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Cost per mile to drive S versus comparable cost per mile with a gasoline equivalent?

Let's compare conventional gas cars and electric (S) cars in terms of dollars per mile (US), which is what the bulk of the world will care about.

Gas is about $4 US / gallon where I live. Say my car gets 20 miles / gallon. Ratio these and you get

$4 US / gallon
----------------- = $0.20 / mile = G <-- call it G for cost to drive per mile using gas
20 miles / gallon

What's the number for an S, measured as follows:

$X US / unit of charge
-------------------------- = $X/Y / mile = S <-- call it S for cost to drive per mile using electricity
Y miles / unit of charge

Is S > G or is S < G? In other words, does it cost more per mile to drive an S than my car (focusing on fuel only)? Or, is the reverse true? Is this information somewhere on the Tesla website? Where exactly?

Bryan

@Nicu:

I stand corrected concerning "scary smart".
It was Mycroft, in another thread, who wrote, " ... obviously haven't met someone who is scary smart."

Nicu,

Nor does a Ph.D. in a certain discipline (physics, chemistry, etc.) make you qualified in any specific area of that field. I had a friend after a summer job at a well known national lab (I don't remember which now) tell me how little the researchers remembered of physics outside their narrow area of expertise.

Although I took courses in plasma physics and nuclear physics while in grad. school I would in no way be qualified to work with the LPP or any other fusion project (even if younger and smarter).

Well, I did get my Ph.D. in '71 and it was in surface physics, so I wouldn't expect to qualify. Most of my post-doc experience has been in general college physics teaching.

At least their basic arithmetic is right. The mass defect associated with the proton-boron reaction does yield the energies they indicate.

Anyone out there considered a wind turbine for their home?

Andrew, depending on where you live, that could be an economic option. Solar is more popular because it has little maintenance, operates silently, and isn't very visible. Make sure your local zoning ordinances would allow you to install a wind turbine.

Robert-What about solar shingles?

Solar shingles attempt a between functionality and aesthetics. If you're looking for the cheapest solar alternative, go with panels, which have higher conversion efficiency and can be mounted in a direction and at an angle to maximize power generation. Assuming your house doesn't happen to have a roof perfectly aimed and slanted, the shingles will be somewhat less effective -- but they look a lot prettier!

As one analyst wrote, "building integrated solar installations are, despite manufacturers' claims, still significantly more expensive than conventional rack-mounted solar arrays due to increased costs associated with manufacturing and installation. The devices currently occupy niche markets for those willing to pay a premium for the aesthetic value of the less-obtrusive integrated systems." http://www.technologyreview.com/business/24383/

A good article is:
http://www.thisoldhouse.com/toh/article/0,,1205726,00.html

One trouble with solar shingles is that they are fundamentally still based on asphalt, which is basically the sludge left over after cracking a barrel of crude oil There are also more sustainable options, called Building Integrated Photovoltaics (BIPV). Instead of mounting PV panels over your existing (or new) asphalt roof, true PV cells are integrated in a sustainable design, such as manufactured slates or tiles. See http://www.igreenbuild.com/siteSpecific/vendor/vendorDetail.aspx?vendorI... and http://www.artezanos.com/tile_integrated_photovoltaic.html for examples.

I think it has already been established that recharging the foreseeable number of electric cars on the existing grid is not a problem. I have not seen any commentary on the coming mass market for LED lighting, which saves 80-90% of energy usage. EVs and LEDs are both poised to happen at the same time (huge potential but current high price being steadily reduced). They will work hand in hand to free up energy for the eventual total replacement of the vehicle fleet. Similar positive feedback loops exist for use of EV batteries for grid storage and the general load evening effect of flexible overnight EV charging. The future of EVs is bright!

One thing every one has to remember:

1 US Gallon = 3.785 liters

1 UK gallon = 4.55 liters

As of today:

1 gallon of US gasoline = $3.33 (as of today, 11,16/2011, MD, USA)

1 Kilowatt/hour = $0.136040146 (Inclusive of all charges, taxes, etc in Maryland)

Therefore:

($3.33 / $0.136040146) = 24.781 Kw/hrs

24.781 Kw/hrs * 1000 = 24781 watt/hrs

(24781 watt/hrs) / (300 watt/hrs/mile) = 82.6 miles

As in a ICE vs an EV engine, the bottom line will be dependent on tire pressure, road conditions, driving habits, and other factors.

[nitpick: it's kWh not kW/h]

Nice calculation. So Model S reaches 82.6mpg if calculated using dollars instead of efficiencies. I think that matters more.

Here in Europe that would be around 190mpg because gas costs so much more here.

Here in BC you can divide the power cost in half, and multiply the cost of gas by 1.5, so the S would get about 5/.07 = 70 kwh for the price of a USGal of gas, so 70 x 1000/300 = 233 mpg. Not tea bags!

It seems that this cost per mile calculation is proving itself a nice diversion. I can't help but notice that with gasoline costing just under $4 per US gallon in New York, and with my electricity much higher than most here are paying, that my New York equivalent mpg is worse than most are posting here.

We have a thread for reservations to simply track "how many".
We have a thread to see "where is your S going to be".

Now I think it would be interesting to see a geographical chart showing numbers reserved versus equivalent mpgs (MsPG?). Given the large showing New York has in reservations, it looks like this stat may be among the worst economic predictors for sales of a Model S.

Perhaps it will be a better predictor for BlueStar.

Sounds like you have cheaper gas than us Europeans, but also very cheap electricity. In here electricity costs about 10 cents EUR/kWh which translates to about 13.5 cents USD.

My electricity including taxes is up about $.20 per kWh. (Sorry, I don't have it to the nearest ten-millionth of a penny.) With gas at, say, $3.90 per gallon, my equivalent-mpg is 65.

