Panasonic Says New Artificial Photosynthesis Method Is World's Most Efficient
Panasonic said Monday it has developed a new system for artificial photosynthesis that can remove carbon dioxide from the air almost as well as plants do, as part of the company's push to join an industry-wide trend toward greener tech.
The company said its system uses nitride semiconductors, which are widely used in LEDs (light-emitting diodes) to convert light to energy, and a metal catalyst to convert carbon dioxide and water to formic acid, which is widely used in dyes, leather production and as a preservative.
Carbon dioxide is a major pollutant and considered to be a main cause of the "greenhouse effect," which most climate scientists believe causes global warming.
Panasonic has struggled with its traditional electronics business and has made eco-friendly products and practices the key element in its turnaround plan. The company is hoping to leverage its large rechargeable battery and solar businesses, while joining the industry in embracing technologies that are friendlier to the environment. The issue is an important one with customers, as demonstrated by the the outcry earlier this month when Apple was forced to rejoin a green standards program when clients complained about its earlier withdrawal.
As the name implies, artificial photosynthesis seeks to imitate the chemical conversion performed in green plants, which use sunlight to power a chemical reaction that converts water and carbon dioxide into carbohydrates like sugar. Theoretically the process is superior to current solar applications, which produce electricity that is inefficient to store, but current implementations are costly and degrade quickly during use.
Panasonic said the system can convert carbon dioxide and water to formic acid with an efficiency of 0.2 percent in laboratory conditions, which is similar to the conversion rate for green plants. The efficiency refers to the portion of the incoming light energy stored in materials produced during the process.
The company aims to eventually employ the system in industrial applications that produce high quantities of carbon dioxide, such as power plants and incinerators.
Nitride semiconductors have long been used in LEDs and lasers, but in recent years have also been used in photovoltaic applications that convert light to electricity. Panasonic said it uses a thin-film version of the chips for the photosynthesis application.
The Osaka based company said it holds 18 patents in Japan and 11 overseas relating to the system, which it will present at a solar conference in Pasadena, California.