The slippery slope of electrical upgrades - or help I'm still charging at 120V!

[Tronguy]

Couple of things.

First: There's this term, "Load Calculation". It's a standard thing that electricians do when sizing breaker panels. I believe that there's some calculators on the web, but it more or less adds up some data on square footage of the house, how many appliances of what kind (HVAC, microwave, electric stoves, electric driers, etc.) and comes up with a Number. Add to this the (nominal) 60A circuit you'd like to add for a HPWC.

The general idea is that a house, under normal usage, shouldn't be popping any breakers, especially the Main.

When the crowd that added my Wall Connector was contacted about the project, that Load Calculation was mentioned right off the bat. Now, it so happens that this house has a 200A panel, so it wasn't a difficult bit of messing about, but, still. Around here we've heard a couple of people mention that they needed a bigger panel, and they had a 200A panel.. but I guess it was a pretty big house.

Second: It's not just the size of the panel, it's the size of the drop from the power pole. These, too, vary in size and, if you end up needing a bigger panel, you may need a bigger feed from On High.

Third: I happen to live in the State of New Jersey, which is exceedingly big on BEV and everybody buying them. One of the many programs they have is to provide monetary assistance for not just putting in something like a HPWC, but separate funds designated towards the local utilities to increase the size of the drop from the pole. I'm not sure, but adding a bigger panel might be part of all the foo-fer-aw.

Fourth: After noticing all these various subsidies on njcleanenergy.com (no, really, that's them), I've had cause to check and see if other states are doing stuff like this. I've only checked a few (Maryland, MA, maybe one or two others) and, well, they are. Sometimes it seems like the subsidies are aimed at commercial properties (Virginia?) but others were very definitely aimed at consumers.

Fifth: Again, NJ is an electric-mad state. Many states (I'm aware of CA, as well) have PUC-mandated Special Deals where, if you're charging an electric vehicle, you get cheap charging rates on that. In fact, PSE&G, the local utility here, has, for Teslas at least, partnered with some company or other that, with the correct data, will talk to the Tesla Mothership to figure out how many kW-hrs one is spending on car charging. And to charge an exceedingly low rate for kW-hr's used for that purpose.

So, check for State stuff, especially if you need to upgrade your breaker panel/drop line.

Finally: Not sure about this, but paying Good Money to add stuff for Clean Energy gets 30% off from the Fed as a tax rebate. That's for solar panel systems, more efficient HVAC, and the like; but, if memory serves, upgrading your electric panel so you can charge your BEV may qualify. Check that, sir.

 

[timeshifter]

I'm in KY so I'm not sure there's going to be too many incentives for me. But the federal one might help

EV Charger Tax Credit: What You Need to Know

The federal EV charger tax credit for electric vehicle charging stations and equipment is back with a few key changes.

www.kiplinger.com

So I could get a 30% tax credit off the costs or labor and materials to install an EV charger in my garage? Wonder if I could claim the cost of the whole job since to properly install a charging station I'd need to upgrade my panel?

 

[Tronguy]

I'm in KY so I'm not sure there's going to be too many incentives for me. But the federal one might help

EV Charger Tax Credit: What You Need to Know

The federal EV charger tax credit for electric vehicle charging stations and equipment is back with a few key changes.

www.kiplinger.com

So I could get a 30% tax credit off the costs or labor and materials to install an EV charger in my garage? Wonder if I could claim the cost of the whole job since to properly install a charging station I'd need to upgrade my panel?

Do what I do when one sees something like that on some it's-not-the-IRS-web-site spot: Fire up the web browser, head to irs.gov, and look.

Maybe I'm just weird, but I've found that if one just reads the Blame English over at the IRS, one gets straight answers.

Kentucky, eh? One second...

Home :: KYTC

(But it seems to be about infrastructure, not sure what it means for homeowners)

EV Plan :: KYTC

(Again, seems to be about infrastructure, but it mentions local governments...)

Yeah, you're right, doesn't seem like there's anything direct for homeowners. Although there's an email address, [email protected], and you might drop them a line and ask.

FWIW, here's the link for NJ's Approach To Life on this front:

Electric Vehicle Incentive Programs | NJ OCE Web Site

njcleanenergy.com

 

[dafish]

i can only add I’m on 200 amps now and am tight. I regret not putting in 400 when I had the chance. I’m quite certain future EV’s will allow much greater density, and with it higher charging options. We already have 80amp EVSE’e, right?

