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XXXXXXXXXXX1
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join:2006-01-11
Beverly Hills, CA

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XXXXXXXXXXX1

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[CT] Vehicle fuel choice: Electric vs Gasoline

I've been toying with the idea of an electric car. Tesla is really changing many of the old rules of what an electric vehicle is and isn't, and the Nissan Leaf also offers some of the benefits of electric cars. But for the purposes of this thread, I'm interested in comparing fuel costs, not compare cars per se.

We all know that CT has some of the highest electricity rates in the country. I'm rate locked with Dominion at .0799/kWh for 2014 (plus delivery costs). I think the total cost is about .17/kWh (please correct me if I'm wrong). That being said, gasoline at $3.50-$4/gal ain't cheap. Let's assume for a moment I bought a Tesla and installed a charging station in my garage.

Tesla uses the following to compare electricity to gas (there is a calculator on that page): »www.teslamotors.com/goel ··· #savings

If we assume a gas sedan getting 22 mpg at $3.60/gal, total cost for 10K miles would be $1,636/yr. The Tesla at $0.17 kWh for the same 10K miles would cost $481.

Given the upfront cost of the Tesla is VERY expensive, but the fuel and ownership costs are lower (it doesn't need maintenance like a traditional car), it still seems the high cost of electricity in CT makes it an uneconomical choice.

Am I thinking of this correctly? Does the cost savings of using electricity in CT still outweigh the cost of gasoline fuel? I would probably drive 10K-12K miles per year, give or take. Some areas of the country with lower electricity costs probably make the numbers work.. but here in CT, I can't seem to find enough savings to justify it. Any thoughts?

geek
Mad Scientist at Work
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join:2002-01-07
Southbury, CT
TP-Link Archer C7

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geek

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Tesla is supposedly coming out with a new model next year for about 40k. I imagine that will sell like hot cakes. For now though I think you are right about it not making economic sense.
»www.siliconbeat.com/2013 ··· e-model/

Oh and your numbers look correct.
bennor
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join:2006-07-22
New Haven, CT

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The Tesla, Prius and other gas/hybrid/all electric cars still need maintenance. Brakes, tires, fluids, etc. The problem with electrics is the cost of battery replacement. Its not something most people figure in when looking at them.

In the grand scheme of things your simply moving the costs from the back end (gasoline) to the front end (manufacturing).
XXXXXXXXXXX1
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join:2006-01-11
Beverly Hills, CA

XXXXXXXXXXX1

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My understanding is that the Tesla cars have only one fluid to maintain (windshield washer fluid) and the consumables are brakes, tires and wiper blades, with the regenerative brakes needing replacement between 100K-150K miles.

Otherwise, the Tesla is maintenance free. I do agree there is a shift from after-sale gasoline to before-sale manufacturing. The math still may work in Tesla's favor.

vaxvms
ferroequine fan
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join:2005-03-01
Polar Park

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Check out this MIT Tech Review article
Electric Vehicles Out in the Cold

Cold weather presents two main challenges for electric vehicles: cold air limits battery performance, and running the heater drains the battery. As temperatures go below freezing, some drivers accustomed to traveling 250 miles on a single charge have seen their car’s range drop to 180 miles. Drivers in extreme climates might see the range decrease even more. That might force drivers to choose cars with bigger batteries than they would need in the summer, adding $10,000 or more to the cost of the cars.
XXXXXXXXXXX1
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join:2006-01-11
Beverly Hills, CA

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I heard that too. If Tesla come in at around 35K, I think the math really begins to work with fuel savings.
XXXXXXXXXXX1

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Thanks! Anonuser in the Auto forum has confirmed that with his Model S. Battery life has gone down dramatically in his cold Wisconsin winter environment. It is something to consider.

