Southern California Edison White Paper Details Plug-in Vehicle Charging Habits, Grid Stability and So Much More


Southern California Edison (SCE) claims to serve up electricity to customers who “lease or own more than 12,000 plug-in electric vehicles (PEVs), both battery electric (BEVs, for about 35%) and plug-in hybrids (PHEVs, for about 65%),” according to Green Car Congress.

Basically, this means that SCE serves around 10% of all the plug-in vehicles sold in the US.  We’re guessing this makes SCE the largest plug-in vehicle electricity provider in the US, but don’t quote us on that one.

Regardless, SCE knows more than a thing or two when it comes to plug-in vehicles, owner charging habits and the impact of electrics on the grid.

SoCal Edison Sees No Immediate Threat to the Grid Coming From Influx of Plug-Ins

SoCal Edison Sees No Immediate Threat to the Grid Coming From Influx of Plug-Ins

SCE recently released a white paper titled, “Charged Up: Southern California Edison’s Key Learnings about Electric Vehicles, Our Customers and Grid Reliability” and in it there’s a wealth of information.

Below, we’ll highlight some of the key points, as outlined by Green Car Congress:

  • “SCE estimates that by 2020, there will be about 350,000 PEVs in its service territory.”
  • “Since 2010, of all the nearly 400 upgrades made to (or identified for) circuits that serve PEV customers, only 1% of that work was required due to additional power demands from PEVs.”
  • “Current data shows that about 50% of PHEV drivers in the SCE territory charge at Level I (120 volts), resulting in a much lower impact on grid distribution circuits than if more customers charged at Level 2 (240 volts). With 70% of SCE PEV owners commuting 40 miles or less daily, many PEV owners can fully recharge at night at Level 1; SCE encourages PEV customers to charge up every night at home.”

The only grid issue that SCE sees in the future is from the potential impact of multiple upcoming BEVs with 6.6 kW or higher on-board chargers.  SCE will monitor this situation to see how it impacts the grid.

SCE further says that anyone who may buy an electric vehicle soon should first contact their utility company, so that the utility can ensure adequate power distribution in your area.

Lastly, Ed Kjaer, an author of he SCE white paper, says this:

“A residential circuit handles something like 7-10 homes; adding a plug-in is like adding an extra home to the circuit. We’re finding a very low incidence of infrastructure upgrade required because of plug-ins. There is nothing like doing upfront preparation to ensure that things go according to plan. When we anticipated the cars were coming, we did a huge amount of work analyzing the circuits, and anticipated where we’d see clustering of the vehicles. We incorporated the load analysis into our overal daily infrastructure actions. We’ve got a very good handle on the increased load from transportation—that’s just being incorporated into daily activities as we upgrade the system. We obviously have a very good handle on the characteristics of those vehicles.”

Categories: Charging, General


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14 Comments on "Southern California Edison White Paper Details Plug-in Vehicle Charging Habits, Grid Stability and So Much More"

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That’s a pretty messed up graphic. It seems to say that EVERY SINGLE ONE of SCE’s customers drive a plugin vehicle. 35% of them drive BEVs, and 65% of them drive PHEVs. Pure gasoline and non-pluggable hybrids seem to have been completely removed from the SCE territory car market. That was fast! WOW!

This timely news article is likely to be drowned out by the recent ‘ad’ in the LA Times showing how, NO, SCE is not going to refund the $1/2 Billion they’ve wasted on an unbelievably dumb Steam Generator design (TWICE!), and NO, they are not going to refund money they’ve charged buying replacement power for the out-of-service Nuke plants, and NO, they aren’t going to refund money for the huge employee payroll they’ve supported during the time of the “up in the air outage”, but now that they’ve finally decided to decommission it, the $2 billion set aside is not enough and now they need another big rate increase!

Its a good thing there’s no more gasoline powered cars in their ad, because if such things really existed they’d be far cheaper to run the SCE’s (soon to be) most expensive in the nation electricity.

I think the fact that 50% of the people use level 1 for charging shows how it can be useful to make very small efficient EVs because such EVs do not require a 240V EVSE installation. If you can get 40 miles on an ordinary 110V outlet overnight, that is is often enough for people to commute with.

You can get more than 40 miles on L1 overnight. Some people arrive home at 7pm and leave at 7am, so 12 hours at 4-miles per hour would be very good even for a Leaf recharge of about 48-50 miles in 12-hours. The Teslarians will say otherwise, but a fleet of 100-mile BEVs using L1 or mild L2 charging would work for many commuters.

I would think that most “Teslarians” would be fine with overnight L1 as well. Just because they bought a car with a 200+ mile range doesn’t mean they use that range every day.

Except that the “TeslarianS” cars seem to get rather thirsty and sleepless in the freezing cold nights and a L1 charging may not even be able to sustain the battery charge.

L1 charging is also problematic because of the various conditions of the circuit wiring and the state of the outlet especially when mounted outside and used frequently. Another very important consideration is knowing the location of the circuit breaker should charging the car trip it and potentially kill the power to other devices. This is not feasible outside of people’s own homes.

If L1 charging is not enough to sustain a charge in a Tesla (even on freezing nights) then the Tesla has a serious design flaw.

Yes, when its cold outside, such as for the NY Times driver , the car draws 1840 watts. Figuring 1300 watts as a practical L1 charging limit, the car still loses range even though constantly plugged in. This is using Tesla’s own information.

Car owners on the Tesla forums report their batteries lose ~ 10 miles range after sitting 12 hours. Teslas may also use ~10 miles to warm the battery.

Should have explained, those #s are for vehicles not plugged in.

I commuted with a leaf on 110v for several weeks, no issue. In fact, after putting a l2 charger in at home the only real change has been that occasionally I charge during the day on weekends to get more range.

The #1 plug-in vehicle market, Southern California, has 7,800 plug in hybrids and 4,200 full EVs. Which is logical, since a plug-in hybrid can be the only vehicle in a household, and a full EV will normally be an additional vehicle. Which also means a duel EV household could be a plug-in hybrid and full EV household.

It also seems that SEC is clarifying once again that the best place to charge your EV is at home each night and leave the grid alone during the peek hours.

The article is framed by a current paradigm where cheap electricity is readily available at night, and with not much consideration of a carbon budget. This does raise the issue of renewable energy generation/availability/stability for the customer preferred night time recharge.

The article the other day about the need for recharging at work is part of the answer in demand shifting exploiting solar generated electricity. But will there be enough surplus wind generated electricity in these overnight hours so that highly valued despatchable hydro, bio fuel, & solar thermal storage generated electricity is minimised and not exhausted?

I’m discounting nukes in this as for much of the world these are totally unacceptable – human failings mean we can’t be trusted.

This is beyond the intent of the article, but its an important matter when we bang on about how easy it is to over night recharge EVs. In the big picture it might not be the best strategy.

Does SCE work with consumers for home storage solutions where they have solar PV?

Excellent point, but the truth is that cheap electricity will be readily available at night for quite a while as we ramp up renewables – at least for another decade or two. This article is definitely framed to address the near-term concern of increased usage of grid electricity for transportation, not the long-term end game. Just get the EVs on the road, and that can be sorted out later with shifts in time-of-use rates.