Multi-family Level 1 or Level 2 infrastructure?

[wwarren]

I'm a Tesla owner, and engineer with a real estate development company. We have an affordable housing development coming up in Atlanta across the street from a public park, where the city requires 20% of parking spaces must be built with infrastructure for EV charging, which in the case of this project will be 40 charge spots. There doesn't seem to be a mandate for what level of charging is required however. We are debating which to install. Level 1 would be less expensive to build than Level 2, but charges take longer. My thinking is that Level 1 charge times are OK for a parking lot meant for residential tenants. Level 2 chargers may cause problems by drawing non-tenants who want a bit of charge while visiting the adjacent park.

Thoughts?

 

[doghousePVD]

Level 1 really is not satisfactory. An overnight charge does not fill a battery. For example, a 80% discharged X or P 100 would take at 3 days and nights to recharge.

Yes, some people can recharge at level 1 for minimal driving. Sort of like have a roof that only leaks when it is raining hard.

 

[wwarren]

Level 1 really is not satisfactory. An overnight charge does not fill a battery. For example, a 80% discharged X or P 100 would take at 3 days and nights to recharge.

Yes, some people can recharge at level 1 for minimal driving. Sort of like have a roof that only leaks when it is raining hard.

Keep in mind, it's affordable housing. Plug-in hybrid would be the most I'd expect anyone to possibly have there for a few years until used electrics fall more in price.

 

[scubastevo80]

Level 1 really is not satisfactory. An overnight charge does not fill a battery. For example, a 80% discharged X or P 100 would take at 3 days and nights to recharge.

Yes, some people can recharge at level 1 for minimal driving. Sort of like have a roof that only leaks when it is raining hard.

Agreed - while level 1 may work for current levels of EV adoption, it won't be sufficient in 5-10 years where most cars have over 300 miles of range and need faster charging speeds. What is the delta on the cost for level 2 vs level 1? Are you looking at the cost of a standard 5-15 outlet vs an actual charging station?

 

[doghousePVD]

Keep in mind, it's affordable housing. Plug-in hybrid would be the most I'd expect anyone to possibly have there for a few years until used electrics fall more in price.

I suspect plug-in hybrid will be an extinct option quite shortly (< 5 years). A lot of added complexity for little real world improvement. There will still be need for some ICE long term, but I think we will see mass adoption of EV well within the lifespan of your apartment building (20 years? 40 years? More?), especially in "affordable housing". Get the buried wiring in place while it is cheap during construction. What kind of metering is still evolving, but basic 240 volt wiring will be essential regardless.

 

[cpa]

Get the buried wiring in place while it is cheap during construction. What kind of metering is still evolving, but basic 240 volt wiring will be essential regardless.

I think that this is a good start. You might wish to have a handful of L2 stalls available at the outset for tenants who might need L2. Maybe 30 L1 with 10 L2 with the understanding that you will transition the L1 to L2 over a certain timeframe.

I am sure that there can be arrangements made with ChargePoint or other parties to have the equipment dedicated to tenants so that they can pay for the electricity that they use while excluding freeloaders who happen to spend some time across the street at the public park. Or you could have the charging stations and their apartment keys somehow connected. There has to be a way in 2019 to be able to match up EV charging with resident credentials.

 

[RTPEV]

I don't agree with those saying level 1 is not sufficient. True, it won't recharge 80% of a battery overnight. But it doesn't need to. You only need to replenish what you used during the day. And for the average person, that is 40 miles. At L1 (4 miles/hour recharge rate), 10 hours is going to replenish that amount. If the resident takes a trip, or has the occasional need for faster charging, then there are public chargers that should be available off-site. But for residential charging, L1 would seem to be adequate, and if it's a case of being able to install 2X the amount of charging capacity, it's probably preferable.

Having said that, there are other options as well that may be better than L1 charging that address the concerns with outsiders using the charging stations. You should probably utilize Chargepoint (or similar) systems that would allow you to restrict access to specific users (i.e. residents that have been provided access or a complex charging card) and/or charge a fee for charging to help cover costs. By charging a fee, you will likely provide a disincentive for people coming from the park.

 

[ai4px]

Off hand, I'd say L1 will fill the needs of most city dwellers. If you travel a lot of miles one day and don't get full the first night, there's always tomorrrow. HOWEVER... my concern is about the longevity of the 120v plug. At least use hospital grade plugs or provide a method for me to lock my portable EVSE to the post. Even an eye (ie a flat plate tab with a hole in it) welded onto the post for a pad lock would allow me to pad lock my J1772 cable to the post and leave the EVSE plugged in, saving wear and tear. Not sure how expensive L1 charging "boxes" would be to buy relative to just going ahead and buying a clipper creek L2 EVSE on a post. Behind my office in Duluth GA, there's a handful of L1 outlet pedestals..... Here's a link to a pic I took on plugshare. These boxes provide a little pocket to set the EVSE inside out of the weather a bit.

