Monday, December 7, 2015

SparkEV is quickest charging EV in the world

If I say SparkEV is the quickest charging EV in the world, you should ask "are you insane? What kind of ludicrous claim is that? Of course Tesla is the quickest!" And you'd be correct. But it'd be also correct to claim that SparkEV is quickest charging EV in the world going by percent of battery capacity charged.

When I first read this article, I thought "what a stupid record. It doesn't matter if it's 90%. What matters is how many miles". Given that Tesla Supercharger is 90kW to 120kW (or is it? see below), there's no question Tesla would be quickest charging in terms of miles added for a given duration of time.

But human psychology doesn't work that way. Humans typically try to maximize charging percent, at least to 80%, not just stop charging when there's enough miles to get home. One can see this effect at fast charge stations when you see people hanging around to squeeze out charge even when the car is charging at 2kW using 50kW charger.

Most of us don't have exposure to fast charging other EV. Manufacturers do not disclose this information. Automobile media for most parts don't even mention various types of charging, let alone benchmark charging speed. We just accept that what we get is what we get, and assume all EV behave like the EV we drive. In case of Leaf drivers, they would just accept that all EV charges at 12kW at 80% using 50kW charger. In my case, I assumed all EV charge at 45kW to 80%. I mean, it's called "fast charge" and it would make no sense to charge at anything less to 80% battery capacity, the recommended capacity for batteries.

Then I encountered how slowly Leaf was charging. Then I found out about Tesla taking almost an hour to charge at supercharger. Then I read the article above. It became clear that SparkEV is quickest charging EV in the world.

SparkEV charges faster than record breaking EV

Fast charging record the article above describe is the time it takes to reach 90%. It took 33:15 (0.554 hours) to charge 21 kWh. That works out to 37.9 kW on average. Considering that 24kWh Leaf drops to below 36kW even at 60%, the new 30kWh Leaf is significant improvement.

Since the test was performed in Europe, there is no SparkEV. But there are other fast charging EV, such as Kia Soul EV and BMW i3, even EV not available in US such as Renault Zoe. If 37.9kW average power to reach 90% battery capacity is the record, that means all the other EV that are available in Europe are slower than this. As far as I'm aware, SparkEV is the only fast charge capable EV that's not available in Europe at this time.

I timed a charge session from 12% to 89%. It took 20 minutes (1/3 hour) to add 13 kWh, average speed of 39kW. This is quicker than the new Leaf with 30kWh battery. Below is the screen shot of the charging session.

Note that this charging power started from 12%, not 0% like in Leaf's case. If one monitors SparkEV charging at DCFC, it stays at about 45kW when it's below 80%, and tapers to 9kW at 99%. While I don't know if it's linear taper, what's important is constant charging below 80%. That means starting at lower battery state will result in even higher average power.

Because SparkEV battery is only 19kWh vs new Leaf 30kWh, SparkEV would definitely win percent charged race even if the power is the same. With higher average charging power, SparkEV would be far quicker in percentage race.

SparkEV is the quickest charging EV in the world!

Tesla Supercharging could take an hour

By now, it should be clear that I poke my nose into other EV business as evidenced by my MPGe$ for various EV post and Love letter to Leaf post. I came across an interesting forum discussion about Tesla supercharging speed. They said Tesla takes almost an hour to charge using Supercharger. They said charging time is from Edmunds article, which I googled to mean this one.

I didn't see what model he used, but let's assume S70 with 70kWh battery. Further, let's assume 80% of battery capacity is usable. Then the full capacity is 56kWh. The plot in the article seems to show 90kW supercharger. He started charging at range of 40 miles, which is 17% of 240 miles.

56kWh * (100%-17%) = 46kWh
46kWh / 90kW = 0.51 hours = 30.7 minutes

If the car charged at full power, it should only take 30 minutes. Obviously, the car doesn't charge at full power all the time. But it should charge to 80% by then, right? I mean, SparkEV charges at full power (about 45kW) to 80%, Tesla has to be at least as good, right?

No. When it comes to charging to X %, SparkEV is far quicker than Tesla. Tesla charges at 90kW (or 120kW) only for short time. Then it slows down very (very very) quickly. But its starting power is higher. That's the good news for Tesla; it's charging speed is quicker than SparkEV for number of miles added per unit time due to higher starting power, despite the quick taper.

Eye-balling from the graph (red plot), it seems to show about 60kW on average, maybe 70kW to 80%. After 175 miles range (175/240 = 73%), it's slower than 50kW. After this point, SparkEV would be quicker. But "quicker" is kind of hollow; SparkEV would have about 70 miles range at this point (80%) while Tesla has 175 miles range.

Fortunately for Tesla, there aren't Superchargers next to SparkEV. But if there were, it might make for small dent in Tesla pride to see tiny SparkEV charge only for 20 minutes or less and drive away while they're waiting almost an hour (or more) to get charge. Human psychology is a funny thing.

SparkEV is still the quickest charging EV in the world, even quicker than Tesla!

Tesla Supercharging power

Even worse for Tesla pride might be their Supercharging power. Since I don't have Tesla, I have to go by the data from forum posts.!/page21

It seems Tesla taper is linear. For 120kW, it starts to taper almost immediately. For 90kW, it tapers starting at about 105 miles range (out of 250 miles = 42%). 80% would be 200 miles, which shows about 45kW power. Just at this moment, SparkEV would be charging just as fast as Tesla in adding electrons to the battery (ie, absolute sense, not in %) when both cars are at 80% battery capacity.

Because the slope for 120kW case is almost linear from 50 miles to 200 miles, one can estimate the best case average power by looking at the power at average of 50 miles and 200 miles (125 miles). That number is about 80kW. Since 90kW charger is slower, 80kW power is the best case scenario for Tesla to reach 80%.

Technically, Tesla does charge at 120kW, but only for short time. SparkEV charges at 45kW out of 50kW charger from 0% all the way to 80% battery capacity. In terms of charging power with respect to advertised charger power, SparkEV is 90% of peak power while Tesla is only 67%.

SparkEV is still the quickest charging EV in the world, even at utilizing fast charger capacity!

Slow Tesla supercharging on same circuit

Researching into Tesla super charging, I came across supercharger installations. Multiple Teslas can charge from superchargers on same circuit, but reduce power to each vehicle. While it's not clear how often this happens, and how the power is reduced, what seem to happen is that charging power could be significantly lower.

I'm just guessing here. Ideally/worst case, two EV on one circuit would reduce the charging power by half (45kW from 90kW charger), four EV on one circuit reduce the power by four (22.5kW from 90kW charger). But Tesla has very steep charge taper. Unless both Teslas with similar state of charge are plugged in at the same time, the balance of power may not be evenly split. Well, it wouldn't be if Tesla designed it like I would! But people who use supercharger would typically have low state of charge, so evenly split scenario might be more common. I mean, that's why they're there, right?

It's not clear if more than two sharing is allowed with same circuit superchargers. But if two Teslas with low state of charge are charging together using 90kW supercharger, the power delivered would be slightly less than SparkEV. If one considers some losses, SparkEV might be even quicker than Tesla to 80% (or even more?), not just in percentage race, but actual delivered electrons.

One might argue that current crop of CCS DCFC (made by ABB) does not allow multiple vehicle charging simultaneously, so the time taken by multiple vehicles should also consider waiting time for SparkEV. In fact, since one's locked out of charging while another is in progress, that's worse than Tesla charging where they can plug in and walk away. That is actually a very valid point. However, it's my blog, I'll tweak the parameter to favor SparkEV this time, unlike ev-ranking blog post where I tweaked the parameter to favor Tesla.

SparkEV could be even quicker than some shared circuit Tesla supercharging, not only in percentage race, but actual electrons delivered! This would make SparkEV the quickest charging EV in the world from all points of view.


For a cheap "compliance car" as some continue to insist, SparkEV is quickest charging EV in the world. For some situations, SparkEV is even quicker than the mighty Tesla supercharger with regard to amount of energy gained, not just percentage. Maybe one day, all EV will charge as quickly as SparkEV, the reigning king of fast charging.

As far as I know, no automobile publication or blog or other sources discuss and rank fast charging speed. This might be the historical first! Going forward, I hope publications include this benchmark. 0-60 time is so 20th century, battery range is so 1999. Benchmarks should include DCFC speed. Welcome to 21st century!

Edit 2015-12-15

One can guesstimate "instant" charging power by timing how long it takes to charge 0.01kWh (or more), because ABB charger does not give instantaneous power. SparkEV displays instantaneous charging power when it's "on" while charging. I did this long ago, and it showed about 45kW below 80%; it was fluctuating between 42kW and 48kW.

I was monitoring it again today, and it was fluctuating between 47kW and 48kW! I think this has more to do with charger and ambient temperature, although it had firmware update since the last time I was monitoring it. The screen shot was made when it had close to 80% as you can see from the "green goo" bar graph on the left that represents battery capacity.

Unfortunately, I got distracted and went way over 80% (Puppy is misspelled word for Poop Pee), and also forgot to take photos from ABB charger after charging was done, so I don't know what the average power was. But it shows SparkEV is capable of using 96% of charger power to 80% (48kW out of 50kW charger). I have to wonder how fast it would charge if there are chargers with more power.

And what do you know? Insideevs had an article on just this topic. It's about 30kWh Leaf setting new fast charging record using different charger in Europe.

