EV Home Charging: The Good, The Bad, The Ugly

[G. David Felt]

The grand plan was a separate new service to the house of 200 amps so that the garage would have plenty of power for charging multiple EVs and I would have a separate bill each cycle for knowing what I was spending for EV driving.

Waking up in the morning to a full charge of power and never having to stop at a gas station due to having a Level 2, 240-volt home charger is a luxury everyone should have allowing you to smile as you drive by a gas station with folks outside dealing with their fueling. The ultimate perk of EV ownership.

 I started with reaching out to my local utility and inquiring of the process for a new service. My local utility was more than accommodating in helping me out with the details. As an engineer that loves to learn, this process was very eye opening into the costs, lack of efficiencies by agencies and electrical contractors with a surprising ending to my eventual solution.

Let's start off by making one thing clear, every state has their own regulations in regard to electrical. While the USA follows the national electrical code as a starting point, each state, county and city then adds their own additions or subtractions to the code. Always make sure to follow your local code no matter if you hire a company, independent contractor or are a DIY (Do it Yourself) type of person.

Full information on the national electrical code can be found here: 
The National Electrical Code (NEC) - Electrical Safety Foundation (esfi.org)

Another thing to point out is every state has their own way of dealing with electrical supply and competition. As such, some states allow their end users to pick among competitive electrical suppliers even to the point of choosing to use Green Energy (Solar, Wind, and or Hydro) or not (Coal, Natural Gas, Nuclear). Other states tend to regulate this down to the city and or county within a state.

Washington state is a regulated power supply state so that depending on the county you live in; you deal with your county or the state power supplier. Washington state has one of the greenest electrical grides in the country. It produces 7,816 MWh of electricity and it breaks down as follows:
Figures as of May 16th, 2024

• Petroleum-Fired - 0%
• Natural Gas - 21.3%
• Coal-Fired - 3.9%
• Nuclear 10.3%
• Renewables - 64.1% (Hydro, Wind, Solar & Ocean)

Fueling Stations in Washington State:

• Motor Gasoline - 1,846 Stations
• Propane - 64 Stations
• EV Charging - 2,153 stations
• E85 - 5 stations
• Biodiesel, CNG, & Other Alternatives - 8 stations

If you wish to check out your own state information you can do so here by clicking on your state: 
U.S. Energy Information Administration - EIA - Independent Statistics and Analysis

Starting off on my project I had decided to go ahead with a ChargePoint+ Home Flex Hardwired solution. Yes, there are a wide variety of good home chargers that run from $250 to $2000 dollars such as the Porsche home charger.

Home Flex Hardwired Level 2 EV Charger (chargepoint.com)

The choice of this charger was based on the following:

• Some of the best reviews out there by thousands of people
• Hardwired allowed me the best power supply available to the EV building in future protection as newer EV tech comes online.
• ChargePoint sells both CCS and NACS supply cords, making upgrades from my current EV with CCS to a future EV with NACS easy as a self-Upgrade to the charger.
• ChargePoint app allows for use both at their fast-charging network and to track my own use and cost.

You can find a large diverse choice of L1 and L2 chargers on Amazon or from other sources. Many utilities will have rebates if you purchase through your local utility or in the case of my own system, I had to file a rebate form as my charger was on the approved list, but not available from my utility. ChargePoint+ also points out that till 2032 you might be able to qualify for a $1,000 rebate from the federal government.

Electric Vehicle (EV) Charging Incentives | ChargePoint

Now that I have covered some of the basics about electrical and power source, lets dive into my journey for a Level 2 Home Charger.

Karl at the Snohomish PUD sent me a form that I had to fill out, this was a "New Service Residential Request" form. Here I had to fill out the normal details such as my house address, current status of the electrical to the home, type of new service being requested, pictures of where the service would need to be connected to the house and where I wanted the service panel to be, etc. This form had an area for requested measurements from the house to the utility pole, gross measurements of where the wiring would need to go so that the service could be sized up accordingly. The last part was the direction from my PUD on checking with the city for any additional requirements.

