Load Management for EV Charging

[Jperrigo]

My FCSP has arrived and I'm looking at options for install with limited power available. Our service is 200A and we are fully electric (heat pump, furnace, range, hot water, dryer, steam shower, etc...) so we don't have much overhead. I don't think we'd get signed off if we added an additional 100A breaker with the FCSP at 80A, and we'd probably occasionally trip our main. Where I want to put the charger is also right next to where the service comes in, but 25'+ from our main panel. If we came off the the main panel we'd be going through the crawl space and probably need about a 40' run. I had an electrician come out today and they suggested coming directly off of the disconnect next to the meter and using a load management relay so it would shut off the charger any time we started drawing too much. There is a 100A relay (PSP SAK-100MS-M) that should work, but it is over $1300 for the relay alone, not including install. Install including the relay was quoted at $3740.

So I figure I have a few options:

• Upgrade our main service to 400A (320A)
  • Pros: Plenty of overhead to run the full 80A with room for future upgrades
  • Cons: Expensive - Electrician estimated $8k for the service upgrade alone
• Use the 100A load management relay tied into the feed
  • Pros: Could use the FCSP at 80A
  • Cons: Still rather expensive, and may shut the charger off at times
• Run a 60A circuit from the main panel instead of 100A and run the FCSP de-rated
  • Pros: Probably wouldn't overload our panel/service and would be cheaper install than 100A
  • Cons: FCSP would be limited to 48A, could possibly still overload the panel, still need a long run from the panel to charger location
• Sell the FCSP and install an Emporia EV charger with load management
  • Pros: Wouldn't ever overload the panel/service due to the load management, Could sell the FCSP for about the cost of the Emporia
  • Cons: Emporia maxes out at 48A (load management might not even be necessary)
• Find another charger with load management that can provide 60A or 80A
  • Pros: Would solve most of my problems (fast charging with overload protection for reasonable cost)
  • Cons: I'm not aware of any 60A or 80A chargers with load management

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?

Thanks in advance!

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[Maquis]

The first thing your electrician should have done is an NEC load calculation. This would determine exactly how much capacity remains. Then you can make an informed decision. Right now, you’re just guessing.

 

[hturnerfamily]

I don't think you're anywhere near 'full capacity' or in any worry of regularly tripping your main breaker... 200amps of Main Power is at 240v... therefore it's akin to a comparison of 400amps at 120v, which is what most of your normal everyday usages are about.
240v appliances don't run constantly, and don't come on sometimes even on an everyday basis. Your oven may be used sparingly, and usually NOT at full output, even then. Your stove might be used every evening, but again, NOT at full output with ALL eyes on at the same time, etc. Your steam shower is likely not used at the same time other appliances are going full blast, etc.
I have a home with a typical 200amp Main EXTERIOR panel. My home's SUB PANEL, which is also 200amps, is inside the home.
The exterior panel is an excellent place to run no less than TWO NEMA 14-50 240v outlets for our EVSE needs. It also has several smaller 'exterior' light and irrigation panel circuits.
The interior panel has not only all of our ALL-ELECTRIC home appliances, including no less than THREE Air conditioning systems(30amp mini-split, and two 30amp 3-ton heat pumps), but the STOVE, OVEN, WATER HEATER, DRYER, and everything else any typical home requires. We have also TWO 240v 20amp EVSE outlets that make use of sharing a circuit with the mini-split, when not in use, and the outside irrigation well pump, when not in use, etc.

We come NO WHERE NEAR ever having any 'head room' issues with power, and we have TWO EVs that sometimes BOTH charge simultaneously, overnight.

 

[Grease Lightning]

So I figure I have a few options:

The first thing you should do is consider how much truck energy you will use daily, what is your needed recovery time to “full charge”, and what is your worst case scenario need.

A 48 amp EVSE can take an ER Lightning from 10% to 85% in around 9.5 hours. While there is use cases that need the full battery in the 7 hour range the FCSP can offer.