From the comments, it seems the new charger is 120kW unit capable of two simultaneous DCFC. It's capable of 60kW as base model, higher power than 50kW ABB unit that's in CA today.

Leaf charged 21.04kWh in 0.4425 hours which is 47.5kW on average. Oddly, it showed that is 80% battery whereas previous record (37.9kW described above) was also 21.04kW but to 90%. If we assume the race to 80%, SparkEV would be close to or faster than new Leaf with bigger battery using the higher power charger, even when SparkEV is using the lower powered unit. I have to wonder how fast SparkEV would charge using the higher power charger.

Who wouldn't make such capable car that's probably quickest in the world available everywhere and talk about canceling it? Why, the dunces of GM, of course!

Edit 2015-12-16

% charged is important metric, because this is the amount of time one would spend at the charger. People don't charge to X miles when they've only charged to 30% battery, just enough to get home. People generally stick around to 80% or more, regardless of the miles. For the real-world charging scenarios, SparkEV wins this contest by far against all EV in the world.

Another important metric is miles added for given time (charged miles per hour), not the kilowatt that I focused on previously. For more miles added, one can take longer trips even if multiple DCFC sessions are required. As an extreme example, if SparkEV can add 300 miles in 20 minutes, it would be even quicker than Tesla in driving 500 miles; Tesla would need 2 DCFC seesions at 1 hour each (2 hours) whereas SparkEV would need 7 DCFC sessions (72 miles each), each lasting only 5 minutes (35 minutes total).

There are two ways to achieve higher miles added per time. One is to have higher average power in charging (aka, brute force). Another is to have more efficient vehicle (aka, elegant efficiency). Because SparkEV is more efficient than either the Leaf or Tesla, even lower charging power would benefit SparkEV in terms of adding miles per time. Table below shows the calculations. Before you jump on "your table is ludicrous for making SparkEV faster than Tesla", read the explanations below.

All figures are based on EPA MPGe except for the top entry which is based on mi/kWh that I measured for SparkEV for driving at constant 55 MPH and 93% DCFC efficiency (5 mi/kWh * 0.93 = 4.65 mi/kWh). I also use best case charging power I've seen using 50kW charger, which is 48kW; since we don't have higher power chargers in CA, this is probably low estimate for what SparkEV can do in terms of charging power. It's certainly within the realm of possibility even with 50kW charger.

For the rest (not the first row), I use EPA MPGe figures. For SparkEV, I explore the case of 48kW and typical case of 45kW, both figures actually observed with 50kW charger.

Since I don't have Tesla, I have to eye-ball the average charging power from the graphs above. I use 80kW average for 120kW supercharger, 70kW for high estimate of 90kW supercharger, and 60kW for low estimate of 90kW supercharger.

For Leaf, I use charging power figures from articles. Although 37.9kW was supposed to be to 90% using ABB charger, same energy in kWh was added as 80% case with evtec charger.

While it's not apples to apples, SparkEV comes out ahead of even Tesla in miles added per unit time in low estimate (60kW) for Tesla supercharger. This is not surprising since SparkEV would add about 70 miles in 20 minutes, about 200 miles in one hour. This is about the time Tesla driver spent at supercharger in Edmunds article mentioned above.

So even using almost apples to apples comparison, SparkEV does very well in miles added per time against Tesla, even better than low estimate for Tesla . But we have't seen the best of SparkEV, yet, due to lack of higher power chargers. It's certainly in Tesla's league at the moment, and with higher power charger, it could exceed 90kW Tesla supercharger in miles added per time.

Using real world efficiency of SparkEV compared to EPA MPGe, SparkEV is quickest charging EV in the world in every sense, even quicker than Tesla. Not apples to apples, I know, but it's not likely that I'll have Tesla any time soon for apples to apples comparison.

Sunday, November 15, 2015

SparkEV, you are NOT a compliance car

I didn't want to discuss this, because it was so obvious, but it seems some (many?) have mistaken notion that SparkEV is a compliance car. This post is to show some evidence that isn't the case.

Compliance 101

For those not aware, few states in US mandate few percent of total car sales must be zero emission vehicles (ZEV). They also create a market for it such that car companies that sell more ZEV than required can sell the excess sales figure as "ZEV credit". Some gasbags claim that Tesla is making out like bandit for selling ZEV credit than actually selling cars; if you can't see the flawed logic in this argument, please, read it over again. (hint: you must sell ZEV to get ZEV credit!)

There used to be one ZEV mandated state: CA. Then OR joined. Now supposedly there are several ZEV states operating as co-op where credit sold in those states can be applied to over all pool.

Definition of compliance car

As such, the definition of compliance car is simple. It's cars only sold in compliance states (CA and OR for now) only for the purpose of getting ZEV credit for them to sell more gas cars. The reason they don't sell outside of compliance states is due to cost. Even though the car maker can buy ZEV credit from their competitors (eg. Tesla), it does nothing for them while boosting the competitor's bottom line. Even if they're losing some money (or lots of money) by selling ZEV in compliance states, it'll at least bring the people into their dealers and keep the money out of their competitors' bottom line.

One famous compliance car is Fiat500e. Sergio (Fiat CEO) famously said that he hopes people don't buy the 500e, because the company loses $14,000 for every car sold. Whether this is reverse psychology is debatable. But the little Fiat is a down to a tee (cee?) example of a compliance car. Supposedly, the CEO had such disdain for BEV that much of the drive train of 500e were not made by Fiat, but contracted out to Bosche. As such, there's no hope of making money by selling another company's car, especially if that car must use biggest (and most expensive) available battery among mid level EV at the time.

You dirty compliance car!

Some consider compliance cars as a dirty word. They see them as taking away from "true" EV and helping the evil gas car maker that'll make even more CO2. It's like they have some religious aura about disliking compliance car outside of logic and reason.

The simple fact is, compliance cars are just as much EV that doesn't use imported oil. If the compliance car performs better and cost less than "true" EV, by all means, I whole heartedly recommend compliance cars. If they didn't offer this better and low cost EV, would consumers buy more expensive and crappier "true" EV or would they simply buy gas cars? Most would probably buy gas cars, making the situation (imported oil and CO2) far worse.

Compliance cars would be losing money for the car maker. If they made money, they'd have wider sales (see below why not always the case). If the evil car maker is only selling compliance BEV to be able to sell more gas cars, and their BEV is good / cheap, it's all the more reason to buy them. Buying their compliance EV and hurting them financially is a good thing if you happen to dislike the car maker.

Here's an example. Fiat 500e is pretty much the definition of compliance car. But if it came with DC fast charging and cost comparable to SparkEV ($26K, $7K less than current 500e price), it would be a great tiny car: 0-60 in bit over 8 seconds, almost 2 seconds quicker than Leaf, and it comes with 6.6kW L2 instead of SparkEV's 3.3kW. Personally, I like the taller head room of SparkEV, but for smaller people who like "cute" cars, it would've been the best EV. It'd even be a great choice for people who live in areas without much DCFC now (will be coming), but many L2. Compliance or not, such car would be a great buy.

SparkEV compliance test

SparkEV is sold in limited number of state, CA and OR in the beginning, also in MD as of third quarter of 2015. Hmm. Smells like compliance car.

Lesser known is that SparkEV was also sold in Canada to fleet customers from the beginning. Starting in 2016, SparkEV will be sold retail as well in Canada.

SparkEV also has been selling in South Korea since the beginning.

SparkEV is also sold in Mexico.

Just from the fact that SparkEV is sold in places outside of compliance states of US means SparkEV is NOT a compliance car.

SparkEV pricing

Mexico is an interesting link. The price in the web site in Mexican Peso converted to US dollar result in $24K while it's sold as $26K in US. If it's only for compliance to meet ZEV credit in certain US states, why would Chevy sell SparkEV in Mexico for even lower price than US and lose even more money? Are they insane? Or more insane than usual? hint: Iron Duke Camaro!

Most likely, Chevy probably isn't losing money by selling SparkEV, but making money. Otherwise, why offer for sale in places that do not mandate it? Based on Mexico price, they're probably making $2K to $3K per car in US. This could be more than 10% profit, a profit margin that even Carlos Ghosn, the legendary CEO of Nissan, would be proud of.

By the way, Carlos will be a historic figure, and all those who's shaken his hand or have some memorabilia from/about him is well advised to keep them safe; they will become valuable to your grand kids. No, I'm not suggesting that you cut off the hand that shook Carlos' hand, but don't wash it. Ever!

Even without knowing Mexico pricing, let's deduce how much SparkEV would cost. SparkEV is basically Spark gas version converted to EV. Much of the car's body and chassis is the same, adding only minor cost. Electric motor is made by GM, a derivative of  Chevy Volt motor. Then the gas engine swapped with electric motor is only minor cost difference, if any. Biggest addition is the battery. Assuming $300/kWh, 19kWh battery would cost $5700; let's round up to $6000.

Spark gas 1LT costs $15,000. Assuming 10% extra for swapping gas engine for electric motor and adding $6000 for battery,

$15,000 * 1.1 + $6000 = $22,500

Well, well, what do you know? It's $1500 less than MSRP in Mexico, and $3500 less than MSRP in US. Those are some healthy profits for Chevy!

Why not sell SparkEV throughout US and the world?

From above, it should be clear that Chevy is probably  making money by selling SparkEV. Then the question becomes, why not sell it everywhere? Why only in few markets (some outside compliance states)? Indeed, Chevy had announced much wider sales in the beginning, only to cancel them later. They wouldn't have done that if it was compliance only car. This involves guessing, so I'll present a few.

