1) What kind of energy savings can I expect from upgrading my old 70% efficient conventional furnace to a mid- or high- efficiency one?

You can use the following formula to determine the energy savings for upgrading to a more energy efficient furnace:

AFUE: Annual Fuel Utilization Efficiency

(AFUE of new furnace – AFUE of old furnace) / AFUE of new furnace = % energy savings

See the following table for examples:

*Take note, these percentage savings are strictly based on the “space-heating” portion of your monthly heating bill.

2) During the heating season, what is the ideal temperature to set my thermostat at during the night and when I am away?

It is recommended that settings of 20°C during the day and 17°C at night (or when nobody is at home) provide optimal comfort and efficiency.

As a rule of thumb, for every degree you consistently turn down your thermostat over an eight hour period, you will save 2 per cent (per degree) on the space-heating portion of your energy bill. A programmable thermostat will help you to regulate your daily and weekly settings and optimize your energy savings.

3) Is it true that if I turn down my thermostat, more energy is used to bring the temperature back up to the same level?

No, this is not the case. In fact, if you turn down your thermostat for more than a few hours you will save energy. Here’s why:

The energy “saved” during the time the temperature is dropping (ie. from 21ºC to 18ºC) offsets the “extra” energy used to bring the temperature back up (to 21ºC). Over the period where the temperature is continuously at the lowest setting (18ºC), this is considered saved energy on your heating bill.

4) We are leaving on vacation for a few weeks. What energy saving measures should I take before leaving?

• Setting your hot water tank to the vacation setting will ensure that water is heated only to a minimum level while you’re away. You may also choose to turn the pilot light off altogether, just remember to re-light it upon your return. Turning the pilot light of your hot water tank will result in a monthly savings of 0.37 Gigajoules (GJ).

For a video demonstration on re-lighting your pilot light, visit: 

http://www.atcogas.com/Safety/Safety_resources.asp  (2nd box down on the left in table)

If you do not feel comfortable re-lighting the pilot light yourself, please contact ATCO Gas at:

ATCO Gas Customer Assistance Centre
Monday to Friday from 7a.m. to 7 p.m. (closed on statutory holidays)
Calgary (403) 245-7888 Edmonton (780) 424-5222 Toll-free 310-5678

5) How do I determine the cost of operating an electrical appliance per month?

Though we pay for electrical use by kilowatt hours, the energy consumption of an electrical appliance is typically measured by watts. Determining the operating costs for an electrical appliance therefore requires converting the wattage of the appliance, to kilowatts (there are 1000 watts in 1 kilowatt). To find your monthly energy consumption for an electrical appliance, take the equipment wattage (W) and divide by one thousand, multiply by hours of use per day times days per month. This will give you an estimate of kilowatt-hours used per month.

W/1000*hrs/day*day/month=kWh/month

To find your monthly cost, take the energy consumption that applies (kWh) and multiply by your energy costs.

kWh/month*$/kWh=$/month

If no information is available on the specifications label for a product, an inexpensive Energy Meter that can calculate kilowatts can be purchased at a hardware store. Please follow proper operating instructions for these type of devices.

6) Why are my gas bills more than my neighbor’s when our houses are the same size?

Two neighbor’s comparing their gas bills is just as effective as comparing apples to oranges; it is not realistic or practical and often results in needless frustration.

The six variables listed below affect energy consumption in the home. Since the house is a system, it is critical that the variables are not viewed in isolation from one another but rather in relation to each other as a whole. Above all, some variables are easier to quantify than others; making the task of measuring a home’s overall energy efficiency tough and gaining a true comparison between two homes, even tougher.

a) Area of Heated Space

It is important to make the distinction between the area of heated space and the house area, as indicated in the house plans. The house area, generally measured in square feet, includes the entire house dimensions from the exterior. The area of heated space is significantly smaller than the house area due to the depth of the building envelope and internal wall assemblies.

b) Heating System Design and Size

The overall heating system design and size plays an imperative role in how effective heat is being delivered through the home. The following are examples when more energy is being burned than necessary:

• A poorly designed ductwork assembly, which does not properly distribute the heat throughout the home, forces the heating system to work harder to make up for the deficiencies.
   
• The furnace/boiler is greatly oversized (>15%) for the home’s heating requirements. This causes the system to operate at lower efficiency levels.  

c) Number of Gas Appliances

The greater the number of gas appliances in the home will contribute to an increase in gas consumption.

d) Energy Performance of Gas Appliances

How efficiently the appliance uses gas is determined by:

• its age and what technology was available at the time. I.e., a new furnace today is considerably more efficient than one from 30 years ago.
• its wear and tear. I.e., a conventional hot-water heater reduces in efficiency over time as residual sediment builds-up at the bottom of the tank.
• controls or devices used to improve the appliance’s energy efficiency. I.e., the replacement of a standard pilot with an ignition module for a hot water heater. 

e) Building Envelope

The building envelope refers to the home’s shell and plays a huge part in determining how effective the heating system operates. The tighter the building envelope, the better job it does in keeping valuable heat in and cool outdoor air out.
Both the air-leakage rate and thermal performance of the building envelope must be examined to measure its overall effectiveness in keeping the heat in.