If your “overnight downtime” is usually 8 hours or more, I would suggest installing it on the 60 amp breaker as it would cover most use cases. You always have the option to DCFC in those rare time you need just that little more.

 

[RickLightning]

IMO, there are only 2 reasons to use 80amps vs. 48amps:

1) You have a need to quickly replace energy during a 12 hour period on a regular basis, for another trip. Regular basis, because once in a blue moon wouldn't justify the expense of the heavier wiring and breaker.

2) You plan on installing the V2H solution (roughly $10K by the time you're done).

Otherwise, there's zero reason TODAY to go over 48amps.

 

[bmwhitetx]

My FCSP has arrived and I'm looking at options for install with limited power available. Our service is 200A and we are fully electric (heat pump, furnace, range, hot water, dryer, steam shower, etc...) so we don't have much overhead. I don't think we'd get signed off if we added an additional 100A breaker with the FCSP at 80A, and we'd probably occasionally trip our main.

We have electric cooktop, double oven, dryer and 11 tons of A/C over three units. And our 200A service has never come close to maxing out (our utility has a portal where we can see max demand). So I agree with @Maquis and @hturnerfamily - you need to determine if you have an issue first.

But I lived with the FCSP for over a year with it bulky connector and general software failure before switching over to an Emporia. I can now easily change the charge rate on the fly while charging with their app and cable handling is much better.

 

[Henry Ford]

Install the 100 amp breaker. As others have said, it will likely never trip the main breaker but if it does, derate the FCSP to 64 amps or whatever works.

I have two FCSPs in different locations. One is set to 32 amps, the other is set to 64 amps.

 

[The Weatherman]

I loaded a 100A breaker in my 200A panel after doing the NEC load calculation and determine I had just enough room. However, I have since derated the FCSp to 60A. It still charges back to my 90% target in just a few hours (3-5). I’m sure I could drop to 48 without issue.

By the way I derated it after having an issue last summer with it derating its charge on its own due to overheating. I’ve not problem since.

Just my experience.

 

[pullinggs]

Sell the FCSP and install an Emporia EV charger with load management

• Pros: Wouldn't ever overload the panel/service due to the load management, Could sell the FCSP for about the cost of the Emporia
• Cons: Emporia maxes out at 48A (load management might not even be necessary)

As others have said, the use case for maximum-rate charging is atypical. If that's you, then you need "something more."

This would be my choice. I derate my Emporia EV to 24A (why push things?) and charge while I'm asleep. By the time I wake up, the truck is ready to go. YMMV.

 

[RocketGhost]

If you don't need faster charge speeds, just go the cheap route and put a 50 or 60 amp circuit for the charger. I have a 50a and charge at 40a. If whatever charging capacity you end up with causes problems, just derate the charger. Or you can schedule charging for when your other loads are light (e.g. at night).

I'm fortunate that my house has 320a service. It was far more than needed whenever it was put in, but we have since added a lot. Now there's 3 A/Cs, pool heat pump, hot tub, EV charger, electric oven, and dryer as the biggest loads. I have a 200a panel and a 120a panel.

 

[Formerly]

My FCSP has arrived and I'm looking at options for install with limited power available. Our service is 200A and we are fully electric (heat pump, furnace, range, hot water, dryer, steam shower, etc...) so we don't have much overhead. I don't think we'd get signed off if we added an additional 100A breaker with the FCSP at 80A, and we'd probably occasionally trip our main. Where I want to put the charger is also right next to where the service comes in, but 25'+ from our main panel. If we came off the the main panel we'd be going through the crawl space and probably need about a 40' run. I had an electrician come out today and they suggested coming directly off of the disconnect next to the meter and using a load management relay so it would shut off the charger any time we started drawing too much. There is a 100A relay (PSP SAK-100MS-M) that should work, but it is over $1300 for the relay alone, not including install. Install including the relay was quoted at $3740.

