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Tesla Model S checks in at an unimpressive 89 MPGe

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regman · · 5 years ago

The official label range and MPGe numbers were finally released at 265 miles range and 89 MPGe combined (88 city, 90 hwy). I personally am a little disappointed in the MPGe number but the range came in higher than I was expecting (although lower than the 300+ mile range that has been stated in the past).


· cintech (not verified) · 5 years ago

Why so low? Does it take alot of energy to charge the batteries? What else is in the equation besides cost to charge and miles driven?

· · 5 years ago

It is probably the larger size, weight, and high performance tires that make the Model S consume more energy than the compact EVs such as the Leaf and the "I".

· Anonymous (not verified) · 5 years ago

cintech, so you expected them to include how much energy it takes to charge the battery? Well they don't, they don't care where it comes from. They don't include generation and distribution loss, etc. They simply assume it appears in the battery. Then they equal one gallon of gasoline to 33.7 KWh and calculate the MPGe. If they had included the energy it took to convert a gallon of gasoline to electricity, transmit it on the grid and load it into the battery, the MPGe would be very much lower, maybe a third of 89.

· · 5 years ago

Yes, Anonymous is correct. Just like we don't discount the energy used to make, ship and then distribute the gasoline you burn either. I guess some people think that gas just magically appears in their tank when they need it.

· Jeffhre (not verified) · 5 years ago

Tom that's true. But where did this line come from?"If they had included the energy it took to convert a gallon of gasoline to electricity..."

Transmission losses can be up to 11% depending on the distance the energy travels. But does anyone actually convert a gallon of gasoline to electricity? That's clearly a loss that will never happen.

· Bill Howland (not verified) · 5 years ago

I'd be interested to see hard figures here. I charge my Tesla at 30 amps @ 240 which is for this vehicle its most 'efficient' charging range (30-40 amps). At higher currents, there is much more energy wasted in heating the garage in the summertime. At low currents/120 volts, same thing, the juice goes into heating the garage and not so much charge the battery. So to get 53kwh stored in the battery takes about 75 kwh (best case). It can be bad as 85 at 70 amps im told, and I bet its alot worse at 12 amps @ 120 volts. Soon Ill do a test to see just how bad it is.

So, Is the Model S similarly plagued by a low efficiency charger system as is my Roadster? Any one who has hard figures for the Model S please post them in this blog.

My other EV, the VOLT, seems very efficient charging, whether at 8 or 12 amps 120; or 14 amps @240.

· · 5 years ago

I don't know about the Model S Bill, but I've measured my ActiveE at the wall and it takes about 32kWh's to completely charge the battery which has 28 usable kWh's so about 11% is wasted.

· · 5 years ago

@Bill Howland
"Is the Model S similarly plagued by a low efficiency charger system as is my Roadster?"
When Tesla designed the Roadster, being their first car and with no real-world experience, they chose to sacrifice charging efficiency in order to err on the side of protecting the battery's health and safety. Therefore, I'm not surprised that it isn't optimally efficient. The Model T didn't exactly live up to modern efficiency, emissions, safety, . . . standards either.
I wouldn't necessarily expect that Tesla would spend too much time worrying about Model S charging efficiency either as, IMHO, they should be focusing on reliability and manufacturing cost reduction so that they can get to the point where they can make their affordable automobile.
Only after they get affordability under control do I believe they should start working on improving charging efficiency. They only have so much money to spend and I think it is best spent on business before satisfying us efficiency geeks.

