This Sunpower is the Cypress-owned Photovoltaics company
not to be confused with sunpower.com, a stirling/cryocooler R&D lab and boutique lab equipment vendor. Their webpage is sunpowercorp.com
http://sanjose.bizjournals.com/sanjose/stories/2005/08/22/daily53.htmlLatest R&D: they found a tweak to control surface polarization on high efficiency solar cells that will increase output if properly controlled. They are being tight-lipped as to by how much, AFAICT.
http://www.eet.com/news/design/technology/showArticle.jhtml?articleID=169500342As far as can be surmised from their webpage, they concentrate on tweaking traditional flat-plate collector cells, not concentrated PV. They do boast a 20%+ efficiency though, and infer that their cells have a better daily production curve, though they aren't clear in promo materials as to whether this is due to optics tricks to eliminate angle of incidence problems, or better waste heat flux, or something else (there are some technical papers on the website if you aren't adled by lack of sleep like me.) Main product seems to be 200W(p) residential and 220W(p) panels, with the residential panels "looking better."