If you look at your figures and reduce your use of electricity by even one kilowatt-hour, you'll save two pounds (about 1 kg) carbon dioxide from being pumped into the atmosphere. And it's carbon dioxide that contributes most to global warming.

2torial #0822: Learn2 Calculate Utility Costs (Continued) Estimate hourly usage per month   Estimating is the trickiest part of this procedure, so sit back now and consider how often you use the items on the list. Some folks are stumped when they try to remember how many hours they used the stove last month. But realize this: you don't need an exact figure down to minutes and seconds for each appliance--you need an estimate. Below are some tips to help you get a ballpark figure for each appliance. When in doubt, estimate a little more rather than less, and you'll have fewer surprises on next month's bill. Look at each appliance and recall at what times in a day you switch it on (or it turns itself on). And how long do you have that device switched on? Remember that you may use some appliances more certain days than others. If you work outside of the home, for example, you may use your stove very little during the workweek, but cook a lot during your leisure time. In a situation like this, total the number of hours you typically use the appliance for the week, and divide that number by seven--this will produce the average daily use. Multiply that figure by thirty, and you'll have the number of hours you use the item over a month. In the second column of your final report (next to the name of the appliance), write down the number of hours you use it per month. (If you're really stumped but you'd really like to do this exercise, try jotting down how often and for how long you use of a certain appliance. Ask yourself, "How often do I turn on that air conditioner, or that room heater?" Do this for a week and you'll have an idea for the appliances that you record.)   There may appear on your list items you use less during certain months than others: a furnace or an air-conditioner, for example. The amounts can vary enormously depending on your lifestyle. Other variables to consider are: Do you work at home? Is your house empty while you're at work? Do you have a spouse or children (or both) at home most of the day? Do you have children who are at home during summer and winter vacations? Do you have an elderly relative who stays with you?   Excepting the situation where your home is empty while you're at work, all of the above scenarios will translate into higher energy consumption and therefore, higher utility bills. If you've recently moved to a new home, it may take a few months before you can really estimate what your power usage will be. And that figure may change as new members of the household arrive and other members leave, i.e. children who are born or children who grow up and move out. In a situation like this, estimate how much you use it month by month over the course of a year. Once you estimate yearly usage, divide that number by twelve to arrive at the average number of hours you use the item over a month. This is the figure you'll use in the following steps. Step 3