One reason could be the US federal tax credit for EV. Each car maker is allowed 200,000 EV sold before the tax credit is sunset. Chevy has already used up about 100,000 with the Volt and Cadillac ELR. If they use up all the tax credits before their upcoming Chevy Bolt is released, the fear is $7500 higher price than the competition (Tesla Model 3, new Nissan) will doom the Bolt sales.

SparkEV sold about 950 cars in Apr. 2015 in only 2 states, probably much of it in second half the month when they announced price reduction. Subsequently, they have been constantly sold out in much of the dealers, so the sales figure is less and hard to gauge the demand. But if 950 car in 1/2 month in 2 states (about 20% of US population), nationwide roll out would result in 950 * 2 * 5 * 12 mo = 114,000 cars per year. That'll pretty much wipe out the entire tax credit even before first Bolt rolls out of the assembly line. Even considering 1/5 of that figure (about 35,000 cars sold for 1.5 years before Bolt), that'll eat into tax credit in significant numbers.

Another reason could be that Chevy is being cautious with all battery EV by testing the waters with SparkEV. In case it doesn't hold in limited markets, they're not likely to lose out much. Indeed, releasing in hot climate (Mexico) and cold climate (Canada) is just such test, and it doesn't cost Chevy a dime while they gather valuable data on their BEV performance in the real world. In fact, they probably make some good  profit from conducting the test. And SparkEV drivers benefit from being able to drive what is the best BEV for the money available in the market today. Everyone benefits without too much risk for Chevy.

Then there's the gloomy reason: Chevy isn't serious about BEV, and SparkEV is a ploy to keep green naggers off their back. In Mexico with the awful air quality in some cities, selling SparkEV would be a ploy to get people to Chevy showrooms. In Canada, well, there are some crazy Canadians who dare drive EV there, too (hi Andrew!). MD is where SparkEV motor is made, so that'll be a good PR for them. Basically, Chevy's main reason for SparkEV is meeting compliance requirements, and doing very little else to keep naggers at bay. But even so, having the best EV in the world available at some places is better than not having it at all.

It could be combination of reasons, different reasons, no reason at all, who knows? But above try to make some semblance of reasons why Chevy is doing what it's doing with SparkEV limited release. Sometimes, human mind just keeps asking, "why? why? why?"

But one thing is clear. Mr. Maury Povich, take it away.

SparkEV, you are NOT a compliance car.

Edit Nov. 19, 2015

If SparkEV is a compliance car, how many cars would Chevy need to sell to qualify? We don't know exactly, but we can get some clues from other compliance car sales. According to, Oct 2015 sales report, Fiat 500e sold 5539 cars while SparkEV only sold 2311 cars.

SparkEV is selling for about $7000 cheaper, leasing for $1600 cheaper, it's quicker, it has DCFC. One would think that SparkEV has some other major problems, and thousands of them are sitting at dealer lots. But that isn't the case. SparkEV is constantly sold out. In fact, I'm surprised that they managed to sell even 177 cars in Oct. 2015. Where are they selling? It's not in SoCal as it's been sold out within 250 miles of here for since June of 2015.

Fiat 500e is selling more than twice as many as SparkEV, a car that supposedly loses $14,000 for each sold and their CEO famously quoted as saying they won't sell a single car more than necessary. That suggests Chevy should make lots more SparkEV to meet the demand to meet compliance; having it sold out makes no sense.

Then why not sell more SparkEV? Demand is certainly there judging from sold out dealers. There is no way to know for certain unless you're the decision maker at Chevy. But the clues seem to indicate that they are trying to save federal tax credit for the upcoming Bolt. It's the only logical explanation for selling fewer SparkEV than Fiat 500e.

But then, GM hasn't always been logical, such as when they scrapped the EV1 program that included hybrid models after spending billions on research. Meanwhile, Toyota went on to become the world leader in auto sales, probably thanks to the positive perception brought by the Prius, which was probably crappier than EV1 hybrid.

GM has great engineering talent as shown by EV1 (many Tesla engineers previously worked on EV1), and now the SparkEV. Let's hope that GM executives have caught up to their engineering talent and do the right thing this time and not let the almost sure thing slip through their grasp again.

Tuesday, November 10, 2015

SparkEV destiny

I don't know if this is true, but this post was found in Tesla motors club forum by a user named "Red". If true, Spark was destined to be an EV, and EV is merely fulfilling its destiny. I sincerely hope that it can live on as EV for a long, long time. May you live long and prosper, SparkEV.

"GM wrong about itself

Actually GM is wrong when admitting the Spark was not designed as an EV.

It actually was, just not thoroughly, because it was one of the earliest ones. Spark is basically a reworked Daewoo Matiz, which was originally designed by Italdesign for a partnership between FIAT and the EV drive train pioneer Miro Zoric, who created the first inverters for AC motors, yes, even those in the Tesla. First for industrial use and then for automotive use. He also made first drive trains for GM's EV1, for instance... AC motors were a non existing option for cars before that. They were not controllable. In a way, due to that breakthrough, today batteries are the narrow throat, since AC drive trains are usable and efficient now.

Anyway, what was later known as Matiz, was originally intended to be FIAT's first electric car. A small but zippy city commuter. Due to administrative issues, Gianni Agnelli's desire to have each FIAT model also have an electric version by 2000, was put aside and Daewoo bought the Matiz design and GM later bought Daewoo and renamed Matiz into the Spark. So in terms of legacy, the Spark did start out as a would be EV, but not in the way most would think.

And it was originally supposed to have an AC motor and lead acid batteries, since Mr. Zoric only made rechargeable zinc air batteries (first one in the world) slightly later, in 1997. Because they would take up more space than lad acid, the little car would have lead acid batteries initially and zinc airs were used in buses and trucks. Some trivia "

Thanks, Red. Haven't seen recent posts from you in a while in Forum. I hope you're doing well.

Tuesday, November 3, 2015

Can stock Corvette beat Tesla P90DL in 0-60MPH?

With the recent news about Tesla's announcement that P85D/L usable power is not simple sum of each motor power, it got me curious why much higher power gas cars that weigh less would be slower in 0-60 mph than P85D (or P90DL). The usual argument goes like this.

1. EV has torque available from 0 RPM. But my question is why doesn't the gas car have peak torque available at 0 RPM?

2. EV (P85D/L) does not have to shift gear. But my question is why does gas car have to shift gear?

I thought these are obvious question, but after having some "debate" in forums, it seems people aren't versed in basic Physics and manual transmission to be able to understand what I'm saying. Therefore, if you haven't had basic Physics or you don't understand how manual transmission and clutch works, you should understand them before continuing with this post. It also helps if you know how to pull a wheelie on a motorcycle.

I'm going to be using Corvette Z06 as an example gas car for this post, but it could be any car with comparable performance. While Dodge Hellcat has more power, I can't stand Sergio (their CEO) for making stupid comments about EV and not improving on Fiat500e with DCFC or making better EV, so I won't be using it in this post. Sorry Hellcat; I like you, but not your CEO.

Making an EV out of gas car

Gas cars produce peak torque at specific engine RPM, and fully open throttle. Outside of these conditions, torque is far less. One only has to look at power profile curve to see this. Below is 2015 Corvette Z06 power profile.

If there's a way to keep the engine running at 3600 RPM with FULLY open throttle at 0 MPH, full torque 650 ft-lb from the engine would be available from the very start. Is there a way? Of course there is; simply FULLY open the throttle with clutch disengaged, and the engine will happily rev far past 3600 RPM. Hopefully, it has rev limiter so that the engine doesn't fall apart!

So if there's a way to make the engine speed to peak torque RPM from 0 MPH, how do we control the engine speed with FULLY open throttle so that it stays at peak torque of 3600 RPM instead of going to rev limiter? Simple: clutch slip. If the clutch is allowed to engage partially and allowed to slip, the torque at either ends of the clutch shaft must be the same to keep the engine RPM constant. Essentially, the torque at 0 MPH now becomes peak torque of the engine, not the torque at idle.

Some suggested that clutch slip results in loss of torque; if the engine RPM is kept constant, there is no loss of torque. Some suggested power is lost on clutch; yes, but power to wheels is related to wheel RPM, and clutch friction loss does not enter into the picture. Even for Tesla, instantaneous power at 0 MPH would be 0 horsepower (or watts or whatever unit of power you want to call it). This is why I asked for basic Physics as prerequisite for reading this post.

Doing this requires careful control of the clutch. Some have suggested that such fine control over clutch slip is very difficult or not possible. Or is it?

Enter the Motorcycle

Let me back up here, and give an example of this type of activity being done on daily basis by rank amateurs: motorcycle wheelie. Most motorcycles don't have enough power at low RPM to be able to pull a wheelie. The problem is worse for high peak power sports motorcycles as they have very little power in low RPM. Knowing that even 90cc motorcycles can pull a wheelie that sometimes require 2G of acceleration, something is being done to allow that from even tiny engines.

Don't try this at home, kids. The way they pull a wheelie is to rev the engine at sufficiently high RPM, and let the clutch slip to accelerate much quicker than their low RPM engine torque would allow. On high power sports bikes on the freeway speeds, they "blip" the clutch (don't do it!). Once the front wheel rises and the center of mass has shifted sufficiently, less acceleration is needed, and the clutch is allowed to fully engage. At that point, it's a matter of balancing, and very little power is needed.

