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Comment by jws | Hacker News Reader

Cumulative total energy delivered to date: 4.9 million kWh

That works out to about $250,000, or about $10 per Tesla Model S sold to date. Early days and all, but it looks like about $100† tacked on to the selling price of the car covers lifetime supercharger network power use. Capital expenditures to build them probably dwarf their electric bills.

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† To the limits of Fermi Estimation

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I suspect the energy cost is a little higher than that because a commercial electricity customer (like Tesla) will often be subject to 'demand charges,' which are assessed based on the highest power used in a billing period. Since the point of a supercharger is to deliver a lot of power, the demand charge may be quite high.

I still agree with your conclusion though... Capital still dwarfs energy, even if they pay several times what you estimated.

I doubt that any individual super-charger station is a large enough load to be charged for their peak usage. It's a big load but nothing like a smelter or even a small factory.

Definitely more power than a small factory. A six station supercharger could be pulling 500 kW.

Up until 2012, demand charges from Souther California Edison kicked in at 20 kW at a rate of $17 per kW. One of the first 50 kW quick-chargers in LA county was shut down for months after the owner realized that operating it would tack on an extra $1000 to his monthly bill.

It's a $2000 upgrade fee to use the superchargers (on the 60kWh battery). The $2000 fee is included in the 85kWh battery model.

I didn't think that was correct but it does say that down in the 'How It Works' section. Its interesting how the skate over that one little detail.

Any battery has a hard time storing an amount of energy that costs the same as itself during its lifetime. This is opposite to combustion engines, which can pump infinite amounts of dollars through their cylinders.

It's an insanely smart offering.

IC engines are far from infinite. In fact, most can "only" burn in the neighborhood of 3-5K gallons of fuel per cylinder before requiring a major overhaul.

It's admittedly quite a bit more than the supercharger equivalent, but it's far from infinite.

Was curious, did the math: 3-5K gallons * 6 cyl * 25 mpg = 450,000 to 750,000 miles.

removed my incorrect math re: dollars of fuel per engine

3,000 gallons per cylinder * 6 cylinders * $4 per gallon = $72,000

5,000 gallons per cylinder * 6 cylinders * $4 per gallon = $120,000

Double-check your math: it's $4 per gallon, not $4 per mile.

If you're putting 5,000 gallons through each of six cylinders at $4 per gallon, that works out to $120,000 of gas. Certainly outweighs the cost of the engine by a decent factor.

whoops, thanks!

How did you pick your electricity cost?

It's a lot lower than I would guess.

$0.05/kwh. About what industrial users pay in most of the US.

I thought superchargers were solar powered?

That's for the future. Apropos, the source of power for electric cars is a frequent discussion issue among environmentalists. In some parts of the country, for example the Northwest, there's a lot of hydroelectric power, so an electric car is better for the environment than a gas-powered car. But in places where most of the power is generated using coal, it's not so clear-cut -- owning an electric car or a gas-powered car might have roughly equal effects on the environment.

Factor in nuclear-as-drop-in-replacement for coal, or future solar / wind generation capacity then purchasing an EV now still makes sense. Cars are on the road for 20+ years, new generation capacity is coming online constantly, so I think it makes sense for people to buy EVs.

EVs make sense for some people. But not most people. Not yet.

> But not most people. Not yet.

Out of curiosity, what do you think needs to change for them to make sense for most people?

I personally feel the Model S has made an enormous step towards "makes sense" for a lot of people, and I have to think the X will "make sense for most"

I guess one of the benefits is that you're decoupling the energy transfer method from the energy source. If there is new development of solar, wind, geothermal, wave energy etc. electric cars will be ready to receive energy from them versus trying to replace ICE cars. Even if the energy is derived from coal, cleaning the waste products at the factory is easier and is easier to upgrade the filters rather than replacing catalytic converters with better ones on regular cars.

Really? When I researched this last, even the worst power source charging a Tesla outpaced internal combustion pollution (at the point of power generation only, not counting the cost of making the batteries).

Keep in mind that what matters is not just the amount of power generation capacity, but the ability of that capacity to respond to demand.

Some background: The bulk electricity market (at least in NY state) is run as a giant linear programming problem to satisfy the demand for all regions with a set of supply curves that suppliers bid into the market. They all get paid the same price that the marginal watt (the last watt you need to buy to meet demand) costs.

So, natural gas turbines, who can turn on and off relatively quickly, will bid high and are likely to be the marginal watt. Nuclear plants bid very low and occasionally negative because it actually costs them money to shut down because they then can't start up again soon. So, they want to be sure that they are going to be scheduled.

This is oversimplified and ignores the difference between the day-ahead market and real-time market, products like regulation (we pay money for people to be ready to turn on/off and keep things at 60Hz), and inter-zone transmission)

The point is that a nuclear plant can't suddenly turn on in response to a spike in demand from quickly-charging car batteries. A bigass flywheel or a bigass battery (shameless plug for Sadoway: http://www.ambri.com/) might though.

One hell of a disparity between that and my parents paying ~$.18/kwh in rural Michigan.

Your rural parents don't make nearly the use of the physical wiring that cost so much to install. It shows in the rate.

That and slamming consumers is what the power companies do (here in New Zealand). See the commerce commission report (2009 - and there have been large price increases since) that found profits unreasonably high. http://www.comcom.govt.nz/dmsdocument/192

Also a kiwi here. Read the summary and it said the commission closed the investigation. Looks like every thing was legal, just the power companies maximising profits. Exactly what companies should do.

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