Customer Reviews

3.6 out of 5 stars
Black & Decker EM100B Energy Saver Series Power Monitor
Price:$64.99 + Free shipping with Amazon Prime
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159 of 165 people found the following review helpful
on February 24, 2009
This product was pretty easy to install and setup. I live in a 3-unit condo in San francisco, and the signal transmitted fine from the garage to the master unit, probably 30-40 feet away and through a number of walls.

I'm already an efficiency nut and have replaced all the inefficient fixtures in my house with flourescents, and do a good job turning things off when not in use.

My main issues with this:

- It only measures in 100W increments, so you can't really track how much a compact fluorescent light or anything else small uses. You need to use a Kill-a-Watt or something like that
- The update interval is a bit slower than I would have liked
- There's no good way to get this data off the master unit and charted online
- It seems to be quite inaccurate around 300W. My nighttime usage it says fluctuates between 0 and 0.3 Kwh. I really want to figure out what my zombie devices are and I'm having a hard time figure out why there's always 300W of usage in my house. I unplugged the fridge so it's not that, and I'm using a Kill-a-watt to try and track down everything else
- It does let you figure out how much electricity the big things in your house use like the dishwasher, washing machine, heater, toaster, microwave, vacuum, TV, etc.

What I really want is something I can replace my electrical outlets with and have them communicate with a central server and track usage at each outlet.

For $100 this is a neat device, easy to install, and will find any really bad power usage that you have, but it left me wanting more.

Update: I decided to buy the TED Energy Detective as it's more accurate than this and I have access to my subpanel. That device isn't wireless and I wish it was, looks like there isn't a perfect product on the market yet
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150 of 158 people found the following review helpful
Vine Customer Review of Free Product( What's this? )
Now this is a really interesting product. I have several individual energy monitors that will tell me how much power the device (or several devices on a power strip) are using. But, the real heavy-hitters aren't small appliances, they are the large ones like central air conditioning and electric clothes dryers. Plus, what are all those lights I tend to leave on costing me? I just can't tell that from an individual meter, and my power bill includes everything in the house, so I can't narrow it down.

I investigated various solutions for monitoring how much power my home is using. There are a couple of them out there. They are pretty expensive (hundreds of dollars), and they need to be installed by an electrician (there's a pretty big risk of death if you don't know what you are doing).

When this one came along I was interested, but I figured it would be pretty similar to the other ones. Luckily, it differs in two important respects. It is easy to install, and it is much cheaper. Installation consists of putting a battery-powered transmitter on the outside meter. The meter doesn't need to be opened, and it isn't directly attached, so you won't need an electrician. On my meter, which is electronic, it interfaces with it by blinking a light into a little port that is on the meter and reading the response. It works with mechanical meters as well, by sensing the little wheel turning inside the meter. I suspect this is more accurate than the type that connects directly to the power lines, as the meter is what the power company is basing your consumption and cost. I also like the fact that I can't die from attaching it. The downside is that it has a battery that needs regular replacement. The manufacturer recommends lithium AAs for the outside sensor, and those aren't cheap. I'm not sure how long it lasts, but I have several wireless outdoor temperature sensors that go at least a year on a set of standard alkaline batteries, so if it lasts a couple of years on lithiums I'll be happy. Still, it would have been nice of them to throw a set of batteries in the box, even if they had to raise the price a bit to do so.

The display unit, which goes inside and gets information from the wireless sender unit outside on the power meter, is very clear and easy to use. It displays the current energy use along with the month to date cost (you tell it what your power rate is during setup), along with the outside temperature. The amount of money the power is costing is a lot more useful than how many kilowatts are being used, so I was pleased to see that it does the calculation for me. The only hard part here is that you have to do some math from your last bill to determine how much each kilowatt is costing you, but that wasn't especially hard to calculate. They do tell you how to do that in the instructions, but my bill didn't look much like their example so I had to puzzle it out.

One thing I really wished for is a computer interface with graphing software. I wasn't expecting it at this price point, but that would be a great feature. Nothing beats looking at a color-coded graph for seeing where your peak electrical use is happening, and what is causing it. Tie that in with outside temperature, and it is easier to determine how much power is going to the heating and cooling systems during seasonal changes. Maybe they'll release a "pro" version that has that.

Overall, this is an interesting, easy to use, and reasonably priced item. If it helps you lower your energy bill even a little bit each month, it won't be hard to justify the purchase. Plus, now I know that leaving my kitchen lights on all the time is costing me eight cents an hour!


