Do I need an electrical service upgrade?

Installation

Do I need an electrical service upgrade?

October 10, 2022

avatar
Nick Sherry
Electrical Lead

TL;DR

In most cases, you won't need an electrical service upgrade for EV charger installation. However, your home does need to have sufficient electrical service capacity and breaker space to safely install an EV charger. Most homes have an electrical service of between 100 to 200 amps.This is the maximum electrical current that your utility can send to your home. We’ll produce a electrical load calculation based on your home’s square footage and existing appliances to determine if a Level 2 charger can be safely installed.

What should I do if I have insufficient breaker space?

If your home has insufficient breaker space to install an EV charger, we’ll help you determine if it’s best to:

  1. Remove fastened electrical appliances that are not in use (e.g. spa, pool equipment, etc.)
  2. Reconfigure the existing breakers in your electrical panel to create the required space (e.g. by installing tandem breakers)
  3. Install a sub-panel, which provides space for future appliances, but is the most expensive solution

What should I do if I have insufficient electrical capacity?

If your home has insufficient electrical capacity to install an EV charger, we’ll help you determine if an electrical service upgrade is necessary. While expensive, some homeowners select this option so they have capacity to add more electrical appliances (e.g. electric water heater, heat pump HVAC systems, induction stove, etc.) in the future. If you only plan to install an EV charger, the following options may help you avoid a service upgrade:

  1. Remove fastened electrical appliances that are not in use (e.g. spa, pool equipment, etc.)
  2. Configure your EV charger to draw lower amperage (e.g. 32A instead of 40A)
  3. Use a circuit splitter such as a NeoCharge
  4. Install an energy management solution like the Tesla Neurio Energy Meter, Emporia Vue 3, Wallbox Power Meter, or DCC-12

If your home has some excess electrical capacity, but not enough to install an EV charger at the maximum amperage it can draw, you may be able to configure your EV charger to draw a lower, safe maximum amperage e.g. 32A instead of 40A. This can be done via hardware on some chargers like the Grizzl-E Classic. The major tradeoff of setting a lower amperage is slower charging speed.

The NeoCharge Smart Splitter is a good solution for homes that have existing 240V outlet that can be shared between an existing appliance (e.g. a dryer) and an EV charger. Read our NeoCharge Smart Splitter guide to decide if this is a good solution for you.

If you don’t have an existing 240V outlet that can be shared, the next option would be to explore if an energy management solution can be installed in your existing electrical panel. These solutions require current transformers (CTs) to be installed, which can be done on most top-fed or bottom-fed electrical panels. However, they CANNOT be installed on most center-fed electrical panels.

For Tesla Wall Connectors, the most affordable solution is a Tesla Neurio Energy Monitor. This solution dynamically balances load between your EV and your home to charge at the maximum safe speed. While many appliances are turned on, the system slows EV charging. When appliances are turned off, power is redirected to your EV. Wallbox offers the Wallbox Power Meter, a similar solution for Wallbox Pulsar Plus EV Chargers, while an Emporia Vue 3 can be used with Emporia EV chargers.

If you’d like to use an alternative EV charger, the best energy management solution is the DCC. It’s a bit more expensive to install, but more flexible and works with any charger. The DCC monitors overall power consumption of your home and temporarily deactivates EV charging when load exceeds a safe threshold (~80%).

Navigating all of these options can be complex, so Treehouse has developed software to assist you with this process.

Ready to try Treehouse for yourself?

Get a free estimate

Related articles

thumbnail
Installation

How to Prepare for Your EV Charger Installation

December 1, 2023

We've put together a few helpful resources to prepare you for installation day.

avatar
Nick Sherry
thumbnail
Installation

What is GFCI Protection?

May 1, 2023

Installing more than one GFCI on the same circuit can result in nuisance tripping. For this reason, we recommend installing a hardwired charger.

avatar
Nick Sherry
thumbnail
Installation

Federal Pacific Electric and Zinsco Panels

August 28, 2022

Federal Pacific Electric (FPE) and Zinsco panels have design flaws that can cause their breakers to fail, creating a safety hazard.

avatar
Nick Sherry
Copyright 2022 Treehouse
License CSLB #1093949