Planning Your EV Charger Installation

A structured approach to assessing demand, electrical capacity, site layout, and permitting for electric vehicle charging projects.

Assessing Demand for EV Charging

The first and most critical step in planning an electric vehicle (EV) charging installation is understanding the expected demand for charging at your property.

Demand assessment is particularly important for properties serving employees, residents, or guests, where charging needs may vary widely based on usage patterns and dwell time.

How to evaluate charging demand

A common and effective approach is to distribute a survey to potential users, such as employees, residents, or frequent visitors. The goal is to estimate both current and future charging needs.

• How many current EV drivers will need charging?
• How many users plan to purchase an EV in the next 1–3 years?
• How long vehicles are typically parked at the site?
• Whether users need fast turnaround charging or overnight charging

Understanding how many users will charge simultaneously—and for how long—helps determine both the number of chargers and the appropriate charger type.

Assessing Electrical Capacity for EV Charging

Once potential demand is understood, the next step is evaluating whether the property’s existing electrical system can support the planned EV charging load.

This assessment should be completed with facilities staff, maintenance personnel, or a licensed electrician who is familiar with the property’s electrical infrastructure.

Key electrical system information to gather

• Locations of existing electrical panels across the property
• Distance between panels and proposed parking or charging locations
• Panel voltage ratings (120/208V, 120/240V, or 480V)
• Approximate existing electrical loads
• Estimated available spare capacity on each panel
• Available physical space for additional equipment such as subpanels, disconnects, or transformers

With this information, it becomes possible to determine whether there is sufficient excess capacity to support the planned EV charging demand.

When Existing Electrical Capacity Is Insufficient

If the property does not have adequate spare electrical capacity, there are two primary options:

Upgrading existing electrical service

Upgrading the main electrical service or switchgear may be appropriate as part of a broader building renovation or infrastructure upgrade.

• Requires coordination with the utility and local permitting authority
• May involve temporary power interruptions
• Can trigger additional code compliance upgrades

While effective, this option can be costly and time-consuming.

Establishing a new electrical service supply

An alternative approach is adding a new electrical service dedicated to EV charging.

Although electrical codes generally prefer a single service connection, exceptions exist under National Electrical Code (NEC) provisions for specific use cases.

• Allows EV charging loads to be isolated from the building’s main service
• Can simplify billing by placing EV chargers on a separate utility meter
• May allow selection of a utility rate optimized for EV charging

Selecting Where to Locate EV Charging Equipment

Choosing the right physical location for EV chargers can greatly impact both installation cost and user satisfaction.

Best practices for charger placement

• Minimize distance between chargers and power sources to reduce wiring costs
• Locate chargers near destinations where users spend the most time
• Favor surface-mounted conduit or landscaped routing over concrete or asphalt cutting
• Plan locations that allow future charger expansion

Accessibility Requirements for EV Charging

When EV chargers are available to the public, accessibility requirements must be considered. In the United States, these requirements are governed by the Americans with Disabilities Act (ADA).

In California and some other jurisdictions, additional building code provisions define specific requirements for EV-accessible and van-accessible charging spaces.

• At least one accessible EV parking space is typically required for public charging
• Accessible spaces require larger dimensions and access aisles
• Providing accessible EV spaces may reduce the total number of standard parking spaces

Permits and Inspections for EV Charger Installation

Most jurisdictions treat EV charger installations as standard electrical work. Permits are often approved quickly when applications are complete and accurate.

Common causes of permitting delays

• Incomplete permit applications
• Installations that do not follow electrical code requirements
• Failure to follow manufacturer installation specifications

EV chargers are classified as continuous electrical loads, similar to HVAC or electric drying equipment. Inspections are focused primarily on safety and code compliance.

Working with qualified contractors and ensuring proper design documentation can significantly reduce permitting and inspection delays.

Final takeaway: Successful EV charger installations begin with careful planning—accurate demand assessment, realistic capacity evaluation, thoughtful site selection, and early coordination with utilities and permitting authorities.