How Home Solar Power Systems Work

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.

Electricity is created by utilizing sun light energy. The technology that does this is known as the photovoltaic (PV) cell. A cell is made from a silicon compound that throws an electron loose of the atom whenever sunlight of a certain frequency strikes the cell. When many cells are linked together in series, this forms an electric current.

Many PV cells connected together in series is referred to as a solar module. When many solar cells are connected together than are known as a solar panel.

Solar panels are the devices that you may have seen on the roofs of houses in your neighborhood. They can be placed elsewhere, but the roof is often the most sensible place as it is likely to get exposed to direct sunlight and the panels can't be damaged or vandalized as easily or take up room in the yard.

The solar panels create direct current (DC) electricity. This is often pushed through a power inverter. The inverter converts DC to alternating current (AC). AC is used in the home to power most 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.

An example of how this works is during midday. In theory this is the best time for your solar panels to create electricity. As you may be out or at work this will also be the time when you use little or no electricity. So the utility meter might go backwards indicating that you are generating electricity for the utility 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.

Typical back up systems are a fuel driven power generator or some type of renewable system, like a wind or water power system. An off grid solar system also has to store DC in batteries so that it can be used at night when there is no Sun. This is an extra responsibility.

Most people go for an on grid system with net metering as this is less responsibility and can stack up economically. With more experience they may go more off grid. Of course this is more responsibility and work but the potential to save money is greater.