For some of you it may be instructional to start at a basic level in understanding how electricity works in everyday life.

Watts

You might have noticed that the power consumption of electrical devices is measured in watts. Most people are fairly familiar with the term watt, but most don’t know what it describes. A watt is the power produced by current (amps) flowing through a wire multiplied by the pressure (voltage) at which it flows.

Volts

Like water pressure in a pipe, voltage is the pressure of electricity flowing through the wire.

Amps

This is the amount of electricity flowing through the wire.

Power Rates

We are most familiar with the term KWH (or Kilowatt-Hour) as it appears on our monthly power bills. This is the rate of power flowing through a wire. As an example, if a 100 watt light bulb is turned on for ten hours the power rate would be 100 x 10 = 1,000 watt-hours or 1 Kilowatt hour (kilo means 1000)

Direct Current (DC)

We will be discussing both Direct Current (DC) power and Alternating Current (AC) in the planning of your renewable energy system. AC current is what you presently use in your home.

The most important difference between AC and DC power is that DC current can be stored in a battery while AC power cannot.

In the renewable energy system that you are designing to run your home, DC power produced by your wind generator or your solar panel will be converted to AC power by using an inverter. In this way you can still use many of the same AC appliances that you currently depend on.

Common DC voltages are 12, 24 and 48. The advantages of DC appliances are many, but most important is that DC motors are more efficient than AC motors. There are many applications for DC power and the benefit is that we can use this form of energy in our off grid home, while in your present tied-to-the-grid home you cannot.

AC Current

Alternating current is called this way because the current changes direction constantly. AC is the most common form of electricity usage today mostly because it is easier to work with than common DC current.