Solar power is our free source of energy

About thirty years ago, Americans were importing only 33 percent of fossil fuels for their energy need. This has subsequently increase to about 50% with the prediction that in a few years time, Americans will be importing more than 60% of fossil fuels for their energy need. Even though the sun shines on the earth about 35,000 times more power than we use daily, only about less than 1 percent or less than 0.2 percent of our energy comes from solar power. As long as the sun continues to shine (it is expected to continue to shine for billions of years), this energy is renewable because no matter how much we use it, the amount of energy we receive from the sun will remain the same. Currently, 39% of energy needs in the US comes from oil with 23 percent from natural gas and 24 percent from coal. Nuclear energy make up about 7 percent with 6 percent coming from hydropower dams. Only about 1 percent currently comes from renewable energy such as wind power and solar power.

The sun is a massive star in the solar system which pretty much supports all life on Earth. When the sun is shining on Earth, it generates about 1 Kilowatt per square meter. The natural process by which sunlight is converted to energy and stored as food is call photosynthesis. Even petroleum is derived from stored energy from photosynthesis eons ago. Absent of any major catastrophic event in our galaxy, the sun is expected to shine for billions of years which is many lifetimes of humans.

Therefore, in effect, it provides an infinite source of energy if humans learn how to tap the solar power provided by the sun. At 1 Kilowatt per square meter, if we can convert at a 100% efficiency, it can power sixteen 60 watt light bulbs. Currently, the most efficient solar panel can convert at about 45% efficiency though most commercial panels are between 9-15% efficiency. Unfortunately, the sun does not shine equally all the time. At night, the sun does not shine in most places and solar power is non-existent unless it is earlier stored. Also, the sun shines mostly and strongest at the equator which is why countries in those areas like Mexico and the Middle East can benefit most from solar power.

It takes about 13,200 gigawatts to power the entire US. A solar cell at 15% efficiency can produce about 70 milliwatts per square inch. To get 13,200 gigawatts, we would need 46,972 square miles of solar cells. Therefore, a land of 200 square miles by 200 square miles of solar cell would be able to supply the entire US with enough power when the sun is shining. At about $4 per peak watt, it would have cost about 52.8 trillion dollars to power the entire US with a life span of about 10-15 years.

Even if solar power is free, the price of building out solar farms is not cheap. At today's efficiency, solar cells is still unable to match the price of coal-generated electricy. However, as efficiency increases, solar power will become much more cost competitive. Meanwhile, tax incentives are needed to sustain the market. With the price of oil shooting through the roof and its limited supply, it only make sense to have government support innovation in the market place to provide the economics to drive down the cost of solar power eventually.

Solar power is essentially free as long as the sun shining on Earth continue to exist. Unless something catastrophic happens to our sun, it will definitely outlast fossil fuel. There are primarly 3 types of technology that uses solar power: photovoltaic cells, concentrating solar power technologies and low-temperature solar converters.