· Bill Howland (not verified) · 5 years ago

@ex-EV1 driver

I hear what your saying, but for everything that GM has gotten wrong over the years, charging the Volt seems to be one of the few things they've gotten right. I could nitpick about only charging at 14 amps, but at least it is economical to do so. Another plus I havent seen mentioned anywhere is the Volt's electronics are basically convection cooled. (I'm not referring to the battery, just to anticipate objections). The Tesla, while I love it, is sorely lacking here, and, excuse me, really would have been designed differently if their project manager was a different person. A lot of this is personal preference, but I'm guessing a much older, experienced leader would have come up with a much less fussy and trouble-free system much more similar to the Volt's. The Tesla needs to be cleaned every year for $600 plus 9% due to having a stupid blower blowing road dust in clogging up all the heat sinks in the inverter module. I sensed trouble years ago that Tesla had an inexperienced team, at least in the 'project manager' category when they kept saying 50 amp outlets are typical of American Electric Dryers. They could have asked for confirmation from ANY electrician to find out they were horribly mistaken. I bought the car knowing that some of that ignorance was going to be filtered into the car. Another temporary blow to Tesla's technology was several of their better engineers died a few years ago in an airborne crash. And the Roadster does have a design defect in this area, in that during the preliminary charging connection, the system throws a 7 milliampere ground fault on the system, tripping Schneider Electric and other brand's chargers. Legrand's (Pass and Seymour) charger won't work either, although for another unknown to me reason. This is the fault of the dopey SAE J1772 standard, in that its not really in practice a standard at all, but thats for another day.

Economy is important, since lifecycle ownership cost is a very important marketing tool, as can be seen that electric car sales tend to be proportional to gas price rises. Its one thing to say, "the technology still needs to be developed", but, I'd say to that, "if a Chevy can do it, why can't a Tesla?".

· · 5 years ago

@Bill Howland,
Overall, I agree with you but want to point out a few things:
1) You undoubtedly have a 2.X Roadster. Even it is a huge improvement over the 1.5, especially in the PEM cooling. The Model S is completely different, with a liquid cooled PEM for more reliable hot-weather operation. Are the Volts power electronic circuits convection or liquid cooled?
2) The $600 annual checkup isn't just for blowing off the PEM. It is actually a chance for Tesla to do a quality check on their products over their life. They tear apart the car and check everything. The PEM blowdown is the only real maintenance that is done. We had a big argument with Musk in the early days about the pricing. He originally wanted to charge the customer for the labor that it actually costs Tesla to do the check and make a good profit as well. Their pricing over $1K was typical for a Ferrari or high-end Porsche. Following complaints by owners for being milked and ruining their arguments that they bought EVs for less maintenance costs, they dropped the price to their labor cost only. They reminded some Roadster owners that they were not just buying a car but they were supporting the growth of the company. The agreement was to charge cost since we also get the peace of mind that our cars are doing ok even if there isn't any real maintenance being done.
3) Not sure why 50 amp -vs- 30 -vs 70 matters. The beauty is that Tesla handles whatever current you have available.
4) The ground issues can be a pain, however, I know that Tesla set their safeties very high to avoid bad press that could deal a deadly blows to them and EVs in general. Their first generation High Power Charging stations actually included a smoke alarm to cut power if smoke was detected - just to be safe. Not being able to use some fly-by-night after-market product is one thing but possibly killing someone is a different one.
5) Tesla lost some good folks in that plane crash. The ones in the plane were well above the industry average but were certainly not critical to Tesla's success. They had hundreds more just as good. Be careful what you read in the press. They are usually pretty quick to declare Tesla dead at the slightest hint of adversity.
6) The "standards" problems you mention are one of the reasons Tesla went with their own technology. IMHO, the technology is not mature enough to standardize and J1772 definitely leaves a lot to be desired. They didn't do badly considering that most on the SAE committee work for companies that don't want EVs in the first place.
7) If you can't understand "if a Chevy can do it, why can't a Tesla?" , I recommend you step back a bit. How does 100 years and millions of products appear compared to 5 years and hundreds of products delivered? Tesla definitely is a startup. Apple -vs- IBM if you remember those days. Apple, however, has made a lot more money and happy personal computer customers than IBM. We may see Tesla jump way past GM. I'm not going to suggest that in 25 years that GM will no longer make personal computers but Tesla will be a leader but who knows?

· Bill Howland (not verified) · 5 years ago

@ex-ev1 owner

Well, hum, factual stuff first: Volt is convection as mentioned in my post.
50 vs 30 matters in that people who talk about "american homes" should have at a least a rudimentary idea of whats in them. Some things are just inscrutable, for instance Jay Leno, while having a great garage show, keeps saying your typical refrigerator runs on 220. He's been in Beverly Hills for too long, Most of the under $5000 sub zeros are still 110, and nobody in this part of NY state has anything more expensive than that.