And if you’re already over budget at 100?

 

[SalisburySam]

This is an interesting option. Did your cost per kWh change at all because of the 400 amp service?

No, we stayed on the same tariff as before. We get about 11¢/kWh or so. That’s including all fees, taxes, and other fixed charges in addition to the electrons themselves so will vary from month to month…lower per kWh cost in high demand months (summer) as fixed costs are amortized over a larger amount of variable ones. We have no time-of-use or other savings rates available, just an option to control A/C units for a small rebate during summer months. We’ve opted to not accept that.

 

[poundsand]

Couple of things.

First: There's this term, "Load Calculation". It's a standard thing that electricians do when sizing breaker panels.

This. No point in spending money for a 400amp panel to future proof if you're currently on a 100amp and well within limits on a 200amp panel and will likely never actually run into the limitations of that panel. We're in a 2500ft2 house, with central air, 2 electric ovens, electric dryer, 2 electric 80 gallon water heaters, 3 car garage, 3 small appliance circuits, central air, etc, on a 150amp service. The electrician did a load calc when installing 2 new circuits for EV (one for a hard wired tesla charger, and one for a 14-50), and we're still within limits on 150amps.

 

[Jeff-4]

Finally: Not sure about this, but paying Good Money to add stuff for Clean Energy gets 30% off from the Fed as a tax rebate. That's for solar panel systems, more efficient HVAC, and the like; but, if memory serves, upgrading your electric panel so you can charge your BEV may qualify. Check that, sir.

This site is helpful:

Household electrification incentives calculator from Rewiring America

Find out how much you could save with tax credits and rebates for heat pumps, water heaters, electric vehicles, electric stoves, rooftop solar, wiring upgrades, and energy efficiency improvements to your home.

www.rewiringamerica.org

 

[boulder.dude]

If going to 400A requires a new cable from the power pole, and your cable is buried, that it could be quite costly and disruptive?

 

[Tronguy]

If going to 400A requires a new cable from the power pole, and your cable is buried, that it could be quite costly and disruptive?

Yep. In NJ, anyway, if one is doing a bigger panel and a bigger drop so one can charge one's BEV, then the State, no less, will pick up the tab for the drop. Other states do so as well, but apparently not KY (but haven't done an extensive search, so who knows?).

 

[dakhlkt22]

i can only add I’m on 200 amps now and am tight. I regret not putting in 400 when I had the chance. I’m quite certain future EV’s will allow much greater density, and with it higher charging options. We already have 80amp EVSE’e, right?

And if you’re already over budget at 100?

This. No point in spending money for a 400amp panel to future proof if you're currently on a 100amp and well within limits on a 200amp panel and will likely never actually run into the limitations of that panel. We're in a 2500ft2 house, with central air, 2 electric ovens, electric dryer, 2 electric 80 gallon water heaters, 3 car garage, 3 small appliance circuits, central air, etc, on a 150amp service. The electrician did a load calc when installing 2 new circuits for EV (one for a hard wired tesla charger, and one for a 14-50), and we're still within limits on 150amps.

Good points, but just remember that we are at the start of a big shift towards electrical power. It's important to know what electricity prices are like in your state, if renewal energy is coming online in your state, and how likely you are to want to adopt other energy efficiency upgrades. It depends on the homeowner, but if they're that type of homeowner, they may also want to plan for the possibility of transitioning to heat pumps, heat pump water heater, heat pump dryer, solar, multiple EVs, induction stove, etc etc. Especially if they are not going to move anywhere, then it is very likely that every system in their house will eventually need to be replaced. When that time comes, that is a natural transition point to consider electric power. I am seeing this transition happening in my neighborhood. Heat pumps are popping up a lot. Ten years ago they were nowhere to be seen.

We're upgrading to 200A but it's a small house with a one car garage.

 

[dafish]

Boulder:

Yes and yes.

I would expect the 200 amp upgrade to as well. Just cheaper.

if planning for the present i suppose the next best alternative is to use dual WC’s and configure them to load share. This as if he’s overloaded already (as he’s reported), and wants to support dual EV charging. whatever he has remaining from the 200 amp service (obviously less than 100 amps), isn’t going to support dual 60a EV’s concurrently. much less future EVSE rates. dynamic load sharing would be the next best solution.

