Rate DT – Dual Energy
How a dual-energy system eligible for Rate DT works
For a dual-energy heating system to be eligible for Rate DT, it must automatically switch from one energy source to the other when it receives a signal from the outdoor temperature sensor, usually built into Hydro-Québec’s meter.
1. Higher-price indicator light
An indicator light installed in your house, preferably in plain view, will help you manage your use of electricity better. It shows you which type of energy is being used for heating and, as a result, which price applies.
When the light is off, the heating system is running on electricity and you will be billed at the lower price. When the light is on, the heating system is running on fuel, because the outdoor temperature is below −12°C or −15°C, depending on the region. Electricity use will therefore be billed at the higher price.
Note: Installation of the indicator light is optional. Dual-energy heating systems work with or without an indicator light.
2. Dual-energy meter
The dual-energy system requires a special meter that records electricity consumption at the two different prices.
There are two lights on the meter housing:
- The green light indicates that the switch is working. It should always be on.
- The red light indicates that the outdoor temperature is below the critical threshold of −12°C or −15°C, which means electricity will be billed at the higher price.
Electrical installations of 200 A and 400 A or more are eligible, but those of 320 A are not.
3. Temperature sensor
The outdoor sensor sends a signal to the heating system when the temperature drops below –12°C or –15°C (depending on your climate zone).
4. Mode selection switch
All dual-energy systems that are eligible for Rate DT are equipped with an automatic switch permitting transfer from one source of energy to the other. However, some dual-energy systems have a manual switch that can be used to choose whether your heating system runs on fuel, dual energy or electricity.
To take advantage of Rate DT, you need to set the mode selection switch to dual energy. Depending on the outdoor temperature, the system automatically switches from electricity to fuel or vice versa, whichever is more economical.
5. Most commonly used heating systems that qualify for Rate DT
- Dual-energy forced-air systems of the following types:
- Dual-energy forced-air system (furnace)*, a fuel-burning system with built-in electric heating elements
- Fuel-burning forced-air system (furnace)* combined with a central heat pump
- Fuel-burning forced-air system (furnace)* combined with electric heating elements
- Dual-energy hot-water systems (with radiators, for example), combining a fuel-burning boiler and an electric boiler
*Note: Forced-air systems are often called furnaces.
Maximize your savings by using the right source of energy
To maximize your savings under Rate DT, it is important that you use the right source of energy at the right time, based on the outdoor temperature and the price billed.
When do you use electricity and when do you use fuel?
It all depends on the oudoor temperature:
Temperature
Above or equal to –12°C or –15°C (depending on the region)
Indicator light in your home
Off
Price of electricity
Lower price: /kWh
Recommended source of energy
Heat using electricity
Temperature
Lower than –12°C or –15°C
(depending on the region)
Indicator light in your home
On
Price of electricity
Higher price: /kWh
Recommended source of energy
Heat using fuel
In addition to choosing the right energy source for your heating needs, based on the outdoor temperature and price billed, it is also important to make the best possible use of your dual-energy system and to use electricity efficiently.
If your dual-energy system is equipped with a manual switch to go from one energy source to the other (fuel or electricity), we recommend that you select the dual-energy mode at all times. That way, your system will automatically use the most economical energy source based on the outdoor temperature.
Given that all the electricity consumed during cold weather is billed at the higher price under Rate DT, it’s a good idea to use less hot water and limit your use of nonessential appliances and electronics during those periods. You’ll save more than 80% on electricity consumption that is put off until it isn’t as cold out.
Your savings under Rate DT are not as high as you expected?
Analyze your situation to identify ways that can help you start saving again with Rate DT.
Have you made changes to your heating system?
In the following situations, Rate DT is not right for you anymore:
- You’ve totally removed your dual-energy system.
- You’ve made major changes to your dual-energy system, so it no longer meets the conditions for Rate DT.
If either of those statements is true, please get in touch with our customer services department right away to change your rate.
You haven’t made any changes to your dual-energy system?
If your setup has not changed, the following reasons may explain why you haven’t enjoyed any savings:
-
The fuel part of your dual-energy system broke down last winter and you didn’t have it repaired right away or you ran out of fuel over the course of the winter.
Since you’re supposed to heat with fuel in cold weather, you should make sure that the fuel part of your dual-energy system is working properly. If it burns oil or propane, keep the tank topped up. We therefore suggest having the fuel part of your dual-energy system repaired immediately whenever it breaks down and having your tank filled before winter comes. That way you can heat with fuel during cold snaps and reduce your electricity use during the periods when it is billed at the higher price.
-
The switch on your dual-energy system was in electric or manual mode all winter.
For the biggest savings, set the switch to dual-energy or automatic mode. This will ensure the following:
- Fuel is used for heating as soon as the outdoor temperature dips below –12°C or –15°C, depending on the region
- Electricity is used as soon as the temperature is above or equal to –12°C or –15°C, depending on the region
You should only use manual mode briefly while waiting for repairs to be done.
