Since January 1993, ‘Progress in Photovoltaics’ has published six monthly listings of the highest confirmed efficiencies for a range of photovoltaic cell and module technologies.1,2,3 By providing guidelines for the inclusion of results into these tables, this not only provides an authoritative summary of the current state of the art but also encourages researchers to seek independent confirmation of results and to report results on a standardised basis. In the present article, new results since June 2006 are briefly reviewed.
The most important criterion for inclusion of results into the tables is that they must have been measured by a recognised test centre listed in an earlier issue.2 A distinction is made among three different eligible areas: total area, aperture area and designated illumination area.1 ‘Active area’ efficiencies are not included. There are also
certain minimum values of the area sought for the different device types (above 0
05 cm2 for a concentrator cell,1 cm2 for a 1-sun cell and 800 cm2 for a module).1
Results are reported for cells and modules made from different semiconductors and for sub-categories within each semiconductor grouping (e.g. crystalline, polycrystalline and thin-film).