It's easier to wheelie with high power sports bikes since they have higher center of mass. Doing this on 90cc motorcycle requires careful dance on the clutch lever for much longer time to allow sufficient wheel rise to take place. Indeed, I tried this many times long ago when I had one cylinder, 250cc 300 lb motorcycle that got 15HP peak power and 80 MPG (only in private parking lots with owner's permission; please don't arrest me!). Even something as wimpy as 20 lb/HP vehicle can pull 2G of acceleration, surely something with 650HP engine at 5.4 lb/HP should be able to pull 1.1G for 2.5 seconds, right?

Gears, shemears

Another problem often cited by EV folks is that gas car must change gears. That's not true. If the gas car keeps it in one gear that'll allow it to run at 60 MPH, there is no need to change gears. Corvette would run under 6000RPM at 60 MPH even in first gear. But clutch slip would be the mechanism to match engine's single RPM (peak torque RPM) to variable wheel RPM, not gear change. Looking at Corvette Z06 gearing, it seems 60 MPH would result in 4161 RPM in second gear and 3128 RPM in third gear. The gearing data is from Chevy web site.

The RPM at 60 MPH calculation is from

Let's use third gear and clutch slip to allow peak torque to take place. Second gear means more torque to the wheels, but we have to remember to fully engage the clutch and allow the engine to rev beyond 3600 RPM within the run. For driver sanity, using the third gear would let him (me!) not worry about RPM other than 3600.


There is one potential problem with this approach, and that is traction. Given that Corvette is RWD while P90DL is AWD with intelligent traction control, putting down all that power may simply spin the rear wheels. Again with basic Physics, static coefficient of friction is far higher than kinetic coefficient of friction.

For example, if Corvette did the run with third gear (1.21 * 3.42 final drive = 4.14), and 26.7 inch diameter wheel, driving force at the contact patch of the tires would be

650 ft-lb * 4.14 / (26.7 in / 12in/ft / 2)  = 2418 lb (each rear tire would be 1209 lb)

Corvette weighs 3524 lb. Knowing that Corvette can pull more than 1G, the minimum power needed to break traction would be 3524 lb. Third gear is not enough to break traction, but that's also not enough to push it quicker than P90DL mode. 2418 lb to push 3524 lb car would result in acceleration of only 0.69G, about that of P85D sports mode. Using peak torque RPM will not allow the Corvette to out accelerate P90DL. Scotty, we need more power!

May the force be with Vette

What we need is at least 3524 lb of driving force. Using first gear, 60 MPH would be 5919 RPM; let's say it's 6000 RPM. At this RPM, there would be about 600 550 ft-lb of torque read from the graph. With gearing 2.29 * 3.42 final drive = 7.83,

550 ft-lb * 7.83 / (26.7 in / 12in/ft / 2)  = 3871 lb

3871 / 3524 = 1.1G of acceleration! We are there! If we keep the engine running at 6000 RPM with fully open throttle and modulate the clutch to keep it there while accelerating, Corvette would pull 1.1G from stand-still all the way to 60 MPH. It's 10% quicker than falling.

This assumes traction holds. This is not "popping the clutch" where the torque at the wheel could exceed the traction limit via flywheel momentum change. This is controlled modulation of the clutch, and the torque at the wheels is not allowed to go beyond accelerating at 1.1G. Whether the stock tire would allow this is unknown, but with rear wheel contact patch pushed down from body torque due to acceleration, I'm pretty sure it will hold, especially considering that skid pad (maximum lateral acceleration) is rated at 1.2G.

At 60 MPH, it is 88 ft/sec. 1.1G is 35.42 ft/sec2. This would result in 0-60 MPH time of (drum roll...)

2.48 seconds!

Corvette just beat Tesla P90DL. HOLY SHEEEEEEE! Oh well, it's only in theory in some obscure blog about a "compliance" EV.

Help me, Obi-won

If this was actually carried out, the price we pay to win may make the victory hollow.

First is the question of traction. We have to get the RPM just at 6000, and no less (more would be ok). If the RPM dips any less, there will be more torque, and the rear tires could make plenty of smoke. The advantage of using the peak torque gearing (third gear) was that no matter which way you go, it's not likely to break traction due to less torque, but that wouldn't be quick enough. One can argue that using higher RPM where less torque is available while keeping the car at 1.0G (2.73sec 0-60 mph) may make it more manageable. Maybe, maybe not. That will take experiments to find out.

And those experiments will cost you dearly. For each run, you're essentially dumping lots of power into the clutch, with standstill dumping almost 600 HP to poor clutch. Assuming that clutch response with all that power (aka, heat) is manageable, it will surely reduce its life. It's not clear how long it'll last. One run? Two runs? I suppose Chevy engineers would know, but would you burn up the clutch on each 0-60 MPH run with ~$100K car? Each clutch job may cost more than 3.25 years of SparkEV lease! It's not likely that anyone would do such a thing, and such run would not be valid, would it?

Leia, I am your experiment

Each time a manual transmission car starts from stand-still, it slips clutch. Each gear change involves minute amount of clutch slip. Basically, clutch slip is normal operating mode of manual transmission cars. If that's the case, extreme clutch slip is not out of the operating mode, although it's not something you see everyday (other than motorcycle wheelies; no officer, I did not pull a wheelie!). Without quantifying what amount of clutch slip is legitimate, slipping the clutch all the way to 60MPH would be valid.

Question is, is anyone nutty enough to do it? Well, there are plenty of people nutty enough to drive a 4 door sedan with electric drive train that can take them from 0-60MPH in 2.8 seconds. Worse, there are those who dare drive a "compliance EV" and damn proud of it! I don't see why there wouldn't be some who would burn up their Corvette clutch for bragging rights.

Now where are my girlfriends, one with Chemical engineering degree who own bunch of Corvettes and another with Electrical engineering degree who own bunch of Tesla P90DL? Are you reading this? ;-)

Edit Nov 4, 2015

After sleeping over this (don't we all dream about cars and/or motorcycles in our sleep?), I think sanity check is in order. We know Corvette's 0-60mph is 2.95 sec. If we assume that clutch is fully engaged as soon as possible off the line and first gear is maintained, we can calculate how long it'll take for 0-60. Then we can compare to actual run time to see how close the calculations are.

Unfortunately, the torque data isn't available, only the graph. We can "eye-ball" some values from the graph and make rough calculations. How far off can we be? As far off as the eye ball and my biases allow!

The torque number we are after is average  torque from lowest to 6000 RPM. It's pretty hard to tell, especially only 2 numbers are available: 650 ft-lb at 3600 RPM and 533 ft-lb at 6400 RPM converted from peak horsepower number. I don't know, lets just guess 450 ft-lb. While it could be higher, torque above 600 ft-lb would result in greater than 1.2G skid pad limit in first gear and resulting tire spin, so one would have to try to stay below it. Assuming 550 ft-lb is used as peak torque, using 450 ft-lb as average would not be unreasonable.

450 ft-lb * 7.83 / (26.7 in / 12in/ft / 2)  = 3167 lb
3167 / 3524 = 0.9G
88 ft/sec / (0.9G * 32.2 ft/sec2) = 3.03 seconds

We are in the ballpark to actual experiment data with our calculations, so I feel more confident that clutch slip method could yield quicker 0-60 mph than P90DL.

Edit Nov. 5, 2015

I just can't seem to leave it alone, can I. I've been accused of being ignorant of Physics and not knowing how manual transmission and clutch works. Of course, both are wrong. It seems people who don't understand basic Physics or who haven't driven manual transmission in many years forget things. Here's a very simple way to picture the concept I present: riding the clutch.

When you were a beginner manual transmission driver, the fear you had while stopped on a hill is rolling back and hitting the car behind you. What you did (or what I did) was to partially engage the clutch while revving the engine so that the car doesn't roll back. Obviously, this wears out the clutch very quickly. What is significant is that you are accelerating via fighting gravity through clutch slip and higher power of the engine than idle can provide.

For steeper hills, you needed higher RPM. 45 degree hill would be about the maximum on most cars due to traction. Then the power needed would be? Physics homework for you! If the hill is 90 degrees and there is traction (fly paper tires?), you'd need 1G of acceleration to avoid rolling back.

The proposal I make in this post is simply "riding the clutch" taken to extreme levels. We know that it can be done at lower power levels; beginners do it all the time. The question of whether it can be done at extreme level requires (expensive) experiments. At least the calculations I present show that it's possible. Now I need to go find girlfriends with ChemE and bunch of Corvettes. BRB.

Edit: 2016-10-20

There's no question that Corvette has enough power to out accelerate Tesla P90DL with proper abuse of the clutch. But the question was if the tires can hold traction. There's an excellent video by Engineering Explained that stock tires probably won't hold traction, and limit it to about 0.8g in RWD cars like Corvette. That is probably why Corvette is rated only for 2.95 sec 0-60 MPH, and even that's very optimistic.

Video does an excellent explanation of normal force and shifting center of mass. With shorter wheelbase, peak acceleration would be much higher. That's why lateral acceleration (as in cornering) on Corvette is 1.2g and probably far larger than linear acceleration since width of the car (left to right) is much shorter than length (front to rear).

So the conclusion is that Stock Corvette will not out accelerate Tesla P90DL only due to lack of traction. But given flypaper tires of infinite traction, (if there is such a thing), appropriate clutch abuse (and destruction) would allow Corvette to out accelerate even P100DL that's rated for 0-60 MPH in 2.5 seconds.

