Solar and Wind Power

There are a few ways to use the Sun’s energy to create home solar power systems. They can be categorized as passive and direct systems. Passive systems have been use for thousands of years and the inspiration behind such systems was probably the fact that our ancestors felt hot in the Sun. From this point they realized that the heat from the Sun can make water hot, cook food, dry clay bricks and countless other applications. Today there are systems that can passively heat the home living areas and the water used in the home. This article will not cover these topics but focus on the direct use of the Sun to create electricity for use in the home.

In terms of the use of solar energy, creating electricity from sunlight is a relatively new innovation. The technology needed to create electricity from sunlight was first developed to a commercially viable standard in the 1950’s. It is known as the photovoltaic (PV) cell. A PV cell is made of a silicon compound that reacts when photons from sunlight strike it. This reaction causes an electron from the silicon atom to be thrown loose. When a number of PV cells are linked together in a serial configuration, the electrons flow to a positive charge creating an electrical current.

A number of PV cells in a serial configuration is known as a solar module. When numerous solar modules are linked together in either a parallel or serial configuration they are known as a solar panel.

No doubt you have seen a solar panel on one or more roofs of homes in your area. This is where they are normally installed but they can go anywhere provided they get access to direct sunlight.

The solar panel creates direct current electricity (DC). By passing it through a power inverter it can be transformed to alternating current (AC). AC is used in most homes to power everyday appliances.

AC is distributed to the various wall sockets, lights and other power points in your home by an electrical service panel. A utility meter will take account of the electricity that is consumed if you are connected to the utility grid.

For example, a solar panel works best when the sun is at it peak or midday. Most electricity will be generated at this time and the utility meter may well go backwards. This indicates that you are generating more electricity than you are actually using and effectively creating electricity for your power company.

A home solar power system can be either on or off the grid. On the grid is sometimes referred to as a net metering system or grid tied.Various states have laws that require utility companies to offer net metering programs to people using solar panels. This effectively means that they are fairly compensated for the electricity that they create rather than having to sell it at a wholesale rate.

A true off grid system means you are not connected to a reliable power supply so you have the responsibility of creating your own energy. The primary source can be solar panels but there should always be a back up system in case you use more energy than you expected or the Sun doesn’t shine as much.

Gasoline powered generators are often used as a back up system as they are fairly reliable, however some people that have the space may opt for another form of renewable resource, like a water or wind driven power system. Another responsibility of an off grid system is keeping a battery bank to store DC from the solar panels for use at night times.

Most people start with a grid tied system as it is easier to use and there is less responsibility. As you gain more experience you may think about going off the grid. This form of home solar power system will save you money on monthly utility bills but more work to run and maintain.