System access charge

The system access charge, expressed in dollars per month, based on the applicable rate, is a set amount to be paid for the electricity service itself.

It is prorated to the number of days in the consumption period if it is not 30 days. As a result, this amount will vary slightly from one bill to the next, depending on how many days are in the consumption period.

As regards business rates, only Rate G has a system access charge. However, for rates M and G9, the billed amount cannot be less than the applicable minimum charge.


Energy, expressed in kilowatthours (kWh), is billed at a general rate for all customers, with no exceptions. In some cases, a first tier of kWh 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 G9 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 G9, the percentage is 75%.

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

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

Minimum charge

Rate G, M and G9 contracts also include a minimum charge. Customers pay the minimum charge when they consume little or no electricity during a billing period. This charge is set so that you pay your share of the costs Hydro‑Québec incurs to meet your power needs.

System access charge

A set amount, expressed in dollars per month or cents per day depending on the rate, to be paid monthly the electricity service itself.

The expression “fixed charge” has been replaced by “system access charge” as of April, 2019.


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).

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 domestic rates and 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 kilowatts (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 produces magnetic fields and which is not useful power for the customer.

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.

Winter period

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

Contract power

Minimum 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.

Minimum charge (minimum monthly bill)

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

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.

Monthly periods

Period of 30 days, which may begin on any day of the month, established by Hydro‑Québec for billing purposes.