Future rates? Guess we‘ll see.

I can tell you we put a 200 amp panel in my sons garage explicitly to support EV‘s now and in the future. Couldn’t have done that without his 400a service.

 

[SalisburySam]

Yep. In NJ, anyway, if one is doing a bigger panel and a bigger drop so one can charge one's BEV, then the State, no less, will pick up the tab for the drop. Other states do so as well, but apparently not KY (but haven't done an extensive search, so who knows?).

No such luck in NC either.

 

[SalisburySam]

If going to 400A requires a new cable from the power pole, and your cable is buried, that it could be quite costly and disruptive?

To say the least. Your home may be able to get the upgrade with existing wiring but that has to be determined. You might also be able to pull new wire through existing conduit if you’re lucky. That wasn’t the case for me and larger wires were needed…the new trenching and conduit were just the place to put them.

By the way, it was fascinating watching how the electrician pulled the very heavy and stiff wires through about 75 feet of conduit buried 42” below grade. First of all, the conduit was laid in the trench with a small steel cable put into it as the pulling wire. At the open end at the power pole, two electricians were stationed, one who secured the steel pulling cable to the ends of the power wires and then pushed the wires into the conduit. While doing so the other electrician had a 5-gallon bucket of some sort of thick grease and was slathering it on the power wire insulation to reduce friction pulling the wires. At the other end was another person pulling the steel cable. The conduit had three gentle 90º curves to negotiate and this all worked well but there was a lot of huffing and puffing getting the uncooperative power wires to the home’s service entrance. After all home connections were made and the meter installed, the power company then connected the wires to the transformer at the pole. There is not enough money in the world to pay me to do this, and once again it was fascinating to watch people who know what they’re doing work quickly and accurately around untold amounts of killing live electricity.

 

[poundsand]

Good points, but just remember that we are at the start of a big shift towards electrical power. It's important to know what electricity prices are like in your state, if renewal energy is coming online in your state, and how likely you are to want to adopt other energy efficiency upgrades. It depends on the homeowner, but if they're that type of homeowner, they may also want to plan for the possibility of transitioning to heat pumps, heat pump water heater, heat pump dryer, solar, multiple EVs, induction stove, etc etc. Especially if they are not going to move anywhere, then it is very likely that every system in their house will eventually need to be replaced. When that time comes, that is a natural transition point to consider electric power. I am seeing this transition happening in my neighborhood. Heat pumps are popping up a lot. Ten years ago they were nowhere to be seen.

We're upgrading to 200A but it's a small house with a one car garage.

I'm all electric already other than the furnace and range top, and have the two EV drops for one ev. I expect any replacement appliances will be more, not less energy efficient. But regardless, get a load calc done - you can talk about potential future needs when doing that too... it's not like you need to only do it on what you have now.

 

[bradtem]

I am an investor in this company: Home | Variablegrid Adaptive Power Inc.
The home version of the product solves this. It's a small box which measures the energy being used by the rest of your house, and adjusts the current to the car to use what's left, within the code limits. It's mostly sold for multi-unit buildings but there is a home version which is not cheap but is much cheaper than any service upgrade.

Essentially the car will pretty much always get full power because most homes are overprovisioned. However, if in the middle of the night when your AC and dryer are on you turn on your oven, the car will get a bit less. In practice you never run all those things in the night.

With a tool like this there is generally never a need for a service upgrade as long as the local inspectors understand it. (The codes are starting to now understand smart devices and their ability to assure that current stays within limits.)

However, another solution for many people if they have a dedicated circuit to a 120v/15a plug is to swap it out for a 240v/15a circuit, keeping the same wire but changing breakers and socket. You must have a dedicated neutral as it will become a 2nd hot.

240v/15a is usually enough for anybody, it can replenish about 10mph which will get you full overnight almost all nights.

If that's not enough you can get the varian home. Sadly, it only works with OCPP supporting EVSEs, and the TWC does not support this standard, and the protocol to control a TWC 3rd generation remotely has not been reverse engineered yet.

 

[dakhlkt22]

I am an investor in this company: Home | Variablegrid Adaptive Power Inc.
The home version of the product solves this. It's a small box which measures the energy being used by the rest of your house, and adjusts the current to the car to use what's left, within the code limits. It's mostly sold for multi-unit buildings but there is a home version which is not cheap but is much cheaper than any service upgrade.

