Solar power

Solar power is a form of energy that makes use of the world’s largest energy source: the sun. More than 99% of the world’s available renewable energy is in one way or the other related to solar energy. The sun provides us with 174 petawatts (174,000 terawatts) of energy, of which half (89 petawatts) reaches the Earth surface. Since humanity consumes ‘only’ an estimated 15 Terawatts (2005 figure) of power, we only need to convert a tiny fraction of this free solar energy (~0.00016%) in order to fulfill the energy needs of the global population. Due to increasing environmental and climate awareness, the use of solar power has been growing explosively the past few years. Solar power is now the fastest growing form of energy, far outpacing other renewable energy sources like wind and water. The advantages of solar power are many; it is renewable, silent, emission-free and consistently available. Solar power’s main disavantage is its price; harnessing the power of the sun is still relatively expensive. It is however expected that technological and economical developments will within 10 years put the price of solar power on par with traditional energy sources.

Types of solar power

Throughout the years, humanity has learned to make good use of both the suns light and heat. The following techniques each take a unique approach towards harvesting solar energy. The specific purpose, advantages and disadvantages of each respective technique allow solar power to be broadly applicable:

Solar power in the United States

Solar power is the most abundantly available form of renewable energy in the United States. However, compared to European countries like Germany and Spain, the market remains vastly underdeveloped. Considering the US is the very birthplace of solar photovoltaics, this is a wasted opportunity in the least. Things are however changing, due to increasing environmental and geopolitical awareness. Last year, total US solar power capacity grew to 8,775 megawatts, a growth of 17%. Note that these figures include solar thermal appliances like pool and space heating. Looking at solar photovoltaics only we see an estimated increase of 342 MW. Compared to Spain (2,460 MW) and Germany (1,860 MW) this figure leaves much to desire. Things are however bound to improve, in large part due to the eight-year extension of the 30% tax credit on solar photovoltaic installations. Finally, the Obama administrations positive stance towards solar power is likely to further propel solar to the center stage of American energy policy.

US growth forecast of solar power 2009-2016
US solar growth forecast for 2009-2016. Image credit: navigant consulting, inc.

Since utilities now view solar as an opportunity instead of a threat, it is expected that solar energy will reach full grid parity in all states by the year 2015 / 2016. By this time, the whole solar industry is predicted to employ no less than 400,000 “green collar” people. Despite the economic setback of 2008/2009, the future of solar is looking sunny indeed.

Why solar power?

The advantages of solar are numerous:

Video: the power of the sun

This video (2 minutes 45 seconds) demonstrates the power of the sun by melting a brick using a mere piece of plastic!