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Blog Musk Says All Superchargers Being Coverted to Battery/Solar Power

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Tesla CEO Elon Musk says “almost all” Supercharger stations will eventually disconnect from the grid.

Musk made the comment on Twitter in response to a tweet pointing out that Superchargers utilize energy from traditional fossil fuels like coal.


Musk notes that all Superchargers are being converted to solar/battery power. Images released earlier this year alongside the announcement of a major Supercharger network expansion featured large solar carports, a glimpse of what to expect.

While Supercharger expansion is currently in full swing, Musk did not offer a timeline for those stations to disconnect from the grid.

 
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IMO no Supercharger will ever not have a grid connection. By all means, generate some or all of your own power and manage your demand using solar and batteries, but you're really leaving money on the table if you have any periods excess generation. Similarily, you leave yourself very exposed in times of shortfall. It's unrealistic to think that you would be able to keep this system in perfect balance, especially counting for seasonal changes in generation and demand.
 
My guess is that it is also to save on utility demand charges which could be quite high if you have a full station of cars all charging at the same time.

There are companies looking at grid connected battery storage solutions for L3 EV charging as well. This is to help reduce those peak demand charges, but also to allow a DCFC to be connected at a site that might not have adequate utility infrastructure to handle the demand. (visualize slowly filling a bucket with water, then later pouring it out quickly into another container -- battery storage would let you do the same with electricity).

I haven't done the math, but would imagine you'd need a fairly large array of panels to go completely off-grid with batteries at a Supercharger site.
 
Yes, there are. Rocklin, California is one example. I doubt there is enough solar to provide all the power needed for the superchargers, but there are definitely many panels.
Tejon ranch picture from google maps:

TejonSolar.png
 
Tejon ranch picture from google maps:

View attachment 230558

Back of the napkin here.

91 panels, probably 200W each (2012 technology), 18.2kW DC nameplate. Total generation of ~~25,000 kWh per year, or enough to charge ~430 Model S 75's from 10% to 80% at 90% efficiency, or just over one per day.

Tejon has also expanded from the six stalls to ten (just used them a few days ago, returning from the TOC Leadership Conference and Annual Meeting.
 
Just to pick a few numbers out of the air:

An 8 stall unit x 120kw output x 25% average occupancy x 30% average load will output about 1,700 kwh / day.

Assuming 8 hours/day insolation and sufficient batteries to carry across the full 25 hour period, that means that you'd need 216 kw of solar panels (output).

Assuming 200 watts/sqm, that means 1000 sqm of solar panels. Let's triple that 3000 to allow for less than ideal weather, and/or higher demand days. That's an area 55m x 55m. And if you assume an installed cost of $1 per watt (unrealistic now, but it will get better), that's three hundred K$. That doesn't sound implausible.

You'll always need a grid connection to deal with high peaks and long periods of bad weather, but a zero net draw over the course of a year is probably not out of line.
 
IMO no Supercharger will ever not have a grid connection. By all means, generate some or all of your own power and manage your demand using solar and batteries, but you're really leaving money on the table if you have any periods excess generation. Similarily, you leave yourself very exposed in times of shortfall. It's unrealistic to think that you would be able to keep this system in perfect balance, especially counting for seasonal changes in generation and demand.

Maybe they'll be able to put a supercharger in a small town or side of the highway somewhere that doesn't have the infrastructure so it'd have to be off grid.

Still anywhere the grid is sufficient to keep up with the load of even one stall it'd be nice to have the grid tie should weather be bad for a period that exceeds your battery backup. WK057 showed that even with what is considered by most an oversized array and tons of storage your demand can outlast your battery backup.
 
One thing we're not considering in Elon's usual "stretch" is the Tesla efforts in utility PowerPack sales. The Battery farm that was sold in Hawaii and to Southern California Edison could be powering superchargers (well at least the Edison one will be)....
 
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More back of the napkin math:
Say 8 hours average charging, 8 hours average sunlight a day*

If a panel is 300 watts and charge power is 90 kW, then 300 panels per stall for net zero. I'll leave necessary battery capacity for another calculation. I think it is great that Tesla intends to place PV and batteries at each SC but disconnection from the grid sounds hopelessly optimistic. This is more likely a plan to place PV nearby and call its generation an input. That is stretching the facts just a wee bit but more than good enough for me.

*Very optimistic, since it implies STC

As an aside, I find it really interesting to consider that as these battery enabled SCs proliferate they will become a Utility grid services provider in their own rights. It is a nice way to solve the power surcharges Tesla currently must absorb.
 
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Elon's "over time" statement is likely referring to a very long timeline. Probably a few decades. Imagine who cheap panels and Powerpacks will be in the future. And yes, some Superchargers will need to remain grid-connected because because location doesn't have enough insolation.

Elon's tweet, quote: "All Superchargers are being converted to solar/battery power. Over time, almost all will disconnect from the electricity grid."
 
I don't think "disconnect from the grid" was meant to be taken completely literally, as in physically severing any connection with the electrical grid. Rather, during the time that a given Supercharger is being powered 100% by PV+batteries, it'll be electrically "disconnected" from the grid. Tesla's goal is to have this be the case most of the time.
 
I don't think "disconnect from the grid" was meant to be taken completely literally, as in physically severing any connection with the electrical grid. Rather, during the time that a given Supercharger is being powered 100% by PV+batteries, it'll be electrically "disconnected" from the grid. Tesla's goal is to have this be the case most of the time.
This almost has to be the case. In much of the world, it is a common occurrence that there are cloudy skies during winter months, sometimes for days, weeks, months at a time (I've spent time in northern Europe). You will exhaust the batteries, no matter how robust, and no matter how many panels and how efficient they are.
 
I agree that completely disconnecting from the grid is unrealistic. But it's also important to note that the comment came in response to a gross misconception about coal and the electric grid: Modern coal plants, as bad as they are, are cleaner than gasoline automobiles. Even powered by coal, an EV is cleaner than a stinker. And coal is the dirtiest thing on the U.S. grid. The grid overall is much cleaner than coal and getting cleaner by the year. Opponents of electric transportation love to pretend that the U.S. power grid is coal, when in fact it's a mix of coal (in itself cleaner than gas cars) and a number of other sources which are even cleaner than coal. Where I live the grid is hydroelectric. And even electric utilities are installing solar and wind power to add to their energy mix.
 
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