Many arguments given by EV folks that gas cars lack "instantaneous torque" or that gear shifting make them slow are not true. Rather, gas cars are slow for most parts due to drivers' inability or unwillingness abuse the car to the extreme. Even with capable driver (aka, abuser), traction limit would not allow stock gas cars' tires on RWD configuration to be quicker than intelligent AWD Tesla.

Which begs the question, is there a tire combination that will allow properly abused Corvette to be quicker than P90DL or even P100DL? I really need to make more money if I'm to satisfy my curiosity. I should setup a "go fund me" page asking for tens of billion dollars so I could take over GM to be able to run these experiments. Anyone care to donate GM to me?

Wednesday, October 28, 2015

Love letter to Nissan Leaf DCFC users

This love letter is for those who care how Leaf is charging using DCFC. I hope to save money for those who pay to DCFC, and have non-paying Leaf drivers be aware how expensive it can be and hopefully become better members of the EV community. This is as romantic as I get, right to the point!

Previously, I've harped on Leaf's "No charge to have other people wait while Leaf is slow charging" program as well Leaf's slow DCFC speed. I call waiting for Leaf DCFC when L2 would be cheaper as getting "Leafed" and waiting for Leaf DCFC slower than L2 speed as getting "Leafracked". I also call Leaf drivers pulling into and using dual head DCFC when perfectly working Chademo is sitting empty as "Leafrackers".

There's not much I can do about Leafrackers. They are truly mouse frackers, and I don't have much love for them. Don't be a Leafracker!

I don't have much love for getting Leafracked, either. If they're willing to take up a DCFC spot and have others wait while charging slower than L2, they are frackers. Especially bad are those who plug in after their first DCFC when they already have 90% SoC. But there could be some that don't really understand that they're charging so slowly.

While I don't like getting Leafed, those who let others get Leafed may not have much choice. If Leaf battery has deteriorated so much that they cannot get much further than 50 or 60 miles, they may need all the help they can get. Leaf at 60% may only charge at 36kW (instead of 45kW). Even if they pay for charging, they may have to stick around and pay at higher rate until there's enough charge, though switching to L2 at 10kW (80%) instead of 6.6kW (86%) would be nice.

Below are two tables of MPG equivalent to gas car if Leaf has to pay to charge using eVgo OTG plan. It's similar to my MPGe table in that rows are $/gal of gas at local gas station. It uses Leaf's 114 MPGe EPA (3.38 mi/kWh EPA). Reds represent worse than 50 MPG, though many are masked by light yellow row markers.

First table is useful for Nissan Chademo only charger. It is more informative charger, because it shows the current in amps. The voltage is roughly constant at 400 volts, so the second column header (second row) is corresponding power in kW (multiply current by 400 divide by 1000), just for FYI. To find equivalent MPG to gas car, simply look up the closest gas price and current.

For example, if it's 25 amps (about 80%), local gas prices are $2.60/gal (Oct. 2015), you'd be paying equivalent to 14.6 MPG gas car.

Second table is useful for dual head ABB charger. It's not as good, because it does not show power nor current. As such, we have to "eye-ball" and infer the data we need. One can deduce power from energy (kWh) and elapsed time. 0.01kWh in 1 second would correspond to 36kW, 2 second would be 18kW, 3 seconds 12kW, 4 seconds 9kW, and so on. In general, if it takes more than 2 seconds for 0.01kWh (18kW), it's better to disconnect and use L2 instead. That's only with regard to time if others are waiting. If money is your objective, it's better to move to L2 when it takes more than 1 second per 0.01kWh (about 60%)

One can deduce more accurate kW from ABB by doing time averaging. For example, one can count how many seconds it took to get 0.1 kWh, and divide  the time by 10 to get more accurate time for 0.01kWh. Because Leaf slows down so quickly, much longer averaging many not be beneficial, although if you're trying to charge at 95% (hopefully, no one's waiting for you), you may have to wait for about 4 minutes to get 0.1 kWh.

For example, if it's taking 3.5 seconds for 0.01kWh and local gas prices are $2.60/gal (Oct. 2015), you'd be paying equivalent to gas car between 13.2 MPG and 17.6 MPG.

Edit Oct 29, 2015

A commenter by the name of Todd was gracious enough to make measurements of Leaf DCFC, and made a plot of Power vs elapsed time. Following is a quote of his comment.

"The battery was at 24% at start and ended at 88% in 30 minutes. The temperature here in Mira Mesa was 70 degrees @ 10PM. The battery started at 70 degrees and ended at 87 degrees. The rate was 41Kw, increasing to 44Kw until around 58% charge and then it was a somewhat linear drop to about 9Kw over the last 21 minutes. That works out to 34% in the first 9 minutes and another 30% in the last 21 minutes. The last image is showing the voltage of each cell and SOH%."

From what little research I did, GIDS (named after a guy who made Leaf tool?) is actual battery capacity that is used whereas SOC (state of charge) is absolute battery capacity. Like all EV, the battery does not discharge to 0 and does not charge to 100%. When 0% is indicated by the car, there's still lots of energy in the battery. GIDS is what's indicated by the car. As such, SOC is pretty meaningless with regard to driving; only GIDS will be discussed. In fact, when I use SOC in my blog, what I really mean is GIDS.

The plot was made at ambient temperature of 70F, so it's hard to know how it'll translate at different temperatures. It may not be absolutely accurate for all conditions, but it's a guide to make some rule-of-thumb observations to help Leaf drivers.

Left axis is power in kW for Green plot. Right axis is % for GIDS in magenta, battery state of charge in % in red, not sure what black is; maybe temperature?

1. If you're paying eVgo OTG plan to charge, and you have 6.6kW L2, it's best to switch to L2 at 40kW (100A current) to minimize cost. That occurs at about 60%. If you have 3.3kW L2 (2012 and earlier), it's best to switch to L2 at 20kW (50A current), which occurs at about 75%.

2. If you want to optimize for time, the best place to disconnect is when it starts to dip below 40kW, which is about 60%.

3. If you want to optimize for time, and you need more than 60%, it's up to the individual when to stop, but it seems the "knee" occurs around 70%.

4. If you need more than 70%, time taken will be less than optimal, but it will be quicker than L2 up to about 88 85%, taking 15 minutes to gain 15% (averaging about 1% per minute, VERY SLOW!). This would be the maximum charge Leaf should get from DCFC. It's easy to remember: back to the future! Get it? Time optimized, back to the future 88? Yeah, go see the movie! (based on Tom Saxton's data, 88% might not be best; stop at 85%. See below)

5. Based on his charging from 24% to 88% in 30 minutes, you should prorate your charging accordingly. Best would be to plug in at 10% or less to get to 70% in 30 minutes (roughly). But if you're already at 50%, you should only take about 10 minutes to 70%, not full 30 minutes. No-charge-to-charge or not, waiting around to charge wastes time, and I'm sure your life is worth more than $1/hr.

Edit Oct. 30, 2015

As I was researching "GID", I came across another blog (by Tom Saxton?) that deal with Leaf DCFC.

As a test, he charged from 21% to 80%, then plugged in again to get 95%. Hopefully, others weren't waiting while he was doing this! I think he got clever with axis labels. He states he charged to 80%, yet the light blue is "pack kWh" in legend. I suspect he cleverly chose the axis so that %GID and pack kWh line up. As such, pack kWh plot will be used as %GID.

For 21% to 80%, he found it to take 13.2kWh in 26:40 min (0.44 hours). That's 30kW on average, which is roughly similar to eye-balling from Todd's plot. That's also 44MPGe$ from first table above when gas prices are $2.60/gal.

For 80% to 95%, he found it to take 3.2kWh in 36:35 min (0.61 hours). That's 5.25kW on average, far less than Leaf's L2. That's about 7.5MPGe$ from second table 5.1kW column when gas prices are $2.60/gal.

Far more troubling is what happens at 88%. Basically, it stops charging for 8 minutes while you're paying by time; $0.80 gone to dollar heaven! In addition, first 3 minutes of charging adds more energy than 33:35 min after. This is probably what I saw some Leaf at >90% charging less than 2kW with DCFC. Talk about wasting time!

Based on this data, maximum recommended DCFC level would be 85% (3% margin from 88%). Otherwise, you risk being in charging limbo at 88% for 8 minutes. But you should still disconnect at 60% (40kW) or 70% (~20kW "knee" region of slowing) if you can live with it. After all, why waste time and money needlessly?

Saturday, October 24, 2015

Jerks all around us: ICED, Leafed, Leafrackers

NOTE: It came to attention that "Leaf**k" is not safe for work (NSFW). Taking cues from Battlestar Galactica, all instances of "Leaf**k" has been replaced with Leafrack.

We sometimes think that we're a small community of EV drivers. If you ride a motorcycle, you know the feeling; we wave to each other, knowing that death may fall on us the very next minute by an errant douche, and genuinely glad to see a fellow motorcyclist. For EV, some Dicks (Richards?) may decide to cut all EV programs. When EV drivers meet at fast charger, where we sometimes stick around since it often only takes 10 or 15 minutes (except Leaf), we make a friendly chat as kindred spirits. But the world is not as such. There are plenty of jerks around.