-
You used an electric space heater when it was very cold out.
For the biggest savings, use as little electricity as possible whenever the outdoor temperature is below –12°C or –15°C, depending on the region. You should avoid using an electric space heater. It’s also a good idea to use less hot water and limit your use of nonessential appliances and electronics. You’ll save more than 80% on electricity consumption that is put off until it isn’t as cold out.
-
The winter was particularly harsh.
Your savings at Rate DT depend on the weather. You save less during a very cold winter, because a lot of your electricity use is billed at the higher price. But you save more in a mild winter, because almost all your electricity use is billed at the lower price.
So it’s important to look at your savings over several years to see whether Rate DT is still the best rate for you.
Usage and maintenance
Manual mode selection switch
All dual-energy systems eligible for Rate DT are equipped with an automatic switch permitting transfer from one source of energy to the other. However, some dual-energy systems have a manual switch that can be used to manually select the energy source. This manual switch is completely optional. Many dual-energy systems without a manual switch have a central heat pump as the electric component.
To maximize your savings under Rate DT, be sure the switch is set to dual-energy mode so that your dual-energy system switches between energy sources automatically.
Hydro-Québec does not recommend manual switching. It should only be used if one of the components (electric or fuel) of the dual-energy system stops working properly. If this happens, you can use manual mode to continue heating with the component that is still functioning.
If you decide to switch your heating system’s energy source manually, we advise you to switch to fuel mode as soon as the temperature goes below –12°C or –15°C (depending on the region). At those temperatures, heating with fuel is less expensive given that electricity is billed at the higher price.
Replacing the dual-energy indicator light
To obtain a free indicator light, please call 1 800 363‑7443.
Note: It should be noted that dual-energy heating systems work with or without an indicator light. Its only purpose is to indicate which energy source is being used for heating and therefore which electricity price applies.
Procedure
- Replace the light at a time when the lower price under Rate DT applies. Make sure the red light to the left of the control on the meter box is OFF.
- Lift off the cap above the indicator light and remove the screw it was hiding.
- Disconnect the two wires behind the indicator light.
- Remove the mounting plate of the old indicator light if it has one.
Important
The new light is built into the box. Do not try to remove it. Install the entire box.
- Open the indicator light box by pressing on both sides.
- Secure the box to the wall using the screws provided.
- Connect the two wires to the terminal block (order of connection is insignificant).
- Close the box.
- Check that the new indicator is working properly once the higher Rate DT price applies (red light on the meter box is ON).
Replacing your dual-energy heating system
Are you wondering if the savings under Rate DT are enough to offset the price of replacing your dual-energy system?
Yes, generally speaking, savings at Rate DT over a period of 20 years will cover all the extra costs of replacing your entire dual-energy system, compared with buying an electric system. The extra costs can also be absorbed more quickly if you realize additional savings related to summer uses of electricity (air-conditioning, pool heater).
Furthermore, you are more likely to allocate the cost of replacing the main parts of your dual-energy system over several years as part of regular maintenance, rather than replacing the entire system at once.
Have you decided to replace your dual-energy system with another type of heating system?
If so, your contract is no longer eligible for Rate DT. It’s important that you contact us without delay so we can switch you to another rate.
Features of a dual-energy system eligible for Rate DT
What types of auxiliary fuel are eligible?
- Natural gas
- Oil
- Propane
- Wood pellets
What are the most commonly used heating systems that qualify for Rate DT?
- Dual-energy forced-air systems such as:
- Dual-energy forced-air system (furnace)*, a fuel-burning system with built-in electric heating elements
- Fuel-burning forced-air system (furnace)* combined with a central heat pump
- Fuel-burning forced-air system (furnace)* combined with electric heating elements
- Dual-energy hot-water systems (with radiators, for example), combining a fuel-burning boiler and an electric boiler
*Note: Forced-air systems are often called furnaces.
What are the eligibility criteria for Rate DT?
- The contract is eligible for Rate D, DP or DM.
- The dual-energy system used meets specifications.
- The dual-energy meter is installed. The meter registers separately the electricity used when the lower and higher prices under Rate DT apply.
- For agricultural customers, other conditions must be met for Rate DT to apply.
What criteria must a dual-energy system meet if a homeowner wishes to qualify for Rate DT?
- Your dual-energy system has to use electricity as the main source of energy and a fuel as an auxiliary source.
- The capacity of the dual-energy system in fuel mode must be sufficient to heat your home. The two energy sources of the dual-energy system cannot be used simultaneously.
- Your dual-energy system must be equipped with an automatic switch permitting transfer from one source of energy to the other based on the outdoor temperature.
- It must have a temperature sensor supplied and installed by Hydro-Québec connected to the switch. The sensor indicates when the system must switch from one source of energy to the other in response to the outdoor temperature.
Which Rate DT eligibility criteria apply to farms?
When a distribution service loop serves a farm or both a farm and a dwelling, Rate DT applies if the following conditions are met:
- This distribution service loop must supply at least one dual-energy system.
