – loosing about 1% charge per mile. Then about 5 minutes into my drive I noticed my charge level started dropping much faster. With 20 miles to go, I’d lost almost 30%, so I turned the heater off (a decision not without regret as it was 38 degrees outside).  At about the halfway point, I was down to 15% – which is when I turned off the radio off, leaving me alone in the cold and dark with no human contact.

With 10 miles to go, I was under 8%, and resorted to turning my windshield wipers on and off manually (I have no idea how I even thought of that, but a desperate mind is a creative mind). At 5 miles from home, I hit 0% – and I was making mental preparation to feel the “reduced performance” kick-in, limiting me to 40 mph on the Garden State Parkway so I could crawl off the ride and freeze to death in the breakdown lane. The small part of me that was still warm was looking forward to the Roadside Assistance call, but the uncomfortably-cold majority of me was still searching for other ingenious power-saving manoeuvres like the windshield wipers. Remember that scene in Chitty Chitty Bang Bang where they are throwing items overboard to maintain altitude? That’s where I was.

Luckily, I nursed it up to Exit 172 which, as previous readers will note, is the top of a 1/4-mile long downhill with loads of regen opportunity. That, along with the back-road speeds of around 40mph (for some reason at 40mph it feels like it could go forever), meant that I arrived home ok. But I still only had 2% charge when I shut down in the garage, whereas in warmer weather I’d gain 10% coming off the highway. That means I lost 30+ miles of range, and the temperature only hovered around freezing.

So here’s the surprise – I always knew that the winter was going to present range problems with running the heater because it takes so much juice to create resistance in the heating coil (some estimates are that the car will lose 14-15% range for each hour of heater use); but the cold also clearly impacts the battery pack’s ability to hold a charge. To get an idea of this, leave a phone or an iPod in a car on a frigid day with a full charge, and you’ll return to find it seriously depleted after a few hours.

So this winter is going to present a double-whammy of sorts — a limited ability to run the heater and, if yesterday’s experience is typical – anywhere from a 20-30% loss of range from the batteries. So starting with today’s commute, I’m going old-school — driving gloves and a big winter coat and hat.