The Power of Plug-In Kilowatt Meters like the P3 "Kill A Watt"...
Strictly speaking they're "kilowatt meters", but most people call them "Kill-A-Watt meters" after the name of the popular brand from P3 International. You plug one between your wall socket and an electrical appliance to find out how much energy the appliance uses.
At home you can plug one into your refrigerator, TV, computer, microwave, electric heater, stereo etc... And at work you can use one to check out the energy consumption of various bits of equipment such as computers, photocopiers, fax machines, and fans.
You'll probably be quite surprised at how much electricity some things use... Believe it or not, some bad electrical items even use energy when they're switched off! These bad items are called "electricity vampires" because they keep sucking electricity until you unplug them or switch them off at the wall.
A plug-in meter will enable you to hunt down these electricity vampires and any other faulty or inefficient equipment that's using more energy than it should... Once you've found the worst offenders you can repair or replace them, or at least take special care to switch them off or unplug them when they're not needed.
Some appliances, such as refrigerators, can cost a small fortune to run if they're a bit worse for wear, so it's very important to check such items every so often to ensure that they're not pouring energy and money down the drain.
Even if you don't find any inefficient equipment, using one of these plug-in electricity usage monitors will almost certainly make you more aware of your energy consumption, and you can use the figures from it to encourage your co-workers or family to be more careful about switching things off when they're not needed.
Where to buy a Kill A Watt
The basic meters are usually pretty cheap, but watch out for hidden shipping charges if you're shopping around for the cheapest list price. You can buy the two most popular models from Amazon:
- The Kill-A-Watt P4400 Meter - this is the basic model that lets you read the instantaneous Watts, Volts, Current, Frequency, Power Factor, and VA, and keeps a running total of kWh (energy consumption) and the total time since the power was switched on.
- The Kill-A-Watt EZ P4460 Meter - this enhanced model does all the above, but also lets you program in the price you pay for electricity so it can keep a running total of cost as well as kWh, and give you projected costs per hour, day, week, month and year. When you have the kWh, calculating these costs is simple enough, but it's pretty handy to have the meter do it for you automatically. The other advantage of the EZ is that it doesn't lose its cumulative totals when it's unplugged or there's a power cut (you have to physically hold the reset button to reset the totals).
(NB Very few places on the web actually explain the differences between these two most popular models. Even P3 International's website makes you hunt through the technical documents to find the differences explained above!)
Amazon's prices are usually very competitive, but it might also be worthwhile to check the prices of these meters on eBay - lots of different vendors sell these meters through eBay (usually "Buy It Now" instead of auction) and you might find them a little cheaper there than at Amazon (above).
Another way to get a power consumption monitor
Kill-A-Watt electricity usage monitors are pretty cheap, and with the current cost of electricity, they don't need to do an awful lot before they've paid for themselves... We think it generally makes economic sense to consider the killawatt meter as a must-have item...
But, if you're not ready or able to buy one, you might be able to get one for free (sort of), as many libraries have a watt meter that you can check out for a short while. It's better to have a meter of your own so that you can check your appliances regularly, but the library option is definitely worth pursuing if buying isn't an option for you.
Kilowatt meters versus degree days
In many ways, checking your electrical consumption with a kilowatt meter is a lot like checking your heating consumption with degree days. With both you're typically trying to find out if your equipment is using too much energy... With degree days it's your heating or cooling equipment; with a kilowatt meter it's your electrical appliances.
However, if you're an energy-saving beginner, and particularly if you have a small building (i.e. not too much equipment to test), there are several reasons why using a kilowatt meter is typically a better starting point than degree-day-based analysis.
- The kilowatt meter is more likely to help you find immediate, actionable energy-saving opportunities. You don't need to collect together your energy bills - you just need to plug the meter between your appliances and your power sockets, find out how much electricity each appliance uses, and then act upon that information.
- With a kilowatt meter it's much more difficult to get misled or confused by the analysis. Degree-day-based calculations are unavoidably approximate, and can easily point people in the wrong direction.
- Per kWh, electricity usually costs a lot more than heating fuels such as gas or oil, and is usually responsible for greater CO2 emissions.
- Many beginners don't have much feel for how much energy a kWh is, and many don't know the difference between a kW and a kWh. Understanding these things is important, and using a kW meter is a fantastic way to figure it all out without having to open a science book...
So, if you want to save energy and reduce your energy bill, we recommend that you get a kilowatt meter before spending too much time analyzing your energy bills using the degree-day data from this site.
It's a question of picking the low-hanging fruit before clambering up a ladder to reach for the rest!