Load Management for EV Charging

[Green1]

Is anybody aware of other level 2 chargers that provide 60A or 80A with built in load management? Has anybody used the Emporia with load management? Are there other options I should be considering?

I use an OpenEVSE tied into my Home Assistant automation system. it varies the output based on available solar generation after subtracting use by all the other loads in my house. Right now we only have 1 EV, but when my wife next replaces her vehicle I plan to get a second OpenEVSE and modify the Home Assistant automations to split that solar power between the 2 vehicles.

OpenEVSE can be built in different configurations, I have mine set with a limit of 32A, but you can easily do up to 80A.

Sponsored

 

[Jperrigo]

Thank you all for your input. I’ll get a proper load calculation done. I did talk to an engineer at the power company today and he said the transformer that feeds our house and 4 other houses is only 25kW, and the FCSP pulls 19.2kW continuous at 80A. The transformer can handle 175% of it’s rated load, but that is still pretty small. They are going to need to upgrade the transformer no matter what charger I use.

As far as the the 80A I don’t think I’d use it very often and would probably typically run it at 48A. It would be nice to have the option when in a hurry but I don’t think it is worth the extra cost in install, so I’m leaning toward something like the emporia.

 

[Runaway Tractor]

Thank you all for your input. I’ll get a proper load calculation done. I did talk to an engineer at the power company today and he said the transformer that feeds our house and 4 other houses is only 25kW, and the FCSP pulls 19.2kW continuous at 80A. The transformer can handle 175% of it’s rated load, but that is still pretty small. They are going to need to upgrade the transformer no matter what charger I use.

As far as the the 80A I don’t think I’d use it very often and would probably typically run it at 48A. It would be nice to have the option when in a hurry but I don’t think it is worth the extra cost in install, so I’m leaning toward something like the emporia.

You are still overthinking this. You do not need a load study or to spend any money thinking about what to do. Install the charger wherever you want it, on a 100 amp breaker. The end. Set it for whatever max you want, whether it is a 80 or something else, and enjoy your charger. You're not going to max out your 200 amp service, and everything will work perfectly fine. Doing anything beyond that will be wasting your time and money.

If the power company wants to upgrade their transformer at some point, that will be up to them, at their expense, and not your problem.

 

[RickLightning]

Thank you all for your input. I’ll get a proper load calculation done. I did talk to an engineer at the power company today and he said the transformer that feeds our house and 4 other houses is only 25kW, and the FCSP pulls 19.2kW continuous at 80A. The transformer can handle 175% of it’s rated load, but that is still pretty small. They are going to need to upgrade the transformer no matter what charger I use.

As far as the the 80A I don’t think I’d use it very often and would probably typically run it at 48A. It would be nice to have the option when in a hurry but I don’t think it is worth the extra cost in install, so I’m leaning toward something like the emporia.

You are still overthinking this. You do not need a load study or to spend any money thinking about what to do. Install the charger wherever you want it, on a 100 amp breaker. The end. Set it for whatever max you want, whether it is a 80 or something else, and enjoy your charger. You're not going to max out your 200 amp service, and everything will work perfectly fine. Doing anything beyond that will be wasting your time and money.

If the power company wants to upgrade their transformer at some point, that will be up to them, at their expense, and not your problem.

It depends.

I have 200amp service, as does my neighbor. When I briefly considered the Ford Charge Station Pro for the future, I reached out to my utility company. They actually dispatched trucks to pull the cover off and examine the cable (really?). They said "If you upgrade to 400amps (which is really 320 load), before they do, it's free. Whoever is the 2nd to upgrade has to pay for a new transformer, and it will be a few hundred."

 

[Green1]

It depends.

I have 200amp service, as does my neighbor. When I briefly considered the Ford Charge Station Pro for the future, I reached out to my utility company. They actually dispatched trucks to pull the cover off and examine the cable (really?). They said "If you upgrade to 400amps (which is really 320 load), before they do, it's free. Whoever is the 2nd to upgrade has to pay for a new transformer, and it will be a few hundred."

You're still missing the point, there's no need for you to upgrade your service entrance, it's well above the size of the charger. If their transformer can't handle the power draw from your house, that's their problem, not yours. If the main breaker to your house is tripping, that's a you problem not them, but the odds of that happening are basically zero. For many years I had a 100 amp service entrance a car charging at 32 amps, and a hot tub with a max draw of 40 amps, plus all the other loads in the house including electric dryer and stove etc. I'm not going to say I recommend it, but I still never tripped the main breaker, and I certainly didn't do any balancing of what loads were on when, I just used them when they were convenient.
I did upgrade to a 200 amp service entrance, but that was more a function of the fact that I moved the service entrance as part of some other renovations rather than a standalone upgrade. When we had to move it anyway, it made sense to upgrade, because the price difference was minimal.
Despite the fact that my garage basically has a dedicated hundred amp service for two light bulbs and a truck, I still never charge above 32 amp.

 

[Runaway Tractor]

It depends.

I have 200amp service, as does my neighbor. When I briefly considered the Ford Charge Station Pro for the future, I reached out to my utility company. They actually dispatched trucks to pull the cover off and examine the cable (really?). They said "If you upgrade to 400amps (which is really 320 load), before they do, it's free. Whoever is the 2nd to upgrade has to pay for a new transformer, and it will be a few hundred."

When not associated with a customer requested service upgrade, the transformer is never going to be his cost. If the power company needs to right-size their transformer to match the currently installed customer service, that will be 100% the power company's problem to pay for. Probably going to be a common problem since most transformers were right-sized long before the heavy load of EV chargers existed. Nobody ever came close to using their 200 amp service capacity so they knew they could put in a smaller transformer for less money.

Of course if a customer wants a service upsize, and the existing transformer can't handle it, then yes I'd expect what you described. That can get very expensive very quickly.

Sponsored