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Discussion Starter · #1 ·
Currently the number of Level 2 stations outnumber Fast Charging stations. Just thinking out loud here, how useful are L2 stations set up a retail centers? If you plug in at a grocery store and stay for an hour, even two, your car has gained some range--but not very much.

Now, L2 stations at a place of employment--maybe a firm with 100+ employees--that does sound practical because EV owners can plug in for a few hours and gain substantial range. An important question would be how many other employees are EV owners who want access to the chargers.

L2 chargers at home (when possible) are great. I plug in my car after 7pm when our rates go down, and I'm all set because I rarely drive farther than half of my Bolt's range. All good.

I've been wondering about the U.S. Transportation Bill (hasn't passed but likely) and how they plan to increase the number of EV stations. What will actually get built? Hopefully they'll build stations with Fast Chargers, because that would be truly useful for people on long trips and EV owners who don't/can't have a charger at home (for example, tenants in apartment building).

Comments?
P.S., technical accuracy question: are "fast charging station" and "Level 3 station" interchangeable terms?
 

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You're going to get the full gamut of opinions on this.
 

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The places and needs vary widely. L1 would be fantastic in long term airport lots, even many workplaces. L2 at hotels, workplace, home, retail are very useful if not essential. L3 (DCFC) on long distance travel routes can't be beat, L2 is just not sufficient for this kind of location.

In other words, location, location, location and a time and place for all options.
 

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L2 EVSEs are infinitely more useful than DC (sometimes fast) chargers on vehicles that cannot be DC charged.

For the grocery store case w/DC chargers, problems can arise for people staying longer than is needed for their car to reach full.

I still need to start a thread that I wanted as I mentioned at Why do DCFC stations cost so much? if I or someone else hasn't already. Costs of the stations, electrical work and demand charges can be a huge issue.
 

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In MY mind, "Fast charging station" and "Level 3 station" and "DC Fast Charger" are all interchangeable. (Level 3 is not an official term AFAIK."

Seems to me that Level 2 is ideal at a workplace, because it allows people to charge their batteries while the sun is shining, when "green" energy is being generated. Charging at home generally means charging at night, which means either your energy provider had to provide battery storage, or fossil fuel generation, or (in my case) nuclear electricity generation.

IMHO, Level 2 chargers are also ideal at hotels, where people will be spending the night away from their home charger.
 

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I've been wondering about the U.S. Transportation Bill (hasn't passed but likely) and how they plan to increase the number of EV stations. What will actually get built?
CCS/SAE (DC Fast) stations from 150 kW and forward.

The details are difficult because of the wrangling going on and how it's all going to be paid for.
 

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IMHO, Level 2 chargers are also ideal at hotels, where people will be spending the night away from their home charger.
They are useful right now; however, it won't be too long before there are quite a few more EV on the road and hotels will have to install quite a few more of them than seems to be on their minds right now...or attract DC Fast providers to install close to their sites.
 

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Level 2 is appropriate for locations where people travel long distances and will spend several hours - hotels, theme parks, etc. It's also appropriate for locations where people spend several hours every day - home, work. I could even make the argument that it's appropriate for local places where people only spend an hour or so. Remember, most people only drive ~30 miles per day, so that's just a little over an hour of level 2 charging. Even level 2 charging at a restaurant or grocery store might work as a loyalty perk. After all, people will shop at a grocery store just to save a few cents on gas.

Edit:
They are useful right now; however, it won't be too long before there are quite a few more EV on the road and hotels will have to install quite a few more of them than seems to be on their minds right now...or attract DC Fast providers to install close to their sites.
For workplaces, given that most commutes wouldn't need 8 hours of level 2 charging, they should expand level 2 charging stations to have multiple connections per charge station, then have a smart scheduling system that charges vehicles based on need (with some max limit for fairness). The same could be done at hotels with fast chargers - multiple connections per station, with a smart scheduling system. The system has to allow people to plug in and forget about it.
 

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Here's a copy of a piece that I wrote earlier this week on the subject:

It's a mistake to try to box in drivers' potential needs. In a public charging situation it's impossible to know what any particular driver needs when they pull in.

The way to pull this off cost effectively is to install a mix of chargers at these locations with different power delivery and cost options. There are three different power levels that can be delivered with virtually the same electrical inputs: L2, medium speed DCFC, and battery backed high speed DCFC.

Each of these take inputs in the 24-40 kW range. This is important because these types of circuits have minimal or no demand charges.

