Do Energy Monitors Really Work?

In the discussion about whether or not a home energy monitoring device works or not, some readers mentioned that they had bought and used the Kill A Watt Electricity Usage Monitor as a way to check energy usage (and then adjust habits accordingly to save money.) So when I ran into Consumer Reports' review of both the P3 International P4400 Kill A Watt Electricity Usage Monitor and the Watts Up AC Power Meter, I was quite interested to see what they said. Here's their bottom line:

P3 International P4400 Kill A Watt Electricity Usage Monitor and Watts Up AC Power Meter were accurate, and both can teach you how much an appliance contributes to utility costs. If that makes you use the appliance less or at lower-cost times of day (ask your utility when those are), you could save money. The devices can also help you compare energy costs of an appliance you own now with projected costs listed on any new one you might buy.

I haven't used either of these items (or anything like them), but I'm thinking it's probably a good investment. Those of you who have used these, what do you say?

Comments

[Raj]

I used my kill-a-watt religiously for the first couple months. Determined that my projector + sound system wasn't costing me as much as I worried it would. Then after that I just let it go. I think it's still plugged into the home theater, but I haven't touched it in about 9 months.

[Recycleholic]

I have used the Kill A Watt off an on. It doesn't give you the dollar expenses but it gives you the numbers you need to compute how much it costs you to run appliances.

I did learn that it costs me about $500 to run my dehumidifier in my basement during the summer months. As a result I put it on a timer to run only during off-peak hours and that saved me alot of money.

[Andie]

When we got married and my husband moved into my apt, the electricity bill doubled and I was horrified. He came with a lot of electronics.

We got a kill-a-watt, replaced our light bulbs with CFs and have been able to get things more under control. The kill-a-watt gave us information we needed to make more informed choices about the electronics we currently had and the energy use of new electronics.

We've found it to be pretty helpful. We've replaced his server motherboard with one that uses less energy. We're more conscious about powering down our computers when they aren't in use. Alot of our electronics are on power strips that have 2 dedicated-on outlets and the rest can be completely powered down so that there's no passive energy use. Probably the next big thing to replace would be the amplifier, but that's its own big ticket item so we're not in a hurry about that.

Even though our bill is still higher than I would like it to be, it's not double anymore.

Like another poster said, we're not using the kill-a-watt all the time. But we do check things out when they first come into the house so that we can return them if we're surprised by the amount of power they use.

[Rob Lewis]

I've used a tool called an OWL here in the U.K. which does a similar thing, and I've found it reasonably useful for seeing which appliances use the most electricity and cost us the most money. It gives us a baseline, such as an average daily cost, from which we can try and reduce our electricity usage.

I posted a little about it here: http://money-watch.co.uk/4876/track-electricity-usage-owl

Have you also heard about Google's plans for helping you keep track of your energy usage? http://www.isedb.com/db/articles/1991/1/Google-Develops-Power-Meter-to-Analyze-Home-Energy-Consumption/Page1.html

Could be quite interesting.

[Terry]

I have a Kill-a-Watt and find it very useful. Not only does it help me figure out how much some of my power hungry devices use, it was it also very useful for getting power readings of several things so I can calculate how much I can run on my generator (or even my power inverter). While it is not responsive enough to catch startup current, I get a good read on my run current and can "guess" the startup needed.

If you really want a good read on your power usage in my opinion, do what I did - get a good clamp meter. I read the current draw on each main, then each leg in the fuse box (but please know what you are doing first!). I did it with all the lights/tvs/appliances/etc on like a normal night, then turned everything off and got a "sleep time" reading. Then I turned off everything I could find and found the devices sucking power for no good reason. I kept going through this until I had everything I could find and was down to a few hundred watts - which was things like doorbells and X-10 light modules that I was able to pretty much identify by turning off the breakers one by one.

I have done this a couple of time and kept a log of my readings. I have a very good handle on how much I am pulling and it was a very good education. It is interesting how much power I have saved by doing a few simple things.

Good luck!

[Emily @ Taking Charge]

I actually heard a thing on NPR this afternoon about home energy use, and the tech expert (ironically the tech columnist for my city newspaper, the Austin American-Statesman) said he definitely does recommend the Killawat to help figure out how much energy you're consuming. I've read in many places that things that are plugged in but off use "phantom" or "vampire" power and that everything should be unplugged if not in use (if possible). I try to unplug my microwave and chargers and things if I'm leaving for a few days, but I'm terrible on a day-to-day basis...I know I'm supposed to turn my laptop off every night, but I always leave it on. Oops. Maybe I do need a Killawat....

[Mark]

Ask your local library or utility company if they have a kill-a-watt to checkout.

[BV]

"When we got married and my husband moved into my apt, the electricity bill doubled and I was horrified. He came with a lot of electronics."

Funny, that's the exact same situation I found myself in when I got married and moved in with my wife. I came with a lot of home theater and computer equipment and the electric bill went through the roof for her, although it stayed roughly the same for me. I didn't understand the panic until I saw what she had been paying before I moved in.

Buying on of these Kill-a-watt boxes has been on my TODO list for a while. However, I'm hoping that one of my friends or family already have one that I can borrow for a few weeks. While I don't mind spending money to save money in the long run, I have a feeling that this is the type of device that gets used a lot up front and then sits in a closet for the rest of its life.

[Cheap Like Me]

I agree with BV that if you can borrow one, it's great. I bought a Kill-a-Watt and I think it has pretty much paid for itself -- I realized that our beloved fancy coffee maker was using almost as much electricity as our refrigerator! (It's a Bunn with a hot water reservoir that makes amazing brewed coffee in 3 minutes.) As a result, I put the coffee pot on a timer so it runs for 1 hour in the morning (and is heated up for our coffee), rather than running 24 hours a day. I calculated that we should save about $35 a year.

I read someplace that some communities allow people to check out electricity monitors from their utility or their library, which is a wonderful idea -- it's not necessarily a tool you need at all times.

[Rob]

I have been meaning to get one especially now that I just bought a house. Any of you who have one just sitting around want to sell it? Let me know!