Eligibility for Rate LG

Rate LG applies to an annual contract whose minimum billing demand is 5,000 kilowatts or more, unless the contract is principally related to an industrial activity.

This information has been simplified. For more details about Rate LG, consult Section 2 of Chapter 5 of the Electricity Rates [PDF 4.83 MB].

Structure of Rate LG

Billing for Rate LG includes the following:

  • An amount for the energy in kilowatthours (kWh) consumed during the period in question.
  • An amount for the billing demand in kilowatts (kW).

Rate LG is a monthly rate, which means the amount billed for power is based on a 30‑day period.

If applicable, the following may lower your bill:

Credit for supply at medium or high voltage

Hydro‑Québec’s rates assume that electricity will be supplied at low voltage. If you have equipment to step down the voltage of the electricity delivered to you or if you use electricity at medium voltage or high voltage, that means reduced costs for Hydro‑Québec. In return, you receive a monthly credit on your demand charge. The credit is determined according to the supply voltage.

Adjustment for transformation losses

Hydro‑Québec bills you only for the electricity you use. This means it absorbs the transformation losses associated with electricity delivery. If metering occurs before transformation, the electricity billed will include energy lost during transformation that does not reach the customer. So that you do not pay for energy losses, Hydro‑Québec grants an adjustment on the billing demand.

The following may also be billed in certain cases:

Charge for low power factor

Electrical equipment, whether yours or Hydro‑Québec’s, is designed to operate at a relatively stable voltage. Hydro‑Québec’s rate structure is designed in such a way as to encourage large‑power customers to maintain a power factor of at least 95% at all times.

When large‑power customers make less than optimal use of the electricity provided and have a power factor below 95%, Hydro‑Québec is forced to supply them with additional power and handle the impacts on the power system. The rate structure allows for Hydro‑Québec to bill this excess power to customers.

And when the maximum power demand is below 5,000 kW, customers must still maintain a power factor of 95% or more, or risk being billed at the price of power for excess kVA.

See Helping you understand your electricity rate

Rate LG prices in effect

Breakdown of billing

  • Price of energy 3.505¢/kWh
  • Price of power $13.432/kW

Applicable in certain cases

  • Credit for supply at medium or high voltage
    • Voltage of 5 kV to less than 15 kV $0.6169/kW
    • Voltage of 15 kV to less than 50 kV $0.9888/kW
    • Voltage of 50 kV to less than 80 kV $2.2075/kW
    • Voltage of 80 kV to less than 170 kV $2.7004/kW
    • Voltage of 170 kV or more $3.5683/kW
  • Adjustment for transformation losses 17.902¢/kW 

Rates in effect as of April 1, 2021. This table does not replace the Electricity Rates document in any way whatsoever.

Other rates or rate options

If you have a Rate LG contract, the following options may be of interest to you.

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 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).


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).

  • 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.

Power factor

Ratio of real power (in kW) and apparent power (in kVA). The power factor is expressed as a percentage and indicates the efficiency with which the customer uses the electricity provided. Hydro-Québec encourages its customers to maintain a power factor of at least 90% or 95%, depending on their rate.

Maximum power demand

Maximum power measured during a consumption period. It is the higher of the following two values: real power in kilowatts (kW), or a percentage (90% for domestic rates and small- and medium-power rates, or 95% for large-power rates) of the apparent power in kilovoltamperes (kVA).

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.

Winter period

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