For those wanting to see what the new service request form looks like I supply it here:

1097R_NSQres.pdf

City requirements were that any electrical changes to the existing structure that comprised more than 10% cost of the home improvement value as assessed by the county required that the electrical lines from the utility pole to the house be installed underground rather than overhead. Luckily for me, my estimated costs would be under this so I was not looking to have to figure this into the cost of adding the service or so I thought.

Karl at SNOPUD said he would do the assessment and have out to me the updated info shortly. In the meantime, I reached out to a couple of recommended electrical companies from the SNOPUD website and a few independent electricians to get estimates on the work to be done. Specifically, I wanted two quotes, first is the all-new service added to the house with dedicated panel feeding the garage. Second was updating the existing panel to support a charger in the garage using my existing service.

Here I was expecting a $5 to $6 thousand dollar install connection for the first service and based on the auto industry estimate of around $1,500 to $2,000 for the second. Boy was I off by a bunch. All the estimates from both the electrical companies I contacted, and the independent contractors had the new service install between $10 to $12 thousand dollars and the existing services was between $4,700 to $6,200. This also did not include the connection to the PUD. Here I was informed from Karl at SNOPUD that the service could be done but would require a new transformer to our cul-d-sac to support the added amperage pull. As such, this was more than just a wire connection but an outage to the cul-d-sac ending in an almost $15,000 charge. Who knew that adding a service where you pay them for the flow of electricity would have such a huge cost and impact on my project. This put the cost of a new service between $25,000 to $27,000 dollars. So much for the Auto Industry estimates of $1,500 to $2,000 dollars and it also did not include the required $125.00 electrical permit I would have to get from the city and inspection.

I did keep in mind that the price of electrical work varies based on the cost of labor where one lives, power of the charger, distance from the charger to the electrical panel along with the job complexity.

What about DIY (Do it Yourself), could I do this job myself and what would the cost be? First, I knew from all the quotes that I was greatly under my 200-amp service pull as I have Gas stove, Dryer, Water heater and Furnace. As such, the 240V 30-to-50-amp circuits that are in my panel are not being used at all. One of the independent electricians had stated that the cheapest way would be to pull an existing circuit breaker and run the wire into the panel with the new Circuit breaker, but most electricians did not like leaving existing wires from outlets in the panel even if they were sealed off, they just did not like doing this, so everyone had quoted based on adding a secondary panel.

With this information, I researched from the ChargePoint+ website on installing the hardwired charger I had purchased from them. ChargePoint+ has installation videos and covers all the information on installation as well as becoming a certified installation expert.

ChargePoint Home Resources | ChargePoint

ChargePoint Home Flex (CPH50) Hardwired Installation Video | ChargePoint

Become a Certified ChargePoint Installer | ChargePoint

From the website above I gathered the following information on the materials that I would need.

• Conduit large enough to hold the wiring
  • Brackets to attach the conduit and screws
• 90-degree wire access conduit
  • Associated pipe nipple for connection into the panel
  • Insulated bushing
  • Appropriate washer and locknut for connection to the panel
• 6 AWG wiring
  • Black, Red and Green wires per code
  • ChargePoint+ clearly states to use 6AWG for their Level 2 Charger installation.
• 6 AWG wire stripper
• 70amp circuit breaker
  • Some states require these to be Arc or GFCI for indoor or outdoor, national code for outdoor installation is a GFCI breaker upstream from the outdoor installation. Check local regulations for proper type required.
  • Make sure to get the proper type of circuit breaker for your panel, I had D block circuits.
    • 
  • Ground Fault Circuit Interrupters vs. Arc Fault Circuit Interrupters - Bob Vila
• Torque Screwdriver set
  • Most do not know that depending on the size of the circuit breaker, when you connect the wiring to the breaker, the screws must be torqued to a certain range. The 70amp circuits per the side of the breaker states 45 in. lbs.
• Paintable caulking to seal both access points into the house for the charger.

With having my list of materials, I choose to first compare prices online from Home Depot and Lowe's. What I found was that Home Depot was much higher in the cost of the wiring, but cheaper in conduit, circuit breakers and accessories. Lucky, I have both home improvement stores within a 2-mile radius of my house. What I also noticed was that neither home improvement store had the required tools I would need, so clearly, I would have to stop off at my local Harbor Freight tool store.

