This module is part of a program whose long-term aim is to manufacture polymer solar modules, also called organic photovoltaic (OPV) modules, on large printing presses, greatly reducing the cost of solar electricity. Standard solar cells are about 200 micrometres thick and are made from silicon that is won from its oxide at high temperatures using charcoal as the reductant. In contrast, the active polymers in this module are made at low temperatures and deposited from solution in very thin layers. This leads to energy payback times of 3 to 4 months rather than 3 to 4 years.
The aim of this part of the program is to test a range of techniques and parameters in order to create structures consisting of smooth, uniform, durable layers of polymers using methods that could be scaled up to roll-to-roll production on printing presses. This complements the research team's other aim, to improve the efficiency of its solar technology by making and testing a variety of small solar cells that incorporate novel polymers.
The techniques used in making this module draw on experience in making polymer banknotes, a major Australian innovation whose development was led by Dr David Solomon. The banknote printing process has been commercialised, and banknotes marketed worldwide, by Securency, a partner in the polymer solar research.
Another partner in the project is BlueScope Steel, which makes millions of square metres of roofing steel each year. Incorporating OPVs into roofs would benefit the company, building owners and the environment. The availability of building-integrated photovoltaics (BIPV) is growing, with a range of solar technologies being incorporated into building elements such as roofs and windows, and OPVs could accelerate this trend by reducing BIPV costs.
Polymer photovoltaics have the following advantages over other solar modules: they are much lighter in weight; they can operate in low light conditions; they can be used on roofs that face any direction; their efficiency does not fall much over time; and they are less visually obtrusive. The disadvantages at present are their lower efficiency and shorter lifetime, and research groups around the world are working to address these problems.
The module is also interesting because it incorporates two ideas for which chemists have received Nobel Prizes in recent years. These are the discovery of buckminsterfullerene by Kroto, Curl and Smalley in 1985, which won them the 1996 prize, and the development of conducting polymers by Alan Heeger, Alan MacDiarmid, and Hideki Shirakawa in the 1970s, which won them the 2000 prize. It also incorporates a semiconducting polymer; although these were known before the work of Heeger et al, this research led to better understanding of their electrical properties and hence helped later researchers design semiconductors for a range of applications..
Debbie Rudder, Curator, 2010
M Jacoby, 'The power of plastic', Chemical & Engineering News, 23 August 2010, pp12-16.