First Solar has broken down the barriers to producing high performance thin film solar modules in volume, making solar electricity an affordable alternative to fossil fuel-generated electricity.
Multiple years of high volume production and power plant operating experience demonstrate First Solar's efficiencies, high energy yields, low production costs and excellent system performance ratios. Today, First Solar’s module production facilities are achieving high levels of module efficiency and factory throughput that have required many years of production experience and continuous improvement to attain. First Solar's 'Copy Smart' plant replication process has enabled First Solar to repeatedly and predictably expand manufacturing operations worldwide, allowing large scale expansion of module production.
This success is, to a significant extent, attributable to the unique physical properties of the semiconductor material which make it ideal for converting solar energy into useful electricity.
- CdTe (Cadmium Telluride) is a direct bandgap semiconductor, which enables it to convert solar energy into electricity more efficiently (i.e., more watts per kg of material) than the indirect bandgap semiconductor materials used historically.
The energy bandgap of the semiconductor material, at 1.45ev, enables it to convert more energy from the solar spectrum than the lower energy bandgap materials (1.20ev) used historically. As a result, it is capable of converting solar energy into electricity at an efficiency level comparable to historical technologies, but uses only about 1-2% of the semiconductor material required by traditional PV technologies.
- CdTe will generally produce more electricity under real world conditions than solar modules with comparable power ratings.
Solar cells become less efficient at converting solar energy into electricity as their cell temperatures increase. However, the efficiency of this semiconductor material is less susceptible to cell temperature increases than traditional semiconductors, enabling First Solar thin film modules to generate relatively more electricity under high ambient (and therefore high cell) temperatures. The semiconductor material also converts low and diffuse light to electricity more efficiently than conventional cells under cloudy weather and dawn and dusk conditions. As a result, First Solar thin film modules will generally produce more electricity under real world conditions than conventional solar modules with similar power ratings.
- CdTe permits simple device structures and manufacturing processes, leading to low cost production.
High performance modules are achieved with single junction, polycrystalline devices. Automated high throughput production processes have been employed successfully, without the need for expensive clean rooms or other specialty equipment.
- Abundant semiconductor materials to support high volume production and demand.
This stable, inert semiconductor is made from cadmium and tellurium. Both elements are byproducts of the mining and production of base metals such as zinc and copper. These materials are present in abundant quantities to support multi-GWs of annual production.
These attributes have led the National Renewable Energy Laboratory in Golden, Colorado to recognize CdTe's potential for achieving the lowest production costs among current thin film technologies. (Photon International, November 2004, page 50). As a result, future module costs well below $1.00/Wp have been predicted by NREL and others.
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 First Solar FS Series 2 PV Module |
