3. Comparing Annual Heating Costs

The combination of heating load, energy source and heating equipment efficiency determines the annual cost of heating.

Calculating Heating Costs with Different Energy Sources

You may be interested in calculating the costs of heating with electricity and even comparing this amount to the costs of heating with other energy sources such as natural gas, propane, oil or wood. In this case, you can use the following procedure. First you need to find out the cost of the energy sources you wish to compare and the characteristics of the heating systems that you are considering.

Step 1: Determine the Price of Energy Sources in Your Area

Call your local electric utility, or gas or fuel suppliers to find out the cost of energy sources in your area. This should be the total cost of fuel delivered to your home, including any basic costs for which the supplier might bill you, as well as rental charges, as for, say, propane tanks. Be sure to get the prices for the energy sources in the same units used in Table 1. Write the costs in the spaces provided. If your natural gas price is given in gigajoules (GJ), you can convert it to cubic metres (m³) by multiplying the price per gigajoule by 0.0375. For example, $5.17/GJ x 0.0375 = $0.19/m³.

Table 1 Energy Content and Local Price of Various Energy Sources

Energy Soure	Energy Content		Local Unit Price
	Metric	Imperial

Electricity	3.6 MJ/kWh	3 413 Btu/kWh		$0._____ /kWh
Oil	38.2 MJ/litre	140 000 Btu/kWh		$0._____ /litre
Natural Gas	37.5 MJ/m³	1 007 Btu/ft³		$0._____m³
Propane	25.3 MJ/litre	92 700 Btu/gal (US)		$0._____litre
Hardwood*	30 600 MJ/cord	28 000 000 Btu/cord		_____$/cord
Softwood*	18 700 MJ/cord	17 000 000 Btu/cord		_____$/cord
Wood Pellets	19 800 MJ/cord	20 000 000 Btu/cord		_____$/cord

Conversion: 1000 MJ= 1 gigajoule (GJ) * The figure provided for wood are for a "full" cord, measuring 1.2m x 1.2m x 2.4m (4 ft. x 4 ft x 8ft.

Step 2: Select the Type(s) of Heating Appliance(s)

Choose the type of equipment you want to compare from the list of appliance types in Table 2 on page 36. Note the efficiency figures in the column titled "Seasonal Efficiency". By using these figures, you can calculate the savings you can achieve by upgrading your present system to a newer, more energy-efficient model, or by choosing a more efficient appliance that uses another energy source.

Table 2 Heating System Efficiencies and Energy Savings

Energy Source	Technology	Seasonal Efficiency (AFUE) %	Energy Savings % of Base**

Electricity	Electric baseboards	100
	Electric Furnace or boiler	100
	Air-source heat pump	*
	Earth-energy system (ground-source heat pump)	*

Oil	Cast-iron head burner (old furnace)	60	Base
	Flame-retention head replacement burner	70-80	14-23
	High-static replacement burner	74-82	19-27
	New standard model	78-86	23-30
	Mid-efficiency model	83-89	28-33
	Integrated space/ tap water system (mid-efficiency)	83-89	28-33 40-44

Natural Gas	Conventional	60	Base
	Vent damper with non-continuous pilot light	62-67	3-10
	Mid-efficiency model	78-84	23-28
	High-efficiency condensing furnace	89-97	33-38
	Integrated space/ tap water system (mid-efficiency)	89-96	33-38 44-48

Propane	Conventional model	62	Base
	Vent damper with non-continuous pilot light	64-69	3-10
	Mid-efficiency model	79-85	21-27
	Condensing model	87-94	29-34

Wood	Central furnace	45-55
	Conventional stove (properly located)	55-70
	"High-tech" stove (properly located)	70-80
	Advanced combustion fireplace	50-70
	Pellet stove	55-80

* Consult specialist ** Base represents the energy consumed by a standard furnace

Step 3: Select your House Type and Heating Load

From the list of cities and housing types in Table 3, select the combination that corresponds best to your area and house type. The heating load figures are expressed in metric units called gigajoules (GJ).

Table 3 Typical Annual Heating Loads in Gigajoules (GJ) for Various Housing Types in Canadian Cities

City	Old	New	New Semi-	Town-
	Detached	Detached	Detached	house

Victoria	85	60	45	30
Prince George	150	110	80	60
Calgary	120	90	65	50
Edmonton	130	95	70	55
Fort McMurray/	140	105	80	60
Prince Albert
Regina/	130	90	70	50
Saskatoon/
Winnipeg
Whitehorse	155	115	85	60
Yellowknife	195	145	110	80
Thunder Bay	130	95	70	55
Sudbury	120	90	65	50
Ottawa	110	75	55	40
Toronto	95	65	45	35
Windsor	80	55	40	30
Montréal	110	80	60	45
Québec City	115	85	65	50
Chicoutimi	125	90	70	55
Saint John	105	75	60	45
Edmundston	120	90	65	50
Charlottetown	110	80	60	45
Halifax	100	75	55	40
St. John's	120	85	60	45

Note: "New" means houses built after 1990, and "old" means houses built before 1990. Due to construction practices, and weatherizing and re-insulating (which can be different from house to house), these figures are only meant to be used as general guidelines; they should not substitute for an accurate heating requirement determination, as discussed in Chapter 5, page 41.

Assumptions:
Old detached - approximately 186 m²(2000 ft.²). New detached - approximately 186 m²(2000 ft.²). New semi-detached - approximately 139 m²(1500 ft.²). Townhouse - inside unit, approximately 93 m²(1000 ft.²).

Step 4: Use the formula

The annual heating cost is calculated as follows:

Energy Cost/Unit		Heating Load
______________	x	______________	x	100 000- = Heating Cost ($)
Energy Content		Seasonal Efficiency

Enter the cost per unit of energy and divide it by the energy content of the energy source; both numbers come from Table 1 on page 35.
Select the heating load for your type of housing and location from Table 3 on page 37; divide it by the seasonal efficiency of the proposed heating system from Table 2 on page 36.
Multiply the results of these two calculations, then multiply that result by 100 000.

The result should give you an approximate heating cost for your house. If you know your actual heating costs, as well as the type of heating system you have, you can modify the heating load originally taken from Table 3 to relief real load of your house.

Sample Calculation: You have an new detached home in Toronto and you would like to know what it would cost you annually to heat your dwelling with an electric force-air system with a seasonal efficiency of 100 per cent. Using the above equation, let us specify that electricity costs $0.0826/kWh, the heating load is 80 (Table 3) and the energy content is 3.6 (Table 1).

Annual cost of heating	$0.0826		80
with electricity	__________	x	_________	x	100 000	=	$1835.55
	3.6		100

If you would like to compare this heating cost to those of other types of heating systems or energy sources, replace the numbers in the formula with the appropriate ones for your comparison using Tables 1 and 2. If you have access to the internet, visit http://energuide.nrcan.gc.ca and check for the Heating Cost Calculator under Heating and Cooling Equipment.

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Source: Natural Resources Canada (NRCan) - Office of Energy Efficiency