Real-World Home EV Charger Performance: What to Expect

If you own or plan to purchase an EV, there’s a good chance you’ll want to charge it at home. For that, you’ll likely choose to install a Level 2 home EV charging station. However, you may have difficulty figuring out how quickly a home charger will charge your vehicle. It’s a more complex question than you migh think. Factors such as your EV battery capacity, charger type, driving habits, and your home’s electrical system all play a role. To explain this, here’s everything you need to know about home EV charging and the performance you can reasonably expect from a home charger.

The Difference Between Level 1 and Level 2 Charging

You can choose from two distinct types of home chargers. A Level 1 charger lets you plug your vehicle straight into a standard residential outlet to charge. While convenient, this is the slowest charging method available. It can add only around 5 miles of range per hour to the average EV.

A Level 2 charger is much faster than Level 1 and should charge the average EV within 10 hours. That translates to roughly 32 miles of range added per hour. For installation, Level 2 requires a dedicated power circuit in your home. Black-Haak provides professional EV charger installation in Greenville and the surrounding Fox Valley communities.

What ‘Miles of Range per Hour’ Really Means

If you’re wondering why we keep referencing the number of miles of range that a charger adds per hour, there’s a simple reason. If you’re accustomed to gasoline-powered vehicles, ask yourself this: When you go for a drive, do you try to estimate how many gallons you have left in the tank? Or do you worry about whether you’ll reach your destination before you need to fill up?

With an EV, it’s far more useful to think of range than battery charge percentage. The former lets you plan your driving day, while the latter provides no useful real-world information. Therefore, knowing how many miles of range your charger can add in an hour is the more useful metric.

Why Battery Size Affects Charging Time

As you may expect, the size of your EV’s battery will affect charging time as well. To understand that effect, you need to know that EV charge times aren’t linear. As a battery charges, internal resistance grows. In some cases, that means taking your battery from empty to an 80% charge takes less time than taking it from 80% to 100%.

The larger the battery in your EV, the more you’ll experience that effect. It means that you’ll add plenty of range to your EV’s battery in a relatively short time. However, if you want it to have a full charge, expect it to take much longer.

Your Car’s Onboard Charger Matters, Too

The charging interface inside your vehicle affects charge times, too. Whenever you plug a charger into your vehicle, its onboard computer will negotiate a connection with the charger. The two devices will determine their safe maximum charging voltage based on the hardware involved. In practice, that means your EV might never charge at the maximum rate your Level 2 EV charger supports.

Electrical Panel Capacity and Circuit Size

Since a Level 2 home charger needs its own dedicated circuit, your home’s electrical system directly impacts charging times. The majority of today’s Level 2 chargers operate at between 40 and 48 amps. So, your home will need a 50- or 60-amp dedicated circuit to support one. If your panel or incoming electrical service can’t support that, you’ll need an electrical panel upgrade. A licensed provider of residential electrical services can evaluate your available capacity before installation.

Why Charging From Empty to Full Is Not the Usual Scenario

Few EV owners charge their vehicles from zero to 100% daily. Flat-out charging speeds are far less critical than you may think. Most of the time, you’ll only be topping off your EV battery overnight. So, the factors that influence home charging times probably won’t affect your day-to-day charging experience.

Real-World Charging Expectations for Overnight Use

If you install a modern Level 2 home EV charger, you’ll likely begin every day with a full or near-full EV battery. Since you can use one to charge the average EV’s battery from zero to 100% within 10 hours, the overnight hours offer ample charging time. For example, even with a near-empty EV battery, plugging in at 9 p.m. would still leave you ready to go with a full charge by 7 a.m.

How Weather Can Affect Charging Speed

The only charging factor you can’t control at all is the weather. Both extreme heat and extreme cold will noticeably slow charge times. That’s down to battery chemistry, and it’s unavoidable. Some newer EVs will preheat or precool their batteries to mitigate those effects, but that uses power, too. If you have your EV charging in an uninsulated garage, expect it to take longer at the peak of summer or the depths of winter regardless. You’ll also likely use more battery capacity at those times for heating and cooling while you drive.

Smart Chargers and Scheduled Charging

Many of today’s Level 2 EV chargers can connect to your home’s Wi-Fi, allowing for smartphone app-based controls. They allow you to check charging status and set charging schedules to control power use. That can give you the control necessary to ensure your EV is always ready when you need it.

When a Faster Charger May Not Make a Big Difference

While it could be tempting to choose the fastest charger on the market, it’s not always worth the money. For one thing, your EV may not take advantage of the speed. For another, a faster charger could require more costly upgrades to your home’s electrical system. Generally, it’s best to buy a charger that’s just fast enough to meet your average needs with a little overhead for future-proofing. Reviewing these EV charger installation considerations can help you plan a system that fits your vehicle and home.

Why Professional Installation Matters

You’d also be wise to avoid the temptation to DIY a Level 2 charger installation. Only a professional electrician can ensure code compliance, balance panel loads, size the necessary breaker appropriately, and install proper wiring. They also know how to help you select the right installation location for your charger. Black-Haak can help you determine where to install your EV charger based on your parking setup and electrical system. If you do it yourself and make a mistake, you could damage your EV or risk the safety of your home and those inside it.

Signs Your Current Charging Setup Is Not Enough

If you already have an EV and a charger, it’s worth looking out for signs that you need a charger upgrade. For example, if you frequently feel range anxiety because you can’t charge fast enough at home, consider an upgrade. And if you’re using extension cords to power your charger or tripping breakers frequently, it’s time for an upgrade. Or, if you’re overly dependent on public chargers, a new home charger would be a good investment. Homeowners can also review Black-Haak’s frequently asked questions about EV charging for additional guidance.

Your Local EV Charging Experts

The bottom line is that your home EV charging experience depends on numerous factors. Everything from the charger itself to your EV’s battery capacity, your charger’s power circuit, and your driving habits affects it. To ensure you get a charger that meets your needs, consult an expert before choosing one. Black-Haak is your local EV charging expert, and we can help with that. Our electricians have the skills, training, and experience to ensure your charger installation goes smoothly.

If you’re interested in a home EV charger installation or upgrade in Greenville, WI, contact Black-Haak today.