Solving the EV Home Charging Puzzle

One of the best parts of owning an Electric Vehicle (EV) is being able to charge it at home. In my day-to-day life I never have to go out of my way to ensure that my car is always topped-up and ready to go. I plug in at night when I get home and the car is always fully charged when I leave for work in the morning.

Do EVs Come with Home Charging Stations Included?

In the 2010s, when the modern era of EVs really began, figuring out where you were going to charge your new electric car was a huge concern. There were no public fast charger networks and finding a charger of any kind could be challenging. Providing home charging solutions was a huge part of the sales process to convince potential buyers that owning an EV was a viable choice.

Fast forward to 2024 when I bought my used Chevy Bolt EV and the world of electric vehicle charging is very different. As I write this, there are 16,925 CCS DC fast charging ports in the US and Tesla has over 36,499 NACS Supercharger ports installed. A major agreement was recently reached in the US and soon all major car companies will release their cars with the NACS charge port as standard and Tesla has begun to open their network to cars from other manufacturers.

Most EVs today are sold with an included portable charging cable*. This can be a level 1 charger that plugs into any 120v household outlet, or a dual voltage level 1/2 charging cable like the one that came with my Bolt EV*. But, Tesla recently moved to make a portable cable an option rather than standard equipment on their new vehicles. The need for a ‘just in case’ charging cable has become less important as their charging network has matured.

Home EV Charging Options

When I drove my 2020 Chevy Bolt EV home for the first time, I didn’t have any other charging options available at home beyond the portable charge cable* that came with the car. I had intended to purchase a home charging station fairly quickly, but discovered that the level 1 charging from a regular wall outlet provided enough electricity overnight to keep the car topped up all week long. So, I didn’t have to rush out and invest a lot of money installing a charging station.

Using a portable charge cable that plugs into either a 120v outlet (level 1 charging) or a 240v outlet (level 2 charging) is the simplest way to get started charging at home. But a dedicated home charging station* comes with a number of benefits.

One of the first benefits of a home charging station is that they will let you charge at a higher speed than a portable charge cable. Portable level 2 charging cables tend to max out at 16 amps for safety reasons. An EV draws a large amount of current over a long period of time when charging. To prevent the overheating of wires and electrical components, a charger should never use more than 80% of the available amps on an electrical circuit. To prevent an accidental current overdraw, portable cables are designed to limit the amount of current and leave plenty of safety margin. Charging stations are intended to be installed on a dedicated electrical circuit, so they can take the maximum advantage of the available electrical supply. A 48 amp charging station* connected to a 240v 60 amp dedicated circuit can provide 11.52 kW to the car for charging. That’s enough to charge my car from 0-100% in under 6 hours.

Home charging stations come with benefits beyond being able to provide more power. They are also designed to be securely and permanently mounted to a wall or mounting pillar. They usually include an integrated cable and plug holder to securely store the charging cable and protect the plug when not in use. They also usually have the option of a plug or hardwire installation.

Lower end charging stations might provide little beyond the cord and a place to hang it, but many home charging stations include wifi connectivity that lets you monitor and control the charger through an app. For the data geeks, you can track detailed energy usage over time and program your charger to only supply power during off-peak hours to reduce your electricity expenses.

If you are a multi-EV household, there are even dual port home charging stations like the Enphase HCS-D50* that will allow you to plug in 2 EVs at the same time and either split the available power between both cars or charge one and then automatically switch over and charge the other when the first one is finished. There are additional electronics in this unit that allow 2 vehicles to charge off of one electrical circuit without overloading the wiring.

The newest chargers hitting the market are bi-directional charging stations. Some EVs (particularly electric trucks) are now shipping with technology built in that lets them send energy from the battery back through the charging station to provide power to your home. This can be used to provide back-up power during outages or integrate with a home solar power system.

The Cost of EV Home Charging Stations

The simplest home charging stations have an equipment cost of around $400 USD. As more features are added, the price goes up. Units with integrated monitoring and control apps that connect to your local WIFI cost closer to $600 USD, and dual charger systems usually cost several thousand dollars thanks to the extra electronics required to manage the load balancing between cars.

Bi-directional chargers are still fairly new, so they are particularly expensive at the moment. Ford’s Charge Station Pro is a bidirectional charger, but only works to send power from the vehicle when combined with Ford’s home integration system. This consists of a 10kW bidirectional charger, monitoring equipment, energy meters and a transfer switch to enable grid isolation during a power outage. The whole system can cost $12k-$15k.

Equipment costs are only part of the equation. You may be tempted to DIY your charger installation, but adding high amp 240v outlets is not the same as installing an extra plug in the bedroom. Choosing the wrong receptacle or improperly torqueing a connection can lead to overheating, shorting, and fires. Always hire a licensed electrician trained in the installation of EV chargers to handle the work. Also, if you live in an older home, you may need to upgrade the electrical service to your home to provide enough power to handle the extra load of EV charging. A simple installation might run $1,500 USD, but it cost me $15,000 to relocate the service panel in my older home and upgrade it to 200 amp service (this was part of a repair project done before I ever thought to purchase an EV.)

What I Chose to Install

As I previously mentioned, I started my EV ownership adventure with a level 1 portable charging cable hooked up to an existing outlet in my carport. This was enough to keep my car charged up during the week if I plugged it in every time I came home. I did just that for about two months.

My local utility company offers an EV charging rebate for charging at night along with rebates for installing an EV charging station. With level 1 charging I wasn’t able to keep the car fully charged if I limited it to off-peak hours. My desire was to invest in a 48 amp charger and hire an electrician to install a 240v 60 amp circuit. The rebate available would cover about half the costs involved.

I decided to wait on the installation of the charging station. My portable charging cable is dual voltage and will provide 3.84 kW to the car at its maximum capacity. There was an unused 240v 30 amp electric clothes dryer outlet in my carport and I decided to use that and my portable charging cable to handle my home charging. I use 10-15 kWh of electricity or less on an average day. At level 2, my portable cable can recharge my battery in 2.5-4 hours easily.

The outlet needed to be moved to a location closer to where I park my car, but the cost to do that was modest since all of the areas where the wires were routed were easily accessible. It only cost a few hundred dollars. My charger only draws 53% of the total amps available on the circuit, so I have lots of safety margin in the system.

Now, I am able to constrain all of my daily charging to the time of day when my electricity prices are lowest. There isn’t any urgent need to install a more robust system unless we get another EV or I just decide I just want to upgrade the system