How does Optiwatt decide when to start a charge?

Optiwatt’s EV charging platform is designed to put your needs first. Our goal is to ensure a seamless charging experience that maximizes savings, minimizes emissions, and guarantees that you’re never left stranded without charge. In this article we'll explain how Optiwatt’s charging prioritization works when utility partners request to limit charging, or in the event of emergencies.

Charging Priority Waterfall: Determining When to Charge

Our “Priority Waterfall” sequence is structured from the vehicle’s perspective: "Should I be charging right now?" This hierarchy ensures your needs are met first, followed by environmental considerations, and finally, utility-driven events. The below charging rules are listed beginning with the highest priority first, and then cascading down in decreasing priority.

1) User Override

• Condition: When you plug in your car, the Start Charging button will appear in the app. Please note that this may take up to 20 minutes depending on your model of vehicle. When you click Start Charging, charging starts immediately.
• Purpose: Overrides all other schedules or events.

2) Never Stranded Limit

• Condition: If your battery is below the minimum State of Charge (the measurement of how much energy is left in a battery, also know as SoC), charging will start. The default threshold is set to 20%, but if you want to change that, you can do so in the Settings tab of your vehicle's Devices page.
• Purpose: Ensures a minimum battery level to prevent you from being stranded.

3) Grid Emergency Event

• Condition: If an emergency event is scheduled by the utility, charging will stop.
• Purpose: Temporarily suspends charging to support grid stability during emergencies.

4) Scheduling: Trips

• Condition: If you’ve set up a Trip to exceed your standard SoC, we will charge your vehicle to that percentage by the time you indicate.
• Purpose: If you're embarking on a longer trip that requires a higher SoC than normal, we'll help you hit your desired percentage.

5) Scheduling: Ready By

• Condition: If you’ve set a scheduled departure time and target SoC, charging will start accordingly.
• Purpose: Ensures your vehicle reaches the desired SoC by your departure time, prioritizing early charging if needed.

6) Scheduling: Start Time

• Condition: When you set a regular charging schedule, charging will start within your designated time.
• Purpose: Lets you define a static window in which to start charging.

7) Grid Standard Event

• Condition: During scheduled standard grid events, charging will pause.
• Purpose: Temporarily adjusts charging based on utility grid needs.

8) Daily Optimization (Save Money/Save the Planet Modes)

• Condition: If charging isn’t optimal for your selected mode (e.g., Save Money, Save the Planet), charging will pause.
• Purpose: Optimizes for the lowest-cost or least carbon-intensive time to charge.

Charging Plans Overview:

Save Money - Charges during your utility plan’s lowest-cost hours. (Note: benefits apply only to variable-rate plans.)

Save the Planet - Charges during low carbon-emission periods on the grid based on your region.

Save Money + Save the Planet - Combines both optimizations, prioritizing cost savings first, then emissions.

9) Plugged-In State

• Condition: If your vehicle is plugged in and battery
• Purpose: Ensures immediate charging when no other managed conditions are in place.