Riso is the National Laboratory for Sustainable Energy at the Technical University of Denmark - DTU. It contributes to research, development and international exploitation of sustainable energy technologies and strengthens economic development in Denmark.
Riso has done a huge amount of development work and economic analysis of organic photovoltaics (OPV). It has published several papers covering the costs to produce OPV and in this article IDTechEx summarises some of their findings.
Speaking to IDTechEx, Torben Nielson, Innovation and Business Developer, reports that there are four key areas to develop in OPV - efficiency, stability, large scale processing and applications. Riso has invested €530,000 in an OPV development line, with the cost of the equipment broken down as follows:
Source: T.D.Nielsen, etal. Sol.EnergyMater.Sol.Cells (2010), doi:10.1016/j.solmat.2010.04.074
This equipment has a web width of 305mm. Production capacity is 20,000m per year, or 50KW, assuming an 8 hour shift is worked each day and a yield of 95% is achieved. Using this, Riso have made OPV modules to power a torch. The device, pictured below, costs €18 but can come down to €11 in volume.
Source: Riso DTU
The material cost for each part of the module is shown below. It assumes the cost for time is €80/hour.
Source: EnergyEnviron.Sci, 2010, 3,512-525, The Royal Society of Chemistry 2010
Learning curve for OPV development at Riso DTU
Source: T.D.Nielsen, etal. Sol.EnergyMater.Sol.Cells(2010),doi:10.1016/j.solmat.2010.04.074
Overall, the cost breakdown of a module is as follows:
- Staff salaries 16-20%
- Barrier material 20%
- ITO 25-30%
- Active layer contacts 30%
Removing ITO could significantly reduce the cost. Barriers are also a challenge - longer life modules need more expensive barriers. The active layer has significant scope for price reduction because it is made in very small quantities today.
Riso sees cost and efficiency being the defining parameters for market development. The two are related - as efficiency increases the cost per watt falls. However, it is generally acknowledged that for a single cell there is a practical limit of about 11% efficiency and 15% for a tandem cell. Therefore material costs are also very important.
From about 2013 Nielson expects the cost to drop because the chemical market will start scaling materials. They claim that up to 2007, there were about 1000 key patents on OPV. Materials and device structures take up 78% of all patents in the device portfolio.
For more information please see http://www.risoe.dtu.dk/. Hear Riso present at the IDTechEx Printed Electronics USA conference and tradeshow on Dec 1-2 in Santa Clara, USA.