Utility Issues while charging

[Forebiz]

I've read the disappointing new that Ford will be discontinuing the Lightening. I bought the Lightening for myself but my wife has put probably 98% of the mileage on it because it just made more sense for her to drive it because she drives further and liked it. We both really like it.

I read many comments on the discontinuation and I want to point out that charging even at home has issues in terms of utility infrastructure.

We are in the city and the transformer feeding a group of 10 houses has been blowing fuses on the secondary since we got our truck. At first I thought it was mainly a summer issue related to AC units running but the last cold spell had the utility out 3 times because the fuse blew. We had opened up a case for the utility to investigate this further this last summer and their conclusion was the secondary fusing needed to be resized as it was not adequate. They had not done that yet but the last time the utility came out the service techs were told to remove the secondary fusing entirely. This is what I know.

-10 houses fed from 100KVA transformer (I think) this transformer might be good for just over 400A total.
-Secondary fusing was 200A slow blow fuse
-I think the feeders to branch pedestals are 4/0, each pedestal feeds 2-3 houses, ours is 2
-Without our truck plugged in when they replaced fuse initial load (cold weather) was 220A on one phase.
-With truck plugged in the next time they came the load was 320A, purposely left it on charger so they could see 200A didn't come close to cutting it.
-I believe we are the only ones that were charging their EV at the time. Two others in the 10 houses have plug in hybrids and I know one only ever plugs in to 120V 15A but wasn't home, don't know about other guy.
-The linesman said he'd never seen such a high load and only in couple times in his career have they removed secondary fusing using the wire itself as fuse.
-Our house has 200A service most others are likely 100-150A
-Neighbor who rebuilt house that burned down had to get their own transformer because they put in 600A service. Point being utility knows there are issues and will force new customers to pay for major equipment.
-When I noticed the neighborhood only got knocked out when I was charging we changed to charge only starting at midnight. Didn't help this last time as power went out at 12:30am.

Now I know their will be a lot of questions because I have them too the biggest being is it normal to have 200A secondary fusing feeding 10 house that have a potential demand of 2000A?

My main point is; if this is common practice among utility companies there is no way that half the population (maybe as low as 20%) could have at home chargers without major issues.

I don't want a vehicle with a generator but maybe we just aren't ready yet.

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[mr.Magoo]

I mean, there's houses and then theres mansions.

I'm not sure how you can see 220A on one phase/leg unless whomever wired your house forgot they had two ?
And even then it seems kind of high unless you have 20,000sqft and operates a growhouse, bitcoin farm and a outdoor koi pond in Alaska.

 

[RickLightning]

We have 200amp service, and share a transformer with one house. Utility said either we or they can upgrade to 400amp, with no upsizing, but the 2nd house will have to pay for a bigger transformer. I think it was $300 or so.

 

[Maquis]

Yes, that’s normal. Utilities push equipment to the limits and beyond. 99.9% of the time, there’s never a problem. When there is a problem, they adjust, just like they are doing in your case.

 

[Forebiz]

I mean, there's houses and then theres mansions.

I'm not sure how you can see 220A on one phase/leg unless whomever wired your house forgot they had two ?
And even then it seems kind of high unless you have 20,000sqft and operates a growhouse, bitcoin farm and a outdoor koi pond in Alaska.

220A was for all 10 houses, eventually when that blew again after starting charger it forced them back and then it was 320A while my charger was going. My house load was approximately 90A per phase with charger going.

 

[Forebiz]

I asked AI if three houses had 80A chargers under these conditions how many houses would you feed from 100KVA transformer. It came up with the following answer.

The 100 kVA transformer could typically feed between 1 and 4 houses (including the three houses with EV chargers), depending heavily on the average diversified load assumption (e.g., 5-8 kVA) used by the utility. The significant load from the EV chargers drastically reduces the number of additional houses that can be served compared to the typical 10-20 houses without such loads.

 

[mr.Magoo]

220A was for all 10 houses, eventually when that blew again after starting charger it forced them back and then it was 320A while my charger was going. My house load was approximately 90A per phase with charger going.

That makes a lot more sense.

But as others already pointed out, infrastructure improvements is a given as time progresses.
They didn't need four lane highways 100 years ago, now we do.

 

[Forebiz]

I think it was $300 or so.

Sounds like a deal. I would bet the investigation for the fuse size on our transformer and the numerous times to come and replace fuses cost the utility thousands. A transformer to feed 400A is going to cost significantly more then $300 especially installed. Your utility might eat that cost but mine won't.

