Potential savings

By taking advantage of the equipment testing conditions, Rate L or LG customers can be temporarily exempted from certain conditions that apply to excess power demand.

Flexible terms and conditions

To benefit from these conditions, you must notify Hydro‑Québec in advance of the testing start date and duration. You’ll need to specify the nature of the new equipment, modifications or optimization work, as well as the power rating of the equipment to be tested.

The equipment testing conditions apply for a minimum of one hour and a maximum of one consumption period.

Calculation of billing amount

Rate L or LG, as the case may be, is applied to the billing demand recorded outside the test period(s), as well as to the energy for the consumption period in question.

In addition, for each 15-minute integration period of actual hours in the test period(s), an amount of per kilowatthour is applied to the excess of real power over the billing demand for periods with no testing.

More information

If you have any questions about this rate option, contact your commercial officer or designated agent. You can also reach our Business customer services by phone at 1 800 463‑9900 or by email at business@hydro.qc.ca.

This information has been simplified. For more details about the equipment testing conditions for large-power customers, consult Section 7 of Chapter 5 of the Electricity Rates [PDF 1.44 MB].

Power demand

Power a customer requires to meet energy needs at a given time. The higher the customer’s energy consumption at a given time, the higher the power demand.

Consumption period

Period during which electricity is delivered to the customer and which extends between the two dates used by Hydro-Québec for calculation of the bill.


Power used by electrical equipment over a given period of time. Expressed in kilowatthours (kWh), energy is calculated as power, expressed in kilowatts (kW), multiplied by the time during which the power is used, expressed in hours (h).

The formula for energy is as follows: energy (in kilowatthours) is equal to power (in kilowatts) multiplied by duration of use (in hours).

Real power

Amount of electricity consumed in a useful manner to operate equipment, such as a motor or a heating or lighting system. Real power is expressed in kilowatts (kW).


Electricity rate effective April 1, .


Total amount of electricity supplied at a given time. Expressed in kilowatts (kW), power is the combined effect of voltage, expressed in kilovolts (kV), and current, expressed in amperes (A).