Time-of-Use Electricity Pricing: How to Shift Loads and Save Money

Under time-of-use (TOU) electricity pricing, the same kilowatt-hour costs nearly twice as much at 4 PM as it does at 2 AM. For a Canadian commercial facility consuming 100,000 kWh monthly, shifting just 20% of consumption from on-peak to off-peak hours can save $1,500–$3,000 per year—without reducing total energy use by a single kilowatt-hour.

TOU pricing is designed to align consumption with grid capacity: higher rates during peak demand periods encourage businesses to shift flexible loads to off-peak hours when generation is cheaper and more abundant. The challenge is identifying which loads in your operation can actually move—and by how much. This guide explains how TOU pricing works across Canada, where the biggest load-shifting opportunities lie, and how to calculate and verify your savings potential.

How Time-of-Use Pricing Works

Time-of-use electricity rates charge different prices per kilowatt-hour depending on when energy is consumed. Utilities define periods—on-peak, mid-peak, and off-peak—based on typical grid demand patterns. The goal is to send a price signal that encourages consumption when the grid has surplus capacity and discourages it when the grid is strained.

Standard TOU structures include three periods:

• On-peak — Highest demand hours, typically weekday late afternoon and early evening (e.g., 4–9 PM in Ontario winter). Highest rate.
• Mid-peak — Moderate demand hours, typically weekday daytime outside on-peak windows. Middle rate.
• Off-peak — Lowest demand hours, typically evenings, overnight, and all hours on weekends and statutory holidays. Lowest rate.

TOU pricing is distinct from demand charges (which penalize peak kW regardless of timing) and tiered pricing (which charges different rates based on total monthly consumption volume, not timing). Many commercial accounts pay TOU energy rates plus demand charges—making load shifting valuable for reducing both cost components simultaneously.

Current TOU Rates in Ontario and Other Provinces

Ontario has the most developed TOU framework for commercial customers under the Regulated Price Plan. As of November 2025, OEB-set TOU rates are:

• Off-peak: 10.2 ¢/kWh (weekends and holidays: all hours; weekdays: 7 PM–7 AM)
• Mid-peak: 14.4 ¢/kWh (weekdays: 11 AM–5 PM in winter; 7 AM–11 AM and 5 PM–7 PM in summer)
• On-peak: 20.2 ¢/kWh (weekdays: 7 AM–11 AM and 5 PM–7 PM in winter; 11 AM–5 PM in summer)

Ontario also offers ultra-low overnight (ULO) pricing with a deeply discounted overnight rate of approximately 2.8 ¢/kWh from 11 PM to 7 AM daily, trading higher weekday on-peak rates for overnight savings. See our complete guide on Ontario electricity rates: TOU, tiered, and ultra-low overnight for plan comparison and selection criteria.

Other provinces with TOU or time-differentiated pricing include:

• BC Hydro — Optional TOU rates for large general service accounts (above 35 kW demand), with on-peak rates approximately 40% higher than off-peak
• Alberta — Competitive retailers offer TOU-style products; regulated rate option varies seasonally
• Quebec — Hydro-Québec's Rate Flex D offers dynamic pricing with critical peak events for commercial customers

Ontario TOU on-peak rates are approximately double off-peak rates—a facility shifting 25,000 kWh monthly from on-peak to off-peak saves roughly $250 per month in energy charges alone.

Calculating Your Load-Shifting Opportunity

Before changing operations, quantify the opportunity using your actual interval consumption data.

1. Obtain 12 months of interval data — Download from your utility portal or energy management platform. Fifteen-minute or hourly intervals are ideal.
2. Categorize consumption by TOU period — Apply your rate schedule's period definitions to each interval. Calculate total kWh in on-peak, mid-peak, and off-peak buckets.
3. Identify shiftable loads — Review on-peak and mid-peak consumption for equipment and processes that could operate during off-peak hours without business impact.
4. Estimate shiftable kWh — For each shiftable load, calculate how many kWh could move to off-peak. Be conservative—account for operational constraints.
5. Calculate savings — Multiply shiftable kWh by the rate differential (on-peak rate minus off-peak rate). Add demand charge savings if shifting reduces peak kW.

