THE WIND POWER BOOK

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Apparently many people would like to install a $1,000 wind machine and "switch off" good old Edison. This is a fantasy. It might be reasonable to use the wind to power your house if old Edison is a $30,000 powerline away from your new country home, but most end uses for wind power will be somewhat less extravagant.

A successful windpower system begins with a good understanding of the intended application. For example, should you decide that water pumping is the planned use, you must determine how high the water must be lifted and how fast the water must flow to suit your needs. The force of the wind flowing through the blades of a windmill acts on a water pump to lift water. The weight of the water being lifted and the speed at which the water flows determine the power that must be delivered to the pump system. A deeper well means a heavier load of water ...speeding up the flow means more water to be lifted per second. They both mean more power required to do the job, or a larger load.

This concept of load is crucial to the understanding of wind power. Imagine that instead of using a windmill you are tugging on a rope to lift a bucket of water from the well. This lifting creates a load on your body. Your metabolic processes must convert stored chemical energy to mechanical energy. The rate at which your body expends this mechanical energy is the power you are producing. The weight (in pounds) of the bucket and the rate (in feet per second) at which you are lifting it combine to define the power (in foot-pounds per second) produced. How long you continue to produce that power determines the total amount of mechanical energy you have produced.

The kind of application you have in mind pretty clearly defines the load that you'll place on your windpower system. Knowing something about that load will allow you to plan an energy budget. "What the #$°/a&," you ask, "is an energy budget?" Let's explain that with an analogy.

When you collect your paycheck, you have a fixed amount of money to spend. You probably have a budget that allocates portions of your money to each of the several bills you need to pay. With any luck, something is left over for savings, a few beers, or whatever else you fancy. Energy should be managed the same way, and if you live with wind power for very long, you'll soon set up an energy budget.

Setting up an energy budget involves estimating, calculating, or actually measuring the energy you need for the specific tasks you have in mind. If you plan to run some electric lights, you must estimate how many, how long, and at what wattage. If you plan to run a radio for three hours each evening, you'll have to add that amount of electrical energy to your budget. If you want to pump water, you should start with estimates of how much water you need per day and calculate how much energy is required to pump that much water from your well into the storage tank.

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