Is Your Home Ready for an Electric Vehicle?
If you are considering purchasing an EV, you are probably excited that you will be able to charge it at home while you sleep, rather than at a gas station! EVs have unique power requirements, so it is important to consider your home’s ability to charge your new vehicle. In many cases, upgrades may be required, but are usually fairly inexpensive. In some cases EV manufacturers or dealerships may even include charging equipment installation in the sale price of the vehicle. Upgrades will require a licensed electrician.
In situations where electrical panels are outdated, undersized, or far from the location you want to install your charging equipment, expensive upgrades may be required.
What You Need to Know
There are 2 typical home charging options:
Level 1
120 Volt (V) (standard wall outlet): This may work for light EV use, but if you have a lengthy commute, it will not supply energy fast enough to replenish your battery for the next day’s drive. Depending on your battery size and required range, charging might take 9 to 24 hours.
Level 2
240V (like an electric dryer outlet): Level 2 EVSE equipment comes in a variety of different sizes and will charge batteries at different rates. Most combinations of car and charging equipment will deliver a charge in 4 to 6 hours.
Important!
EVs have different charge acceptance rates. This means some charge faster than others – but they also draw more power, which can be more than your home’s electric panel and electrical service from your utility is designed to handle. Improper planning can result in expensive electrical upgrades that can be avoided in many cases!
How to Avoid Unnecessary Costs
There are a few things you can do to make sure you are planning a successful EVSE installation.
- Find out what your vehicle’s maximum charging acceptance rate is. This is measured in kilowatts (kW) and/or AMPS and will define your maximum energy requirements. If your vehicle has a low acceptance rate, you might want to consider installing a slightly larger circuit for future expansion. Be sure to check with the utility to ensure your service can support your proposed load.
- Ask the utility how much load your service can handle.
- Determine what your electrical panel can accommodate.
- Make sure your licensed electrician is aware of all relevant codes and permit requirements.
- If you are planning to purchase a second EV in the future, it might be worth while to have some of the upgrades done at the same time to avoid additional labor and permit fees in the future.
New Construction
If you’re a home builder, consider wiring your new homes for 240V EV charging. This will make your homes more attractive to today’s buyers and will save them money down the road. Many jurisdictions are requiring EV-readiness in local building codes, thus it is best to begin planning now.
The International Code Council’s new codes state “New construction shall facilitate future installation and use of Electric Vehicle Supply Equipment (EVSE) in accordance with the National Electrical Code (NFPA 70).” These codes apply to single-family homes and multi-family residences.
What You Need to Know
Sizing: New homes should be wired for level 2 (240V) charging. This entails installing at minimum, a dedicated 240V/40A circuit.
Interior Installations: For interior garage installations, consider locating the outlet in a location that will be easy to access, and won’t require excessive EVSE cord length. Consider installing the charging station in a location that will allow the main walkway in the garage to remain free of cords.
See local codes for installation height requirements (NEC 625.30 B) and protective measures to avoid physical damage (NEC 110.27).
Exterior Installations: Exterior EVSE will generally be installed on a wall or a pedestal. Be sure the equipment is rated for exterior installations. Consider placing the equipment in a location that will be easy to access and will require excessive EVSE cord length. Consider installing the charging station in a location that will allow the main walkway to remain free of cords.
See local codes for installation height requirements (NEC 625.29) and protective measures to avoid physical damage (NEC 110.27).
Multi-Family Installations: Multi-family applications may require extensive planning to ensure your build meets code and provides an appropriate structure for metering/billing and connection with dwellings/units.