PlugShare - Find Electric Vehicle Charging Locations Near You

 

[ai4px]

Also, if you are worried about others using the EVSEs, I've got an idea for you using RFID cards to limit access. PM me if interested.

 

[ralph142]

This is on street parking ? not associated with a specific building or apt ? I would think you'd want to go with a set up that allowed for residents only etc. Like a chargepoint station, but level one seems likely to be adequate for the projected use.

 

[doghousePVD]

I strongly disagree with the build-it-cheap&build-it-wrong myopic approach that the average person drives 40 miles. Nobody on the planet drives exactly 40 miles per day 365 days in a row for 20 years. And lots of people don't go home right after work, they go out to visit parents or see movies, and have to leave at 6 in the morning. Heaven forbid there is a traffic jam or holiday shopping or an emergency at a hospital 100 miles away or picking up a friend with a stuck car or an unexpected trip to the airport or lending the car to a spouse or ....

Averages in this case are worse than useless - they are dangerous and stupid. On average, only one person dies in a car crash, so let's put in only one seat belt. On average, you use only a few lights at a time, so let the house burn down if all the lights are turned on. Etc.

The OP was writing about a multi-decade wiring question, not whether one irrelevant anecdote about the non-existent average driver is doing this week.

The major advantage of distributed electric charging is that the wasted space of gas stations and wasted time going to them is eliminated. Why would anyone be encouraging people to use scarce public chargers?

 

[ralph142]

Whats the lowest cost type of ev kicking around, and how would it fair? used leafs perhaps? 50-90 mile range. I don't know how long they would take to fully charge on 120v. My normal use is certainly dealt with overnight or less at 120v 12 amps.

 

[RTPEV]

HOWEVER... my concern is about the longevity of the 120v plug.

L1 does not imply 120V outlet. It only implies 120V charging. J1772 L1 EVSEs do exist, although I must say that from a sturdiness point of view, I would expect a 120V outlet to do far better than a J1772 L1 station, and in the event of damage or just general wear and tear, it would be easier and cheaper to replace.

However, the Atlanta ordinance mentioned by the OP seems to only require "EV ready", not actual EVSE's or outlets, although it does require conduit, wiring and electrical capacity, the latter of which is probably what the OP is specifically concerned with: for the 40 spots, how much electrical capacity to install?

 

[RTPEV]

I strongly disagree with the build-it-cheap&build-it-wrong myopic approach that the average person drives 40 miles. Nobody on the planet drives exactly 40 miles per day 365 days in a row for 20 years. And lots of people don't go home right after work, they go out to visit parents or see movies, and have to leave at 6 in the morning. Heaven forbid there is a traffic jam or holiday shopping or an emergency at a hospital 100 miles away or picking up a friend with a stuck car or an unexpected trip to the airport or lending the car to a spouse or ....

Averages in this case are worse than useless - they are dangerous and stupid. On average, only one person dies in a car crash, so let's put in only one seat belt. On average, you use only a few lights at a time, so let the house burn down if all the lights are turned on. Etc.

The OP was writing about a multi-decade wiring question, not whether one irrelevant anecdote about the non-existent average driver is doing this week.

So where do you draw the line? You could use the same argument to basically PROVE that all EVs are pointless because at a moment's notice someone MIGHT invite you to dinner on a whim 150 miles away and you might not have the range to make if you have less than 100 miles of range. (I literally had someone contrive this example as a reason why an EV would never work for them).

The major advantage of distributed electric charging is that the wasted space of gas stations and wasted time going to them is eliminated. Why would anyone be encouraging people to use scarce public chargers?

I think this is the crux of why it is important to carefully consider the appropriateness of what level charging to provide. If it came down to a case of installing 40 L2 stations or 120 L1 stations, which would you take? (I used a ratio of 3:1 considering an electrical capacity ratio of 4:1, but also acknowledging an EVSE cost ratio of closer to 2:1) Are there alternative charging solutions (fast charging or L2 charging at shopping centers, hospitals, movie theaters). Sure, I would love to see L2 chargers everywhere, but budgets are usually limited.

