How much should the HOA charge? (I'm the HOA president)

[gt2690b]

Many condo complexes have underground parking, with stable year round temperatures. I think most forum members are dramatically underestimating the cost for installing complete L2 charging systems rather vs the cost of a simple 110v outlet.

a NEMA 6-20 can use the same gauge and # of wires as a NEMA 5-15 or 5-20 i dont understand why it would cost vastly more? complete level 2 charging at 8~10KW sure that could require major infrastructure changes

 

[MP3Mike]

Many condo complexes have underground parking, with stable year round temperatures. I think most forum members are dramatically underestimating the cost for installing complete L2 charging systems rather vs the cost of a simple 110v outlet.

Sure, a simple 120v outlet install would be cheaper, but then the condo is on the hook to pay for electricity, you have to buy/implement some kind of billing system, or rely on the honesty of the people using it to properly log, report, and pay for the charging they use.

But really L2 charging doesn't need to cost much, if any more. Maybe a 240v breaker costs more than a 120v breaker, and you would need a larger distribution panel to install the same number of charging spots. But besides that the only difference in cost is if you install a receptacle or EVSE. (And if you want billing to make sure that Internet connectivity is available.) And if you go with just receptacles, then that means the people charging have to buy their own EVSE. (Which is about half the cost of the Tesla Wall Connectors.)

 

[Rocky_H]

I think most forum members are dramatically underestimating the cost for installing complete L2 charging systems rather vs the cost of a simple 110v outlet.

You're mashing together two totally separate topics and therefore oversimplifying.
I already covered one of these, that the cost difference between level 1 and level 2 power levels on outlets is literally $0, so that's not "dramatically underestimating" anything. So your premise is false to think that "a simple 110v outlet" is cheaper because it is a lower voltage.

Now doing the full service system, with monitoring and billing has service fees and a lot of other things, which @MP3Mike covers.

 

[MP3Mike]

I already covered one of these, that the cost difference between level 1 and level 2 power levels on outlets is literally $0, so that's not "dramatically underestimating" anything.

Well, it isn't literally a $0 difference. A quick look at Home Depot:

• 120v 20A total: $12.36
  • 5-20 outlet $4.56
  • Single-pole 20A breaker $7.80
• 240v 20A total: $26.89
  • 6-20 outlet $6.65
  • "Quadplex" double-pole 20A breaker $20.24 ($40.48 for the breaker, but it serves two separate circuits/outlets.)

So, it costs about $15 more, which really isn't significant. (Using the "Quadplex" breaker means you don't need a larger distribution panel, unless you were already using half-sized breakers.) The cost difference is probably less for a contractor buying in bulk, but a 240v breaker is always going to cost more than a 120v one.

There is one advantage to going with 120v outlets: people could use them for convivence things like vacuuming their vehicle.

 

[MP3Mike]

While a 240v outlet costs $15 more for the install, it makes a world of difference in the end-user experience. But by spending that initial $15 extra they would save ~$16/month on wasted electricity from the inefficiency of 120v charging, not to mention the reduced wear and tear on the vehicle from running the pumps, etc. in the car for half as long while charging.

 

[Eric33432]

It is the same amount of power, and therefore the same impact to the overall grid, if you charge for 10 hours at 120 volts and 12 amps (1.44 kWh), or for 2-1/2 hours at 240 volts and 24 amps, letting the Tesla Wall Connectors (or similar devices) figure out the load management, with three benefits, 1) the 240 volt charging is marginally more efficient, 2) the user experience will be much better for anyone who needs more than the minimal miles that 120 volt charging can add to their battery and 3) billing capability of the TWC.

 

[Eric33432]

This is worth a read regarding Tesla commercial and multi-unit charging.

https://digitalassets.tesla.com/tesla-contents/image/upload/Tesla_Wall_Connector_ApplicationNote.pdf

Note: while you can install more units on a 225 amp panel, Tesla recommends the above for the best user experience depending on application (apartment vs condo).

Since the Tesla specification is for 208 or 240 volts, it looks to me like they are considering a single phase 225 amp panel. A 3 phase panel, which in almost all cases would be 208 volts, allows for 1.73 times more power than a single phase panel, and should support 30 Wall Connectors.

Edit: The Tesla specification is DEFINITELY for a 225 amp single phase panel. Their one line drawing shows the panel fed with a two pole breaker. A three phase panel would have a three pole breaker.

