Fixed charge

The fixed charge is the amount paid for each billing period, even if you consume little or no energy.

Fixed charges are calculated based on an amount established on a 30-day basis, multiplied by the number of days in the consumption period. This amount will vary slightly from one bill to the next, depending on how many days are in the consumption period.

Rates M, G-9, LG and L have no fixed charges. However, for rates M and G-9, the billed amount cannot be less than the applicable minimum billing demand.


Energy, expressed in kilowatthours (kWh), is billed at a general rate for all customers, with no exceptions. In some cases, a first tier of kilowatthours will be billed at one amount, and any energy used beyond this threshold will be billed at a lesser amount.


Customers don’t generally use electricity at exactly the same intensity throughout a given period; as such, their power demand (in kilowatts) will constantly vary. Hydro-Québec must be equipped to respond at any time to the maximum power demand of its customers’ facilities.

Even though the power demand is often less than the maximum power demand, billing for electricity consumption is insufficient to cover Hydro-Québec’s equipment operations and maintenance costs. This is why Hydro-Québec bills customers who use a great deal of electricity for power demand.

Generally speaking, billing demand is calculated as described below.

Billing demand calculation for small- and medium-power rates

Billing demand for rates G, M and G-9 corresponds to the greater of the following two values:

For rates G and M, the minimum billing demand is set at 65% of the maximum power demand during a consumption period that falls wholly in the winter period included in the 12 consecutive monthly periods ending at the end of the consumption period in question. For Rate G-9, the percentage is 75%.

For Rate G, the demand charge only applies to consumption over 50 kW.

Billing demand calculation for large-power rates

The billing demand for rates L and LG will be the greater of the following two values:

For Rate LG, the minimum billing demand is set at 75% of the maximum power demand during a consumption period that falls wholly in the winter period included in the 12 consecutive monthly periods ending at the end of the consumption period in question. This must not, however, be less than 5,000 kW.

For Rate L, the minimum billing demand corresponds to contract power.

Fixed charge

A set amount to be paid monthly for electricity service, even if there is little or no energy consumption.


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).

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.

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 small- and medium power rates, or 95% for large power rates) of the apparent power in kilovoltamperes (kVA).


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).

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 (kW).

Apparent power

Amount of electricity that Hydro-Québec supplies to a customer, expressed in kilovoltamperes (kVA). When it is used, apparent power breaks down into real power (kW), which runs devices, and reactive power (kVAR), which creates magnetic fields and which is not useful power for the customer.

Minimum billing demand

The minimum amount of power that the customer must pay for each consumption period, regardless of its electricity use. It applies to all business customer accounts.

  • 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.

Winter period

The period from December 1 of one year through March 31 of the following year, inclusive.

Contract power

Minimum billing demand that a large-power industrial rate customer (Rate L) agrees to pay and that Hydro-Québec must be ready to supply at any time in response to the customer’s demand.