Leafed and Leafracked

If you are unable to charge, because there's Leaf charging at rate slower than 6 times L2 rate (6*6.6kW = 40kW), then you're getting Leafed. Why 6 times? Because DCFC is 6 times more expensive than L2, and people who have to pay for charging would disconnect if DCFC gets slower than 6 time L2 rate. But hold on. You might ask, "why do you call it getting Leafed when all EV slow down charging as the battery fill up?"

First reason to calling it Leafed is that Leaf's fast charging is not very fast compared to SparkEV (and probably all other EV since only Leaf lacks thermal management). It starts out fast enough, but it slows down very quickly. Since Leaf gets below 40kW even when they have 60% state of charge, you're probably getting Leafed any time there's a Leaf in fast charge spot. Some Leaf slow down to as low as 2kW from 50kW charger!

Let me pause here and tell Leaf drivers how DCFC pricing works, because I've heard comment that "it's the same thing at 1kW or 100kW, because electricity is charged per kWh." eVgo charges electricity by time, not energy: $0.10/minute ($0.20/min for non-OTG plan). The longer you're plugged into the charger, regardless of kWh of energy used, the more money you pay. Therefore, the slower you charge, the more expensive it gets for energy. Meanwhile, L2 is $1/hr, 1/6 as expensive per time as DCFC.

How expensive can DCFC get? At 6kW (Leaf DCFC at 88%, which almost all Leaf I've seen go beyond), you'd be paying about $1/kWh (or $2/kWh for non-OTG plan). With $2.60/gal gas prices these days, you'd be paying more than 10.5MPG gas car (or 5.25MPG gas car for non-OTG plan). At 2kW (some Leaf at 95%), you'd be paying more than 3.5MPG gas car (or 1.75MPG gas car for non-OTG plan). Those are using SparkEV efficiency figures; Leaf could pay even more due to lower efficiency.

Which brings to second reason to calling it Leafed. Leaf drivers use fast charger to charge slower than their 6.6kW L2, because Nissan gives out free charge for 2 years. They call it "no charge to charge" program. I call it "no charge to take up fast charge spot and have everyone wait while slow charging" program, because Leaf charges so slowly. Since it's free, Leaf drivers don't care that they're charging slower than L2 or plug in when they already have 90% charge in battery to take up full 30 minutes and charge at 2kW (worse than 1.75MPG gas car). After all, why bother spending the time to move the car to L2 when it slows down when fast charge is free for them?

We have various degrees that we can distinguish for getting Leafed as follows. The percentage numbers are from few observations I made of Leaf battery state of charge and corresponding charging speed. Percentages will vary depending on ambient temperature and how hard Leaf was driven before plugging into fast charger and other factors.

Greater than 40kW (0% to 60%) = A OK, Normal charging.
40kW to 6.6kW (60% to 88%) = Getting Leafed.
6.6kW to 1kW (88% to 100%) = Getting Leafracked (Leafed and fracked)

Almost all Leaf I've encountered at DCFC Leafracked others to some degree, including other Leaf.

SparkEVed not likely, i3ed but never fracked

Since all EV slow down as the battery is filled, the problem is not unique to Leaf. But Leaf is most abundant source of the problem due to its slow charge and free charge. For example, getting SparkEVed would entail the following. SparkEV has 3.3kW L2, so the thresholds would be 20kW and 3.3kW.

Greater than 20kW (0% to 92%) = A OK. Normal charging.
20kW to 3.3kW (92% to 100%) = Getting SparkEVed.
SparkEV charges at 9kW at 99%, so there's no way to get SparkEVed and fracked.

Since it gets more expensive as it gets slower than 40kW, SparkEV driver would disconnect as close to that as possible (about 85%), so one isn't likely to ever get SparkEVed. However, BMW gives free charge, so one may encounter "i3ed", although not likely to get fracked at the same time since they charge fast enough. Getting regularly Leafracked can only come from Leaf. 

Getting Leafracked is bad for all EV, including Leafs. If a Leaf driver is waiting to charge, and there's a Leaf already there, chances are he's getting Leafed, and probably getting Leafracked half the time. Basically, getting Leafed sucks the life out of all of EV community, including Leaf.


I mentioned in previous posts about Leaf taking a dual head CCS-Chademo charger while perfectly good Chademo charger is next to it. I call them Leafrackers. You can read about my first encounter with a Leafracker. Scroll down in the link below.

It is not the same as finding a Leaf charging from dual head while Chademo charger is empty; it could be that when the Leaf first pulled up, Chademo was being used. Since the driver wouldn't be around, there would be no way to move it after Chademo freed up, so that would be a legitimate use of the charger. Even if the driver is around after Chademo subsequently became empty, not moving the car is acceptable; I mean, if the driver had gone to eat while charging, you wouldn't expect to drag him out of the restaurant to move the car. It would be nice for him to move the car (LeafSaint?), but not bad if he doesn't.

The specific incident when you find a Leafracker is when you observe someone pulling into dual head charger when the working Chademo charger is empty. As such, finding Leafracker is rare, since you must witness it.

Or is it? Was that really the first time I encounter a Leafracker in my post? I've seen many Leaf charging from dual charger while Chademo was empty, but I always assumed that there was another using Chademo when they pulled up. After all, why would they purposely use dual head and block CCS when perfectly good Chademo is available? I mean, EV people are nicer than that, right? Don't we meet the nicest people in EV?

Just today (Oct 24, 2015) as I was charging, a Leaf pulled up and tried to use the dual head charger when Chademo was empty. Now I'm not so sure if Leaf people are as nice as rest of EV people. Based on this, I suspect there are many more Leafrackers than we realize. Maybe even most of those incidents when I saw Leaf using dual head chargers were Leafrackers, not merely having Chademo already taken when they pulled up. Of course, there is no way to know; I'm just getting paranoid.

Leafrackers are most damaging to CCS cars such as SparkEV and eGolf. But the wait caused by CCS can lead to waits for subsequent EV, including other Leaf. That actually happened in the case I mention in my first encounter with Leafracker. My 30 minutes of getting Leafracked by Leafracker resulted in 16 minutes of wait for another Leaf. Besides, when you have EVs needlessly waiting around to charge, it's bad for entire EV community reputation. Gas bags would say, "EVs will never work. Just look at them waiting to charge even when EV is tiny percentage of gas cars."

Not only Leafracker

You might say that Leaf isn't the only Chademo charging car. That is true. One can theoretically encounter iMievfrackers or SoulEVfrackers. But in reality, Leaf is the only Chademo car that gives free charging, and they are far more likely to plug into the fast charger at high state of charge and keep it plugged in due to Leaf's slow charging.

When iMiev or SoulEV plug in, they are likely to do so only when absolutely necessary since they must pay. They are also likely to reduce their time at the charger since slowing charging as battery accumulates more energy means far more money out of pocket. It's like the sound falling tree makes in the forest when no one's around; there may be iMievfrackers and SoulEVfrackers, but if you don't encounter them, their impact is irrelevant. Meanwhile, I've encountered real life Leafrackers, maybe many, many of them.


If a car is parked in EV charging spot while it's not charging, and you are unable to charge, then you have been "ICED". ICE stands for Internal Combustion Engine. In the early days of EV (circa 2011), there were very few EV public charging, and most of those blocking EV charging spots were (are) gas cars (ICE cars). That's where the term comes from. Obviously, if a gas car parks in EV charging spot, you cannot charge, so you would be ICED.

But today, there are many EV (in SoCal). Some who drive EV treat EV charging spots as privileged EV parking spots instead of charging spots. I have been ICED by TeslaS parked in CCS charger spot. I waited about 30 minutes until he came out, and I told him not to park at charging spot since he cannot use CCS charger. His response? He just went in the mall to get something quick, and there was no other parking. Bull! There were plenty of parking, but CCS spot happened to be closest to the shop he wanted to visit. Yes, you can get ICED by Tesla. Those with expensive cars shouldn't piss off those who drive cheap cars.

I was told by a BMW i3 driver that a Volt was parked in fast charger spot. I presume Volt was not charging, because she said she was ICED by Volt. If Volt was not plugged in, it would be ICED. But if Volt was plugged in, but full and taking spot to prevent others from charging, would that be ICED? I think it would be. But if Volt is charging at L2, but taking fast charge spot making others unable to fast charge, would that be ICED? No, because he is charging. But I'd call him a Voltfracker.

In another incident, there was Fiat500e using L2 charger at fast charger spot with the L2 cord stretched out far. It's impossible to know why she did that, but I suspect she just got the car, and didn't know what parking stall to use. She had dealer temporary tag made on the previous day. I think she'll learn to use proper spot in the future; I mean, there's no point in charging farther away from the charger than necessary when all she can use is L2. Still, if one cannot use the fast charger, because someone is using L2 at fast charger spot, would that be ICED? That would be similar as Volt case above: Fiatfracker (Sergio is a special kind of Fiatfracker).

L2 EV purposely preventing fast chargers while themselves are charging at L2 is rare. I've never encountered it. However, I have seen them ICE the spot (ie, they're not charging).

State of the jerks address

New York Times had an article on just this topic: EV jerks. They did not explain what chargers were having issues, but it sounded like all of them were L2 at workplace or other form of free charging. Getting Leafracked and Leafrackers are rare since there are fewer DCFC relative to L2, although I seem to be getting Leafracked every time I have to wait for a charger.

Frankly, I'm surprised that there aren't fist fights or even gun fights breaking out over public L2 and free charging. If someone unplugs public L2, that could mean hours of lost time; may even have to spend the night at the office, call a cab, or, heaven forbid, ride the bus! In a world where people drive half way across town to save $0.01/gal of gas, they'll go to even more extremes when it's free.