Sean P. Logue, 2008
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61 of 64 people found the following review helpful
TOP 1000 REVIEWERon October 2, 2008
Vine Customer Review of Free Product( What's this? )
After viewing the product image and seeing the name, I assumed that this product was Black and Decker's take on the Kill A Watt. The Kill A Watt, by P3 International, is a popular device used to measure the energy consumption of a single device. To use it, a device is simply plugged into it, while it is plugged into the wall. The reason I explain this is because, while my initial assumption was incorrect, these products both compete and bolster each other in ways I will explain below.

The Black and Decker Energy Power Monitor is a very interesting device. It consists of an outdoor unit, which attaches to an electric meter, and an indoor unit, which displays and interprets data collected by the outdoor unit. The reviews here seem to conflict about the ease of installation of the outdoor unit. My experience was extremely positive. All I had to do was extend the sensor by pulling a lever and tighten it onto the the electric meter's glass dome with a flathead screwdriver. My electric meter is the old fashioned electromechanical (spinning disc) type, which may explain the relatively fast and painless installation. The indoor unit feels surprisingly high quality, despite being all plastic, with very durable buttons and some heft. As a bonus, they have also included an outdoor temperature reading. The display is very nice and large, but the low resolution, which is similar to a digital clock, limits the amount and type of information available.

And that is where the caveat lies for me. Given this very powerful method of reading energy use and broadcasting it long-range wirelessly, one might expect a plethora of data and the ability to monitor various aspects of energy usage over the course of weeks, months, and years. Unfortunately, that is not the case, but what is offered is the core components needed to derive that data in a simple and fun format. Two main screens can be toggled between, with one showing the energy usage in terms of cost and the other in terms of electricity used. The "Cost View" gives the estimated amount of money spent per hour, updating itself every thirty seconds. So, you might unplug an appliance and check if a substantial difference is made in the hourly cost. Monthly cost can also be estimated. There is also a "clr" button to clear all costs and find the accumulated cost since it was hit. The "Power View" essentially displays the same information, but in kilowatts rather than dollars. For example, the amount of kilowatts used in a month can be estimated.

While these tools are powerful, I found that the lack of a way to track that data over time diminished their value to some degree. I think that a simpler question is how much electricity a single device consumes, which can be used to understand if the device is worth the cost and if upgrading to a more energy efficient version would be sensible. Thankfully, the device can do just that via the "tare" button. If you use a scale to measure food, you are probably familiar with taring. In that case, you put a bowl on the scale, hit tare, and then put the food in the bowl to weigh it. By taring the bowl, you make sure that the bowl's weight is not counted, because you only want to weigh the food. In the same way, the Power Monitor's tare simply subtracts whatever energy is currently being used. So, if I wanted to see how much energy my dryer is using, I would hit tare, then turn it on. This is great, because unlike the Kill A Watt, it doesn't matter that I am measuring a 240V device. Unfortunately, any deviation in power, such as a refrigerator popping on to cool or a heating unit turning on and off, will lessen the accuracy of the reading because it was not taken into account by the tare.

So, the much less expensive Kill A Watt is superior for measurement of power used from a single 120V device. However, the standard version does not have the ability to measure some of the most power hungry devices, such as a dryer, oven, or air conditioner. That is where the Power Monitor shines. Despite my criticisms related to the lack of tracking options, which could have been simply alleviated with a computer interface and basic software, it is a very solid and valuable product that I would highly recommend. A "best of both worlds" device would consist of small Kill A Watt type devices that could be individually identified and communicate with a central hub. In this way, power usage for each member of the family could be quantified and the total energy use from all devices could be compared with the reading at the electric meter to check for energy leaks, which can also be costly and will not be revealed by either device alone. Certainly, this is far too much to ask from a device in this price range, but I look forward to future innovations from the company and applaud this solid step into the arena.
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125 of 137 people found the following review helpful
TOP 100 REVIEWERVINE VOICEon September 24, 2008
Vine Customer Review of Free Product( What's this? )
I a very impressed with the Black and Decker Power Monitor. It is a perfect tool in helping you determine how much energy you are using each day. While I would not buy this device in order to "save" money (it will take many months for your to recoup the cost on the energy monitor) however, it is a great way to fid out how much energy your house uses.

