"Efficiency myths, busted!" first appeared on iafrica.com on 18 January 2010. It was the 11th most read "Financial fitness" article of 2010. Liked it? Get your finances in shape in 2011 - bookmark http://personalfinance.iafrica.com/.
There was a time, not too long ago, that South Africans could brag about having the cheapest electricity in the world. Those days are well and truly over and more of us are struggling to find ways to rein in soaring energy costs.
It's great that so many people are trying to curb their consumption, but how do you know that your action plan is the correct one? After all, many strategies people pursue are based on beliefs that are entirely false. Some of those widely held beliefs are merely myth even though they seem extremely plausible and gain wide acceptance. It is, however, time for them to be busted.
It takes more energy to turn a light back on, especially a fluorescent one, than to simply leave it on. Not! It's time to bring the truth to, uh, light...
It takes more electricity to turn a light back on than to leave it on.
This myth suggests that you should rather keep the light burning if you're only going to leave the room for a short while. There is, however, no power surge when you turn on a light so turning it off always saves electricity even if it's only for a moment.
Compact fluorescent lamps (those curly energy saving bulbs) are expensive.
Compact fluorescent lamps (CFLs) cost more than the old, energy wasting ones that has been around since the 1880s. Thing is, they last 10 times longer and use up to 80 percent less electricity, making them cheaper than the old, incandescent type. In fact, a 100 watt equivalent CFL will pay for itself in a few months if you use it for two or so hours each day.
CFLs are dangerous as they contain loads of mercury. Considering the danger they pose, the small amount of energy they save isn't worth the risk.
Firstly, the amount of electricity they save is not small and you'll achieve massive savings if you replace all your light bulbs with CFLs.
Secondly, there is absolutely no risk as long as the bulb doesn't break. But what about mercury that gets into the environment? Well, power plants put out more mercury to power a CFL than is contained within it. Furthermore, mercury produced at the plant is released into the atmosphere where, in contrast to mercury contained in CFLs, it cannot be recycled.
How much mercury does a CFL contain? No more than five milligram for a standard CFL while low-mercury CFLs hold as little as one milligram. To put that figure into perspective consider that a thermometer or dental filling contains about 500 milligrams of mercury while almost 14 milligrams get emitted at a power plant to power an incandescent light bulb.
So, if you're worried about mercury in the environment you've got even more reason to switch to CFLs for lighting.
The CFL mercury scare is nonsense and hard to understand seeing as though tube like fluorescent lights with much larger amounts of mercury have been widely used for decades without any problems.
Changing a light bulb won't make any difference to the environment.
False! False! False! The energy saved by installing 100 000 CFLs could power every streetlight in Britain for a year and each CFL will end up saving 38 kilograms of carbon dioxide emissions.
Changing all your light bulbs will save you money and make the world a cleaner place.
Dimming your incandescent lights by 50 percent cuts their consumption in half.
You'll be very disappointed in the energy savings you can achieve by dimming your incandescent lights. When you dim your lights the filament cools and the wavelength shifts more into the infra-red, meaning less visible light and therefore less efficiency. Fluorescent dimming, unfortunately not very common, is more linear and savings are therefore greater.
Washing dishes by hand uses less energy than a dishwasher.
An efficient dishwasher uses less water and electricity than washing dishes by hand. Don't, however, pre-rinse or use the 'rinse hold' feature. Most modern dishwashers don't require it and doing so can waste up to 75 litres of water per load without your dishes being any cleaner. Simply scrape the food off and let the detergents do their job.
Only use the dishwasher once it's full, but take care not to overload it. Turn the heat off during the drying cycle or open the door after rinsing to let the dishes air dry.
Cold water doesn't wash as well as hot water
I never use the hot water cycle, the detergent dissolves completely and my clothes are perfectly clean. About 80 to 85 percent of a washing machine's electricity consumption is used to produce heat.
A shower always uses less water and electricity than a bath.
It usually does, but things are a bit more complex than that.
Obviously, a shower's water and electricity consumption depends on its duration and the type of showerhead you use while you could be filling your bathtub to the brim or only be using a drop.
A bath could use anything from 100 to 200 litres of water while the average four minute shower with an old showerhead uses about 75 litres of water. The same four minute shower using a new, water saving showerhead will use less than 35 litres.
So, while taking a shower should be more efficient it still depends on the showerhead and the duration as well as how hot you like the water.
Computer screensavers save electricity.
According to Climate Savers Computing Initiative, a non-profit organisation started by Google and Intel to help combat climate change, screensavers are not only unnecessary, but they use more electricity than simply allowing the monitor to dim.
When you touch a key or move the mouse the screen pops back in an instant, because the screensaver is a file that is running and doesn't do a thing to save energy.
Sack the screensaver and rather allow your computer to go into sleep mode after the required period of inactivity.
It takes more electricity to turn a computer back on than to simply leave it on.
Wrong! There's virtually no power surge when you switch on your computer and turning it off therefore always saves energy. Also ensure you make extensive use of the power saving features of your computer.
On page two: Electricity saving myths 11 to 20, busted!