‘Perovskite’, a next-generation solar cell with good performance and low cost… Hanwha, US, and Britain compete for commercialization

Input 2021.01.06 06:00

The advantage of being light and inexpensive… Homework that complements weak durability
US government “support 20 million dollars for perovskite solar cell research”

As investment in new and renewable energy such as solar and wind power increases, a material called’Perovskite’ is drawing attention. Solar cells made of perovskite are considered to be the next generation solar materials because they are cheaper than silicon solar cells that are widely used and can produce a lot of power. Although solar power is an eco-friendly energy source that does not emit greenhouse gases, it has been criticized for its inferior energy efficiency and economy compared to fossil fuel power generation such as coal. Governments and energy companies are accelerating the commercialization of perovskite solar cells to overcome this limitation of solar power.

The US government already announced in August of last year that it will provide 20 million dollars (about 21.7 billion won) for research and development of next-generation perovskite solar cells. The US Department of Energy (DOE) said, “Solar cells made of perovskite have excellent performance and low production cost, so their potential is high.” However, in order for perovskite solar cells to become competitive, we will secure sustainability and durability through R&D It should be done,” he explained the background of the application.

Perovskite is a material that has a crystal structure with excellent electrical conductivity, and is made by mixing inorganic and organic substances. It was first used in solar cells in 2009, but the photoelectric efficiency (the efficiency of converting light into electricity) was only 3.8% at that time. After 10 years of research, the photoelectric efficiency of perovskite solar cells has also increased to about 25% as of last year. However, perovskite batteries are still experiencing difficulties in commercialization, as they cannot overcome the disadvantage of rapidly deteriorating performance when exposed to moisture and heat. Experts are trying to solve this problem by grafting perovskite into existing silicon batteries with stability.

The photovoltaic industry is paying attention to the fact that perovskite solar cells are lighter and more flexible than conventional silicon solar cells, have simple manufacturing processes, and lower production costs by up to a third. Silicon solar cells, which are currently generally used, have to undergo a process of processing at a temperature of 1,400 degrees Celsius or higher using expensive equipment. Perovskite can be processed at a relatively low temperature of 100 degrees by using cheaper equipment, which can reduce cost. In addition, the thickness is light, as it is about 1-60th of the silicon solar cell.

Researchers and companies at home and abroad are speeding up R&D, seeing that if perovskite solar cells that take advantage of these advantages are commercialized, they will be able to catch two rabbits: cost reduction and energy efficiency improvement.

In Korea, Hanwha Q Cells, the solar power division of Hanwha Solutions, started to develop perovskite solar cells (tandem cells) at the end of last year. Hanwha Q CELLS offers Sungkyunkwan University, Korea University, Sookmyung Women’s University, Chungnam University, NCD, Yas, Daeju Electronic Materials (078600)It plans to form a consortium with such companies to secure and commercialize tandem cell technology for the next three years. About 20 billion won will be invested in this research.

The tandem cell is manufactured in the form of stacking perovskite, a next-generation solar material, on top of the existing silicon solar cell, and the company explained that it can obtain higher efficiency compared to the existing silicon solar cell. An official of Hanwha Solutions said, “Compared to the theoretical efficiency limit of a silicon solar cell at 29%, the maximum efficiency of a tandem cell can be up to 44%.” He said, “We will continue to recruit professionals.”

In the US, solar startup EMC is developing a low-cost process for manufacturing perovskite solar modules with the support of research and development from the US Department of Energy. EMC has partnered with Eastman Kodak, once synonymous with film, to utilize Kodak’s roll-to-roll (roll-to-roll, a method of manufacturing electronic devices on a rotating roll wound with a thin material such as plastic or metal foil) printing technology. It plans to mass-produce 100% perovskite solar modules. “When this process technology is completed, we expect to be able to produce 4GW (gigawatt) of solar modules per year,” said Stefan DiLuca, CEO of EMC.

In addition, Oxford PV, founded by researchers at Oxford University in the UK, announced in December last year that it recorded a power generation efficiency of 29.5% with a perovskite-silicon hybrid battery. Polish Saul Technologies, Chinese solar companies Suntech and Trina Solar are also conducting research to increase the efficiency of perovskite solar cells.

Sang-il Seok, professor of energy and chemical engineering at UNIST, said, “Perovskite will not be used as a substitute for existing silicon solar cells, but will be used as an aid to increase the competitiveness of existing silicon solar cells by grafting it to silicon. “Solar cells are not suitable for use in cities with many buildings in terms of weight, design, and efficiency, so it is expected that the utilization of perovskite solar cells in the city will increase in the future.”