Solar panels offer a clean source of alternative energy – but ironically, the solar industry has a significant carbon footprint due to its reliance on coal and natural gas to manufacture photovoltaics. Fortunately, a new study by Michael Dale from the Stanford Global Climate & Energy Project shows that the PV industry is set to pay off its energy debt as early as 2015. Published in the latest edition of the journal Environmental Science and Technology, the study details the declining energy inputs necessary to create photovoltaic panels and advances in technology that have aided in the development of the PV market around the world.
In past years it took an enormous amount of energy to fabricate solar panels – and more often than not it was derived from coal-fired power plants. The first step to produce the silicon that comprises most panels is to melt silica rock at 3,000 degrees Fahrenheit. Newer technologies that require less energy input have helped to drive down the overall footprint of the PV industry. Thinner silicon wafers can now be used to make cells, and there have been improvements in thin-film printed cells that take advantage of other materials such as zinc, copper, tin, and carbon.
To become net positive, PV panels will have to produce more energy than the amount it takes to make them. From 2000 until now the industry ran at a deficit, but Dale expects advances in technology to enable the PV industry to pay back its debts by 2015. If the growth of the market continues, ten percent of the world’s electricity could soon come from PV systems. For this to happen, the industry must continue to find ways to reduce energy input while minimizing the over cost of solar arrays and components. Energy payback could also be sped up by installing arrays in areas that have more consistent sunshine and utilizing energy conservation strategies.
Via Clean Technica