And believe me, I've seen a lot of really STUPID installations of charging stations that make no sense whatsoever: a fire station that was just built down the street from me put in an L2 charging station...do we really think that a fire station is a destination that people are going to be spending hours at? I do applaud their efforts (they also covered their roof in solar panels), but that L2 station would have been SO much better in a parking deck downtown. And an L2 station in a prime spot at McDonalds seems to make no sense either.

And is 40 miles/day in an urban environment even an accurate measure? (I honestly don't know--it may be lower, it may be higher)

Even though it's just a single, specific case, my wife and I successfully charged TWO EV's from a single 120V outlet for a period of about 5 months.

 

[Darmie]

I’m surprised this AHD project offers options. Most funded endeavors carry out just what the letter of the law states to keep over runs low.
If an L2 options can be offered, I would say do it for the new Tenants. It’s interesting this type of infrastructure is now a requirement. If the city is requiring EV charging, make it the best it can be for all to benefit. I wouldn’t think a park user would stay longer than an hour or two. Besides, proper signage would keep the right actors in play anyway.

 

[wwarren]

Agreed - while level 1 may work for current levels of EV adoption, it won't be sufficient in 5-10 years where most cars have over 300 miles of range and need faster charging speeds. What is the delta on the cost for level 2 vs level 1? Are you looking at the cost of a standard 5-15 outlet vs an actual charging station?

It's a significant difference. With 200 parking required, we need 40 charging stations. 40 120V/15A vs 40 208V/40A is a big difference. Service size, conduit size, conductor size, even space within the equipment room.

 

[wwarren]

Thanks for the opinions. Given the way affordable housing development is financed, I'm told by our developers that there's basically no going back and upgrading something like this later. We make our money up front, and then have to operate the building for 20-30 years. Rents are designed to pay for operation, not profit. Nor are we able to charge tenants extra fees for anything like this. A fee to Chargepoint or other network is permissible though.

 

[wwarren]

I’m surprised this AHD project offers options. Most funded endeavors carry out just what the letter of the law states to keep over runs low.
If an L2 options can be offered, I would say do it for the new Tenants. It’s interesting this type of infrastructure is now a requirement. If the city is requiring EV charging, make it the best it can be for all to benefit. I wouldn’t think a park user would stay longer than an hour or two. Besides, proper signage would keep the right actors in play anyway.

Atlanta doesn't say whether we have to use Level 1 or Level 2, but just gets into charger and infrastructure requirements. It's our decision as the developer to decide what we can afford to put in. However, our mission statement is also to do right by our tenants and the community, so Level 2 isn't out of the question if it fits into the budget. We just want to spend the budget in a fashion that will be most beneficial. Level 2 chargers or Level 1 chargers plus better playground equipment and a bike share program for example.

 

[Big Earl]

L1 does not imply 120V outlet. It only implies 120V charging. J1772 L1 EVSEs do exist, although I must say that from a sturdiness point of view, I would expect a 120V outlet to do far better than a J1772 L1 station, and in the event of damage or just general wear and tear, it would be easier and cheaper to replace.

However, the Atlanta ordinance mentioned by the OP seems to only require "EV ready", not actual EVSE's or outlets, although it does require conduit, wiring and electrical capacity, the latter of which is probably what the OP is specifically concerned with: for the 40 spots, how much electrical capacity to install?

My approach would be to install a mix of shared Tesla wall connectors and shared J1772 stations.

The wall connectors would be hooked up in groups of four sharing a 100 amp circuit. At full capacity, that is 20 amps per vehicle, or a charging speed of 16 miles per hour on a Model 3.

The J1772 stations would be dual cord Clipper Creek (or similar) that share a 40 amp circuit. With two cars charging, each would get 16 amps, or about 13 miles per hour on your average EV.

These shared arrangements minimize wiring and number of circuits, while allowing faster charging during times when the stations aren’t in high demand. It also spreads the peak load out over time, minimizing utility demand charges.

Charging stations could be installed in phases as the EV population grows, as long as the wiring is installed during construction.

 

[RTPEV]

My approach would be to install a mix of shared Tesla wall connectors and shared J1772 stations.

Why bother with the Tesla wall connectors at all? A Tesla will charge just fine from a J1772. The reverse is not true. You could run into a situation where you have vacant Tesla stations because nobody owns a Tesla, and you've taken away the opportunity for those that may have a used LEAF or Volt to be able to charge.

 

[wwarren]

This is on street parking ? not associated with a specific building or apt ? I would think you'd want to go with a set up that allowed for residents only etc. Like a chargepoint station, but level one seems likely to be adequate for the projected use.

No, it's off street for a specific building. No gated access though, so anyone could drive into the lot.