Harbor Freight Tools | Quality Tools, Lowest Prices

With the knowledge of what I needed and a shopping list, I headed out and accomplished the following:

• Electrical Permit from my city. 
• Wiring from Lowe's - Lowe’s Home Improvement (lowes.com)
• Conduit, circuit breaker and accessories from Home Depot - The Home Depot
• Tools from Harbor Freight tools company - Harbor Freight Tools | Quality Tools, Lowest Prices

Opening up the electrical panel as you can see here, I have my household 200amp circuit at the top. This will kill power to everything in the house, below this was the kitchen and laundry room 240V circuit and then on down throughout the rest of the house to the garage with various circuits.

At this point, I knew that I would be turning off the 200amp circuit to work on this panel and protect the rest of the house. Note to point out is that when you turn off this 200amp circuit, the power is not flowing to the rest of the panel, but you still have the power coming from the street to this panel and so there is live electricity in that 200amp circuit. One must always be cautious when working with electrical.

One safety thing to do, remove ALL jewelry, watches, phones, etc. Have nothing on you that is electrical or any kind of metal and that includes a wedding ring. All these are places that can cause an electrical jump / short that can cause you harm.

As one that grew up working on auto's and having great respect for the electrical system of auto's, homes, datacenters, etc. there are some things that I do not have a problem doing. In this case I kept the power to the house on while I pulled the panel cover off. A proper panel should have all the wires in 90 degrees to the circuit breakers and to the grounding / neutral bars that are silver in this case. Here I have not had any manipulation of the box done with patchwork electrical hacks. It is always best to learn the details or hire the proper person to do your electrical work.

Being that I am comfortable with pulling out the circuit breaker that is turned off, I choose to pull and replace the 240V 30-amp laundry room circuit. Here in this picture, you can see it removed and a better view of the grounding / neutral bar of the electrical panel.

At this point, I wanted to pull out the punch of where I was going to run the new electrical lines into the panel. Once I pulled out the punch, I drilled a small starter hole from the inside to the outside so I could line up properly the larger drill bit for the incoming conduit. Upon drilling, I attached the pipe nipple extension to the 90-degree wire access conduit, and I inserted it through the outside wall. Here I put on the washer, lock nut and insulated bushing as you can see here.

Now the next step was to install the conduit, some love their hard conduit and gluing it together as it comes in 10ft lengths, and you then have to either use a special heater tool to bend the hard conduit or buy the proper pieces that are curved. I choose to go with liquid proof flexible commercial conduit. The benefit here is that while this is a bit more expensive, the flexibility of the line makes it so much easier to install. One thing no matter what type of conduit you choose to use is that one has to run the electrical lines through the conduit. Hard conduit can be with tight bends very challenging to run the electrical lines unless you have a special tool that allows you to snake through the conduit, attach the electrical lines and then it uses an electrical motor to pull it.

I choose to run my flexible conduit out in a straight line, and I had pushed through my three 6awg lines through it so that I had the wire already in the conduit. Now this does make the conduit much heavier to install, but I found it faster and easier to do it this way. You will also notice that I have a Black, White and Green wire rather than the code dictating a Black, Red and Green wire. Both Lowe's and Home Depot were out at the time of purchase the red 6awg wire. So, I did what is allowed and that is on the ends of the wire at both ends, I wrapped them with red electrical tape.

I started with connecting the liquid tight end connector to the flexible conduit and attaching it to the 90 degree wire access to the panel. I pushed the wires through to the inside and reattached the liquid tight cover and then started using the brackets to attach the conduit to the house.

Two things to consider, one is the over all look of the installation, sometimes the cheapest approach is not the best especially when it comes to ones significant other, wife, partner, etc., not everyone likes to see conduit. I choose to do my best to minimize the visibility of the conduit and once I paint it to match the house it will truly not show up as the wife never noticed it when she came home till after I showed here.

