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MF: Would half a million Teslas crash the power grid?

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Another link-baiting, FUDish headline from Motley Fool. :rolleyes: Of course I did take the bait and read the article, which was fairly interesting:

Would Half a Million Teslas Crash the Power Grid? (TSLA)


I want to bring this up though:

Our nation's electrical infrastructure is vastly underutilized. It is designed to meet peak demand and therefore runs at full capacity for only about 5% of the year. The rest of the time it could generate enough power to supply the energy requirements of 73% of the nation's cars, pickup trucks, vans and SUVs, according to a 2007 study by the Federal Energy Regulatory Commission (click here to review the findings -- opens a PDF). That's upwards of 200 million vehicles, meaning we could conceivably displace 6.5 million barrels of oil equivalent per day, or more than half of our nation's oil imports.

It sounds like the current electric grid could support hundreds of millions of electric vehicles in it's current state. I know that EV's are mostly charged at night, but what if a large number were charged during peak usage hours? Could we adopt mass scale solar charging for electric vehicles, for work and home, at the same timescale?
 
Technically half a million Teslas could crash the grid, if they all plugged in at the same time, in the same area of the network, at a time when that area was very stressed, of course, if everyone turns their oven on in the same situation the grid would crash as well.
 
Another link-baiting, FUDish headline from Motley Fool. :rolleyes: Of course I did take the bait and read the article, which was fairly interesting:

Would Half a Million Teslas Crash the Power Grid? (TSLA)


I want to bring this up though:



It sounds like the current electric grid could support hundreds of millions of electric vehicles in it's current state. I know that EV's are mostly charged at night, but what if a large number were charged during peak usage hours? Could we adopt mass scale solar charging for electric vehicles, for work and home, at the same timescale?

The quote is a bit wrong though. The grid has a lot of reserve capacity, if timed correctly which is the case with EVs in general anyway (they charge at night, when the grid is under a lot less stress). However, the grid does not generate power, it merely distributes the power. So the sentence "The rest of the time it could generate enough power to supply the energy requirements of 73% of the nation's cars, pickup trucks, vans and SUVs..." is all wrong, it should read "The rest of the time it could distribute enoug power to...". Generation capacity would have to be increased.
 
The quote is a bit wrong though. The grid has a lot of reserve capacity, if timed correctly which is the case with EVs in general anyway (they charge at night, when the grid is under a lot less stress). However, the grid does not generate power, it merely distributes the power. So the sentence "The rest of the time it could generate enough power to supply the energy requirements of 73% of the nation's cars, pickup trucks, vans and SUVs..." is all wrong, it should read "The rest of the time it could distribute enoug power to...". Generation capacity would have to be increased.

Perhaps "capacity replacement" would be more correct. EVs charge mainly at night. This means base load generation could be increased and peakers reduced--a win for everyone.
 
Technically half a million Teslas could crash the grid, if they all plugged in at the same time, in the same area of the network, at a time when that area was very stressed, of course, if everyone turns their oven on in the same situation the grid would crash as well.

A similar result could probably be achieved if the entire population of an area were to turn on all electric stove elements, turn up the heat on all electric heaters and run the hot water, crank up the air conditioning, turn on all their lights and electric clothes dryers at the same time (and is similarly improbable).

As a practical matter, the use of time-of-day pricing is the simplest and most direct measure to ensure that most Teslas won't take power off the grid during peak hours.
 
It's been said that if 100% of the cars in the US were electric it would only be a blip. Of course that will take 20 to 30 years so there is plenty of time to prepare.

Generation is not a problem. The uses about 4 to 4.1 trillion kWh per year. Generation capacity exists to generate 9.2 trillion kWh.
According to my calculations from this thread: Solar dream it would take about 1 trillion kWh to provide juice for all passenger vehicle driving ( 3 trillion miles worth ) - a 25% increase.
There is enough additional coal generation capacity to generate 1 trillion kWh, enough oil burning capacity to generate 420 billion kWh, enough NG capacity for another 2.6 trillion kWh. Nuclear, wind, hydro, solar, biomass and geothermal are all close to fully utilized but they could kick in a couple hundred billion kWh. ( Data here: SAS Output and Enerdat )
Just in the last 5 years we have reduced our coal generated electricity used per year by 500 billion kWh ( from 2007 to 2012 ) we could turn a lot of that back on if we were out of options - but we have time to add clean generation capacity instead.
 
What's needed is a lot more smarts between major energy users and the grid operators. (Here, I'll use the term "grid" to mean "bulk power system," including both generation and transmission; throughout most of the OECD, operations of these two sectors are closely synched.) This has been the goal of "smart grid" upgrades, but Model Ss in particular should be much savvier than they are currently about power consumption. Our cars are already linked to the Internet, so the car can both receive information about the state of the power grid (e.g. current and projected locational power prices) and send information about itself (e.g. current and target charge state).

