http://www.nzherald.co.nz/business/news/article.cfm?c_id=3&objectid=11504119
By thinking small, a group of South African scientists may have pioneered solar technology that has stumped Internet giant Google, AP reports in the NZHerald.
The Helio100 project at Stellenbosch University harnesses concentrated solar power to generate electricity, and it does so cheaper than other attempts, according to its creators.
A heliostat uses mirrors or lenses to reflect sunlight, concentrating the solar energy onto a receiver tower, which then uses centuries-old steam power to generate electricity, said Sebastian-James Bode, a 28-year-old research engineer working on the South African project.
Until now, building heliostat plants has been prohibitively expensive. In 2011, Google said that it stopped its own heliostat project after researchers could not design an inexpensive model.
“At this point, other institutions are better positioned than Google to take this research to the next level,” Google said back then in a statement, making its findings freely available in a 10-page report, AP said.
For many in the renewable energy sector, concentrating solar power technology offers a solution to the perennial problem of renewables: what happens when the wind isn’t blowing and the sun is hidden or it’s not shining at night, Mail&Guardian reports.
Helio100 is being funded by South Africa’s Technology Innovation Agency, created by parliament to develop and bring to market research projects by private and public entities.
The Helio100 team began their work in April 2014, coming up with a much smaller heliostat than Google’s, made of six triangular mirrors that don’t need a concrete foundation, according to NZHerald. They also devised wireless, smart positioning technology that ensures the beam of light is always on target.
This compact construction, makes it “plonkable,” said Bode, meaning it can be plonked down without needing two people to set it up.
The device was designed with South Africa in mind — electricity blackouts are common there, but it also has one of the highest rates of direct normal irradiation, a measure of sunniness, according to Mail&Guardian.
Concentrated solar power could become a competitive source of power in peak and intermediate loads by 2020, and of base-load power by 2025-2030, according to the International Energy Agency. By 2050, with appropriate support, it could provide 11.3 percent of global electricity, Mail&Guardian reports
The challenge is harnessing and storing that solar energy.
The next step will be to produce the heliostat on an industrial scale, and international investors are already interested, AP reports. The goal is large-scale production to generate electricity or heat. It can also be used with other renewable energy sources like rooftop solar panels and wind.
“The solution for South Africa, and indeed the world’s energy problems, is not a single technology that will do everything,” Bode said.
Stellenbosch University‘s pilot concentrated solar power facility will demonstrate the new solar collector system with a launch date at the end of September.
The project is located at Mariendahl, an experimental farm belonging to the university. The Helio100 technology is designed for concentrated solar power plants as small as 100 kilowatts – enough to power about 30 South African households, according to the university.
In 2009, Thomas Fluri – a Stellenbosch University researcher who has since become head of the solar thermal power plants at the Fraunhofer Institute in Germany – identified the potential for concentrated solar power in South Africa, Mail&Guardian reports.
Fluri wrote in an Energy Policy journal article that concentrated solar power had the potential to produce more electricity than South African power utility Eskom’s fleet of 20 power stations.
“Concentrating solar power is the new kid on the block,” said Helio100 project leader Paul Gauché, “which means it is still more expensive.” But Helio100, he said, is “showing signs of being the cheapest heliostat system in the world.”
