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Your Consumption

1. Estimate Your Annual Electricity Demand

For this estimate, you will need to know three things:

a) The selection of appliances/electrical loads you want to run with the electricity generated by your small-scale wind energy system.  Consider the following four categories of appliances/electrical loads:

• Large intermittent loads - Electric versions of intermittent-load appliances such as water heaters, clothes dryers, stoves, heaters, kettles, toasters, hair dryers, curling irons, etc. can be run from a renewable electricity system, but it is almost always cheaper to use propane/butane versions of these heating appliances and use wood stoves, where appropriate.  Heat is generally cheaper to produce than electricity, since it is a lower grade of energy.  Vacuum cleaners would also fall under large intermittent loads.
• Medium intermittent loads - Appliances such as refrigerators and freezers draw a large amount of electricity intermittently, and the supply must be reliable.
• Small intermittent loads - Televisions, stereos, and other smaller loads are not run constantly and can be used according to electricity available (especially on an off-grid system).
• Small constant loads - Lighting, on the other hand, does not require that much power, and the draw is fairly consistent.

If you plan to use wind energy to run systems on a farm, remember to distinguish between equipment required to operate the farm, and the energy requirements of the home. Power needs for farming equipment vary widely, especially when it comes to livestock watering, and should be accounted for separately.

b) The length of time, in hours, each of your appliances will run.  Consider any future increases or decreases in your home/office/farm energy consumption due to number of people, nature of living/business, etc.

c) How much power each appliance draws. You may find power specifications inscribed on a plate or sticker on the back of your appliances.  You can also refer to Electricity Demand Data on this site.

See the sample worksheet below to help you calculate your annual energy use.

Sample Annual Energy Consumption Worksheet

For reference, a typical home uses approximately 9,400 kilowatt-hours (kWh) of electricity per year (about 780 kWh per month).