Upon installation of the conduit with the 6 AWG wires, it was time to mount the home charger in my designated place. Here you need to make sure it is level, supported by the wall which can sometimes require additional bracing. Here you see my ChargePoint+ unit being installed on the wall.

With the charger installed onto the wall, I finished up the connection of the conduit / wires into the unit. Connected the electrical supply side and the charging cable side and reinstalled the cover.

With the installation of the charger unit and wiring done, it was time to focus on the circuit breaker installation side. Here I had an LED head light as I finally turned off the 200-amp circuit breaker to the house. I attached the red and black wires to the circuit breaker, installed the ground wire and then installed the circuit breaker into the panel. I also at this time wrapped each wire from the laundry outlet in proper electrical tap and a wire twist to add additional protection and secured them out of the way in the panel corner. I also at this time used my torque screwdriver to ensure proper torque on the wires.

With the installation completed at the panel side, I turned back on the 200-amp circuit enabling the house to have power and was time to go enable the charger unit. Here ChargePoint+ has an outstanding cellphone app to enable you to finish up the setup of the charger. I was able to connect to the unit via WiFi and set the unit to 70 amp circuit hardwired. I also then connected it to my house WiFi for internet access. This allowed me to do a update on the unit for software. Here ChargePoint has on the left side of the unit indicators for WiFi connection.

Green is good and as you can see in the picture above, I have WiFi connection and the alert is showing green so no issues with the charger. Upon using the regular ChargePoint software app on my smartphone I was able to complete setting up an account and final configuration of my charger as a home charger unit.

The unit is green when not in use but ready to be used. During Charging the unit is a pulsing blue.

At this point, I had a functional Level 2 240V 50amp hardwired home EV charger with CCS connector.

What did this cost me, simple a total of $1,032.23

Level 2 ChargePoint+ Home Flex hardwired charger: $549.99 plus $54.99 sales tax before $200.00 rebate.
Total Cost of Materials: $391.77 which was from Home Depot & Lowe's.
Tools bought for the job: $110.48 which comprised of a 6 AWG wire striper and a Torque Screwdriver set from Harbor Freight.
Electrical Permit: $125 from the city.

Best part of this is the cheap charging we get at home at .10 cents per kW. The ChargePoint app allows me to track and monitor in real time our costs and amount used, so it will make it easy to subtract it from the electrical bill to see the house use versus the EV.

The app shows that I am constantly at the 11kW controller capabilities of home charging from Kia.

This brings me back to why I titled this the Good, Bad and the Ugly. New Service request is the ugly as the costs of the new service from my power supplier has costs that have never been talked about before to me and I still have to pay for the electrical use which makes this the ugly when you are looking at a five figure cost. The bad is clearly adding the new service panel and the associated costs to an electrical company to do the work, pretty much double what the auto industry has stated having a Level 2 home charger installed would actually cost. Good is for those of you who are willing to learn and do the work, a DIY install is in my humble opinion a very cheap way to go even though it did take a chunk of my time, I have no regrets about learning the process to install and dealing with my city on installation.

End result is a quality home charger that will serve me well for many years.

Please post any questions or comments, happy to respond on this personal journey into home charging of my EV.

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[ccap41]

Great writeup, David! It's much appreciated.

On your screenshot of "Charging Activity" Is that the miles driven between those dates? 

So, you drove 265 miles from the 5th to 10th and it cost you $9.22? Am I reading that correctly? And at 0.10/kw that's about 92.2kw used from the two dates? 

What percentage do you charge to at home? Are you charging to 100%? 90%? 80%?

[G. David Felt]

20 hours ago, ccap41 said:

Great writeup, David! It's much appreciated.

On your screenshot of "Charging Activity" Is that the miles driven between those dates? 

So, you drove 265 miles from the 5th to 10th and it cost you $9.22? Am I reading that correctly? And at 0.10/kw that's about 92.2kw used from the two dates? 

What percentage do you charge to at home? Are you charging to 100%? 90%? 80%?

Yes, that is correct, the miles between charging that has been driven by my wife.

Correct, on your 265 miles statement.

