By Kal Kaur
Researchers at Rice University have developed a prototype solar energy technology that can convert water into steam without boiling the water. This revolutionary technology is based on the use of nanoparticles. With solar energy being a key solution for providing power without the requirement of fuel, this new technology could transform the supply of electricity on a global scale.
There is an unmet need to develop solar energy sources that are more compact, mobile and self-efficient and could potentially be of substantial demand within the developing countries and developed world.
The technology involves a process of light-to-heat conversion by using conductive nanoparticles using laser illumination. These nanoparticles are of submicrometer in size and capable of absorbing light energy in as little as a second when submerged in water. The absorption of light energy by these nanoparticles results in the release of steam that can reach temperatures as high as 100°C.
The use of solar powered technology to produce steam at such high temperatures is now forming the basis of developing devices to help sanitize medical equipment, a research and development effort that, if commercialized, could see easy transportation and easy operation of this technology in resource-limited areas of the world, particularly in developing countries.
Collective vibration of conducting electrons allows nanoparticles to absorb optical radiation. Following excitation of these nanoparticles, the energy is dissipated and this raises the temperature. When subjecting these nanoparticles in water to light energy, the difference in temperature between the nanoparticle surface and the cold water gives off steam at impressively high temperatures, creating a foundation to develop sophisticated solar steam technology.
Professor Naomi Halas, Rice University discusses the potential application for solar steam technology:
Video courtesy of Rice University.
Two main applications have been highlighted for this technology: 1) to sanitize medical and dental equipment; 2) to disinfect animal waste. Both applications could help reduce the transmission of diseases and infections that are still a critical problem in developing countries. Current tests have revealed that this technology can generate steam at temperatures as high as 270 Fahrenheit and has been high enough in temperature to kill heat-resistive microbes that are resilient in challenging conditions.