Introduction to Inorganic Thin Film Solar Cells

Solar energy represents the largest energy input into the terrestrial system. Although photovoltaics is not the sole answer to the myriad of energy challenges offered by the clean and economical use of sun spectrum, this renewable energy option can make an important contribution to the economy of each country. Despite its relatively low power density, the solar electricity market is booming. By the end of 2007, the cumulative installed capacity of solar photovoltaic (PV) systems around the world had reached more than 9,200 MW. This compares with a figure of 1,200 MW at the end of 2000. Installations of PV cells and modules around the world have been growing at an average annual rate of more than 35% since 1998. The EPIA/Greenpeace Advanced Scenario [1] shows that by the year 2030, PV systems could be generating approximately 2,600 TWh of electricity around the world to satisfy the electricity needs of almost 14% of the world’s population Photovoltaics stumbling block has always been its cost but it has held the promise of providing clean electricity and competitive rates. The cost is declined by a factor of nearly 150-160 times since the invention in 1954 of the modern solar cell based on crystalline silicon technology. More then 90% of the current production uses 1st generation PV wafer based cSi (1st G PV) a technology with the ability to continue to reduce its cost at its historic rate. The direct production costs for crystalline silicon modules are expected to be around 1 €/Wp in 2013, below 0.75 €/Wp in 2020 and lower in the long term as indicated in table 1 [5].