People who heat their houses with wood, coal, heating oil, or LP gas generally know how much fuel they consume. They see how often they need to restock, and are reminded of the price each time. Natural gas and electricity, however, are delivered constantly and on demand. That’s convenient for homeowners, but they can lose sight of how much they use.
In order to save on utility costs and reduce your consumption of natural resources, you need a better picture of your energy use habits. Because you directly control most of the appliances and fixtures that use natural gas, you can estimate what percentages are consumed by your range, boiler or furnace, clothes dryer, water heater, and so on. But electrical consumption is harder to guess, and impossible to see.
Until recently, you could review your total use of electricity and estimate how much went to each appliance or fixture. Larger items such as refrigerators and washing machines have carried Energy Star ratings for several years, so their consumption is easier to calculate.
Items like baseboard heaters are also simple to identify as heavy users. Knowing whether your kitchen, family room, or home office used more electricity was pure guesswork.
Thanks to the introduction of recent products, you can now measure your electricity use more accurately. Some show real-time consumption of your entire system to give you immediate feedback on what you’re doing; others measure the rate of consumption so you
know which fixtures use the most current. These devices show where the electricity goes, the way a check register shows where you spend your money. Like check registers, these products give you a starting point for creating a budget and taking control of your household.
Getting the Big Picture
A product called the PowerCost Monitor shows how much electricity your house is consuming in real time. It has two parts: a sensor and a display.
The sensor, which is designed to work with all standard digital and electromechanical meters in North America, is fastened to an existing household utility meter with a ring clamp. Adding the sensor will not change the way the meter works; it is only attached to the outside. The display, which you can place anywhere you like, receives signals wirelessly from the transmitter and shows consumption information in kilowatt hours—and in dollars and cents. The display also shows other information, such as the time and outside temperature.
According to the manufacturer, real-time feedback helps homeowners reduce their consumption of electricity by 10 to 20 percent. As with any measuring device, the PowerCost Monitor only shows the results of your actions; you still have to decide what things you want to do differently. Information from a monitoring system like this can help you determine the effect that different actions will have on power use, and on your electricity bill.
Another whole-house power monitor is called The Energy Detective, or TED. This device reads overall energy consumption from within the house, rather than on a meter mounted to the exterior.
It includes a chart that describes its functions and provides tips on saving energy. The chart shows current electrical use in watt seconds, daily peaks, and totals, as well as monthly usage, in kilowatts and in dollars.
Like the PowerCost Monitor, TED has two parts—a transmitting sensor and a display. The sensor is attached to your electrical service panel, and the receiver with display can be plugged into any outlet in the house. Because installation requires direct contact with the service panel, only qualified homeowners and electricians should install it.
TED also calculates nighttime loads—how much energy is being consumed when switchable appliances are turned off. This shows the consumption rate of appliances and fixtures that remain on all the time.
One more device for measuring electrical consumption, this one from Australia, is the Cent-A-Meter. In addition to electrical current, it displays in-door ambient temperature, humidity, and the equivalent greenhouse gases generated in producing the power consumed. Its functions are similar to those of the PowerCost Monitor and The Energy Detective.
Seeing the Details
A product called the Kill-A-Watt EZ Plug Power Meter measures electricity use by plug-in appliances, showing the rate of consumption in watt hours and kilowatt hours. It goes between an electrical outlet and the appliance it powers, displaying how much electricity
each item consumes. In addition, it measures the quality of your power source by checking the line frequency, voltage, and power factor.
The device also shows running and projected costs. It lets you see what each appliance costs to run for a given period—day, week, month, or year. This lets you distinguish between constant costs for items that run all the time, such as refrigerators, and those you only run some of the time, such as air conditioners.
A similar device called the Watts Up Pro Portable Plug In Power Meter offers roughly the same functions, with optional software that lets you create charts of your electrical use. Like the Kill-A-Watt EZ, the Watts Up Pro shows consumption in watt hours, with automatic conversion for cost, based on a rate you enter. The Watts Up Pro Monitor shows
- Current watts
- Minimum watts
- Maximum watts
- Power factor
- Cumulative watt hours
- Average monthly kilowatt hours
- Tier 2 kilowatt hour threshold (used to calculate secondary kilowatt hour rates)
- Elapsed time
- Cumulative cost
- Average monthly cost
- Line volts
- Minimum volts
- Maximum volts
- Current amperes
- Minimum amperes
- Maximum amperes
- Power cycle
The Watts Up Pro stores data in nonvolatile memory, which you can retrieve even after a power outage. It samples use over time, for up to a thousand data points, so you can download the information to your computer and see trends in your power consumption. You can also export the data in comma-delimited format for use in any spreadsheet program.
Predicting the Future
Because the Kill-A-Watt EZ and Watts Up Pro are portable, you can take them along when you shop for new appliances. If a demonstration model of an appliance you consider buying is plugged in, put the power monitor in the circuit and see how it compares to your existing
appliance. The Watts Up Pro even has a payback calculator that figures the time required for an energy-efficient appliance to pay for itself. It shows monthly savings compared to the purchase price of the new appliance.
All these devices measure the way you use electricity; none will control any appliances or make any decisions for you. Once you have a clear picture of where your energy money goes, though, you will have a much better idea what to do.
