Reading your electric meter helps rein in energy use

It wasn't too many years ago that the speed of that revolving disc on your electric meter was unimportant - a whim of childhood. Today it is a very different story.

Each revolution of the disc means more money out of pocket. Homeowners now keep an eye on their electric meters with the hope of slowing, rather than accelerating, their pace.

Indeed, meter reading has become one way families can gauge home-energy consumption. By reading both the gas and electric meters, families can monitor the effectiveness of energy-conservation efforts. Meter reading, in fact, is a simple exercise, involving only a few basic rules.

The basics

An electric meter records the number of kilowatt-hours of electricity used in a home. A kilowatt-hour is the energy delivered by an hour-long flow of one kilowatt, or 1,000 watts, of electricity.

Gas meters show the total volume of natural gas that has been delivered to your home and consumed. Gas is measured by its volume and is described in cubic feet.

Most gas and electric meters have a series of four dials on the face of the machines. Each dial has a pointer which moves either clockwise or counterclockwise. When taking a reading, these dials should be read from left to right.

The rules

If the pointer on a dial of an electric meter is between two numbers, read the smaller number.

When the indicator is pointed directly at a number, look at the dial to the right. If the pointer on that dial has not yet passed zero, then record the smaller number indicated on the dial to the left. But if the pointer on the dial to the right has passed zero, then record the number that the pointer of the left-hand dial is resting on.

Here's an example: If the pointer on the first dial (the left-hand dial) is between 9 and 0, record 9 as the first number in the reading. Nine, in this case , is the smaller number since zero represents 10.

Similarly, if the pointer on the second dial is between 5 and 4, record 4 as the second number in the reading.

But if the pointer on the third dial is directly on 5, look at the dial on the right. Suppose the pointer on that dial rests between 9 and 0. According to the rule, the reading on the third dial is 4.

The fourth dial, with the pointer between 9 and 0, is then read as 9. Thus, the total reading in this example is 9449.

Readings on utility meters are cumulative totals. In the example above, the meter, since it was last set at 0, has recorded the use of 9449 kilowatt-hours of electricity.

Gas meters are read according to the same rules used to read electric meters. The only difference is that the final reading from a gas meter must be multiplied by 100 to obtain the total volume of gas consumed.

Apply your meter-reading skills

* To find monthly utility use, take two readings a month apart and subtract the earlier reading from the later one.

* To estimate how much gas or electricity your heating system uses, read the meter immediately after your family goes to bed and again before arising the next morning. Readings taken while a family sleeps assures that lights and appliances, except clocks and the refrigerator and/or freezer, will not be running during that time.

Subtract the evening reading from the morning reading to determine how much energy was consumed in heating your house during the night. Then divide that number by the number of hours between readings to find the average number of kilowatt-hours of electricity or cubic feet of gas used per hour.

* To assess the energy consumption of an air-conditioner, take an initial reading while the unit is running. Take a second reading an hour later. Subtracting the earlier reading from the later reading will yield the amount of energy used in that hour.

Next, turn off the air conditioner and take an initial reading. Then, with the unit still off, take another reading an hour later. Find the difference between these two numbers.

Finally, subtract the number obtained while the air conditioner was off from the number recorded when the unit was operating.

* To judge the effectiveness of your family's conservation efforts, take readings for several weeks during peak hours of utility use before any improvements are made. Try to include at least one set of weekend readings. After completing conservation measures, take the same number of readings during the same hours of utility use.

The two sets of figures will provide a ''before and after'' comparison of the effectiveness of conservation efforts.