So I figure I have a few options:

• Upgrade our main service to 400A (320A)
  • Pros: Plenty of overhead to run the full 80A with room for future upgrades
  • Cons: Expensive - Electrician estimated $8k for the service upgrade alone
• Use the 100A load management relay tied into the feed
  • Pros: Could use the FCSP at 80A
  • Cons: Still rather expensive, and may shut the charger off at times
• Run a 60A circuit from the main panel instead of 100A and run the FCSP de-rated
  • Pros: Probably wouldn't overload our panel/service and would be cheaper install than 100A
  • Cons: FCSP would be limited to 48A, could possibly still overload the panel, still need a long run from the panel to charger location
• Sell the FCSP and install an Emporia EV charger with load management
  • Pros: Wouldn't ever overload the panel/service due to the load management, Could sell the FCSP for about the cost of the Emporia
  • Cons: Emporia maxes out at 48A (load management might not even be necessary)
• Find another charger with load management that can provide 60A or 80A
  • Pros: Would solve most of my problems (fast charging with overload protection for reasonable cost)
  • Cons: I'm not aware of any 60A or 80A chargers with load management

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?

Thanks in advance!

Charge overnight, problem solved. Should do a load calc, your prob ok

 

[Adventureboy]

I run the 48amp Emporia like others on the thread. It recharges my ER from 20-85% easily in my 8-hour low rate window. It keeps me running in the 180-200-mile daily range when needed.

Most of the time I have it set to 32 amps and only dial it up to 48 amps when I need to do back-to-back long driving days (maybe once or twice a month)

@RickLightning hit the exceptions.

 

[luebri]

IMO, there are only 2 reasons to use 80amps vs. 48amps:

1) You have a need to quickly replace energy during a 12 hour period on a regular basis, for another trip. Regular basis, because once in a blue moon wouldn't justify the expense of the heavier wiring and breaker.

2) You plan on installing the V2H solution (roughly $10K by the time you're done).

Otherwise, there's zero reason TODAY to go over 48amps.

Not disagreeing, just providing a scenario that could be applicable to some.

That scenario that has come up a few times for me, that can create a little more benefit to 80amps... Is if you are on time-of-use (and trying to control costs and avoid peak rate charging like the plague) which decreases your acceptable charge window at home. Furthermore, as a result this increases the likelihood you end up in a scenario where you might want/need to pump as many kwh quickly.

An example... the storms that nailed the midwest on Tuesday. I had actually been doing way more than my usual daily driving throughout the day and was at ~30% battery when I got home at 5 PM. Expensive TOU (~$.38/kwh) was in place until 7PM. It wasnt a huge deal for me (I have a generator) but I figured with mass area power outages a possibility with storms arriving around 9, it would be best to get as much charge into the battery as quickly as possible, but I still wasnt going to pay peak TOU rates to do it. I waited until 7 PM (mid tier rate at ~$.14/kwh) and was able to get ~35 kwh into the battery in a brief 2 hour window before the front edge of the storm hit, which did knock out power for a number of people in the area (luckily not me).

But in general I do agree.... it's still once in a blue moon. The blue moon just may appear more on time-of-use.

For me the FCSP was easy to incorporate to my 200a service and the FCSP came for free with my truck. So it was as easy decision, and it has definitely provided a benefit to have at times.

 

[RickLightning]

I sold my FCSP for $1,000. Got $500 per EV charger from my utility company. Load sharing two JB 48s.

 

[GDN]

I'd ask one question - do you need to charge the whole battery most every night? If not then I see no need for more than a 60 amp breaker and likely 50 would suffice for 98% of the needs. So 1 - Dump the Ford charger and buy one that you like, then 2- install it off of a breaker from the main panel at what ever the electrician determines it can handle up to 60 amps.

That is the reasonable way. If you think you might have a second EV and you would need to charge them both at the same time or you really want to future proof and you want the more expensive set up then go with the 100A load management.

I think upgrading to a 400 amp panel would would be expensive - 10K or more?

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