Perovskites for dramatically cheaper PV


While perovskites have been used to produce solar cells, in laboratory settings, since 2009, recent efficiency increases are indicating that it could be used as an organic photovoltaic material of the future.

Research has been taking place on perovskites at a number of labs, including by organic photovoltaic pioneer Michael Grätzel from the Ecole Polytechnique de Lausanne and by Henry Snaith from Oxford University. Snaith is looking to commercialize the technology with the startup Oxford Photovoltaics. MIT’s Technology Review reports that Snaith has raised US$4.4 million in funding to develop the technology.

Efficiencies in solar cells employing perovskites were very low in the early stages of the material’s application, reports MIT, coming in at only 3.5%. However Snaith says that this has doubled twice in recent times, with a series of papers being published on the field around mid 2012.

Perovskite solar cells can be assembled by spreading the pigment onto a glass or foil substrate, with layers of other materials to facilitate the movement of electrons. Previously perovskite solar cells have been unstable, however recent developments have met this challenge by replacing a liquid electrolyte with a solid material. Researchers say that the most efficient perovskite solar cells come in at around 15%.

In the MIT report, researchers say that efficiencies of perovskite cells could reach 20 to 25%.

Pioneering photovoltaic researcher Martin Green, who has in the past spoken out to pv magazine about the prominence of organic photovoltaic research in the face of the prevailing crystalline silicon industry, told MIT Technology Review that the perovskite material could be used in parallel to existing silicon technology in stack cells.

The perovskite material is "very simple and potentially very cheap" says Green, who is from the University of New South Wales. He notes that the efficiency of perovskite solar cells is "rising very dramatically."