Examlple - when my air condition comes on I see that I pull an additional 3000W which translates into about 0.20 cents per hour. Leaving my kitchen lights on is about 200W or about 2 cents an hour. The Black and Decker Power monitor makes it easy to track your energy footprint and what are your big energy items.

If you want to save "money" my suggestion is to replace your incandescent lights with flourescent (or however it is spelled) this will save you about 30%. However, if you want to find modest savings while reducing your unneeded energy consumption this is the item for you. 5 stars

PS - installation is not "Easy" but it can be done with the use of some trial-and-error... budget about an hour.
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29 of 29 people found the following review helpful
Vine Customer Review of Free Product( What's this? )
The Black and Decker two piece system has a wireless unit that you install on your electric power meter. It attempts to read the meter and return the real time power usage for your entire house. You enter numbers from your electric bill and it tells you in dollars per hour how much you are using (there are other modes as well).

I was frustrated at first with trying to get the wireless unit on the power meter correctly. It kept losing the signal. I eventually got it pretty good, but it's not perfect. I finally decided that this isn't a perfect real time thing. It's just an extremely accurate estimate. Using it that way, it was a lot less frustrating. I have a mechanical meter and it also works on the optical ones, so they may work better.

Using the unit, I was able to see how much power my central air uses (35 to 40 cents an hour), my dishwasher (10 cents an hour) and my big set of basement light (12 cents an hour before I switched a few more bulbs to CFLs then 8 cents). Just having the unit where I can see it has helped me change habits and turn things off and switch my computers so they go into standby mode faster.

- Install batteries (not included). You may want lithium ones for the external unit if it gets below freezing in your area.
- Install external optical reader on your power meter. Wash the meter off first.
- Adjust meter reader until you get a good connection that doesn't drop.
- Grab one of your electric bills and enter some data into the readout unit. The unit uses this to calculate you hourly electric price.
- See how much power your entire house is using.
- Turn things off and on and see how much power they take.

- Lets you know your "whole house" power footprint.
- Having the unit on where you can see it keeps you aware of the fact you are using power and helps you remember to turn things off.
- Helps you track down just why your electric bill is what it is.
- Fun for gadget geeks.
- Very cool way to know how much power appliances like central air and hard wired lights take.
- The Tare function make it really easy to isolate things like the dishwasher and central air. Hit the tare button then turn on the appliance. You get to see how much power that appliance is taking (plus any other things that were off when you hit tare and then kick in after).
- Includes an outdoor temperature reading.

- Hard to get it perfect on a mechanical meter. It took a lot of goofing around to get it to keep working. It still drops out a little from time to time.
- The sunlight will interfere with the optical reader when it hits just right.
- Once you know how much power all the appliances in your house take, you don't really need this anymore.
- A little pricey, but maybe you could share it with friends or neighbors.
- No computer interface for graphing interpreting results.

- Don't remove the big white tag. It's a note to the meter reader.
- Make sure to clean your meter with glass cleaner before installing the optical reader like it says in the instructions. It does help.
- Even though this unit attempts to read "actual" usage, it is not perfect. It should still be considered just a really good estimation.

Update: 3-29-2009 - I've come to really like this unit. I've hung it on the wall next to the thermostat. I like to glance at it daily to see energy useage. I've turned off an old computer that we kept on daily and our price per hour has gone down. I am also switching to CFLs where possible.

Update: 5-10-2009 - I was working in the garage when I guy came by and asked if I was the home owner. He was the meter reader and asked about the unit on my meter. I thought I was in trouble, but he had no problem with it. He wanted to know about it. I showed him the indoor unit and he thought it was great! He said he wanted one too!!!

Update 9-12-2011 - Still working great and I really like it. Got a new furnace and A/C and can really see the power difference. I think this is a must for the modern home.
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30 of 32 people found the following review helpful
Vine Customer Review of Free Product( What's this? )
There are 3 different types of electrical meters. Even the old dial style has an optical post on the face. Type 3 meters has one on the top. Look for a small round protruding pipe which is an optical port with an LED (Light Emitting Diode) in it. It is constantly transmitting your real time electrical usage. Why not tap into that resource, and be able to go through your home with a hand portable receiving unit, which also has a snap on desktop base, so you can monitor usage on the fly.

The refrigerator kicks on and you can instantly see what a difference that makes in your dollars, or Kw usage. Maybe the old fridge is costing you more per month in electricity than the payments for a new more efficient one, or maybe not? How do you know? Black and Decker Power Monitor to the rescue. It even does the calculations for you. Input the numbers off of your electrical bill once, and wah lah, you have the dollars and cents of it show up right on your screen.