Example: A food processing facility uses 120,000 kWh monthly—40,000 on-peak, 35,000 mid-peak, 45,000 off-peak. Shifting 15,000 kWh of batch processing from on-peak to off-peak saves 15,000 × ($0.202 − $0.102) = $1,500/month ($18,000/year).

Load Shifting Opportunity 1: Manufacturing and Production Scheduling

Manufacturing facilities often have the largest load-shifting potential because production equipment draws significant power and batch processes can be scheduled flexibly.

Shiftable manufacturing loads include:

• Batch mixing and processing — Chemical, food, and pharmaceutical batch processes that don't require continuous daytime operation
• Curing, drying, and baking cycles — Thermal processes with flexible start times
• CNC machining and fabrication — Long-run jobs scheduled overnight when labour and energy rates are lower
• Water heating and boiler pre-heat — Thermal storage filled during off-peak for daytime process use
• Compressed air system fill cycles — Large storage receivers filled overnight at off-peak rates

A 500 kW production line running 6 hours daily on-peak costs approximately $600/day in energy at Ontario TOU rates. Shifting that same run to off-peak saves $300/day—$78,000 annually on a single production line. For broader industrial strategies, see our industrial energy management guide.

Load Shifting Opportunity 2: HVAC Pre-Conditioning

HVAC is typically the largest electricity consumer in commercial buildings—and pre-conditioning is one of the most effective load-shifting strategies because thermal mass stores energy.

Pre-conditioning works by:

• Pre-cooling — Running chillers overnight or early morning (off-peak) to lower building temperature before occupants arrive. The building's thermal mass maintains comfort through on-peak hours with reduced chiller operation.
• Pre-heating — Warming the building during off-peak overnight hours, then allowing temperature drift during on-peak periods with minimal supplementary heat.
• Ice storage — Making ice overnight and using it for daytime cooling—effectively storing off-peak electricity as thermal energy.

A 200-ton chiller running 4 hours on-peak daily consumes approximately 800 kWh at on-peak rates ($161/day). Pre-cooling during off-peak and limiting on-peak chiller operation to 1 hour reduces on-peak HVAC energy by 600 kWh daily, saving $60/day ($15,600/year). For detailed HVAC strategies, see our guide on HVAC energy optimization for commercial buildings.

Load Shifting Opportunity 3: Commercial Dishwashing and Laundry

Restaurants, hotels, hospitals, and institutional kitchens operate dishwashers and laundry equipment that consume significant electricity and hot water. These loads are highly shiftable because cleaning cycles don't need to coincide with meal service or guest occupancy.

Best practices for hospitality and food service:

• Run dishwashers after 11 PM — Post-service cleanup can shift to overnight off-peak or ULO hours
• Batch laundry overnight — Hotels and hospitals running 2–3 laundry cycles overnight instead of during on-peak daytime hours
• Timer controls on water heaters — Heat water storage tanks during off-peak for daytime use
• Weekend batch processing — Deep cleaning and heavy laundry on off-peak weekend hours

A hotel with three commercial laundry machines (each 15 kW) running 6 hours daily on-peak consumes 270 kWh at on-peak rates ($54/day). Shifting to off-peak saves $27/day ($9,855/year). See our hotel energy management guide and restaurant energy efficiency guide for sector-specific strategies.

Load Shifting Opportunity 4: EV Fleet and Forklift Charging

Electric vehicle adoption is accelerating across Canadian commercial fleets—and unmanaged charging can set costly demand peaks while consuming expensive on-peak energy. Smart charging transforms EV loads into off-peak assets.

