Also read the following articles on how you can use less electricity:
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- Bright as a button (Learn how you can stay bright without gobbling up more precious electricity than necessary.)
- Keep it fresh for less (If spiralling electricity costs make you hot under the collar, follow these tips to use less electricity when refrigerating.)
- Heat water, not the sky! (Water heating accounts for 40 percent of household energy use. Here's how you can save...)
- Efficiency myths, busted! (Kabous le Roux debunks 20 patently wrong, yet widely held electricity saving myths...)
- Stay warm for less (How to save electricity (i.e. money!) when warming up this winter...)
There's a solution for monitoring residential electricity usage that involves sophisticated equipment but doesn't require an electrical engineering degree.
Prepaid electricity meters do little more than show available units remaining and their best attempt at revealing the rate of electricity usage is a flashing red LED whose frequency increases with the rate of usage. If you're a homeowner without such a meter, the best you can do is compare your monthly municipal statement with the reading on your analogue meter.
The Efergy wireless electricity usage monitor is a simple solution that provides a far more accurate and sophisticated means for homeowners to monitor and manage their power usage.
I got hold of an Efergy e2 monitoring kit to test in my home. I was pleased to find equipment that has been streamlined to the point where setup requires only a matter of minutes.
The kit consists of a wireless electricity monitor, which is a combination LCD display, wireless receiver and mini-computer. This is the business end of the kit that stores all the data and performs the necessary calculations to make it meaningful.
The second item in the kit is a sensor that plugs into a wireless transmitter. All the devices are battery-powered and never showed any signs of being power hungry during the test.
Finding a main line
Probably the most testing task for any home owner will be to clip the sensor to a one of the mains-supply wires running into the pre-paid electricity meter or board distribution. In some cases this could require removing the panel on the distribution board to get access to the junctions underneath. You could get a qualified electrician to do this for you if you're nervous about playing with the power.
In my case the installation was simple. The mains wires in my house are accessed via a small panel and it was all of 30 seconds work to clip the sensor around one of the wires and switch the transmitter on. The receiver requires the date, time and electricity tariff to be set before it will function usefully. Once again, this task took a matter of seconds.
A flashing LED on the transmitter told me all was well and I simply had to sit back and wait for the receiver to clock up a few days' worth of data.
The monitor provides information on instant data usage in the form of kilowatt-hours or cost-per-hour and this display in itself is a useful tool.
I switched on various appliances in my house and it soon became apparent which items were the energy-sucking culprits. I know that stoves and heaters are some of the most energy-hungry appliances but it was still surprising to watch consumption jump by about 75 percent when I switched on two stove elements and a small heater.
The monitor also has a setting that will warn you with an audible alarm when instant electricity consumption reaches a preset level. This is great for households who want to keep tight control on electricity expenditure because you'll know the second that your usage goes above the level that is acceptable to you.
The receiver was also busy hoarding my usage data while I was poring over its display. After I week I connected the unit via a USB cable to my PC. Using free software I had downloaded from the Efergy website - which was also easy to find and install - I was able to extract seven days information and turn it into meaningful graphs within seconds.
Breaking the habit
With the software I could analyse daily usage patterns and easily see where and when I was drawing the most - or least - power, as well as forecast total electricity costs for the month at current municipal rates.
What I found most useful about the Efergy e2 is that I became far more aware of my electricity usage patterns and that some of my most wasteful activities could be stopped or reined in simply by changing when and how I used certain devices. No fancy or costly extra equipment would be required, just my own self-discipline.
If I had to decide between installing a solar geyser at a cost of between R15 000 to R19 500 or buying the Efergy e2 (priced at about R995), the wireless monitoring device would win hands down every time as my method of getting a guaranteed (and sizable) reduction in energy costs.