I did this same calculation before reserving - I was happy that it was above 50.

If you're paying about $2/liter ($7.60/gallon) and $.135/kWh, yours would be 187.

Gas costs about 1.55 EUR/liter = 2.09 USD/liter (that's current average, variance between 1.41 and 1.64 EUR / liter).

187mpg is close, electricity from my supplier costs 8.94 Cent/kWh while average is near 10 Cents. (it's not quite that simple of course, there are different prices for nighttime, winter, depending of contract when it is measured, how much you actually use, which kind of source is used etc.etc.etc.)

@Timo: Thanks for pointing out my mistakes on the units
@EdG: I think your idea of a geographic map with equivalent mpg's is a good idea
@Brian H: Watch out that BC Hydro does not hijack rates to supplement BC government general funds! (grew up in New Westminster, BC)

I think all of us have to make the simple calculation to see if it is worth while economically in buying the Model S. It will vary greatly with each area but it also an individual choice to reduce each of our carbon footprints and move forward to decreasing our oil dependency.

Thank for the comments

Carbon footprints bah! Elon and the CO2 fear-mongers are deluded. It's the non-CO2/H2O combustion products that are an issue, if anything is.

EVs are good because they're efficient, quiet, fun, and inexpensive to run. As for power generation, without going techy, the world is awash in surplus natural gas, it turns out, and that's an efficient and dispatchable way to run power plants.

Agreed, Brian; savvy companies in the clean/green space have shifted from "global warming" to "energy security" as the rationale for change. "Stop buying oil from OPEC!" plays with more people than "Save the polar bears (unless it's already too late)!".

When carefully looking at the data for global warming, there is a strong correlation, but it's far from a proof.

The OPEC concept is clear, and recent history gives people even more 'energy' to change.

Just for fun, I used @b826166's cost analysis to build an equivalent mpg surface for varying gasoline and electricity costs.

Gasoline ranges from $3.40 to $5.00 per gal and electricity ranges from $0.05 to $0.25 per kwh. (I'm aware gas is much more expensive in the Europe, but this is a start)

Pick your local electricity rate on the horizontal and your cost of gas on the depth axis and you've got your equivalent mpg. Obviously, highest equivalents occur where electricity is really cheap and gas is really expensive.

For your amusement:

Brian H,

We do have a lot of natural gas in this country, and it stores well, and can be used for heat, transportation, or electricity. Grand stuff. The only problem is when fracking is used to get the gas. The chemicals are staring to be detected in ground water. Not good.

Here in Seattle, gas is pretty much 4 bucks, and I assume over the life of the car that's about as low as it's ever going to get. Electricity, even with the extra bit we pay for green energy is about 11 cents.

I'm a fierce advocate for nuclear fusion. We have a great fusion reactor up and running right now, and it's only 8 light minutes away from where you live. Operating costs are zero, virtualy unlimited capacity, has a great operating lifespan, and you can harness the energy directly as heat or photons, or indirectly through air convection.

Where and what is this reactor? I did not think it was fully functional yet.

EdG;
Except that the correlation works backwards: warmth first, CO2 later.

jbunn;
Chemicals in the water? I don't think so. Check your sources. The fracking is thousands of feet below the water table, and the drill pipes do not "leak". At the pressures employed, they'd virtually explode if cracked.
Every case of "gas in the water" has turned out to be a pre-existing condition. There's a full-court BS-press going on from the Greenistas to block cheap energy. Here's a classic quote:
"Giving society cheap, abundant energy would be the equivalent of giving an idiot child a machine gun.” — Prof. Paul Ehrlich, Stanford

Andrew;
8 light-minutes is the distance to the sun. jbunn is funnin' you.

Brian H,

It should come as no surprise that when you pump fluids in with enough pressure to fracture rock for thousands of feet in every direction, you just might drive trapped gas through those fractures. Up would be an ideal direction for a gas.

Here's a peer reviewed journal from the Proceedings of the National Acadamey of Sciences on "Methane contamination of drinking water accompanying gas-well drilling and hydraulic fracturing" April 14th, 2001.

The abstract starts; "Directional drilling and hydraulic-fracturing technologies are dramatically increasing natural-gas extraction. In aquifers overlying the Marcellus and Utica shale formations of northeastern Pennsylvania and upstate New York, we document systematic evidence for methane contamination of drinking water associated with shale-gas extraction. In active gas-extraction areas (one or more gas wells within 1 km), average and maximum methane concentrations in drinking-water wells increased with proximity to the nearest gas well..."

The article also states that the gas geochemistry matches the trapped gas found in the shale. The methane found in normal ground water far from the well has a signature showing it's of recent biological origin.

The rest is here... http://www.pnas.org/content/108/20/8172.abstract?sid=de10f21c-3762-480d-...

PNAS and organizations like the "Cary Institute of Ecosystem Studies" are desperate to block cheap energy.
Even PNAS published a number of responses, like this:
http://www.pnas.org/content/108/37/E664.extract
Hydraulic fracturing not responsible for methane migration

Samuel C. Schon1

Department of Geological Sciences, Brown University, Providence, RI 02912

Although Osborn et al. (1) provided important geochemical measurements of dissolved methane in a portion of the Appalachian basin, their report does not fully appreciate the geologic history of this region and misrepresents potential risks of modern drilling and completion techniques used to develop shale-gas resources. The fear that hydraulic fracturing is responsible for methane migration from the Marcellus shale into shallow groundwater is contrasted by direct observations in microseismic studies that even the longest fractures induced by the hydraulic fracturing …

Only the original article is free, of course. The responses are paywalled.

Sorry, challenging the National Academy of Sciences as a sop to the eco-extremists doesn't cut it. I don't know the answer, but I know the debate's not over.


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