The problem with public L2 will only get worse. There is no way to meet the demand no matter how many are put in, especially when it's free, because not everyone uses assigned charging spots. As such, some locations will have more EV than public L2 during certain times, and others will be left empty. If they can get off the charger quickly, problem is less. But L2 takes hours.

Combined this with more jerks adopting EV, and the problem will be severe. Gun fight will break out. And no, banning guns won't work. By the way, definition of assault weapon is "scary looking gun, typically used in movies", and not much to do with its function.

The solution? DCFC, but with penalty for using it for longer time. But for now, we have to deal with jerks. Maybe there's few, maybe there's many, but what is certain is that more will be adopting EV. Hopefully, this post illuminates the problems facing us, and solutions will be implemented in the future to prevent jerks from EV getting ICED, Leafed, Leafracked, and Leafrackers.

Edit Oct. 26, 2015

As I was perusing comments section in Plugshare for a place I charged, I came across comments from a 2014 Leaf owner. Apparently, he is aware of the problem, though i don't know if he links it to free charging or if he'd appreciate those bad behaviors being called "getting Leafed / Leafracked". He also had to use dual head charger few times when his card did not work in Chademo only unit; that doesn't make him Leafracker; he at least tried to use Chademo but failed.

Knowing that there's at least one like him, I have some hope. I wish there are more like him. I also wish he's a she, not a he. :-)  Following are some of his comments out of several dozen of them.

"Oh my god! Same guy from before who plugs and charge for 30mins on the Chademo,comes back to his car and replugs his car again even if he is already above 95%. White SL leaf with no license plate yr 2012."

"Have to wait for this guy for 20 mins before his 2nd session on the chademo terminal is over. He should have just plugged in to the lvl 2 port instead if he wanted to top off."

"Lvl 2 charger can deliver 3.95kWh in 30 minutes. For a 2014 SL LEAF that's 16%. Please use it as a guide especially if you're close to 80% charge already and wanted to get close to fully charge. Instead of using the DC fast charge."

Edit Nov. 9, 2015

After getting heavily Leafracked (waiting 20 minutes for a Leaf at > 90% charging slower than cold molasses in Arctic winter), I wasn't in any chipper mood for another Leaf. After about 5 minutes into my charging, another Leaf pulled up and said in chipper voice, "it's a busy night" to which all I grunted out was "it sure is". Well heck, if it weren't for getting Leafracked by the first Leaf, it wouldn't be that busy!

Another few minutes later, a BMW i3 pulls up. Since there were only 2 fast chargers, he had to wait. Few minutes later, the Leaf driver comes out and unplugs his car and tells the i3 driver "I'm at 70%, and I can come back later. Why don't you charge your car now?" WOW! This guy is LeafSaint placing the need of others above his!

Or is he? Maybe he knows that Leaf charges slower after 70%, so he decided to unplug to save his time. Or maybe he read / heard that some guy writing SparkEV UNOFFICIAL Blog has been nagging about getting Leafed and Leafracked.

Actually, it doesn't matter why he did that, but that he did give up his charging as it's slowing down. He is LeafSaint whichever way you look at it. A huge thank you, and the very first LeafSaint award of the month goes to you!

Thursday, October 22, 2015

Money MPGe$ for various EV

NOTE: For our metric friends, L/100km$ tables follow the MPGe$ tables in bottom half of this post.

I established true out of pocket cost MPGe using actual measured data early in my blog. After all, the amount of money I pay compared to gas car is what matters to me, and probably to most people as well.

I used to think that everyone knew this, but apparently, most people were (are?) oblivious to it; they believe they're getting 100+ MPGe, because EPA tells them so. While that's true with regard to energy consumption, that's not what most people are expecting. When they hear MPG, they think of the money they'll spend / save. Telling people that EV gets 124 MPGe is committing fraud without telling them that MPGe doesn't have much to do with money.

In this post, I present various tables that show out of cost MPGe (MPGe$) for various cars. For SparkEV, I was able to measure the actual mi/kWh, and have an accurate table in link above. But for other cars, I have to infer mi/kWh from EPA's MPGe figure.

First, these are EPA MPGe converted to mi/kWh using 

mi/kWh = MPGe / 33.7kWh/gal

Note that mi/kWh inferred from EPA is about 20% lower for SparkEV compared to actual measured mi/kWh. Therefore, it could be that other cars also have higher mi/kWh when actually measured. In any case, the table should give you an idea of MPGe$, which you can boast (or feel shamed) when speaking with gas car drivers for apples-to-apples comparison.

Wednesday, October 21, 2015

Radio interference by Leaf or Chademo or ?

I sometimes listen to AM radio. While most of it's junk, there's a show called "Tim Conway Jr. Show" on KFI 640AM. One of their programs is called "What the hell did Jesse Jackson say?" where callers hear a snippet of some speech by Jesse Jackson and try to guess what he said. It is HILARIOUS! No, I don't think it's racist, although I wish he'd have other hard to understand figures, such as "George Bush" specials; I mean, it's NU-CLEAR, not NU-QULAR.

I was listening to this show one night while fast charging, and the radio went bonkers all of a sudden. It was not static, but some sort of buzzing (PWM?) that completely wiped out the reception. I didn't know what it was at the time. Oh well, back to audiobook.

In another time, as I was pulling into charge with the AM radio playing with Leaf already charging, I noticed that buzzing got worse as I got closer. Then it dawned on me; it's Leaf charging. Over the next few weeks, I observed that interference was not only from Chademo only charger (Nissan made?), but dualhead ABB charger as well when Leaf was plugged in.

So the culprits for the interference could be any combination of the following: Chademo standard; Chademo chargers (Nissan and ABB); Leaf

Unfortunately, this will come across as Leaf bashing, but that's not the case. If I encounter other EV and I remember to test the AM radio, I would. But these days, it seems only EV using fast chargers are Leaf. If you happen to see EV charging, please try to test the AM radio.

More unfortunately, BMW i3 in US does not come with AM radio (supposedly, EU version does), so they can't test it. I3 drivers are missing out on a very entertaining show!

By the way, please don't go complaining to some government agency if you find interference. If you'd like to complain, you can put comments below or contact the companies. I'm hoping the industry will fix itself if there's a problem rather than involving the big brother.

Edit Nov. 9 2015

As I was waiting to charge next to a Leaf (getting Leafracked; >90%, slower than molasses in Arctic winter) and a SoulEV, both using ABB chargers, I was able to listen to the AM radio. This was in LA where the station is based, and there was no interference! It seems the interference problem is not universal, and strong AM signal could result in no discernible interference from Leaf.

But in San Diego, the radio is clear as in LA. The signal may be weaker, but the AGC (automatic gain control) of the radio would compensate. If there is much stronger interfering source, such as charger and/or Leaf, it would wipe out the signal. Unless there is a way to determine RSSI (received signal strength indicator), it would be difficult to know when the interference would be so bad as to wipe out the radio. I suppose I could get some Ferrite loop and make crude spectrum analyzer and ...

NO NO NO. I am not getting involved, despite how tempting the dark side may be!

Wednesday, October 7, 2015

Free charging SUCKS!

If something is free or low cost while the supply is limited, it gets sold out and shortages result. Unintended consequences result, often at terrible outcome. For example, during storms, people buy stuff they may not necessarily need to have, but just in case they need it. Because the stores cannot raise prices to discourage "just in case" buying, they inevitably run out. Then the people who desperately need those items cannot buy them at any price, even if that item could save lives.

This is the (HUGE) problem with free fast charging programs offered for BMW i3 and Nissan Leaf. They offer 30 minutes of free fast charging for a year or two. Since fast charging is free, the drivers use up all the time they can, whether they need it or not. This results in waiting in line, sometimes for hours, for everyone. Since Nissan Leaf is most widely available EV, they cause the most problem. Compounding the problem is Leaf's slow DCFC rate.

They have 79% state of charge (SoC)? Plug it into DCFC and wait 30 minutes to get 95% SoC. Then plug it in again for 30 minutes to get to 99% SoC. Then plug it in again and go shopping for yet another 30 minutes to get 100% SoC, never mind that 100% was reached after 5 minutes. Hey, they are entitled to 30 minutes, and it's free. Why not?

Above is an extreme example, of course. But the problem is that every charging session becomes 30 minutes instead of 5 or 10 minutes of pick me up. Now multiply this 30 minutes by every Leaf and i3 owner, and you can see the problem. Why charge with L2 when 30 min DCFC is free? Who cares if DCFC is only charging at 1kW when 30 min DCFC is free? Why charge at home or at work when 30 min DCFC is free? Why wait until I'm below 80% when 30 min DCFC is free?


The problem is made worse by Leaf's slow charging. If it would charge like SparkEV (45kW to 80%, taper to 9kW at 99%), guys who plug in with 80% SoC may be done after 10 minutes. But with charging slowing down so quickly, I've never seen a Leaf reach 100% SoC on DCFC. This means every DCFC by "no charge to charge" result in 30 minutes of waiting.

Meanwhile, guys who have to pay (SparkEV, eGolf, etc) pay attention to how we're charging. DCFC is 6 times more expensive than L2, so it's better to disconnect and use L2 when it gets slower than 40kW (6.6kW * 6) or 20kW for 3.3kW L2 chargers like SparkEV. Also, MPGe could cost more than 1 MPG gas car if we let it sit. Basically, EV that pay to charge do not hog the charger, because there's penalty for doing so. That penalty can be very steep if we let it sit.

