l.By thinking small, a group of South African scientists may have pioneered solar technology that has stumped internet giant Google. 'Plonkable' An engineer at Stellenbosch University's Helio100 project says the team has designed a cost-effective heliostat that harnesses solar power to generate electricity. A heliostat is an energy producing device that uses mirrors or lenses to reflect sunlight. Research engineer Sebastian-James Bode says the South African device is different because it is "plonkable", meaning it can be plonked down, without much construction needed to set it up. The team aims to reduce production cost further to 6 cents per square meter of mirror. Until now, building heliostat plants has been prohibitively expensive. In 2011, Google announced that it halted its own heliostat project after researchers could not design an inexpensive model.