Setting it up seems like a few minutes, but in reality it takes you more like an hour, but everything is easy. The instruction manual takes you through it with illustrations.
1) This is how you strap the sensor to your outside meter; including how to get it centered over your optical out LED. Once centered the sensor starts to blink, and then you tighten it down; done.
2) Then you want to determine your billing mode; peak/off peak, tiered, or flat rate billing, and the billing individual rates, which are printed in a column on your electrical bill; for example, generation charges 0.06840 + transitions charges .00560, plus distribution, and transition charges. If you add up all of those individual rates, the total sum is your total cost per kilowatt hour; then multiply that by 100 and you get your "billing rate". Keep that number handy for when you program your main unit, they refer to as your digital display.

Other than that all you need is your "Power factor", which is a number printed on the meter; e.g. usually 7.2Kh for an electro-mechanical meter, or 1.0Kh for an electronic meter. You can go outside and see what yours says; it is printed on the face.

So armed with your "Billing rate" number, and your "Power factor" printed on your meters face, you simply hit the program sync button on the top of the digital display, and enter the information when it asks you for it, as well as the day of the week, and the time, and your done. The manual walks you through all of this step by step.

The first time you go through the setup, as you read each part, you will say, "Oh I see". After you do one, you will say, "I could install another one of these in less than 3 minutes".

The Power Monitor will show you; Your current electrical usage, the usage of a single electrical appliance, your accumulated electricity usage over an hour, a day, or any time period, and your estimated monthly usage.

So to summarize; you may be using some devices like a small electric space heater in a bedroom, that you discover is consuming $50 per month worth of electricity, and you computer monitor plus a couple of light bulbs are only drawing 1 or 2 cents per hour. It is all at your fingertips. With the 2 double A battery driven digital display, you can sit in your armchair, and continually know what the total per penny/per hour usage is costing you. If someone is using something that costs you a fortune, within 30 seconds (the refresh results rate) of when they turn it on you know it. On the other hand you know when to not sweat the small stuff, and just what that small stuff is.

I don't know whether to place this in the "something for somebody who already has everything" category, or something for the frugal who want to put a lid on wasteful spending. Month after month, year after year amounts can really add up, especially if you don't know where the leaks are. For the latter it will more than pay for itself after a few months. Overall highly recommended. Well designed, engineered, and setup is a breeze as long as you do it one step at a time.
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13 of 13 people found the following review helpful
Vine Customer Review of Free Product( What's this? )
I've been using this for about a month now and have been very impressed since day 1 with the usefulness of this power monitor. If you are looking to get a handle on what things in your house cost to run (hot water heater, air conditioner, dishwasher, entertainment center) this is a great gadget to get a handle on actual costs. Additionally, the outside temperature meter has come in useful this Fall here in Florida. I'm able to see when the temperature dips to a comfortable level so I can turn off the air conditioner and open the windows. I can now hear my neighbors air conditioners kicking on and off all day while my windows stay open with a cool breeze blowing around the house.

I am on a tiered system here, the first 1000 kWh are billed at 9.9 cents per kWh and above 1000 kWh I'm billed at 11.9 cents per kWh, so I just input 10.9 to keep things simple. I generally stay around 1000-2000 depending upon the season, and August as usual finished up on the high end.

I found out that when the water heater or air conditioner are running it costs me about 50 cents per hour. Of course, they don't run for nearly an hour at a time, but it was interesting to find out that these are the biggest energy black holes in my house. The washer and dryer surprisingly used far less energy, about 12 cents per hour each. Fans and lighting were less than a penny, even when all were turned on at the same time. I do use General Electric 97659 13-Watt (60 Watt equivalent) Energy Smart Soft White Spiral T3 Light Bulb 6-Pack throughout the house, including bathroom vanities, overhead spotlighting, lamps, outdoor lighting, and even our dining room chandelier with upturned lamps. I switched over to CF bulbs completely over a year ago and estimate that alone saves me over $20 per month.

Knowing the outside temperature allowed me to open the windows sooner and has probably saved me $40 over the past month. More than those things though, just being aware of what various things cost to run by isolating them through the tare function has motivated my children to turn off their lights, stereos, TVs, and more to keep costs down.

This tool brings real world costs to the appliances and other electrical items we run daily without any guesswork.

