7.10.2010

THE MILLENNIUM TECHNOLOGY PRIZE BOOSTS RESEARCH INTO GRÄTZEL CELLS

The first products based on Grätzel solar cells are already on the market, but low-cost energy-harvesting roofs and windows require further research. The Millennium Technology Prize has given new impetus to technology developers, including those based in Finland.

In 1989, by mimicking the processes in natural photosynthesis, Swiss chemist Michael Grätzel managed to build a type of solar cell that was completely new. In June 2010, when he received the Millennium Technology Grand Prize for his research, he expressed his gratitude to the global research community for developing his innovation further.

"There are at least 10,000 research papers in the dye-sensitised solar field. A world-wide community is now tackling the research issues," he said.

One of these researchers is Professor Peter Lund from Finland's Aalto University. Led by Professor Lund, the university's New Energy Technologies group began its research into Grätzel cells in 2000. Ten researchers are now employed on the subject and three dissertations are on their way. "Interest in researching Grätzel's technology has risen dramatically in the past five years," says Lund.

In February 2010, Professor Lund was searching for an opponent for a doctoral thesis being prepared by one of his researchers. Minna Toivola's work dealt with the preparation of Grätzel cells on steel surfaces and Lund decided to invite the best expert available. To his surprise, Professor Grätzel, busy father of the technology, accepted the assignment. He had just heard that he was one of the 2010 Millennium Technology Prize Laureates.

In April 2010, as opponent at the public defence of Toivola's dissertation, Professor Grätzel became familiar with Finnish research into his innovation. Researchers at the Aalto University had achieved very promising cell efficiencies for Grätzel cells manufactured on steel plate. When the method is ready for mass production, roofing components could be coated with energy-harvesting Grätzel cells at minimal extra cost.

Using building materials for electricity generation is one of the most promising applications for Grätzel's technology. The European Photovoltaic Industry Association (EPIA) estimates that 40% of all building roofs and 15% of all building facades in Europe are suitable for photovoltaic applications. In purely technical terms, roofs alone could generate up to 40% of total EU demand for electricity by 2020.

Commercialisation of the technology is also moving ahead. For example, the steel producer Corus and Dyesol, a manufacturer of Grätzel cell materials, are engaged in a joint venture to industrialise Grätzel cell technology on steel surfaces in the continuous manufacture of integrated building products.

Grätzel returned to Helsinki in June 2010. The three professors competing for the 2010 Millennium Technology Grand Prize met each other at Millennium Technology Week. The Grand Prize went to Professor Grätzel.

"Grätzel's victory was a very positive event. It brought photovoltaic research into the public consciousness," says Professor Lund. He hopes the resulting publicity will also bring new business partners to the research group at Aalto University.

The same wish is shared by a group several hundred kilometres to the north, in the City of Oulu. Eight years ago, researchers at VTT Technical Research Centre of Finland began testing Grätzel cell manufacturing using printing techniques. In recent years, research has focused on organic solar cell materials, an innovation developed by Sir Richard Friend, one of the 2010 Millennium Technology Prize Laureates.

Terho Kololuoma, Research Coordinator at the VTT Centre for Printed Intelligence welcomes new business partners. "We help companies commercialise new types of electronic products manufactured using printing methods," he says. Support for R&D in the building industry to integrate Grätzel cells into building products is on offer.

In his acceptance speech at the Millennium Technology Prize Award Ceremony in June 2010, Professor Grätzel expressed the wish that the awarding of the prize would help promote the new technology and add momentum to its further development. He pointed out that the production of energy from renewable sources must be developed quickly: while global energy consumption is growing, oil reserves are dwindling fast.

"By 2050, a 14-terawatt gap will need to be covered using renewable energy sources," he said.

Text: Petja Partanen / Tarinatakomo