Well, it isn't literally a $0 difference. A quick look at Home Depot:

• 120v 20A total: $12.36
  • 5-20 outlet $4.56
  • Single-pole 20A breaker $7.80
• 240v 20A total: $26.89
  • 6-20 outlet $6.65
  • "Quadplex" double-pole 20A breaker $20.24 ($40.48 for the breaker, but it serves two separate circuits/outlets.)

So, it costs about $15 more, which really isn't significant. (Using the "Quadplex" breaker means you don't need a larger distribution panel, unless you were already using half-sized breakers.) The cost difference is probably less for a contractor buying in bulk, but a 240v breaker is always going to cost more than a 120v one.

There is one advantage to going with 120v outlets: people could use them for convivence things like vacuuming their vehicle.

Wouldn't you need GFCI breakers for outlets?

 

[MP3Mike]

It is the same amount of power, and therefore the same impact to the overall grid, if you charge for 10 hours at 120 volts and 12 amps (1.44 kWh), or for 2 hours at 240 volts and 24 amps, letting the Tesla Wall Connectors (or similar devices) figure out the load management, with two benefits, 1) the 240 volt charging is marginally more efficient, and 2) the user experience will be much better for anyone who needs more than the minimal miles that 120 volt charging can add to their battery.

No, it isn't the same impact to the grid, and not just marginally more efficient. 120v charging takes about 16% more energy to complete the charge. (In your example wasting over 2 kWh.)

 

[DuncanM]

It is the same amount of power, and therefore the same impact to the overall grid, if you charge for 10 hours at 120 volts and 12 amps (1.44 kWh), or for 2-1/2 hours at 240 volts and 24 amps, letting the Tesla Wall Connectors (or similar devices) figure out the load management, with three benefits, 1) the 240 volt charging is marginally more efficient, 2) the user experience will be much better for anyone who needs more than the minimal miles that 120 volt charging can add to their battery and 3) billing capability of the TWC.

The grid has be sized to handle peak loads.

 

[Eric33432]

I wish they would suggest spending more to locate charging spots further from building to avoid ICEing. I personally know of several cases where ignoring this results in failure.

Easy to do by upsizing the wire for voltage loss for longer runs, of course that will cost more.

The grid has be sized to handle peak loads.

The Tesla Wall Connectors will spread the load out over longer time frames, and since the cars will charge faster, they may be able to be charged at times when the grid is less highly loaded. Charging at 120 volts and 12 amps means the chargers are pretty much always in use as long as the vehicles are plugged in.

 

[ai4px]

120 5-20 outlets at airport parking is certainly not a bad idea but for basically the same installation costs you could do something like 240V nema 6-20s or maybe even both with a neutral just because you are wasting so much power charging at 120V

Alternatively you could spend the up front capital for real chargers and charge per kw to make up for your costs (and some) and you'd likely not even need as much capacity as dedicated 120v outlets because the chargers would manage the load and you wouldn't be wasting 40% on inefficiencys

All very true. I was trying to make it sound more attainable and less expensiveable (lol) to the airport. Columbia is a lot closer to me than Charlotte. I did mention to CAE that CLT had business valet parking that I used all the time and that could be a revenue generator for them if they'd top off cars while valet parked. Sorry, I'm done hijacking this thread... carry on!!!

 

[Eric33432]

No, it isn't the same impact to the grid, and not just marginally more efficient. 120v charging takes about 16% more energy to complete the charge. (In your example wasting over 2 kWh.)

Did you not read all my posts? 120 volt charging is not my example, I am a proponent of 240 volt charging.

 

[MP3Mike]

Wouldn't you need GFCI breakers for outlets?

Yeah, I guess you would to meet current code in most locations. Which really ends up pushing you to installing something like the Tesla Wall Connector where you wouldn't need the more expensive GFCI breakers. (Since it would add ~$60 to the 120v or ~$120 to a 240v outlet install.)

That means a Tesla Wall Connector install only costs about $250 more than a 20A 120v outlet setup. (Since you would have to spend ~$270 on a mobile EVSE and adapter with the 120v install.)

 

[Big Earl]

Since the Tesla specification is for 208 or 240 volts, it looks to me like they are considering a single phase 225 amp panel. A 3 phase panel, which in almost all cases would be 208 volts, allows for 1.73 times more power than a single phase panel, and should support 30 Wall Connectors.

Edit: The Tesla specification is DEFINITELY for a 225 amp single phase panel. Their one line drawing shows the panel fed with a two pole breaker. A three phase panel would have a three pole breaker.

