Light Collector in Nanoformat

Solar cells based on organic dyestuffs promise lower costs.
Photovoltaics are still unable to compete with conventional energy sources. Solar cells, on which isolated molecules generate energy on cost-effective thermoplastic foil, could considerably reduce production costs. The technology should soon be on the market.

In order to make solar energy cheaper, companies are eagerly researching new photovoltaic (PV) concepts. The latest achievement is a solar cell, with which dye molecules convert sunlight into energy instead of solid silicone or thin-film absorbers. Extensive particles are evaporated onto a thermoplastic foil in a vacuum with slightly increased temperatures. Because only a small quantity of material and energy are required, the manufacturing costs are reduced. At the same time, the procedure makes a very good level of efficiency possible for organic photovoltaics: Laboratory cells achieve 7.7 percent efficiency, making them on a par with commercial photovoltaic cells made of amorphous silicone.

The technology was developed by Dresden-based company Heliatek, a new company from the TU Dresden and the University of Ulm. This year, the company wants to start a small production line for its technology with four to eight Megawatts (MW) of annual capacity. The company’s director, Andreas Rückemann believes the first products will be positioned on the market by the beginning of 2012 at the latest. By 2015, the manufacturing capacity should be up to 700 MW. Heliatek’s enthusiasm to expand is no accident: Renowned investors, among them BASF, Bosch und RWE, are backing the newcomer, investing 18 million Euros in the company. “This means financing for the initial expansion stage is guaranteed,” says Rückemann.

Heliatek’s innovation could be an important step towards the competitive ability of photovoltaics. The specialists want to reduce the manufacturing costs to 0.40 cents per watt by 2015, while increasing the efficiency of the modules to at least ten percent. This would make the technology more cost-effective and efficient than, for example, the standard thin-film modules made of amorphous silicone. These are primarily used in building integration today, due to their low weight and successful properties in weak light.