Types, differences, examples, and how to choose one.
A home EV charger does exactly what the name says: it charges your EV (electric vehicle) at your home. In fact, it is called EVSE (electric vehicle supply equipment) by tech geeks, but most people just refer to an electric car charger. Every person that owns a BEV (battery electric vehicle) or PHEV (plug-in hybrid electric vehicle) would need to be able to charge their vehicle at home, because residential charging is extremely convenient and still the cheapest way to charge your car if you live in the USA, especially if you take advantage of the lower electricity rates that may be available at certain hours in many states. In fact, the US Office of Energy Efficiency & Renewable Energy says that EV owners do more than 80 percent of their vehicle charging at home, where this refers to a single-family home while the vehicle is parked in the safety of the garage, plugged into an electric-vehicle charger. Of course, the job of the charger is to transfer the electrons from the electrical outlet to your EV's battery and the rate at which this happens is often expressed in miles of range per hour. Different types of EV chargers charge at different rates and may require certain equipment to be installed or purchased.
The best home charging station for your EV would be the one that can recharge your battery to full charge in the fasted time. If you own a PHEV with a relatively small battery, you might not need a powerful charger, as the battery's charge could be replenished at night while you sleep. A simple Level 1 charger will probably be the best EV charger for your needs in this scenario. However, anything bigger, and full EVs, require a more powerful home EV charger, which would be the slightly more complicated Level 2 setup that can still be installed at home and is a lot faster. However, be sure to consult a trusted electrical contractor before any work is done on your house's electrical system and get more than one cost estimate for the work to be done. Furthermore, the manufacturer of your EV will be able to give you accurate information as to exactly what charging equipment you would need to charge your car. Do not hand over your hard-earned money until you have collected all the information and can make an informed decision.
If you don't live in a private home but in a multi-unit complex, there might already be EV charging stations on site. Many of these complexes now provide EV-charging stations to attract tenants and do their bit for sustainability. You can even work with the owner of your building to have charging stations installed, but just be sure to follow the correct legal channels.
Level 1 EVSE provides the simplest, least powerful, and, consequently the slowest way to charge your EV at home. It means you are simply plugging into the standard 120 V AC (alternating current) plug and this will recharge the typical EV battery at a rate of around three to five miles of range per hour, depending on the vehicle. This is perfectly adequate to top up the battery of a PHEV or an EV with a small battery overnight. You need no special equipment on Level 1, besides a dedicated branch circuit. The cord used needs no more than the standard three-prong plug that goes from the car charger to the wall outlet, with a standard J1772 connector to plug on the other end that goes into the vehicle's charging port.
A Level 2 home EV charging station can also be installed, but for this, you need a dedicated circuit of 20-100 amps, which will allow you to charge through a 240 V plug. This should not be a problem in the vast majority of cases, because most homes already have an adequate 240 V supply for higher-power appliances. If your home doesn't have adequate supply, rather expensive upgrades to the electrical system will be required, and you will have to jump through several regulatory and legislative hoops - but a professional electrical contractor should know these. Many Level 2 chargers come with an app, so you can monitor the charging process from a smartphone, too. Level 2 is a lot faster and adds anything from around 20 miles to a maximum of 60 miles of range to your EV's battery per hour. This EVSE is more expensive than Level 1 equipment and, depending on the type and brand, the price of such a charger can be as high as $2,000. For reference, a Tesla home charger costs $500. Keep in mind that this price does not include labor for installation and neither does it take into account any tax credits or utility or state incentives that may apply for installing an EV charger at your home. You can check on the US Department of Energy's website whether you qualify for any incentives, as well as check out more useful information in our article about EV charging stations.
It sounds like the perfect solution, having your EV charge up in the garage while you sleep. But is it all good news?
Level 1 chargers get a bit of flak for being the slow and cheap option, but the truth is that you might need no more than that if you just run a PHEV and an overnight charge on your Level 1 charger is sufficient to top it up. You stand to save quite a bit in terms of equipment and installation costs too. In such cases, a Level 1 charger is simply the best choice. However, if you have a larger EV battery to top up, or time is of the essence, you always have other options and you can buy a Level 2 charger. It will cost more initially, but you get a much faster charging rate and you can fully charge even quite large EV batteries overnight. If you are considering a multi-unit complex, best to look out now for the ones offering charging on-site, as many of them in the US now do.
A normal Level 1 charger is simply a cord with two ends. One end has the three-pronged plug that plugs into the wall outlet and the other has the plug that fits into your car's charging port. A Level 2 charger usually comes in the form of a wallbox that has to be installed by a professional electrical contractor. A Level 2 portable electric car charger has the charging unit incorporated in the cord and you must still plug it in manually. It will depend on the type you have. You don't have to buy it from the vehicle manufacturer if it doesn't come standard, as many third-party, universal car chargers are available. An EV charger from Home Depot, regardless of brand, can do the job too. Just be sure that you buy a well-rated brand to ensure its reliability. Lastly, there are split wall boxes available for two cars, if you have to charge them simultaneously.
Simply plug it into the wall or wall socket and off you go. Some cars/chargers even have smartphone apps, so you can schedule charging for off-peak times, charge to a predetermined level, and keep track of charging. To preserve maximum battery life, the typical EV battery should not be charged much over 80 percent full on a daily basis. Consult your manufacturer or read your car's manual to see how to best treat your EV's battery. Ideally, it should not be run down completely either, if this can be avoided.
How long is a piece of string? There is no firm answer and it depends on the power your charger puts out, the size of the EV's battery, and how much charge was still left in it before you started. At an optimistic rate of five miles of range per hour, a standard 120 V Level 1 charge will take more than two days to completely charge the flat 100-kWh battery of a Tesla Model S Performance. A Hummer EV's 200-kWh battery would take twice as long! With a 240 V Level 2 charger, eight hours should be more than enough for the job. The smaller the battery and the stronger the charge, the shorter the time. Also, keep in mind that the maximum charging rate is not maintained when a battery exceeds 80 percent and slows markedly to prevent overcharging. But how fast does it really have to be? Fast charging is expensive and if you consider, for example, how long it takes to charge a car battery at 50 amps - in the case of a Toyota Prius Prime, not much more than an hour - you have to ask yourself if you really need a 50-ampere home EV charger installation.
The maximum rate at which one can charge electric cars' batteries will depend on the car and will be limited by the car's charging software to the maximum allowable value. You will have to check what your car can accept. As an example, a Chevrolet Bolt can accept a maximum of 50 kW, while a Porsche Taycan can accept a maximum charge of 270 kW. It is probably safe to say that most EVs won't reach the limit of their charging speed using a home electric vehicle charger of any kind.