We are charging almost 100% at home as unless I go on a road trip, there is no need for local fast charging at this time since we can just come home plug it in and the next morning before my wife leaves, she has a full battery pack. So other than the Electrify America Charging in Yakima that we did when we went for cherries two weeks ago, all charging is at home.

[ccap41]

On 6/22/2024 at 11:53 AM, G. David Felt said:

We are charging almost 100% at home as unless I go on a road trip, there is no need for local fast charging at this time since we can just come home plug it in and the next morning before my wife leaves, she has a full battery pack. So other than the Electrify America Charging in Yakima that we did when we went for cherries two weeks ago, all charging is at home.

No, I meant what state of charge are you charging to at home? Do you charge overnight to 100% battery? Or do you have it set to like 80% as to maintain the life of the battery? 

[G. David Felt]

2 hours ago, ccap41 said:

No, I meant what state of charge are you charging to at home? Do you charge overnight to 100% battery? Or do you have it set to like 80% as to maintain the life of the battery? 

I am not worried about the battery life and so we charge to 100% each time and life is fine.  Kia does not state the 80% thing of Tesla and others. They are saying you are fine charging to 100% if you daily driving the EV. The only note is a statement in their online document that if you plan to have the EV sit they do not recommend having it fully charged at 100%.

[surreal1272]

2 hours ago, G. David Felt said:

I am not worried about the battery life and so we charge to 100% each time and life is fine.  Kia does not state the 80% thing of Tesla and others. They are saying you are fine charging to 100% if you daily driving the EV. The only note is a statement in their online document that if you plan to have the EV sit they do not recommend having it fully charged at 100%.

Kia's own website says something quite different. Their batteries are not unique in the way that you are implying. 

2. Minimize the batteries at 100% state of charge

Electric cars already have installed with a battery management system that avoids them being charged and discharged at the extreme state of charge. Keeping the state of battery charge, from 0 percent to 100 percent , also improves the performance of the battery life of your vehicle. Even though a full charge will give you the maximum operating time, it is never a good idea for the overall lifespan of your battery.

 

3. Avoid using fast charging

If your batteries are soon-to-be die out, using a fast-charging is a great convenience. However, it presses so much current into the batteries in a short period which strains your EV battery and wanes them faster. While it is hard to notice its degradation, eight years of standard charging will give you 10% more battery life compared to 8 years of using fast charging.

 

4. Control the optimal battery state of charge during long storage

EVs that are parked or stored with an empty or full battery also degrades the battery. If you do not use your electric car often or having a long trip plan, get a timed charger, and plug it in. Leaving your vehicle at 100 percent while parked at a certain place for a long period, the battery will struggle with preserving its state of charge while you are away. One strategy is to set the charger to keep the charge just above the low mark, not filling it up to the maximum capacity, at an average charge level between 25 percent and 75 percent.

 

Source: 

 

https://www.kia.com/dm/discover-kia/ask/how-to-extend-ev-battery-life.html#:~:text=Minimize the batteries at 100% state of charge&text=Keeping the state of battery,overall lifespan of your battery

[ccap41]

42 minutes ago, surreal1272 said:

Kia's own website says something quite different. Their batteries are not unique in the way that you are implying. 

 

2. Minimize the batteries at 100% state of charge

Electric cars already have installed with a battery management system that avoids them being charged and discharged at the extreme state of charge. Keeping the state of battery charge, from 0 percent to 100 percent , also improves the performance of the battery life of your vehicle. Even though a full charge will give you the maximum operating time, it is never a good idea for the overall lifespan of your battery.

 

3. Avoid using fast charging

If your batteries are soon-to-be die out, using a fast-charging is a great convenience. However, it presses so much current into the batteries in a short period which strains your EV battery and wanes them faster. While it is hard to notice its degradation, eight years of standard charging will give you 10% more battery life compared to 8 years of using fast charging.

 

4. Control the optimal battery state of charge during long storage

EVs that are parked or stored with an empty or full battery also degrades the battery. If you do not use your electric car often or having a long trip plan, get a timed charger, and plug it in. Leaving your vehicle at 100 percent while parked at a certain place for a long period, the battery will struggle with preserving its state of charge while you are away. One strategy is to set the charger to keep the charge just above the low mark, not filling it up to the maximum capacity, at an average charge level between 25 percent and 75 percent.