Each have different delivery and power options. L2 can be up to 11 kW (19.2 kW max per specification) for some vehicles. Medium speed DCFC converts the AC input to DC and delivers the maximum power of the input circuit. So, if it's a 30 kW input, then 30 kW can be delivered to the vehicle. Battery backed DCFC charges the included battery pack (Freewire has 160 kWh pack), then the battery and the input can be combined to deliver charging at rates up to 120 kW.

If all locations have a mix of these types of chargers, then the needs of anyone who pulls up can be served.

ga2500ev
 

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I could even make the argument that it's appropriate for local places where people only spend an hour or so. Remember, most people only drive ~30 miles per day, so that's just a little over an hour of level 2 charging. Even level 2 charging at a restaurant or grocery store might work as a loyalty perk. After all, people will shop at a grocery store just to save a few cents on gas.
Here is a snippet of another piece that I posted earlier this week in rebuttal to this idea.

L2 doesn't really work in shared opportunity charging situations. Generally folks using the current public L2 infrastructure are in one of two or three places. The first is that it's a convenient opportunity, but completely unnecessary. I have access to a Volta at the grocery store between home and work. It fits in this category. If I happen to stop in to that store, I'll plug in. But since it's 6 miles from both home and work, only 1 time out of 100 do I really need it.

The second is coming in with a plan to charge for several hours and finding something else to do in the meantime. [There are folks who have] told several stories of doing this activity, trading time for free charging.

The third is the most problematic: Someone really needs a decent charge and simply doesn't have time to wait. No matter how many sockets are available, or how little it costs to charge, it simply isn't helpful.

We have to supplement all L2 infrastructure with faster charging options in virtually all shared charging situations. It doesn't have to be every spot prevalent. But it does need to be on every site that offer charging. It doesn't have to be 150 kW mega speed stations. A combination of medium speed stations up to 50 kW and battery boosted stations would help. It wouldn't need to be free. In fact, it shouldn't be free as the cost of electricity, maintenance, and cost recovery needs to be factored in. They can grow more slowly to take on the upcoming load because they can charge more cars per day than a 240V outlet.

We really have to stop thinking that we can just take what works for us as an individual at home and translate it to hundreds, thousands, or millions of public charging spaces. 240V/L2 doesn't scale well. We need other options out in public.

ga2500ev
 

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I've been wondering about the U.S. Transportation Bill (hasn't passed but likely) and how they plan to increase the number of EV stations. What will actually get built? Hopefully they'll build stations with Fast Chargers, because that would be truly useful for people on long trips and EV owners who don't/can't have a charger at home (for example, tenants in apartment building).
I too believe they need to be DC fast chargers. However, DCFC power can range from barely above L2 power ranges all the way up to 500 kW and beyond. I think many EV people are so conditioned to think of DC as always in the maximum power range, they miss the point that lowered powered DCFC also can serve useful purposes.

The primary point I push is the fact that DCFC, regardless of power level, can offer every car up to the maximum power available. Many have offered the idea of using max power L2: 19.2 kW [email protected] as a public charging option. However, there are only about 3 models that can actually take advantage of such power levels. Converting that same power to DC creates a situation where any car with a DC interface can take advantage of that maximum power level which is nearly 3 times as fast as most current EVs can charge at via L2.

So, echoing my other posts above, the wide scale deployment of charging stations should be a mix. It's fine to have some L2. But higher powered DCFC stations at virtually any higher power level should be part of the mix too.

Ultra high speed DCFC should be reserved for road trip travel corridors. Their basic problem is that the cost of infrastructure, operation, and maintenance is so high that from a cost standpoint they can only effectively be used for long distance travel situations. Electrical demand costs for such stations are a killer cost unless they are very heavily used. And with so many other options for charging in non road trip situations, likely deployments outside of travel corridors will not be cost efffctive.

It's unclear if battery backed DCFC, such as the current FreeWire offerings, will prove to function from a cost standpoint in more lightly used corridors. On the one hand they can eliminate thousands of dollars of electrical demand fees on a monthly basis. On the other, with prices approaching $200k, it may be too costly to pay off the capital investment required to install them. My hope is that part of the infrastructure bill can offset some of the costs such that willing retail and MUD owners may consider installing them as part of mix of chargers.

ga2500ev
 

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Discussion Starter · #12 ·
Here is a snippet of another piece that I posted earlier this week in rebuttal to this idea.

