Posts from — June 2009

Photovoltaic cells are tiny black squares placed on an array known as a solar panel to produce energy from the sun. They are also becoming smaller in size and this is what's making them cheaper to produce despite the fact that their efficiency is increasing. The price of solar power energy is tagged at pr watt per hour at this time of writing. Just 17 years ago, the expense for getting the same performance was about, double what it is today.

Solar powered electricity generation is one of the best things that have happened to the environment. This is an alternative form of energy production that does not emit any hazardous material into the environment and uses something that is naturally available as its source. Today, solar collection cells have become very popular additions to the rooftops of people's houses. Whether it is for heating your home or heating water or producing electricity for the home, you will find that these devices are quite simple to use. For heating water, water is first allowed to pass through the photovoltaic cells.

Photovoltaic cells of today enable you to gather heat from the sun and store it even if the sky is full of clouds or if there is a storm brewing. It manages this by designing the solar cells to absorb and store more energy on bright sunlit days so that this can be used when the weather is not favorable.

There is actually another solar power system available for use called the PV System. A connection is made of the PV system to the nearest grid of electricity and when a particular home produces more energy using the solar cell, this excess energy is sent off to the grid so now the grid will use this energy for electricity production. The best benefits of using PV systems are that you are getting solar power inexpensively, you are using a source of energy that is in accordance with the environment and you are freeing up the pressure on the grid. Town planning in some areas today includes setting up central solar accumulation arrays so that this energy could be available for the entire town.

The indication of the practicability and the economic sense behind solar power generation is clearly understood from the entry of several corporate entities into this area. Google has already installed a 1.6 MW solar power generation plant on the roof of its headquarters while Wal-Mart will soon outdo this by installing a 100 MW solar power system of its own.

The popularity of solar power generation is being further fostered by countries like Germany, Switzerland, Japan and of course the US by subsidizing individuals or companies who are installing these systems and also providing additional tax deductions to them. This kind of interest will only help make it more and more popular and ultimately - affordable!

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.