Rate GD for medium‑power independent producers

Rate GD, which applies to medium‑power contracts, is an optional rate offered on backup power sold to independent producers whose main generating source is temporarily unavailable or under maintenance. The electricity purchased is used to replace the energy required for your essential loads and auxiliary services.

Rate GD does not apply if backup generators are the only equipment you use to generate electricity.

Independent producers may also be billed at the appropriate general rate, with the exception of Rate G9.

More information

This information has been simplified. For more details about Rate GD, consult Section 3 of Chapter 4 of the Electricity Rates [PDF 4.75 MB].


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).

Summer period

Period from April 1 through November 30, inclusive.

Winter period

Period from December 1 through March 31 of the next year, inclusive.


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).

Minimum billing demand (minimum demand)

The minimum amount of power that the customer must pay for each consumption period, regardless of electricity use. The threshold is set so that you pay your share of the costs Hydro-Québec incurs to meet your power needs at all times. The minimum billing demand is determined by the conditions of each rate, as indicated in the Electricity Rates.

  • For all rates except Rate L, the minimum billing demand is automatically determined based on the previous winter’s maximum power demand.
  • Rate L customers must set their own minimum billing demand, called “contract power,” based on the amount of electricity they expect to use.

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.

  • Low voltage: Voltage of 750 V or less.
  • Medium voltage: Voltage of more than 750 V, but less than 44 kV.
  • High voltage: Voltage of 44 kV or more.


Difference in electrical level between two points, expressed in volts (V).


Operation that involves increasing or decreasing voltage through a transformer.

Independent producer

A producer of electrical power who either consumes for its own needs or sells all or part of the electricity it produces to a third party or to Hydro-Québec.

Minimum charge (minimum monthly bill)

Minimum amount billable for electricity service even if little or no electricity has been used in the billing period.