You're giving Tesla too much credit here. Tesla told me they DID NOT go with J1772 simply because although it had been around for over 10 years, the version at the time was limited to 30 amps, and they wanted 70. I would have waited. The public stations around here are 30 amps max, and the Tesla reverts to 20, 15, or 10 amps if it gets hot outside anyway. They did not know of any problem with J1772 prior to me bringing it to their attention personally. I'm still cutting new ground in this area as I'm sure that they didn't know there was a compatibility problem with the Legrand unit.

Grounding is not a problem, the fact that the Roadster causes an unintentional ground fault is a design defect which Tesla does not deny. Their warranty specifically does not cover their own designed in defects, so their legal dept anticipated this kind of thing.

With that out of the way, subjectively, some things that are experienced are things that I wouldn't have allowed if I had any authority/say-so on the design team. I've designed things in the past, and shy away from troublesome/maintenance intensive/fussy/ solutions. But that's just me on my soapbox. I give credit where its due. GM usually admittedly comes up with lousy designs, but in my opinion, I like the volt's inverter system, and I think it should be considered a minimum standard. People who disagree with me, well, we'll just have to agree to disagree. I'm just callling 'em as I see 'em.

· · 5 years ago

I'm glad you've got inside info on the Volt. I'm not sure I agree with your Tesla info though. Have you seen the 10 year old J1772? It is also called Avcon and there are quite a few public stations in CA. The connector is quite big and bulky although I'll agree that there are a couple of nice things about them. I use them with my Roadster's UMC occasionally although many aren't working very well after over a decade of non-use. I heard this story independently from several key Tesla folks at their initial unveiling of the Roadster back in 2006.
I have a 70 Amp J1772 in my driveway and there are several public ones in CA as well. They certainly make roadtrips faster. It is now quite feasible to drive from LA to SF or Las Vegas. I just hope upstate NY gets them for your benefit. Having lived in that region for about 5 years, I can see how they would be useful.
I'm glad GM came up with a good inverter design. Now if we can just get them to let go of their transmission and maybe the could get on the road to an affordable PHEV.
I think you're a bit pessimistic about the Roadster's charging speed. I've only seen it current limit when the ambient temperatures were well over 100 F. I've seen it completely stop as well at over 115 degrees but there is a little trick to keep it going. Open the boot to get better air circ and park toward the sun. The boot lid will shield the PEM and battery. You can also wipe down the top of the PEM with a moist cloth to cool it and increase charging speeds as well. I've used these techniques in Las Vegas, NV and Barstow, CA.

· Bill Howland (not verified) · 5 years ago

@ex-ev1 driver

Thanks for the tips. I apparently only have to put up with it for about exactly 2 weeks, since this is the very hottest time of the year around here.. I've never seen it stop charging completely, unless it was very cold, and then the 2500 watt heater comes on to warm up the battery for 45 minutes or so.
Agreed, I don't like the J1772 standard, I can't believe the number of people and organizations working on it could come up with such a PPPPPP (thats Plainly Pretty Piss Poor Prior Planning) "standard". Be that as it may, it was a standard, and I would have accepted it to avoid having so many different mongrel plugs, and to ensure compatibility with whatever the homeowner had. But perhaps it is SO lousy that many manufacturers stuff won't work. Wattstations blowing out Nissan Leafs as an example. This merely shows there is certainly incompetence elsewhere. Its uncanny that a simple job of transferring single phase 60hz juice 20 feet could have so much trouble. As Ive said elsewhere, I'm glad these big experts didn't design Plugs for Tv's, Ranges, Ovens, Electric Dryers, and Hot Tubs. Then Nothing in the whole house would work. Many commenters, not just me, have mentioned what a bonanza charging dock manufacturers are having with the HUGE markup on them. I'm just pissed off it got written into NFPA 70 (the National Electric Code), but then, its similar to all the houses being burned down in the 60's and 70's with aluminum romex. I'm not saying the NEC wanted the homes to burn down, but there was collusion just the same. Lately I've read in the 'home' section of the newspaper that one "expert" has said the only real solution for these homes is to GUT THE ENTIRE HOUSE (!!!), and start over. Bulldozers anyone?

