SOLAR ENERGY-- IS IT FOR ME?

Any time you have a need for electrical power and conventional hydro is not accessible, you have an application for Solar Energy!

Some of the more common uses are power for a remote cottage, a boat without access to shore power, or an RV when you are "dry camping". Even people who have hydro access but don't want the hassle and expense of burying cable, will take advantage of the benefits of Solar Power.

Photovoltaics is a wonderful energy source, the fuel is free, it is safe, silent and reliable and of course, environmentally friendly! It does however, have its limitations - for example running high demand loads like air conditioners.

What is Energy?

Energy is around us in a variety of forms: gasoline, running water, light, and electricity to name just a few. We often transfer energy from one form to another, for example, when an automobile uses chemical energy from fuel to move. Some types of energy are easy to store (i.e. chemical) and some are easy to move from one place to another (i.e. electricity and light).

Electricity is one from of energy that we have harnessed in the past 100 years. By definition, electricity is the energy available from the movement of electrons within a conducting material. It is analogous to water flowing out of a hose; the electrons are like drops of water. Enough electrons with force behind them can be used to do useful work.

Volts, Amps and Watts

The common units that are used to measure the quantity of electricity are:
Volts: Electrical force or pressure behind the electrons in a circuit. Analogous to water pressure or PSI, it tells us the system voltage (12, 24).

• Amps: The number of electrons flowing past in a second. Like gallons per second in a pipe, it defines the electrical current in a wire.
  
  
• Watts: Total amount of electrical energy, per second.
  

Amp Hours and Watt Hours

In power systems we describe the total amount of energy consumed over a certain period in either amp hours or watt hours. A one amp draw for four hours has used a total of 4 amp hours (AHr) of current. A 100 watt light bulb over 24 hours uses 2400 watt hours (WHr) or 2.4 kilowatt hours (kWHr) of energy. Note: a kilowatt equals 1000 watts, and a kilowatt hour equals 1000 watt hours. Your local hydro unit charges per kilowatt hour used.

AC Versus DC Current

Just to make things interesting, electrical energy is moved from place to place in two ways. Alternating current (AC) is the most common form; utility power arrives to us as high voltage AC current. Alternating current is like water sloshing back and forth in a bath, the same electrons doing the work in one spot. Solar panels and batteries produce direct current (DC), which is easier to store. DC current is usually used at lower voltages, i.e. 12 or 24VDC.

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