L2 doesn't really work in shared opportunity charging situations. Generally folks using the current public L2 infrastructure are in one of two or three places. The first is that it's a convenient opportunity, but completely unnecessary. I have access to a Volta at the grocery store between home and work. It fits in this category. If I happen to stop in to that store, I'll plug in. But since it's 6 miles from both home and work, only 1 time out of 100 do I really need it.

The second is . . .
Well thought out + well said.
 

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Currently the number of Level 2 stations outnumber Fast Charging stations. Just thinking out loud here, how useful are L2 stations set up a retail centers? If you plug in at a grocery store and stay for an hour, even two, your car has gained some range--but not very much.
They can be very useful, especially as they become common enough that they are nearly everywhere we park for errands. I haven't been to the mall in a year but prior to that I could plug in for free and while inside gain more miles than my round trip there. Same with a run for groceries, the 40 minutes inside nets me almost exactly my round trip range. Things like that could make an EV viable for someone that can't charge at home but doesn't drive many miles which is a lot more people now. While I can charge at home pretty cheap at about 6.5 cents I also now park/shop where I can charge for free which benefits me and the stores. It's only going to be more and more common and we should see an explosion of L2 over the next few years. Because of the coming commercial real estate crash with all the new work from home situations, some of the smarter building management companies will install some L2 which their tenants and potential tenants can use as a perk to retain employees.

Fast chargers are just for trips, so travel corridors and that's about it. For their high cost ($35K+) the ROI isn't there for other uses. A local store, or more likely the strip mall owner, can justify putting in some L2 to entice more shoppers in and for longer stays. Or the town's public parking garage if they put in 30 of them. No need for CCS since I may not be parked long enough that it's a benefit, or I'm away to long and my car is taking up a space when it's been sitting full for two hours. Some places may never have a charge spot, like the post office where no customer is there longer than 10 minutes.
 

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How about installing Level 2 plug outlets? You use your charge cord and add a few miles. Much lower equipment costs and a shopping center/mall could install a bunch of outlets without dedicating a lot of spaces as EV only.
 

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Well they are a lot more useful than level 1.
 

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Well they are a lot more useful than level 1.
One could argue L1 is ideal for long term airport parking, cheap for installation and plenty of time to top off the HV battery. Probably better than L2 because they can install far more 5-15 outlets for the money than L2 units.

As stated above, there is a time and place for all types of charging options. In general though, I agree with your statement for most use cases.
 

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How about installing Level 2 plug outlets? You use your charge cord and add a few miles. Much lower equipment costs and a shopping center/mall could install a bunch of outlets without dedicating a lot of spaces as EV only.
Take a read of my post #10 above as to why this isn't going to work.

ga2500ev
 

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Probably better than L2 because they can install far more 5-15 outlets for the money than L2 units.
120V and 240V outlets/circuitry are essentially identical. It makes little sense to install a 5-15 when a 6-20 or 6-30 can be installed in exactly the same spot offering much more available power. And if every spot is electrified, it doesn't really matter if charging finishes faster.

ga2500ev
 

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120V and 240V outlets/circuitry are essentially identical. It makes little sense to install a 5-15 when a 6-20 or 6-30 can be installed in exactly the same spot offering much more available power. And if every spot is electrified, it doesn't really matter if charging finishes faster.

ga2500ev
It is the same cost at the 'last mile' but make a difference upstream. Transformers may have to be upgraded.

As much as some dislike shared circuits, parking lots may have the best use case. For the airport LT parking, let's say 100A is shared by the whole row with 20 spaces. If every spot is charging, they get 5A, if 3 cars are charging, they get the full 32A. For work place charging, maybe we share a 100A circuit between 10 parking spots... when only 3, each gets 7.68KW and when all 10 spots are EVs, that's 2.4KW each,
 

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To implement that approach, you would need EVSE equipment that can communicate with one another to limit the charging current to each port. Kind of kills the supposed cheapness of the solution.

If one is going to go that route, seems to me it would be better to go ahead and create a set of DCFC dispensers that share a common power source. Why limit the input to a single car to the max on its onboard charger? Instead of charging many cars slowly in parallel, charger cars serially quickly. That way when there are cars that have limited time frames (not really in a long term airport parking lot situation though), one can schedule how long the car will be there, and deliver the needed power to charge the vehicle in the timeframe available.

Or just keep it simply and dedicate a circuit to each parking spot.

ga2500ev
 
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