There are, roughly speaking, two categories of "how to crash the power grid": something bad happens (e.g. a transmission transformer blows), or there's a longer timescale mismatch of load and generation (e.g. the weather guys screwed up and missed the heat index forecast badly). Putting some intelligence on EVs could certainly help with the first problem: it's no big deal, generally, to interrupt charging your car for 10 minutes while the grid operator gets primary reserve levels restored. Intelligent charging software would also help on the second front if the car "knew" that it can defer charging a few hours and still have enough charge by the time the owner plans to drive.

In an EV like the MS, with a massive battery, charging mid-day (when these longer-term load/generation mismatches almost invariably occur) should be a rare event. It's all the little Leafs and such that don't have much charging flexibility and so represent a potentially greater issue for grid operations.
 
What's needed is a lot more smarts between major energy users and the grid operators. ..........

......and I would add, between EV's the EVSE and the grid. In Calfornia we are seeing smart meters and I am beginning to see some EVSE's coming with ability to communicate to smart meters, and hence the grid. As others have said, we have the capacity, we have to be careful to not mismanage it.
 
That was my thinking. He says the grid will only be there for backup, but even with everyone having a system that produces as much power as they need everyday (extremely unlikely), they'd still need the grid everyday. If you want your own storage, to keep you're lights on 99% of the time (poor performance by grid standards actually), you'd need your storage to be extremely oversized as well as your system. These systems are only as cheap as they are because you can benefit from the grid at the grid's expense.
 
.............These systems are only as cheap as they are because you can benefit from the grid at the grid's expense.

How is the grid suffering if I am a net generator during the day and drawdown at night during off peak. In California my annual true up with SCE is at wholesale. That is $0.04 per kWhr. Pretty cheap power for them. I do own my system.
 
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How is the grid suffering if I am a net generator during the day and drawdown at night during off peak. In California my annual true up with SCE is at wholesale. That is $0.04 per kWhr. Pretty cheap power for them. I do own my system.

In that situation, you're helping the grid not hurting. At least until the point where you and all your neighbors are doing exactly the same thing, and then your utility will have to be concerned about the distribution lines and transformers in your area.
 
Well, it is not likely that the 30,000 people in this one sguare mile beach town in California will all be doing the exact same thing. Too many distinct individuals here. I do know at least four of us that are on solar and have electric cars. We all charge our cars at different times.
EDIT Come to think of it I have see a few Teslas and a bunch of Gems. EV's get free parking downtown.

Regarding the grid, doesn't my utility's rate include upgrading wires and transformers? At least that is what they told the Public Utililities Commission when rates were raised.
 
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Regarding the grid, doesn't my utility's rate include upgrading wires and transformers? At least that is what they told the Public Utililities Commission when rates were raised.
Yes, SCE will spend what it has to keep reliable distribution service and set its tariffs to collect the costs. This investment is exactly how utilities earn a profit for their shareholders, because their allowed rate of return exceeds their weighted cost of capital. Anyway, I digress...

The problem in your particular case arises because you mostly don't pay the wires charges. You (and everyone else with rooftop solar in California) only pay your portion of the wires charges on the net energy you use each month. This is akin to paying a toll to cross the Golden Gate Bridge, but then having it refunded as long as you drive back within the same month. You use the distribution network to sell power during the day, and buy power during the night, but if you manage your energy use to be in perfect balance during the month, you'll pay exactly $0 towards the upkeep of the network.

This "net metering" is not, of course, sustainable. What's happening is that SCE has to increase the distribution rate (which you just saw happen), which makes rooftop solar more attractive, which leads to fewer people paying for the network and higher rates; rinse and repeat.

SCE needs to change how it assesses the network charge and the prices it pays and charges for power. The simplest approach would be to have a flat monthly wires charge based on the amperage of your service interconnect -- a pretty good gauge of the capital cost SCE has invested to serve your house. As for your power, SCE should have to pay you 110% of the current real-time spot market price of power, as set by the California Independent System Operator. (The extra 10% comes from the reduced losses associated with getting power injected directly into the distribution system.) Figuring out the price you should pay for energy is a bit trickier, because SCE has all sorts of contracts that they're (properly) allowed to recover in rates.

So, to bring this back to the OP, if everyone's paying a fair price to use the grid, there's no problem loading more EVs onto the US power system. It would help, though, if utilities were providing better information (and prices) to help guide when people are charging, and likewise if the cars would automatically use that information to intelligently charge.