How the Ontario ULO Rate Plan Can Lower Your Hydro Bill With a Home Battery

Understanding Ontario's ULO Electricity Rate Plan

Ontario offers residential electricity customers three pricing plans: Time-of-Use (TOU), Tiered, and Ultra-Low Overnight (ULO). The ULO plan suits homes that can shift their consumption to overnight hours, such as homes with an electric vehicle or a battery storage system.

Here are the ULO rates set by the Ontario Energy Board (OEB), in effect November 1, 2026:

Source: Ontario Energy Board, Regulated Price Plan prices in effect November 1, 2026.

How a Battery Uses the ULO Rate Gap

On the ULO plan, a battery can charge overnight at 3.7¢/kWh and power your home during the 37.7¢/kWh weekday peak from 4 to 9 PM. Every kilowatt-hour the battery supplies at peak is one you don't buy from the grid at the highest price.

How much that saves depends on how much electricity you use at peak, your rate plan and the size of the system. Some energy is also lost when a battery charges and discharges, and the on-peak price applies only on weekdays. An installer can estimate the savings for your home from your hydro bills.

Why ULO Is Especially Valuable in Muskoka & Simcoe County

Hydro bills in rural Muskoka and Simcoe County tend to be higher than urban Ontario for several reasons: electric heating is more common in areas without natural gas infrastructure, older housing stock is often less energy-efficient, and long winters mean high heating loads.

Homes like these often use a lot of electricity during the weekday peak, which is the energy a battery on ULO can shift to overnight. A home in Huntsville or Bracebridge with electric baseboard heating, for example, may have a large peak-hour load in winter.

On ULO, weekends and holidays are charged at 9.1¢/kWh from 7 AM to 11 PM and 3.7¢/kWh overnight. The 9.1¢ rate is the same as the Time-of-Use off-peak rate.

How to Switch to the ULO Rate Plan

ULO is offered through Ontario's local distribution companies (LDCs) — the utility named on your hydro bill. In much of Muskoka District and rural Simcoe County that is Hydro One.

To switch, contact your utility and ask for the ULO rate plan. They will confirm whether your home is eligible.

You can switch to ULO without a battery, but you'd pay the 37.7¢ on-peak rate for anything you use from 4 to 9 PM on weekdays. ULO works best for homes that can move most of their use to overnight hours, which a battery makes easier.

Adding Solar to the Equation

When you add solar panels to a battery system on ULO, your savings stack in two ways:

1. Solar charges your battery during the day — storing energy you generated yourself
2. Your battery discharges at peak (4–9 PM) — using stored solar energy instead of 37.7¢/kWh grid power

Solar panels produce the most in the long, sunny days of late spring and summer. On a good day, a well-sized system can charge the battery and run the home's daytime loads at the same time. How much solar adds depends on the size of the array, your roof and your usage, so ask the installer for an estimate for your home.

Is the ULO Plan Right for Your Home?

ULO is an excellent fit if:

• You have or are installing a home battery system
• You can shift most of your major electricity loads (dishwasher, laundry, EV charging) to overnight hours
• You have electric heating or cooling that can be pre-conditioned overnight

ULO is less ideal if you have high daytime electricity needs that cannot be shifted — for example, if you work from home and run high-powered equipment during the weekday 4–9 PM window without a battery to offset it.