How does EV charging work?

Some EV charging stations can be installed simply by plugging them into a standard wall outlet while others require an electrician’s installation.  The time it takes to charge your vehicle will also vary based on the kind of charger you use.

Charging Levels:

Level 1 chargers use a 120 volt AC plug and typically deliver 2-5 miles of range per hour of charging.  These chargers are most commonly used at home since they are the least expensive option, but they also take the longest time to charge your vehicle’s battery.  As such, most people typically use these types of chargers overnight.

Level 2 chargers can be used in both residential and commercial applications and are commonly installed with solar arrays.  They use a 240 (residential) to 208 (commercial) volt plug and cannot be plugged into a standard wall outlet.  Instead, they are installed by a licensed electrician.  Additionally, they may require a service upgrade, especially in older homes or buildings.  These chargers deliver 10-60 miles of range per hour of charging and can fully charge a vehicle’s battery in as little as 2 hours.

Level 3 chargers can offer 60-100 miles of range with only 20 minutes of charging!  These are typically used only in commercial and industrial applications since they require specialized equipment to install and maintain.  They also generally require 480 volt service.

Can I use Solar To Power My EV Charger?:

Simply put, yes.  Instead of exporting any solar electricity you don’t use to the grid you can use the electricity to charge your EV instead.  This process is very similar to how excess energy is stored in a battery connected to a solar PV system.

Keep in mind however, when you charge your EV from your solar really depends on how effective the process will be.  In other words, if you charge your EV during the day your solar PV system can easily help, or in some cases, fully charge your EV (depending on solar array size and the other appliances in your home that are drawing from your solar array.)  Alternatively, if you’re like most people you do the majority of your driving during the day and and plan on plugging your electric vehicle into the charging station in the evening.  In that case, your solar PV system may not do much in the way of helping charge your EV.

Perhaps, this means you set the majority of your appliances (things like the pool filter, etc) to run during the day so you can draw from the solar energy you are generating, then only draw from the grid at night to charge your EV and supplement your nighttime household energy consumption.  And/or, you also install a battery to store the excess energy you’ve created during the day and use this to charge your home at night while drawing from the grid only to charge your EV.

In the latter scenario, it’s worth looking into whether your electricity company will allow you to use energy from the grid for free.  Hypothetical Example:  Let’s say your electric company allows you to push up to 500 kWh to the grid, but you charge your EV at night (from the grid) and consume nearly that much so it’s a “break even” in terms of excess energy pushed to the grid vs. energy you’ve consumed by charging your EV.  In those instances, they may not even charge you to charge your EV.

All these points are definitely items to consider when considering EV, especially when you are planning to install solar; you’ll want to size your solar array to accommodate your future electric vehicle charging needs.

Important Notes:

If you are considering adding an EV charging station to your home or business, you’ll first want to get with your utility provider whether that’s Oncor or someone else.  They will require you to complete a Load Requirement form where you’ll enter your current load vs. your requested load.  From there, they will investigate whether or not your home will require a service upgrade to accommodate EV charging.  There may or may not be a fee for this; it’s best to inquire with the utility to be sure.
Any electrical work required to install EV charging stations most often involves engineered drawings to be submitted to your municipality for plan review since a permit and subsequent inspection will be required.

See Also:

Should I install a EV charging station when I get my solar installed?
Can I retrofit an EV charging station?
Can I add an EV charging station to my home or business even if I don’t yet own an electric vehicle?
Where can I find a list of EV charging stations in the DFW area?
North Texas Electric Auto Association