- Each dual-energy system has to use electricity as the main source of energy and a fuel as an auxiliary source.
- The capacity of each dual-energy system in fuel mode must be sufficient to heat the premises it serves. The two energy sources of the dual-energy system must not be used simultaneously.
- The installed capacity of each dual-energy system must be no less than 50% of the installed capacity of the premises it serves.
- Each dual-energy system must be equipped with an automatic switch permitting transfer from one source of energy to the other.
- Each dual-energy system must have a temperature sensor supplied and installed by Hydro-Québec connected to the switch. The sensor indicates when the system must switch from one source of energy to the other in response to the outdoor temperature.
- The installed capacity of all premises supplied by this distribution service loop that are not served by a dual-energy system must not exceed 10 kilowatts.
See the eligibility criteria regarding domestic rates for farms [PDF 693 kB]
How can I check if I am eligible for Rate DT?
Is an apartment building, community residence or rooming house that uses a dual-energy system eligible for Rate DT?
Please contact our customer services department at 514 385-7252 in the Montréal region or at 1 888 385-7252 elsewhere in Québec for more information about the features of dual-energy systems that qualify for Rate DT.
More information
To find out more about Rate DT, consult Section 5 of Chapter 2 of the Electricity Rates [PDF 1.44 MB].
During most of the year
When the temperature is above or equal to −12°C or −15°C, depending on the region.
During a cold spell
When the temperature goes below −12°C or −15°C, depending on the region.
First tier
Your energy consumption is divided into two tiers. The first tier (1st tier), which is set at 40 kWh per day, or 1,200 kWh per month, is billed at a lower price than the second tier (2nd tier).
Rate
Electricity rate effective April 1, .
Oil
Estimated cost of oil: /litre.
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Electricity – Rate D
Consumption billed at the first‑tier price of Rate D at April 1, , for consumption associated with central air‑conditioning, and the second‑tier energy price of Rate D for pool heating.
Dual-energy – Rate DT
Consumption billed at lowest Rate DT price, as at April 1, .
Distribution service loop
Any portion of a power line, not located along a public highway, extending the Hydro-Québec system to the connection point.
See the eligibility criteria regarding domestic rates for farms[PDF 693 Kb]
System access charge
A set amount, expressed in dollars per month or cents per day depending on the applicable rate, that the customer must pay for the electricity service.
Beginning April 1, 2019, the term fixed charge was replaced with system access charge.
Multiplier
A factor that is applied to the system access charge, to the consumption at the various energy price tiers and to the base billing demand, as applicable depending on the rate.
Energy
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).
Energy (kWh) = power (kW) x time used (h).
Power
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).
Winter period
Period from December 1 through March 31 of the next year, inclusive.
Summer period
Period from April 1 through November 30, inclusive.
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).
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.
Electricity as the main source
The dual-energy system in electrical mode uses an electric forced-air system, an electric boiler, a traditional central heat pump or a geothermal heat pump.
Fuel as the auxiliary source
“Fuel as the auxiliary source” refers to a fuel such as natural gas, oil, propane or wood pellets that is used as a second source of energy to heat your home.
Dual-energy system in fuel mode
The dual-energy system in fuel mode must be able to keep your home warm during cold spells without the electrical mode being used at the same time.
Automatic switch
A dual-energy heating system eligible for Rate DT automatically switches from one energy source to the other when it receives a signal from the outdoor-temperature sensor: electricity when the temperature is above or equal to –12°C or –15°C, depending on the region; fuel when the temperature goes below that critical threshold.
Off-grid systems
“Off-grid system” refers to a system that is not connected to Hydro‑Québec’s main grid. In this particular case, it refers to the systems in Îles-de-la-Madeleine, Clova, Obedjiwan or Île-d’Anticosti or one of the Nunavik systems. Rate DT (dual energy) is not available to homes and farms located in those regions.
Electricity as the main source of energy
The dual-energy system in electrical mode uses an electric forced-air system, an electric boiler, a traditional central heat pump or a geothermal heat pump.
Fuel as the auxiliary source
“Fuel as the auxiliary source” refers to a fuel such as natural gas, oil, propane or wood pellets that is used as a second source of energy for your farm’s heating needs.
Dual-energy system in fuel mode
The dual-energy system in fuel mode must be able to keep the farm premises it serves warm without the electrical mode being used at the same time.
Comments:
- The installed capacity of each dual-energy system must be no less than 50% of the installed capacity of the premises it serves.
- The installed capacity of all premises that are not served by a dual-energy system must not exceed 10 kilowatts.
Off-grid systems
“Off-grid system” refers to a system that is not connected to Hydro‑Québec’s main grid. In this particular case, it refers to the systems in Îles-de-la-Madeleine, Clova, Obedjiwan or Île-d’Anticosti or one of the Nunavik systems. Rate DT (dual energy) is not available to homes and farms located in those regions.