EV and forklift charging strategies:

• Off-peak scheduling — Program all chargers to begin at 11 PM (off-peak or ULO start) and complete before morning operations
• Staggered charging — Sequence charger activation to prevent simultaneous demand spikes (critical for demand charge management—see our peak demand charges guide)
• Smart charging controllers — Systems that dynamically adjust charging rate based on facility demand, TOU period, and state of charge
• Opportunity charging discipline — Avoid midday top-up charging during on-peak hours unless operationally critical

A warehouse with 20 electric forklifts (each requiring 15 kWh nightly) consumes 300 kWh per charging cycle. At Ontario on-peak rates, charging during the day costs $61/cycle; off-peak costs $31/cycle—a savings of $30/night ($10,950/year).

Load Shifting Opportunity 5: Batch Processes, Water Heating, and Refrigeration

Beyond the major categories above, numerous commercial loads offer shifting potential:

• Water heating — Commercial water heaters and boilers can heat storage tanks overnight for daytime draw. A 50 kW water heater running 4 hours off-peak instead of on-peak saves $20/day.
• Refrigeration defrost cycles — Program defrost to occur during off-peak hours rather than on demand during peak periods. Defrost cycles draw 2–3× normal compressor power.
• Ice making — Commercial ice machines running overnight fill storage bins for daytime use in restaurants, hotels, and fisheries.
• Pool and spa heating — Recreational facilities heating water during off-peak and maintaining temperature with reduced on-peak input.
• Data backup and batch computing — Schedule non-urgent server workloads and data processing during off-peak hours.

Building Automation: Automating Load Shifts

Manual load shifting works for initial savings, but automation ensures consistency and captures opportunities that depend on precise timing relative to TOU period boundaries.

Automation tools for TOU load management:

• BAS TOU schedules — Program building automation to change HVAC, lighting, and auxiliary setpoints at TOU period transitions
• Smart relays and contactors — Hardware interlocks that prevent specific equipment from operating during on-peak periods
• Energy management system (EMS) integration — Centralized platforms that orchestrate load shifts across multiple systems based on rate schedules
• Timer-based controls — Simple, low-cost timers on dishwashers, water heaters, and charging stations for facilities without full BAS

Automation eliminates reliance on staff remembering to shift loads and ensures savings persist through staff turnover and schedule changes. Integration with HVAC optimization and demand limiting creates compound savings across energy rates and demand charges.

Monitoring TOU Performance and Cost Simulation

Implementing load shifts is only half the equation—you must verify they are working. Interval data analysis shows whether consumption is actually moving to off-peak periods or whether operational realities are preventing planned shifts.

Key monitoring metrics:

• On-peak kWh as percentage of total — Track monthly; target reduction of 5–10 percentage points per quarter
• Load factor improvement — Ratio of average demand to peak demand; higher load factor indicates better load flattening
• Cost per kWh by period — Verify you're paying expected rates and quantify actual savings vs. baseline
• Shift verification by equipment — Submeter data confirming specific loads moved as scheduled

Energy Wiz's Intelligence Hub provides cost simulation tools that model load shift scenarios against flat, tiered, and TOU rate structures—quantifying savings before operational changes and tracking performance after. Combined with smart alerts that flag on-peak consumption anomalies, teams verify load shifting delivers expected returns. Learn more in our real-time energy monitoring guide.

Load Category Comparison Table

Conclusion

Time-of-use electricity pricing turns your consumption schedule into a direct cost lever. Canadian businesses on TOU rates who analyze their interval data, identify shiftable loads, and implement scheduling changes—manually or through automation—typically save 8–15% on energy charges without reducing total consumption.

Start with the highest-impact, lowest-complexity opportunities: HVAC pre-conditioning, overnight charging, and batch process rescheduling. Verify shifts with interval data monitoring, and use cost simulation to model additional scenarios before investing in automation infrastructure.

Model TOU savings, monitor load shift performance, and set alerts with Energy Wiz—Canada's mobile energy management platform with forecasting and simulation for flat, tiered, and TOU rate structures.