Switzerland’s solar sunflower

Airlight Energy and IBM Zurich will release the high-concentration photovoltaic thermal (HCPVT) system known as the solar sunflower for commercial production in 2017. — Photo courtesy of IBM Zurich

Swiss company Airlight Energy is testing a low-cost, easily transferable solar collector that could mitigate energy costs for mining operations in remote locations.

The high-concentration photovoltaic thermal (HCPVT) system known as the solar sunflower is an ultra-high-concentration 12 KWel – 21 KWth stand-alone dish, currently under development in conjunction with IBM Research Zurich. It implements a multi-mirror parabolic dish topology with 40 square metres of active surface area and is designed to fit into a single shipping container when folded up.

Its small stature may be unassuming, but the sunflower actually magnifies the sun’s energy, thanks to water-cooled solar panels developed by IBM. From the panels, 25 photovoltaic chips are cooled by water flowing through micro-channels beneath them. This renders the cells just the right temperature for generating electricity.

The HCPVT system is designed for small to mid-sized energy consumers such as hotels, hospitals and small industries. However, Christopher P. Sciacca, manager of communications for IBM Research Zurich, said the system could be used to provide partial power for small or mid-size industrial operations.

“The system can concentrate the sun’s radiation 2,000 times," said Sciacca, "and convert 80 per cent of it into useful energy to generate 12 kilowatts of electrical power and 20 kilowatts of heat on a sunny day—enough to power several average homes. A large multi-dish installation could provide enough water for a town.

"A remote mine in a sunny region could benefit from both the energy output as well as the water, which could be shared with the mining crew,” he said.

Applications for the HCPVT are limited only by the imagination—and sunlight, of course. Warm water from the units can run a desalinator, for instance, driving seawater through a polymer membrane to produce up to 2,500 litres of fresh water every day. Away from the ocean, the unit can drive a water purifier to rid water of other unwelcome contaminants.

These units are also competitively priced because the solar mirrors, usually made from glass, are constructed from metallized foil.

The HCPVT system will be commercially available in 2017. In addition to a prototype currently running in Biasca, Switzerland, over the next 30 months, Airlight Energy and IBM will construct and install seven systems around the world for testing. Fine tuning the ideal application and geographical region depends on many factors.

“For the initial two prototypes, our criteria include a number of factors, some of which are very obvious, including direct normal irradiation (DNI) for the location, average temperatures and rainfall, accessibility, university partnerships and simply, what problem it addresses,” said Sciacca. “We measure this based on the DNI number, and the closer to 2,000 the better.”

In addition to residences, additional applications include remote hospitals, medical facilities, hotels and resorts, shopping centres and locations where available land is at a premium. Sciacca said the HCPVT system is definitely a viable option for mitigating expenses in remote locations, regardless of an operation's size.

“There are a lot of factors to consider when talking about reducing energy expenses,” he said. “But since the system is made from cement and foil, it's very inexpensive. And what other technology will provide you with heat, energy and clean water all in one unit?”

Airlight Energy and IBM are currently looking for suitable locations around the world at which to test the system. Canadians are encouraged to apply at www.ibm.biz/sunhcpvt.