Solar Power

Investing in Solar:

The major arguments for investing in solar go something like this: 1. It’s tried and true. The solar industry has proven the concept with more than 350 commercial solar projects installed across the world and many more residential. 2. The technology is there. Innovations in photovoltaic cell technology are creating more efficient solar cells which require less surface area and they are now 22% efficient. 3.Like other renewable energy sources, the solar industry is growing at a healthy rate. 4. And of course, energy demand is skyrocketing and predicted to keep doing so for the forseeable future, and if there is to be a future it will have to be a green one.

Industry Growth:

Along with the other alternative energy industries, the solar energy industry is marked by incredible growth. Since 2004 the industry has had a double digit annual growth rate. Shipments of solar collectors rose 29% in 2006 to 20.7 million square feet, according to the US Energy Information Administration. Total installed photovoltaic systems generated 6,000 MWp (mega watt peak) at the end of 2006 and was projected to hit 9,000 MWp by the end of 2007. And as of 2006 total installed capacity of solar hot water systems was 104 GW and growing at a rate of 15-20% per year.

The largest slice of the market pie is in Germany, with Japan following. 90% of homes in Israel rely on solar to heat their water and China is the leading manufacturer of solar hot water systems with 80% of the market. Mitigating factors to growth are the rising cost of raw materials like copper, and silicon and a skilled labour shortage.

Industry Incentives:

A program in India called the Indian Solar Loan Program helped establish solar power in 18,000 homes in India. Tunisia, Morocco, Indonesia and Mexico are adopting similar programs. Around the world solar incentive programs are in place, however the solar energy industry is confidently announcing that the solar energy industry is stable enough to break away from incentives and deliver cost competitive energy.

Types of Solar Energy:

Solar energy is used directly as heat to heat homes and other buildings and to heat water. Direct solar energy is collected either passively, without the use of mechanical equipment or actively with the use of a collector to absorb and distribute solar. Solar collectors can be as large as, or many times larger in surface area to the absorber of the heat.

Solar energy is also converted into electric energy through photovoltaic devices or solar power plants. Photovoltaic devices such as solar cells change sunlight directly into electricity. They are often used in remote locations that are not connected to the power grid. PVs are made of silicon alloys. PVs are now about 22% efficient at converting sunlight to electricity.

In solar power plants, solar energy is used to heat a fluid into steam and used to power generators to create electricity. At the end of 2006 there were 15 solar electric generating units producing at least 1 MW in the US in California and Arizona.

Major Advantages and Disadvantages:

Solar energy is intermittent, depending on when the sun is shining, making it both weather and climate dependent. Also, solar panels need to have large surface areas in order to capture and concentrate enough solar energy.

Uses:

In the United States, 90% of solar energy is used residentially for heat and hot water with the remaining 10% used to produce 580 million kWh of electricity.