Any time you’re using electric devices with high power draw, you may want a way to keep tabs on your actual power use. Usually, this is hard to quantify. For example, many consumer electronics use what’s called “phantom power”. Even when they’re turned off, they’re still running up your power bill. It can be hard to find the source of phantom power.
Additionally, you’ve probably got a number of appliances in your home that operate on a cycle. Sure, you know that your clothes dryer is 500 watts, but what does that work out to yearly, when you’re only running it for a few hours a week?
Whether you’re just looking to take a quick at-a-glance reading, or estimate your monthly bill, an electricity usage meter is the solution. These handy little devices are manufactured for a wide variety of purposes, each of them with their own specific design. Let’s take a look at the three best electricity usage meters on the market. Then, we’ll help you find the one that’s right for you.
P3 International ‘Kill a Watt’ EZ Electricity Usage Monitor
The P3 International ‘Kill a Watt’ is perhaps one of the best known on the market. The manufacturer was one of the first to publicize issues such about phantom power draw and provide a solution for consumers who were concerned about it.
As you can tell from the design, the P3 International ‘Kill a Watt’ Electricity Monitor hasn’t changed in many years. While it might not be the most modern looking power meter, it’s one of the most well-known and reliable devices on the market. The design is simple and functional. It’s about 5 inches tall, 2.5 inches wide, and sticks out from the wall a little more than in inch when plugged in. On the top, you’ve got a large LCD display that gives you real time readings about your power use, with a number of easy to access controls below it. The bottom is occupied mostly by the standard 120V outlet. Other than that, this meter is pretty simple in design. Let’s see how it performs.
Just below the LCD display, you’ve got four buttons. Each of these buttons changes the information that is displayed on the screen. Kilowatt hours (kWh), the measure of energy consumption over time, are always being recorded. The other buttons are handy if you want to have real-time information about the quantity and quality of electricity that is being used. You can measure voltage, amperage, watts, and the frequency.
To start it up, it’s as easy as plugging it into the wall, then plugging in the device you want to measure. To test it out, we plugged it into our home theater system in the living room. This means that we had a power bar connected to it with a flat screen TV and small stereo system. The first reading we got was 121.5V. This is pretty standard for the American power system, and seems pretty accurate. The important thing is that this meter provides us with the RMS voltage. Since AC electricity is constantly in flux, getting an average reading is tricky. RMS voltage is a mathematical formula that shows the true DC equivalent voltage, and the only true way to read power.
Scrolling through the settings, we found that our home theater was using 45 watts of power at 60.01Hz. But the value we really wanted to see was the kWh reading. This is the value the electricity company uses to calculate our bill, making this the money reading. Later in the day, we saw that we had used 0.12 kWh. The timer showed that it had been reading for 4 hours. You can easily multiply this number by your power cost and find out exactly how your electronic devices have cost you.
The real question is how accurate are these readings? Without a more accurate meter, it can be hard to tell. However, the P3 International Kill a Watt Meter has been on the market for a very long time. It’s been tested by several independent bodies and found to be one of the most accurate meters on the market. On paper, it’s shown to have only 0.2% error in most readings, which is an excellent value. While there are not a lot of extras, this electricity use meter is among the best on the market.
Belkin Conserve Insight Energy Use Monitor
Belkin is a company that’s well-known for their high-quality products sold at a generally affordable price. With their power meter, they’ve taken a classic idea and put a modern twist on it.
The Belkin Conserve Insight is one of the most attractive energy use monitors that we’ve seen. It’s got an attractive, modern face that wouldn’t appear out of place on any desk or table. But the best design element of this unit is the remote display. Often, our plugs are tucked in behind shelves or other furniture. In this case, how are we supposed to get our readings? With the Belkin Conserve Insight, it’s simple. The display is attached to a long cable that allows it to be placed out on a desk somewhere. This way, your readings are just a quick glance away. The display is much more compact than other units, although it’s still clear to see your readings. On the bottom of the display, you’ve got three buttons, each of which toggle a different reading.