Although the cost is a bit high, I would expect that you could easily see the cost savings in under a year. It's fun to experiment and see what the washer costs to run using cold vs. using warm/hot. Running it with cold water is a huge cost savings because you are no longer running the hot water heater as well as the washer. That is something I had never really given much thought to in the past. I haven't done a cost comparison, but I expect that it's less expensive to buy cold water detergent and run your washer on cold rather than normal detergent and running your washer on warm.

I will caution you though that the batteries run out fast! We put rechargeable batteries in and within 2 weeks they needed recharging. The manufacturer recommends lithium batteries for longer battery life.

If you are looking for an energy monitor, a competing product is the P3 International P4460 Kill A Watt EZ Electricity Usage Monitor. I have both. The Kill A Watt was useful, but now that I have the Black and Decker EM100B, I no longer use the Kill A Watt. The Kill A Watt is limiting in that many products, especially the big energy hogs do not have traditional plugs or are in hard to reach areas, so not everything can be measured. Additionally, the Kill A Watt takes time to monitor your energy usage, and only monitors one appliance at a time, so it would take months to move it around the house to gauge everything.

Spend the extra money and get the Black and Decker EM100B. You'll have instant results, power usage estimates, cost estimates, and individual appliance cost of operations.
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10 of 10 people found the following review helpful
VINE VOICEon October 14, 2008
Vine Customer Review of Free Product( What's this? )
I better give a little more info on how this hooks up to your meter. The sensor straps on to your power meter with a hose-clamp. It doesn't look as horrible as that sounded. It looks cool. There is a sensor on an arm that sits over the spinning mechanical wheel on your meter, or over the little IR port on the meter. It works on many different styles of meter, which is something I was a little worried about.

The box and meter claims it will help you save money on power. Well, it will not directly save you money. It helps you see what things are using a WHOLE lot of power, so you can save money by knowing what things you should turn off or replace because they are costing a whole lot.

You will want to make sure your power meter is within 30 meters (if I remember correctly) of where you can use the remote hand-held unit. I was really worried it would have issues with my wireless networks, but this uses a 400 MHz range signal, so it works great along side my wireless devices, with no interference! That was relief!

I really have to say, this is the greatest power metering device I have found yet! I have been using other devices, that meter individual outlets, but have been wishing for this item for a long time now!

You can program it for your power plan, whether you have peak hours that cost more (like me) or a different plan structure. The meter shows you how many watts used (in kilowatts) with a 100 watt resolution. It will also show you how much power you are using by price, say, $1.20 per hour for instance. You can see how much your A/C is costing you when it turns on. It has a "Tare" button so you can temporarily set it to zero, and turn something on and see how much power that item is using, instead of doing the math.

The Meter sensor uses 2 'AA' batteries, and so does the hand-held unit. They can not be turned off, and run constantly, but I have been going for quite a long time on normal batteries. When you connect the unit, it starts metering from that point. It will not match your power bill exactly, unless you reset it at the time your meter gets read every month. I really love this handy tool!
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13 of 14 people found the following review helpful
on January 20, 2010
I purchased Power Monitor about 5 months ago and it's never worked for more than a week a time. The unit that goes on the meter continually malfunctions. At best it worked for a week before needing to be adjusted and resynchronized. This happened continually. The monitor itself operates in the same band that all of the remote reading thermometers and weather stations use and if you have one of these in your home it interferes with the power monitor. I actually had to put the power monitor about two feet from the meter unit for it to operate - when it was working. I was really disappointed with the unit and had I known what a poorly designed product it was I would not have wasted my money.
Bill S
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9 of 9 people found the following review helpful
on October 27, 2008
I have a Blue Line power monitor. They look so much alike, that I'd suspect they are both made by the same manufacturer. Anyway, my pet peeve with my power bill is that it's like a credit card. Once a month you say ouch and then forget about it. This thing is a constant reminder. My wife bought in immediately. It lives in the center of our house and the wife and I reference it constantly. Instant gratification. Turn off the air conditioning and watch the # get smaller.
I don't have teenagers, but I suspect that they would buy into this thing.
I used 30% less Kilowatts this summer. My power bills have a tiered rate system, so the actual $ savings was more than 50%. Paid for itself this summer. Now it's all gravy and I've got a much better understanding of my power usage.
I was without it for 24 hours (didn't have new batteries to put in the sending unit - yes it had been warning me for a week) and I felt naked.
Like my uncle said about his TIVO, there are 2 kinds of people in this world. Those with a power monitor and those who don't know about it yet.
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