· · 5 years ago

@Bill Howland,
I agree with your complaints about the NEC and the poor standards, however, I see most of this as simply the necessary learning curve that any disruptive technology must go through in its infancy. In my professional career, despite trying to avoid it, I've spent a lot of time working with (or around) standards and interoperability.
Unfortunately, standardization never seems to be as easy as just writing down a specification and everyone follows it. The devil is always in the details and, if written before significant real-world testing is completed, often the specification may not even be the right solution to the problem. Standards development involves a lot of expense, traveling, meetings, document writing and review, email threads telecons, etc and often moves at a glacial pace. Standards developed quickly usually end up being useless and end up getting replaced or updated, often with minimal backward compatibility, leading to a lot of wasted money by early adopters.
Remember that with nearly all standardized things (cellular phones, personal computers and interfaces, media formats, document formats, side of the road to drive on, human language, liquid fuel type, grid voltages and phases, etc), there is seldom (if ever) one perfect standard that all agree on and works perfectly for everything. We see proprietary standards that are occasionally opened up to the public, standards driven by public standards bodies composed of competitors, and government led standards development. The bottom-up developed proprietary standards usually work better and can be deployed quicker, however, they are usually more expensive and can't be supported my multiple manufacturers. Ones developed top-down my standards bodies usually work best if there are working proprietary standards from which to base them.
I guess the upshot of this rant is that this is not an easy process and there are pros and cons to everything but I figure there is no sense grousing about it too much this early on. I have a set of adapters I can carry in my Tesla that allows me to connect to nearly anything. This is definitely a hassle (especially given the Roadster's small trunk) and even then, there are times when things don't work.
The last major disruptive technology I worked with from its genesis to wide scale deployment was cellular phones. It took over 30 years to reach a maturity level where one could take an affordable cellular phone and expect to usually be able to be reached in nearly any urban or suburban region of the world (although that can still be ghastly expensive). There are, of course, still exceptions to that rule as there still exist at least 2 major, incompatible standards in the world (one proprietary, the other originating from a standards body). Over a dozen grew, were deployed by the millions, and died without any remaining trace of their existence.
EVs and EV charging will undoubtedly follow a similar path of fits and starts with successes and failures along the way. J1772 may thrive, morph, or eventually become extinct, just as the old legacy AVCON, LPI, SPI, and Yazaki have. We can be pretty sure that the Tesla Roadster's charging standard will become extinct but I believe it was highly successful at helping to open the way for others, just as AVCON, LPI, and SPI were before it. Compared to installing a new charging station, it is relatively very cheap and easy to swap out an old legacy charger for a new one. We've seen this in CA and, while still a long way from being useful or convenient, it is definitely getting better. Folks who go with the old companies new to EVs like Schneider, Diebold (PEP), and GE who are trying to blast their way into a market they've ignored for decades will occasionally waste some money. I have experienced early incompatibilities and problems with pioneers like Clipper-Creek, AeroVironment and Etec (Blink) as well as newcomer startup Coulomb. Some required firmware upgrades (in the cars and the chargers) to fix as well.
Its not perfect but it is ok and improving.

· Jim Bullis, Miastrada Company (not verified) · 5 years ago

We recently began testing an electric vehicle that makes sense, even without the fake MPGE definition.


· Bill Howland (not verified) · 5 years ago

@ex-EV1 Driver

Ok, but in the time you took to write that post, I installed a switch to fix my Schneider Electric Incompatibility problem... Schneider Electric's engineer was at the same time A). So horrified I would knock his design, and B). So disinterested in my successful fix that he hung up on me after being forced to call me as a "humble pie" effort by Square - D's northeastern distributor. They still don't know what I did to fix their design, but if their next model included a 25 cent spst dip switch they'd solve the problem.

And by the way, you can't really trust many people anymore. I've written several reviews for Home Depot, all of which meet their 'publishing guidelines' and see they follow this general rubric: If the review is positive they'll publish it. If not, they won't.
Lowe's was better in this regard, but seeing as all these companies only copy their competitors bad ideas alone, I'm not sure they're still on the up and up either. Lowe's used to be honest in the distant past. Unknown now.

· Anonymous (not verified) · 5 years ago

This should not surprise any of you. I think it is amazing that model S gets numbers close to other EV's when in reality it has 1000 pounds of weight over most others.

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