 

Source: 

 

https://www.kia.com/dm/discover-kia/ask/how-to-extend-ev-battery-life.html#:~:text=Minimize the batteries at 100% state of charge&text=Keeping the state of battery,overall lifespan of your battery

I'm glad you found this because I had never heard charging to 100% didn't negatively affect a battery's lifespan. 

[surreal1272]

2 hours ago, ccap41 said:

I'm glad you found this because I had never heard charging to 100% didn't negatively affect a battery's lifespan. 

Me either (never heard) because there is no such thing as it being okay to constantly charge any EV battery to 100%.

Edited June 25 by surreal1272

[Drew Dowdell]

So, two things:

1. Consistently charging to 100% on fast charging is where most of the damage happens. He is slow charging at home, so this isn't an issue.

2. Holding the vehicle at 100% for extended periods of more than a few days also causes damage.  If the vehicle gets L2 charged to 100% overnight and then is used for commuting every day, there are very few negative effects.

That said, two other things:

1. Letting the battery go towards zero is good for the battery and the software calibration.  It won't harm things if you don't, but doing so keeps your range estimates accurate.

2. Those with short commutes do not need to charge daily on long-range EVs like this. Yes, it's neat that you can start every day at 100%, but each charge cycle is still a cycle, and there is an upper, though undefined, limit on the number of charge cycles the battery will take.  Taking a more ICE-like approach of only charging when needed will extend battery longevity. Plugging it in only every few days when the SOC gets to ~20% is fine. Of course, if you know you have a longer trip coming, fill it up ahead of time just like you would with a gas car.

[Drew Dowdell]

Of course, all that goes out the windows on vehicles with LFP batteries, which are only standard range Teslas at the moment.  But Ford and others will be using LFP for the next generation of low(er) cost EVs they plan to release. With LFPs, you can pretty much do whatever you want with regard to charging. They don't degrade from L3 charging as NMC batteries can. They don't mind being at 100% for extended periods. However, they don't have the energy density for long-range installations, so they'll likely end up being used in lighter and cheaper vehicles to counteract the range deficiency. 

To maintain the same range, an LFP in the Kia EV9 would need to be roughly 30% larger, and there likely isn't room for it. 

[G. David Felt]

Have to say that we love our EV9. Wife came home last night with 54% on the battery pack and plugged it in to have 100% in the morning as she informed me, she needed to run up north to deal with my side of the family and then down south to deal with her side of the family about 250 miles of driving. Plug in the L2 charger and let it charge up overnight. No running out to the gas station.

Kia own battery group has conflicting info on charging and maximum usage compared to their auto site.

@surreal1272 Thank you good info, had not seen that, but then did not look there compared to their battery division.

Also knowing that Kia / Hyundai / Genesis has different batteries from LFP to Solid State coming online in 2026 and 2027 this was why Leasing made sense to me, I am looking at 3 years only before trading it in on a new EV. Wife is averaging 150 miles a day driving, usually she waits till it is down to mid-teens percentage before plugging in at home for charging.

Overall, EV experience for us has been positive and I am hoping to add the EV9 Pickup as a replacement to my Escalade next year. Pretty much averaging charging every 5 days or so right now, once our new grandson gets a bit older and the other grandkids are out for the summer, next week it begins, my wife will not be driving as much in going to help with daily getting the kids to school and helping out. This can mean that I can see her going to only charging every 7 to 10 days then. We will see.

[G. David Felt]

Excited for the Pickup which you can see is in the GT blue with the EV9 headlights and other pieces.

[Drew Dowdell]

2 hours ago, G. David Felt said:

Kia own battery group has conflicting info on charging and maximum usage compared to their auto site.

That's likely the difference between the marketing people's wishful thinking and the engineering people's reality. While energy densities may vary between NMCs, the basic chemical reactions do not. All NMC batteries will have similar degradation profiles within the margin of error of different charging and usage profiles. Much of this particular battery chemistry advancement is done unless some headline breakthrough comes about.