Air-leakage rate: Air leaks may be present in a variety of locations in the building envelope. Typical air-leakage areas are: around windows and doors; electrical outlets exhaust fans and vents; light fixtures in the ceiling; interior trim and baseboards; cracks in the wall finish or ceiling; fireplace dampers; floor drains; and many more.
It is easy to locate air leaks on a cool windy day through the use of an incense stick, a feather or a thin piece of plastic. However, to measure the air-leakage rate, a depressurization (or, blower-door) test must be conducted by a heating contractor or certified energy advisor. This test determines the air change per hour in the home; the rate of which used indoor air is replaced with fresh outdoor air.

Thermal Performance: The building envelope is made-up of a variety of diverse materials; each having a unique impact on the overall effectiveness of the building envelope. These materials are what make up the home’s windows, doors, wall assembly, foundation and attic.
The thermal performance of the material is measured by R/in or by RSI/mm.

f) Occupancy Use and Lifestyles

Of all the variables listed, occupancy lifestyles is the most difficult to quantify. This is because consumption behaviors and patterns may be different for each household member and furthermore, may change from day to day. Some examples include:

• thermostat settings and setback
• length and frequency of showers and baths
• frequency of entrance doors opening and closing
• curtains open during the day and drawn in the evening to optimize heat gain
• the use of an electric space heater
• usage and type of light fixtures (light bulbs produce heat)
• frequency of guests (people produce heat)

7) What are the advantages of compact fluorescent light bulbs (CFLs) over regular incandescent ones?

• ENERGY STAR qualified bulbs use about 75 percent less energy than standard incandescent bulbs and last up to 10 times longer.
• Save about $30 or more in electricity costs over each bulb's lifetime.  
• Are available in different sizes and shapes to fit in almost any fixture, for indoor and outdoor use.
• Though CFLs are more costly to buy initially, the energy saved will quickly offset the extra purchase price when the bulb is being used for extended periods of time. 

ATCO EnergySense recommends proper disposal of CFL lightbulbs.  While the City of Edmonton offers a CFL disposal program to its residents, most municipalities do not yet offer this service.  In addition, most RONA, and Ikea locations across the province now offer CFL disposal.

8) I upgraded to a more efficient furnace last fall and see no difference in my heating bills. Why would this be?

First of all, when you compare heating bills make sure to isolate your energy consumption from the energy costs, as energy costs may fluctuate throughout the year.

Secondly, furnaces are tested and rated based on certain testing conditions.  However, there are factors that may influence the Annual Fuel Utilization Efficiency (AFUE) rating on the manufacturer's label of your furnace.

Here are some possible explanations that may cause your higher efficient furnace to consume more energy than expected: 

a) Colder outside temperatures requiring the upgraded furnace to operate more frequently.

By reviewing historical weather data and your consumption records, an ATCO EnergySense energy analyst can perform a degree day analysis. This compares the amount of energy used to the actual temperatures that occured during that heating period. 

b) The new furnace is too big for your home’s heating requirements.

A greatly oversized (> than 15%) furnace will not perform at peak efficiency therefore will reduce the rated AFUE.

ATCO EnergySense recommends that prior to purchasing a new furnace, a  comprehensive heat-loss analysis is performed by a certified heating contractor.  The heat-loss analysis not only takes into account the area and age of the house but also window count, size, and efficiency as well as insulation depths in the attic, external walls and basement.

c) Change of lifestyle. 

For example: change of number of occupants, amount of times refridgerator or external doors are opened and closed. 

9) Is it more cost effective to heat my home with a furnace or fireplace?

A furnace is designed to heat the home's total heating area, therefore it is the most efficient method available.  A fireplace is designed to heat smaller areas within your home, therefore when occupying an area by your fireplace, turn your furnace thermostat down to save some energy. 

10) I have noticed on very cold days the furnace seems to run constantly. Does this mean I need a larger furnace?

No.  A properly sized furnace will operate at peak efficiencies and on a continuous basis on very cold days.

11) Why am I being asked to make my home airtight and then mechanically ventilate it?

Many homeowners question the logic behind tightening a house and then ventilating it.  It’s important to understand the relationship between ventilation, indoor air quality, the integrity of the building envelope and energy efficiency.

Controlled mechanical ventilation is the key to an energy efficient, healthy home.  When the ventilation is controlled, you will be able to more effectively regulate the humidity level in your home and control when you want fresh air brought in and stale air removed from the home.  This will save you on your heating dollars and remove any possible condensation problems occurring within the building envelope, as can happen with uncontrolled air leakage.  In turn, the homeowner is able to better manage indoor air quality and enjoy a more comfortable home.

Installing mechanical ventilation is common in newer houses because they are generally built more airtight than older houses.  In addition, new construction materials can contain a high level of moisture and pollutants that are emitted into the interior living space. 

No.  In fact, the installation of add-on insulation to residential water heaters is not acceptable under the Safety Codes Act in Alberta.  Water heaters that are certified to the applicable CSA Standards must meet the requirements for energy efficiency; the field installation of an add-on insulation kit would be unnecessary.