Business Green: A breakthrough in solar cell design that could dramatically improve the efficiency of the technology to more than 60 per cent has US researchers hot under the collar. A team from the University of Texas claims to have found a way to tap the energy wasted by solar cells through so-called “hot electrons”. Led by professor of chemistry Xiaoyang Zhu, the Austin team reported its findings in last week’s edition of Science. The researchers say they have discovered a method to utilise …