 

[Forebiz]

That makes a lot more sense although your charger should only add about 40A per leg/phase if you're charging at the full 80A

Are you sure its 80A per leg. It hardly makes sense to require a two pole 100A breaker if it is only 40A. I've never measured it.

One thing I forgot to mention is that only one leg of our power ever drops out so we still have 120V for half the things in the house. It was quite cold and I know some neighbors lost their furnaces during this time so I'm sure there were space heaters galore plugged in on the plugs that worked in their houses. So yes I bet the jump in power was coming from neighbors as well. Not to mention any pool heaters or hot tubs that came back on once 240V kicked back in.

 

[Ragman]

It’s all based on percentage used, 99.9% chance all ten houses pull 200 amps simultaneously. All the way up the distribution pipe this is standard. Your particular scenario doesn’t make sense and likely breaks a bunch of codes - does not sound like everything wired in would have passed load calculations.

On charging people first have to get through the falisy people need 80 amp chargers at home. 30 amp / 24 actual is 6 kwh and fine for 99% of drivers. For the rest smart meters to limit power at peak times of day combined with off peak pricing solves rest.

The you need a bigger service/panel is a combination greed by electricians and scare tactics that the grid is falling due to evs.

 

[Forebiz]

First have to get through the falisy people need 80 amp chargers at home. 30 amp / 24 actual is 6 kwh and fine for 99% of drivers. For the rest smart meters to limit power at peak times of day combined with off peak pricing solves rest.

I agree with this.

I could turn my charge rate down but we paid extra for the 200A service. I get that just because I have a 200A service doesn't mean I get 200A and have been specifically told that it's sized for up to 75% of that (150A). I'm still drawing much less.

We have smart meters but the utility isn't yet using peak pricing. I wish they would.

 

[mr.Magoo]

Are you sure its 80A per leg. It hardly makes sense to require a two pole 100A breaker if it is only 40A. I've never measured it.

No, you're right brain fart moment.

 

[Heliian]

When people make claims that ev's will strain the grid they lack the basic understanding of how much electricity that industry uses. Household use is irrelevant. Your shitty service provider is the problem.

 

[chl]

Losing just one 120V leg issue:

Possible solutions short of the utility expanding capacity - maybe they would help subsidize doing these?

1) So one thing that could be done is for everybody using that transformer (10 houses) to balance their loads in their service panels. That is divide their loads as evenly as possible between two 120V legs.

The 240V service is two 120V Hots wrt the Neutral in the service panel, and each leg is distributed through circuit breakers to your house loads. The 120v breakers on one side of the service panel carry one leg and the 120V breakers on the other side the other leg.

The 240V breakers carry both legs.

When there is more load on one side's breakers (one leg), that is considered 'unbalanced.'
Being unbalanced has some negative consequences.
In your and your neighbors' situation one consequence is an outage on one 120V leg.

If the loads in each house were more evenly divided between the legs, that could avoid (probably) the one leg fuse blowing outages.

There are lots of articles about balancing the loads in your service panel.
When a home is first built, the electricians (in theory) will try to balance the expected loads.
However, as time goes on, people add circuits, devices, etc. often without paying much attention to balance.
----
2) Another thing everyone could do is get energy efficient appliances and lights as time goes on.
Especially appliances like refrigerators and hot water heaters.
Move to LED lighting.
Add insulation to the attic and crawl-space, install Energy Star gas filled windows, etc.

Not only will you reduce the demand on the utility you will save money over time.

When I switched to a hybrid-type hot water heater, it paid for itself in lower electric bills within 18 months.

Often utilities, state and/or local governments will provide incentives for energy saving appliances, etc. because it costs them more to expand capacity than to provide rebates.

If your area is suitable, install solar panels - the return on investment is a bit longer generally than the other energy saving modifications.

The DOE and EPA may still have resources/information on their web sites you could look at, if the nincompoops haven't taken it all down yet.

There are also private non-profit groups that can help like:

https://energycenter.org/about-us

 

[Forebiz]

The utility attempted to balance the transformer load on each leg by transferring loads right from the transformer feed. It makes sense in most cases that one fuse would blow before the other. Slow blow fuse. Even if both legs are over current once one blows the other is likely to drop as all 220V devices are then disabled or at the very least lose most of the load they were using.

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