There are three types of information provided. Of course, your power use in kWh is going to be the most useful. By tapping the power button, you are able to scroll through a few different options. You can see your actual measured use to date, estimated monthly use, or estimated yearly use. This meter is pretty smart, so this estimation will get more accurate over time. For example, when you first plug it in, the meter is going to assume that whatever you have connected to it is in use 24 hours a day. But after a few days, it will know how long you use it for each day. This allows it to estimate your average daily, monthly, and yearly use.
Its other readings are focused on the “why” instead of the “what”. We all know that there are repercussions to our power use. Some of these are environmental, others are financial. If you tap the $ button, you’ll be given the same daily, monthly, and yearly values you get for power. But instead of showing your power draw, it will tell you the cost for the electricity. It comes pre-loaded with the average power cost for the United States, but this is easy to enter directly from your bill. Finally, it can also display your estimated carbon footprint. Of course, this is just a rough estimate. Your actual carbon footprint depends on where you live, and how your power is being generated. But it is nice to have a quantification of your environmental impact.
Getting the Belkin Conserve Insight up and running is very easy. Just plug it into the outlet, then plug your device in. From this point, you are ready to start reading. If you’re interested in measuring the cost of your power, you’ll need a copy of your bill and a few minutes of time. You have to hold down the $ button for about 20 seconds. Then, the display will flash showing the value followed by HWK. You can use the buttons on either side to increase or decrease this value. The only disadvantage of this system is that it doesn’t separate peak cost from regular cost.
Most power companies charge you more during certain hours of the day. Since it’s averaged, you’ll still get a measurement that is roughly accurate, but not completely. Since these values can change from month to month, it’s unlikely that you’ll ever find a meter that’s totally accurate in this department.
Kuman LCD Display Plug Power Meter
Kuman is a lesser-known manufacturer that makes affordable versions of common electronic devices. They’ve received excellent reviews, so we’re excited to see how it stacks up.
The Kuman LCD Display Plug Power Meter looks like an updated version of the Kill a Watt. It’s got a nice large display, with the handy addition of backlighting. There are some minor navigational changes to the buttons, and the case is a little more rounded. But overall, it’s a pretty simple design.
In many ways, this meter combines the best features from the other two meters. You’ve got all the base measurements that you want from a meter. It tracks power (watts), energy (kWh), voltage, current (Amps), and Power Factor (Watt estimation).
kWh is measured on a daily basis. Each 24-hour period, the display will be updated to show your cumulative power use. You can also see the current day’s measurement, with a timer at the top that shows how long it’s been since the last reset.
The one thing it has that the Kill a Watt doesn’t is a way to track your power cost. By entering your price per kWh, it can calculate your monthly bill before it arrives in the mail.
Using this meter is very simple. The first time you plug it in, you’ll be prompted to enter your electricity cost. It will be pre-filled with the national standard, so if you are not too concerned with this value you can just hit next. But if you are, it only takes a matter of seconds to enter the value. Once you’ve done that, usage is generally the same as any other meter. The one key difference is the inclusion of a backup battery. If you move the meter, you won’t lose all of your measurements.
The one area this meter doesn’t perform well in is accuracy. While the Kill a Watt is accurate to 0.2%, this one has up to 3% error. For most consumers, this is not actually that big of an issue. But it is marketed for industrial use. If you’re using very high power consumption devices, 3% can add up a lot over time.
Which Electricity Meter is Right for Me?
All of these are great electricity meters in their own regard, but there are a few key differences that you should be aware of.
For consumer electronics, the Belkin Conserve Insight is the best option. It’s designed for low power electronics, and provides information that is just as handy as it is useful. For your home theater, computer, or any other gadget you own, it’s really a great choice. We’re big fans of how it operates and the easy design that allows you to see the monitor even when the outlet is crammed in a tight space.
If you’re concerned about powerful devices like your fridge, stove, or other appliances, then the P3 International ‘Kill a Watt’ is your best choice. They’ve been selling the same model for years, and for good reason. It can handle the high power draw of large devices, with unparalleled accuracy.
The Kuman LCD Display Plug Power Meter is an adequate replacement for the Kill a Watt. It’s not quite as accurate, but it does have a battery. This means that you can carry it around, quickly doing spot checks on a number of different devices. If you’re not going to be installing your electricity meter in a permanent capacity, this will save you both money and time.