Wouldn't you need GFCI breakers for outlets?

Very few panels can accommodate 60 circuit breaker handles, which is what would be required for 30 wall connectors. Most are 42.

Regardless of 208 or 240, you can put as many as will fit in the panel, then configure the system based on the panel or transformer’s maximum available power.

Tesla’s single line diagram is a simplified example. Your installation may vary.

 

[dakhlkt22]

Well, it isn't literally a $0 difference. A quick look at Home Depot:

• 120v 20A total: $12.36
  • 5-20 outlet $4.56
  • Single-pole 20A breaker $7.80
• 240v 20A total: $26.89
  • 6-20 outlet $6.65
  • "Quadplex" double-pole 20A breaker $20.24 ($40.48 for the breaker, but it serves two separate circuits/outlets.)

So, it costs about $15 more, which really isn't significant. (Using the "Quadplex" breaker means you don't need a larger distribution panel, unless you were already using half-sized breakers.) The cost difference is probably less for a contractor buying in bulk, but a 240v breaker is always going to cost more than a 120v one.

There is one advantage to going with 120v outlets: people could use them for convivence things like vacuuming their vehicle.

A condo building shouldn't be asking Uncle Jimmy to see what he can do to wire things up after he goes to Home Depot to buy an outlet. The condo, if they have a reasonably professional property manager, should hire a licensed company. In my limited experience as a homeowner, a licensed electrician will charge based on the value they are delivering to the client. The electrician's charge for a 110V outlet is vastly different than a 240V circuit with a large circuit breaker, and that charge has nothing to do with how much it costs to buy the parts at Home Depot, and the time/labor is roughly similar for any particular single circuit.

 

[MP3Mike]

In my limited experience as a homeowner, a licensed electrician will charge based on the value they are delivering to the client. The electrician's charge for a 110V outlet is vastly different than a 240V circuit with a large circuit breaker, and that charge has nothing to do with how much it costs to buy the parts at Home Depot, and the time/labor is roughly similar for any particular single circuit.

Then the electrician's you have dealt with are ripping you off. All of the ones I have used charged for materials, including their markup, and labor. Nobody said anything about a "large circuit breaker", I was comparing 20A to 20A so that wire costs remained identical. (Some even let you provide your own materials and then they only charge for labor, but then they won't provide a warranty for defective materials. i.e. if a circuit breaker fails you are on your own, or have to pay for them to replace it.)

Very few panels can accommodate 60 circuit breaker handles, which is what would be required for 30 wall connectors. Most are 42.

That is what the "Quadplex" breakers are for. They take two slots in the panel and provide two independent 240v circuits. So, you put 15 of those breakers in a panel capable of handling 30 breakers and you have support for 30 Wall Connectors. You say most panels handle 42, that means you could put 21 "Quadplex" breakers in to support 42 Wall Connectors. (Or you could put fewer and have room for some 120v convenience outlets.)

 

[dakhlkt22]

Then the electrician's you have dealt with are ripping you off. All of the ones I have used charged for materials, including their markup, and labor. Nobody said anything about a "large circuit breaker", I was comparing 20A to 20A so that wire costs remained identical. (Some even let you provide your own materials and then they only charge for labor, but then they won't provide a warranty for defective materials. i.e. if a circuit breaker fails you are on your own, or have to pay for them to replace it.)

Have to be licensed (after training, exam, and years of experience) and insured here to pull an electrical permit, so maybe our market is different than other markets. I get the impression in other parts of the country, even a homeowner can do electrical work and get it approved. In an area that regulates electrical more loosely, the costs may be very different.

 

[gt2690b]

Have to be licensed (after training, exam, and years of experience) and insured here to pull an electrical permit, so maybe our market is different than other markets. I get the impression in other parts of the country, even a homeowner can do electrical work and get it approved. In an area that regulates electrical more loosely, the costs may be very different.

ironic given that New York was the first state to deregulate electricity

 

[dakhlkt22]

ironic given that New York was the first state to deregulate electricity

NYC is the densest city in the US. When something goes bad, it could affect all the buildings on a block. Many buildings are attached to each other. So a certain amount of enhanced caution is warranted here.

 

[gt2690b]

NYC is the densest city in the US. When something goes bad, it could affect all the buildings on a block. Many buildings are attached to each other. So a certain amount of enhanced caution is warranted here.

hence why it is strange they'd want to deregulate there so fast