Interestingly, CT has Tesla Superchargers, and RI has just opened its first, but none in MA! Surprising that MA hasn't gotten any of these yet.
bennor
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join:2006-07-22
New Haven, CT

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Tesla apparently recommends performing service on (some or all?) their vehicles once a year or 12,500 miles. The service supposedly runs about $600.
»www.edmunds.com/tesla/mo ··· ney.html

For some their gas powered car will only need a yearly or bi yearly oil change (free or less than $50 in most cases), with a more expensive service every two or three years depending on how many miles they put on their car.

About the only way an all electric car will be cheaper over the long run is if one's electric rates are very low. Here in CT that probably isn't going to be the case. But hey if one has the money to burn and wants to buy it good for them.
pandora
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join:2001-06-01
Outland

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I used the Tesla link in your post, and noted no decline when using the heater or when driving in colder weather on the reported "savings". Same for the city vs highway driving selector.

I entered $1 per gallon and $1 per KWh to understand the numbers they are using. For 10,000 miles per year, at 20 MPG, Tesla correctly determines I'd spend $500 (I understand this isn't the cost, but it lets me easily verify Tesla is correctly computing MPG for gas engines).

For electricity, the number becomes 2,830 (which isn't meaningful as a dollar amount, BUT tells me exactly how many KWh Tesla says I'll use to drive 10,000 miles).

Tesla is claiming 3.5 miles per KWh of electricity it is charged with. Tesla's savings do not change with temperature, car load, type of driving, use of a heater, headlights or electronics. All of which seems odd to me.

I want to see how Tesla's energy efficiency compares to gasoline. Over here - »en.wikipedia.org/wiki/Ga ··· uivalent a claim is made that one gallon of "average" gasoline (varies by region and time of year) is about 34 KWh of power.

Tesla claims to get 3.5 miles per KWh. I multiply 3.5 times 34 (the KWh in a gallon of gasoline) and Tesla is claiming to get a gasoline equivalent of about 120 miles per gallon regardless of driving conditions or load.

Their vehicle will have inertia, and not all inertia can be recovered when stopping, likely most can't. The vehicle will experience wind drag, and must have friction (friction is required on tires to attain acceleration and to control a vehicle, it permits for example steering ... it is often referred to as rolling resistance).

The NHTSA has a longish report on tire efficiency, which includes a lot of information about vehicle efficiency as well at »www.nhtsa.gov/DOT/NHTSA/ ··· /Vehicle Research & Test Center (VRTC)/ca/Tires/811154.pdf per the energy loss diagram on pdf page 18 of the report a typical vehicle loses 18% of it's energy when idle, 2.2% for accessories, 5.6 is lost in the drive train, 62.4% is lost due to engine inefficiency, 2.4 percent due to air drag, and 4.2% to rolling resistance.

Of the factors above, 62.4% of the loss is from the engine, 5.6 is lost due to drive train, and 18% lost due to engine idle.

Assuming Tesla is 100% energy efficient at moving your power from the cord to the tires (no engine or drive train issues) a Tesla car could be 75% more energy efficient than a gasoline car per the report cited above.

Tesla is claiming 120 MPG effective mileage. Assuming 3/4 of the energy would be wasted by an internal combustion engine, a similar gasoline powered vehicle would produce 30 MPG (1/4 the MPG claimed by Tesla).

The Tesla weighs 4,647 lbs empty (curb weight) per - »www.teslamotors.com/models/specs ... when I visit Automobile Magazine, and want to compare the Tesla to similar vehicles. I get a list (which I hope is included properly in this link, if not my apology in advance) - »vehicles.automobilemag.c ··· are.html

Comparable cars seem to be Porsche Panamera S Hybrid, Audi S4 and Aston Martin Rapide. The Tesla is well priced within this group. It isn't the heaviest (the Porsche is).

However, MPG doesn't seem to match up exactly. Assuming 30 MPG using the conversions above is reasonable, then only the Audi comes close with a highway MPG of 28, but a city MPG of 18. The vehicle in the group with the closes overall MPG highway vs city is the Porsche which claims 24 MPG highway and 20 MPG city.

After factoring out for engine, drive train, and idle energy losses, Tesla is claiming a higher effective MPG than any comparable vehicle.