If there are enough chargers to go around, this is not a problem. But at key places like intercity areas such as "Shops" in Mission Viejo or Carlsbad Mall to get to LA/OC/SD, they are almost always occupied, even at late night. This makes for waiting for 2 or 3 Leafs before being able to charge, sometimes 2 hours of waiting.

Following are some personal experiences. One Leaf was charging at less than 2 kW with 10 minutes left to go at Carlsbad mall with 3 other cars waiting. Another Leaf at "Shops" was charging at 3 kW with 2 other cars waiting. Another Leaf at San Diego was charging at 4 kW at 95% with 1 other car waiting. You can read about how I determine the rate by reading my previous post.

Here's a quote from plugshare comment.

"Great selection of charge plugs. The 50W CHAEDMO stooped charging at 85%. We needed more and charged second time. Starbucks in walking distance."

Obviously, she charged for 30 min to 85%, then another 30 min (to 95%?) while away at Starbucks! I have to wonder if she knew she's charging slower than L2, and whether there were others waiting, or they saw that it's occupied and left in frustration. She could've saved others' time by switching to L2. I don't know if Leaf would charge as high as 6.6kW using L2 at 85%SoC, but it certainly wouldn't take any more time than DCFC. But hey, DCFC is free, why not hog the spot?

If you're coming fresh into EV, you hear "30 minutes fast charge!" and think that it'll be 30 minutes. But when 30 minutes typically turn into 1.5 hours (wait for 2 other cars ahead with "no charge to charge"), it makes for sour EV experience, especially when you really need it for those rare intercity travel. It gets very frustrating. Am I going to get another EV, even the upcoming 200 miles range one, and put up with this crap or just get a gas car?

If I'm a conspiracy theory kind of a guy, I'd say Nissan and BMW are deliberately trying to kill EV adoption by giving "no charge to charge".

As much as I hate free stuff causing shortages, they could've implemented as "free to 80% SoC". That way, only the fast charging portion of fast charging would be free. It would also discourage abuse by those charging at 90% SoC to  try to get to 100%. But of course, there may be other issues, such as regulatory hurdle in only allowing pricing by time, and pricing by energy to be illegal. So maybe there is bigger conspiracy by the government along with Nissan and BMW to kill EV adoption with "no charge to charge" program.

Edit 2015 Oct. 17

As I was pulling in to charge, there was a Leaf that just plugged into dual charger and the driver ready to leave to go shop. Meanwhile, the dedicated Chademo was left empty. I politely explained how there's dual head and asked her if she can move the car so I don't have to wait 30 minutes for her car to finish. She said she just plugged in, and didn't feel like moving the car! I was going to dish it, but I didn't want to make a scene.

After she left, I saw her Leaf's state of charge in the beginning: 76%! It started out quick enough, but soon it was charging at 16kW. At 90%, it was charging less than 6 kW (taking over 6 seconds for 0.01kWh as shown in the video) with 11 minutes left to go. This is slower than L2 charging speed while she's taking dual-head fast charge spot.

"I'm entitled to free 30 minutes. Whether I'm charging slower than L2 using dual head fast charger when I could've used Chademo doesn't matter. I'll take this spot even if I don't charge!"

Meanwhile, a Kia SoulEV pulled into Chademo only slot after about 20 minutes into her charging. Few minutes after I started my charge, another Leaf pulled up. Then the offending Leaf driver came back to move her car some 40 minutes later. Because she wasted 30 minutes of my time, second Leaf now has to wait for me to charge. I go to 80% (it gets expensive beyond that), so it only took 16 minutes. Had the offending Leaf moved her car to Chademo charger in the beginning by spending 2 minutes, I would've saved 30 minutes, the next Leaf would've saved 16 minutes. Senseless waiting all around.


Free charging is not only bad, but it fosters non-caring and entitlement attitude. This can only go bad to worse for EV adoption.

Wednesday, September 30, 2015

Why SparkEV by SparkEV Blogspot

As of Sep. 2015, these are my reasons for SparkEV.

Look! Out on the road! It's quick! It's quiet! It's SparkEV!
Yes, it's SparkEV. A fantastic EV that's risen from the ashes of crushed EV1. SparkEV, which can out accelerate any new car under $20,000 in 0-60 mph and more efficient than any EV in its class. And who, disguised as a mild mannered five door subcompact car with safety of 10 air bags, fights a never ending battle to reduce importing oil from ISIS, Russia, Venezuela, and EV stereotype of over-priced, under-powered glorified golf cart that can only drive 80 miles a day.

1. SparkEV costs as low as $13,500, which is cheaper than Spark gas version.
Spark EV MSRP = $25,000 - $7500 (federal tax credit) - $4000 (CA rebate) = $13,500
Spark gas MSRP with automatic transmission = $15,100
*note: Income greater than 3 times poverty level qualify for only $2500 CA rebate. 3X poverty level is about $45,000/yr for single, bit over $60,000 for family of 3. Income greater than $250,000/yr do not qualify for CA rebate.

2. SparkEV lease could cost less than $1,500 used car.
SparkEV GM factory lease of $139/mo for 39 months with zero down = $5421
CA rebate = up to -$4000 (-$2500)
Total lease cost = $1421 ($2921)
*note: New car insurance is higher, but that's offset by fuel savings and practically zero repair and maintenance of SparkEV. Individual savings will vary depending on used car's condition, insurance premium, driving habits, and subsidy eligibility.

3. SparkEV is quickest new car under $20,000 in 0-60 mph, EV, gas, diesel or anything else.
SparkEV = 7.2 seconds ($13,500)
Mazda 3 with 2L engine / automatic = 7.7 seconds ($19,995)
VW Jetta with 1.8L Turbo / automatic = 7.4 seconds ($22,815)

4. SparkEV is quickest EV under $30,000 in 0-60 mph.
SparkEV = 7.2 seconds ($13,500)
Mitsubishi i-Miev = 13.0 seconds ($23,000-$11,500=$11,500)
Fiat 500e = 8.7 seconds ($32,600-$11,500=$21,100)
Nissan Leaf = 9.4 seconds ($32,950-$11,500=$21,450)
BMW i3 = 6.5 seconds ($43,395-$11,500=$31,895)
Tesla P90D = 2.8 seconds ($119,200-$11,500=$107,700)

5. SparkEV is most efficient EV under $30,000 (lowest use of imported oil) .
SparkEV = 119 MPGe ($13,500)
Mitsubishi i-Miev = 112 MPGe ($23,000-$11,500=$11,500)
Fiat 500e = 116 MPGe ($32,600-$11,500=$21,100)
Nissan Leaf = 115 MPGe ($32,950-$11,500=$21,450)
BMW i3 = 124 MPGe ($43,395-$11,500=$31,895)
Tesla 70D = 101 MPGe ($75,000(?)-$11,500=$63,500)
*note: US electric grid is energy independent in that it uses virtually no imported energy. Oil is up to 60% from imported sources (in 2006) such as Russia, Venezuela, Saudi Arabia, and "blame" Canada.

6. SparkEV can fast charge 80% in 20 minutes (able to drive over 1,000 miles in single day).
SparkEV with fast charge option = Combined charging system fast charge (CCS)
Fiat 500e = no fast charge available
Mercedes B class = no fast charge available
Nissan Leaf with fast charge option = Chademo fast charge
BMW i3 = Combined charging system fast charge (CCS)
Tesla Model S = Tesla Super charger
*note: 65 mph driving for 1 hour and 10 minutes to get off/on highway and 20 minutes to charge, get food/coffee, use bathroom would result in 44 mph average speed. 24 hours would result in theoretical 1056 miles. Without fast charge, even 130 miles would take upwards of 8 hours. Fast charge is a must for any EV.

7. SparkEV uses smallest battery in EV that gets over 80 miles range per charge.
SparkEV = 19.5 kWh, 82 miles range
Fiat 500e = 24 kWh, 87 miles range
Nissan Leaf = 24 kWh, 84 miles range
BMW i3 = 22 kWh, 81 miles range
Tesla P90D = 90 kWh, 300 miles range
Chevy Bolt = ??? (50kWh? 200 miles range?)
*note: Small battery means potentially lower replacement cost after warranty period of 8 years. It is estimated that Lithium battery raw material prices are around $100/kWh, an eventual lowest cost for battery.

8. SparkEV uses thermal management (liquid cooling) for battery.
SparkEV = liquid cooled thermal management
Nissan Leaf = blow hot air
Tesla P90D = liquid cooled thermal management
*note: Liquid cooled thermal management increases battery longevity and faster charging by better dissipating heat generated by charging and discharging process.

9. SparkEV is safe, practical, and works well with fostering homeless dogs.
SparkEV = 5 doors, 10 air bags (think of Pathfinder landing on Mars), high head room
Fiat 500e = 3 doors, difficult rear seat access when used with doggie barrier
Tesla P90D = would you want to have its leather interior covered with dog hair, windows splattered with drool, and sand on floor/seats from dog beach?
*note: Volunteer to foster homeless dogs and/or adopt foster dogs. It's a rewarding experience for humans and saves dogs' lives. SparkyV will thank you.

10. SparkEV has been sold out in much of So Cal since about mid May 2015. Reason is obvious; it's the best car for the money, EV or gas. Grab'em if you can before they sell out again!

If you want to see how SparkEV stacks up against other EV, see