Scientists make cheap and less toxic solar cells

Researchers at the University of Liverpool have devised a way to replace toxic chemicals used in the production of a specific type of solar cells with a compound that is not only safer, but also cheaper.

The substance that is currently being used, cadmium chloride, is currently used in photovoltaic cells based on cadmium telluride: solar panels with these solar cells achieve efficiencies of up to more than 15 percent. Since cadmium chloride is a highly toxic substance, workers must adhere to strict safety rules during the production of those solar cells. In addition, discarded solar panels must be treated with care when they are processed into waste. According to the researchers, the new method using magnesium chloride in the production process is much safer. Magnesium chloride is said to be extracted from seawater, among other things, and is already used in the production of tofu and bath salts. The substance is not only safer, but also a lot cheaper than cadmium chloride and could completely replace its use.

Magnesium chloride could simply be applied with a spray gun in an environment that does not need to be squeaky clean. Moreover, the cost per gram of magnesium chloride, with an average price of one tenth of a dollar cent, would be much lower than the thirty cents that cadmium chloride costs per gram. However, the effect that the use of magnesium chloride will have on the final price of solar panels will not be too high, since the cost share of cadmium chloride in solar panels is small. In addition, the majority of solar panels currently in circulation use silicon-based photovoltaic cells. The telluride cells to which this method has been applied still represent a small proportion of the solar cells produced.

Jon Major, the physicist who led the project, says that if renewable energy is serious about competing with fossil fuels, its costs must be drastically reduced. “Good progress has already been made, but if the techniques we researched are applied, it could be good that costs will be reduced even further,” says Major.