The mileage claim of Tesla, even after discounting for energy efficiency claims, seems a bit of a stretch to me. Though that is just my opinion.
scross
join:2002-09-13
USA

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said by XXXXXXXXXXX1:

My understanding is that the Tesla cars have only one fluid to maintain (windshield washer fluid)

When I test drove a Leaf a few years back, I was surprised to find that it had a radiator and cooling system just like any other car out there. I was told that this was to provide cooling to the electric motors. I was also surprised to find that it had a battery in the engine compartment, in addition to the main battery pack. The installed battery was quite small, but I noted that the battery holder looked like it would accommodate a regular-size car battery, also.
scross

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said by XXXXXXXXXXX1:

I've been toying with the idea of an electric car.

If you check around you may find that you can rent an electric car for a few days or whatever, in order to live with one for a little while. It's my understanding that used electric cars are inexpensive, too - generally cheaper than regular used cars. Not sure why, though, and I haven't really looked into that yet.
XXXXXXXXXXX1
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Beverly Hills, CA

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VERY interesting post! I hadn't delved into the numbers as deeply as you have done, but it does give some great food for thought.

I would only add that personal driving habits and climate conditions make an apples to apples comparison amongst gasoline powered cars tough.. never mind throwing electricity into the mix. Jackrabbit starts and city driving can make calculations rough at best.

I am going to ponder. I like Tesla's planned Model X, but given CT's high cost for electricity, it's tough to make the case that it would break even in the long run. I tend to keep cars until they fall apart, so I take a long view of car ownership.

And in 10-15 years, there's the question of battery replacement cost and availability. I can't find info on how long TESLA will make replacement batteries available as technology marches on.
XXXXXXXXXXX1

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Good idea. I'm still at least 18 months away from upgrading a vehicle, so there is no rush. The Model X won't even ship until late 2014/early 2015. Let's see how things evolve over that time.

I know there is a new charging station (not a TESLA Supercharger) in New London that just opened. I have no idea where, nor what it costs, but I know I read in the paper recently CT wants electric car owners to be no more than 20 minutes away from a charging station.
scross
join:2002-09-13
USA

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said by XXXXXXXXXXX1:

I can't find info on how long TESLA will make replacement batteries available as technology marches on.

Tesla is wisely striking deals where their battery packs will be used in other places, like for solar installations and such. That should drive down per-unit costs as economies of scale kick in, plus help ensure that Tesla battery packs are around for the long haul. A healthy pack-rebuilding and/or Tesla-compatible industry should sprout up with time, too; maybe even a DIY market.

»www.businessweek.com/art ··· age-unit

As far as charging stations go, they SHOULD be working to ensure that you can at least partially recharge any electric vehicle at a Tesla station or a Leaf station or wherever such a charging station is available; maybe not for free, though. This would go a long way towards alleviating any worries about range anxiety. I know they were supposedly working on some standards here, but I don't remember the details.
XXXXXXXXXXX1
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Beverly Hills, CA

XXXXXXXXXXX1

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I've really been thinking about a Model X a lot lately, and have gone over the numbers again and again, but even though I love the concept, I can't make the numbers work on it.

Given CT's high electricity costs ($0.17/kWh), and my limited yearly driving (10,000-12,000 miles), the savings in fuel and maintenance costs over ten years doesn't even come close to the upfront cost of the Tesla. Then factor in sales tax, property (car) taxes on it every year, increased insurance costs, garage charging outlet installation, etc, and the gap grows wider and wider.

I think I'm going to look more closely at the Dodge Journey (my "control group" comparison vehicle). Even fully loaded, it could be had for around $35K. I have had good luck with Chrysler vehicles, and have a great relationship with a local Chrysler dealership. Weird to think I could buy 2-3 AWD Journeys for the cost of the Tesla. Maybe Tesla will start making SUVs at a much more affordable price range, but for now the Model X is just priced too high to consider given the competition. And that's a bummer.