Straight Talk Articles

What Really Works? 7 Energy-Savings Myths
April, 2019

Dear Pat: When it comes to saving energy, it can be confusing to figure out what works and what doesn’t. I know you usually just answer one question, but can you let me know what you think about a few things I’ve heard over the years? – Keeley


Dear Keeley: Sure. Fire Away!


Q: Is it true turning lights off and on uses more energy than just leaving them on?

A: No. Turning off lights reduces energy use. Turn off LED and incandescent bulbs every time you leave the room.  The situation is a little different with compact fluorescent bulbs. Turning them off does save energy, but can shorten the life of the bulb. The rule of thumb is to turn them off any time they won’t be used for 15 minutes or more(1).


Q: Would replacing my old windows with new, more efficient ones really cut my energy use in half?

A: No. While replacing inefficient windows with new, efficient windows can cut the heat loss through the windows in half or more, the windows probably account for only about 25-30% of your space heating cost (2). The amount of  energy you use for heating and cooling is likely one third to one half of your total energy use, so replacing your old windows might only reduce your total energy bill by about 10%. When you consider the high cost of new windows, you may not recoup your investment for 15 or 20 years, or even longer.


Q: Burning wood in my fireplace should save money. Right?

A: Possibly, but a lot of conditions need to be met. The wood needs to be dry and available at low cost and it needs to be burned efficiently in a properly-installed, properly-placed high-efficiency wood stove or fireplace insert (3). Otherwise, it’s likely you’ll lose as much heat up your chimney as you’re distributing throughout the house.


Q: My kids claim using the dishwasher is just as good as washing by hand. Are they right?

A: Yes – in fact, it’s usually better! Dishwashers, properly used, actually use less water while doing a better job, and as a bonus, they will save you over 200 hours a year (4).  For maximum savings, make sure your water heater is set to about 120 degrees(5)  and use the most energy-efficient wash dry settings.


Q: It’s sometimes better to heat individual rooms with an electrical space heater and keep the doors closed to trap the heat, isn’t it?

A: It’s possible to save money with an electric space heater if you use it only a few hours a day and reduce the temperature two or three degrees in the rest of the house.  Space heaters can cause fires (6) so they need to be used wisely and never left unattended (7).    Which brings us to your next question…


Q: It’s smart to close the vents in rooms that aren’t being used, right?

A: Most experts advise against this because closing supply registers forces your furnace or AC unit to work harder. They advise keeping all your vents and doors open (8).  If your forced air system supplies too much heat to some rooms and too little to other rooms you should talk to a heating and air conditioning professional about modifying your ductwork.


Q: Does the age of my home determine its efficiency?

A: Newer homes tend to be more efficient because energy codes have improved, but every home can have hidden energy issues, no matter its age

This column was co-written by Pat Keegan and Brad Thiessen of Collaborative Efficiency. For more information on energy efficiency myths, please visit the April 2019 more information page.



(1) Source:

(2) Source:

 (3) Source:

(4)  Source:

(5)  Source:

(6) Source:

(7) Source:

(8) Source:


pellet stove.jpg

A properly-installed pellet stove can be an energy-efficient winter heating option. Source: US Dept of Agriculture.