Your local utility company reads your electricity meter every month to determine how much electricity you used between the previous and current billing periods. The electricity your devices, appliances, and lights use is measured in watts, and your total energy consumption is measured in kilowatt hours (kWh). One kWh is equivalent to running a 100 watt light bulb for 10 hours, or using 1000 watts over the course of an hour. This energy consumption is totalled up between all of the electrical devices and appliances in your home and that total is represented by numbers or dials on your electric meter. If you want to get a sense of how much electricity your home consumes over a given day or week, you can read the meter to find out this information yourself. Digital meters display the number of kilowatt hours consumed and are easy to read, but analog meters with gears and dials may seem a bit confusing at first. Analog meters typically have between four and six dials that tell you how many kWh you’ve used. Some are designed like the odometer of a car and are simple to read but others have circular dials with a needle point to or in between numbers. These dials also alternate between clockwise and counterclockwise directions.
The first step to reading a meter is to make sure you are looking directly at the needle you wish to read. Looking at it from an angle may skew the reading. Reading the dials from left to right, you read each number that the needle has passed. The needle always travels along the numbers in ascending order, regardless of whether it’s clockwise or counterclockwise. If the needle looks like it’s directly over a number, check the next dial to the right. If the next dial has passed 0, read the number the needle is over. If it has not passed 0, read the number before the one it is over. Below is an example of a 5-dial analog meter. We will read this meter and give an example of a week’s worth of energy use.
Using the method discussed above, we clearly see the first dial is 2, the most recent passed number. The second dial is over the 6, but the third dial is just before the 9, so the second dial is 5. The third dial is 8, the fourth is 6, and the fifth is 6. As you can see, each dial rotates in the opposite direction of the previous dial.The electric meter above reads 25866 kWh. Let’s say this is your actual meter reading. On the same day the following week, the meter reads 26223. By taking 26223 and subtracting last week’s reading, 25866, from it, you get 375. That means your home has consumed 357 kilowatt hours worth of electricity since reading your meter the previous week. If you want to get an average weekly consumption over the course of a month, repeat the process for the next three weeks, add the differences together and divide them by 4, the number of weeks.
Your energy consumption is not going to be the same each week. Weeks that are hotter or colder will have higher differences because of the added use of climate control in your home. You can use the meter to track how much electricity various appliances consume in your home as well. Check the lowest value dial (which would be at the far right or possibly a thin rotating disc at the bottom) over the course of 15 seconds. Multiply that number by 4 to get the energy consumption per minute. Then, you can shut off a circuit to a part of your home like your living room, then check the meter again. The last dial or disc will be spinning more slowly and you can see how much electricity that part of your home is consuming. It may be easier to invest in an ammeter, however.