EV Chargers can use a ton of power to charge your electric vehicle at home. Given that each electrical service (panel) will have restrictions as to how much power it can supply at any given time, many customers may find themselves in a tricky spot requiring them to either reduce their available charge rate or adding a significant (and costly) electrical service upgrade in order to use an EV Charger at home.

No worries though! The PowerSmart upgrade for our EV Chargers allows you to install an Energy Management System (such as the Vue 2 or Vue 3 Energy Monitor) to track the usage of your available electrical service, and then provide automated controls for the EV Chargers' charge rate to keep your power supply under the specified thresholds. An effective and 100% safe way to provide the convenience and safety of at-home charging without the expensive service upgrade that would've been required.

The US National Electric Code (NFPA 70, 625.42(B) and 750.30) provides the requirements involved to have a system like this to work, and the Emporia Vue 3 (or Vue 2) Home Energy Monitor and Emporia Energy Level 2 EV Charger both qualify for this functionality.

Imagine this: You have 150A service provided to you from the utility provider (with a matching 150A main breaker in the panel). The sum total of your consumption in the household can reach 120A, thus only allowing up to 30A of charging for your EV Charger at any given time in the existing electrical panel. Since your vehicle can charge up to 48A, you'd be losing that extra 18A of charge rate (and charging slower than what would be available) if wanting to "fit" the EV Charger capacity in the existing panel. With PowerSmart, you can setup a Vue 3 (or Vue 2) to track your mains and watch your total system usage. With that enabled, you can set your max charge rate to 48A on the EV Charger, and that charge rate will be available anytime your household usage from the rest of the system is < 100A or so. If your household consumption starts increasing (and thus would bring you over the 150A service rating) - then we'll turn the EV Chargers' charge rate down as needed to prevent your service capacity from overloading your system. Once you have more capacity available (as detected by the Vue 3 or Vue 2 Energy Monitor), then we'll be able to increase the charge rate again as high as possible given the limitations available in the system.

This functionality provides you the safety required to ensure your electrical service is within appropriate limits all while granting you the automated control to enable the most effective Level 2 EV charging experience possible.

PowerSmart was designed to manage the available charge rate based upon your total system load. Here are some similar but distinct situations where the PowerSmart feature will not work correctly:
1.) Multiple EV Chargers on a shared circuit - given that PowerSmart is operated based on the 200A CT measurements tracking your system mains, multiple EV Chargers on a shared electrical circuit will not be able to operate independently of each other with this feature.

2.) "Load Shedding" based on circuit measurements other than system mains - per UL Certification requirements, the PowerSmart feature is exclusively limited to monitoring your system mains and adjusting amperage based on that total. Itemizing this functionality to specific branch circuits instead of mains may be an opportunity in the future but is limited to system mains at the moment.

This knowledge base is pretty new for the Emporia team. Our goal is to provide all of the information we can to help you manage your energy in better ways. If this article wasn't helpful, or we could be more clarifying on any points please reach out to the Customer Support team and we'll certainly work to improve these guides.