Essentially the car will pretty much always get full power because most homes are overprovisioned. However, if in the middle of the night when your AC and dryer are on you turn on your oven, the car will get a bit less. In practice you never run all those things in the night.

With a tool like this there is generally never a need for a service upgrade as long as the local inspectors understand it. (The codes are starting to now understand smart devices and their ability to assure that current stays within limits.)

However, another solution for many people if they have a dedicated circuit to a 120v/15a plug is to swap it out for a 240v/15a circuit, keeping the same wire but changing breakers and socket. You must have a dedicated neutral as it will become a 2nd hot.

240v/15a is usually enough for anybody, it can replenish about 10mph which will get you full overnight almost all nights.

If that's not enough you can get the varian home. Sadly, it only works with OCPP supporting EVSEs, and the TWC does not support this standard, and the protocol to control a TWC 3rd generation remotely has not been reverse engineered yet.

I totally get that most loads are not used concurrently, but aren't electricians required to do a load calculation based on how the code book tells them to do it? So it's not really discretionary, or is it?

 

[Tronguy]

I totally get that most loads are not used concurrently, but aren't electricians required to do a load calculation based on how the code book tells them to do it? So it's not really discretionary, or is it?

Um. That Load Calc, and the method used to do it, is straight out of the National Electric Code. Which, while not having read the thing, I'm pretty much certain is based upon the idea that there's no dynamic anything.

Look at it this way: If one adds up all the amperages of all the labels of all the breakers (not including the main) on any home breaker panel one might care to name, dollars to donuts that that amperage will be somewhere north of 1.5X the main breaker rating. Which in principle means that people could be popping the main on a regular basis.

But no house I've ever seen gets actually loaded that way. I mean, a standard vacuum cleaner is, what, 6A? And we plug it into a 15A circuit. So, get weird: Run down to Best Buy and wipe them out of vacuum cleaners and fill every third socket with one, turn on all the lights, turn on the HVAC, oven, microwave, garbage disposal, attic fan, and so on, and betcha you can make the main blow. And probably draw the attention of all the neighbors while one is at it.

The standard load calc likely has all sorts of margin built into it based upon people's actual habits.

Where things can go wrong is when one takes a marginal breaker panel (a brother of mine has one), then adds a 48A steady load to it, overloading the Load Calc number by 150% or something. Then one is likely to pop the main. In which case, something a good deal cheaper than a brand new breaker panel could keep things under control by limiting the potential overcurrent on the Main.

Like I said, the NEC is something I haven't read, but, from what little I've seen around here with people quoting it, I'd be highly surprised if there wasn't an "out" for this gear.

I mean: Results matter. If it's designed and actually works to keep the main from overloading, then that's what it does, which is the same thing the Load Calc has in mind.

 

[bradtem]

I totally get that most loads are not used concurrently, but aren't electricians required to do a load calculation based on how the code book tells them to do it? So it's not really discretionary, or is it?

It's debatable. The NEC is old but local codes can explicitly allow it. I believe where I am, the code has a specific exception for EV circuits which tend to have dynamic limits. At least my electrician seemed to think so, I haven't done a specific reading of the code. The code in Canada allows this (it is where the company is based.)

It is also, of course, the right thing. 20th century codes should be revised as soon as we can to make it easier to switch to EVs. The reality is a lot of homes have smaller service and can't install a high power EVSE if you just add up the breakers, and so electricians tell the customers they need a very expensive service/panel upgrade. This discourages people from getting EVs or putting in charging for them. If you can measure the load on the rest of the house, you can assure that the total load remains within the correct tolerances and breakers will not blow.

The truth is, nobody actually needs a service upgrade if this is done right. The code worries about what the load will be if the oven, AC, stove, dryer and car charger are all on at the same time. This actually never happens, especially at night, and if it were to happen, the car just draws a little less power during the period it is happening and still gets fully charged during the night.

This is even more important in condo/apartment buildings, where just adding up breakers will say you can't install more than a couple of EVSEs. In fact you can install one for every unit in the building if you want, and you will never need to draw more current than your current limit. In this case, if you have 20 cars in the parking lot, most of them only need 10kWh during the night, only a few will need more full charging. Managing the sharing and making use of spare power from the dwelling units can give you enough to do all you will ever need.