Time to learn what’s watts

Posted by Laura Grant on February 3, 2008
Posted in Green tips, Lifestyle

plugs.jpgWhen Treevolution first read that Eskom and the department of minerals and energy were preparing to send “power police” into the suburbs to gather information about power wasters and to ask residents to report on people who wasted electricity, we thought it was a joke.

But IOL did indeed report that on Friday Eskom had “urged all residents to call their regional offices with information about people who ‘abuse’ electricity in their homes”. It doesn’t actually specify what would constitute power abuse, which is a bit disconcerting. Nor does it say what punishment is likely to be meted out to those caught being wasteful. But one would assume that as long as you’re not running a Laundromat from your back room, or you haven’t got spotlights lighting up every corner of your garden, you’ll be okay. Although you’d better make friends with your neighbours just to be on the safe side.

To help you avoid being snitched by the guy across the street whose yappy dog you’ve been complaining about for years, we’d like to share with you something we found in the City of Cape Town’s Smart Living Handbook on how to conduct an audit of your electrical appliances. As the handbook says: “Knowing how much energy your household uses – and what you’re using it for – will help you to prioritise which areas of energy use you could improve in your home.”

Here’s what you have to do:
Step 1: List the electrical appliances you have in your home
Step 2: Note the power in watts each appliance uses – it’s usually given on the appliance itself
Step 3: Note how long (on average) each appliance is in use per day in hours
Step 4: Work out your daily electricity consumption with the following formula: (Watts x hours per day)/1,000 = daily consumption
Step 5: To get your monthly average, multiply your daily average by 30.

You can put all this information into a table like the one below:

The handbook notes that appliances such as fridges and geysers switch on intermittently, so it estimates that an electric geyser typically uses 2,600 watts for 4.4 hours a day and that a fridge with a freezer uses 158 watts for 5 hours a day. As a matter of interest, a solar geyser with electric backup is estimated to use 2,600 watts for only 1.7 hours a day.

The handbook lists the typical electricity consumption of a number of home appliances, some of the more power-hungry ones are as follows:

Electric stove: 3,000 watts
Hotplate large: 2,400 watts
Kettle: 1,900 watts
Toaster: 1,010 watts
Dishwasher: 1,000 watts
Vacuum cleaner: 1,000 watts
Iron: 980 watts
Washing machine: 3,000 watts @ 0.75 hours per load
Tumble drier: 3,300 watts @ 0.5 hours per load

Now you can try to identify which areas of your home use the most electricity and see if you can come up with ways to save electricity – such as installing a solar geyser or replacing incandescent bulbs with low-energy bulbs. Knowledge is power, as they say.


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