About 70 percent of the Earth’s surface is covered in water, and just less than 97 percent of this water is held in the world’s oceans. As a resource in its own right, water is hugely abundant, but harnessing it in efficient ways that benefit humanity proves challenging for researchers.
Turning water into steam is one of the most popular ways of utilizing this resource for a variety of applications, such as power generation and water purification. However, current methods of creating steam involve heating the entire bulk of water, which outputs excessive heat and requires substantial amounts of energy.
Hadi Ghasemi, a new professor in the department of mechanical engineering at the UH Cullen College of Engineering, is researching ways to create steam more efficiently, and the possibilities are revolutionary. So revolutionary, in fact, that he has been nominated for the 2014 World Technology Award in the Energy category, an award presented by The World Technology Network (WTN) in association with media giants Fortune and Time Magazine.
Ghasemi began his research into heat transfer technology while performing postdoctoral research at the Massachusetts Institute of Technology (MIT). He and his research group developed a new material that sits on the surface of water and uses solar energy to heat the very top layer of water to the point of steaming without having to heat the entire container.
The material is a thin disc made up of two layers. The bottom is made of spongy carbon that helps the disc float and acts as a thermal insulator to keep solar energy from dissipating. The top layer uses graphite that creates hot spots when exposed to sunlight, which draws the water up through the carbon foam. When the water touches the hot spots, it steams. With solar energy concentrated to 10 times that of a normal sunny day, the material converts 85 percent of the incoming solar energy into steam – a highly efficient rate.
Creating a technology that efficiently converts water to steam could quite literally change the world. Ghasemi said the scope of applications for this material is wide and could affect millions.
“We have developed a new approach for making steam that is much more efficient than the current approaches. If you’re looking at the big picture, where 80 percent of the world’s electricity is produced by steam, this new efficient approach, if implemented in the solar steam generation power plants, it would be a huge advantage to the sustainable energy world,” Ghasemi explained. “But that is not the only application of this structure.”
Steam is still largely used in rural areas of the world as a sanitation device, particularly in medical practices. “One thing that I’m going to emphasize is that solar energy is the only source of energy in many remote areas, like villages,” he said. “If you can do something with solar energy, that’s really advantageous. In a remote area, you need to sterilize equipment which are driven by steam.”
It’s in these same areas that finding clean drinking water is also a challenge. “Now we know that drinking water is [relatively] rare and producing clean drinking water is important. To produce drinking water, you need to evaporate the salty [or unclean] water, and one of the approaches is to convert it to steam and then condense back the steam to make drinking water,” Ghasemi said. “So the structure that we have developed, you can put this structure on top of a big water reservoir under the sun, and with the low concentration of the sun – a low amount of energy – you can produce steam, and with that, desalinate the water.”
Desalination, Ghasemi said, is important closer to home as well. Places like California that are experiencing severe drought are already experimenting with desalinating ocean water for drinking purposes. Chemical companies both domestic and abroad can also benefit from the technology. Instead of waiting years for the water in chemical waste ponds to evaporate, enabling companies to collect and dispose of waste, groups can evaporate the water in a much quicker and more efficient manner.
Ghasemi said he didn’t set out to blaze these new trails, but he’s glad he did. “The idea came by chance, we were thinking about this problem for a while in our group, and we did some experimenting. After a while I came up with this idea that we may use the two layers to be able to produce steam,” he said. “I think I’m happy I’ve gone one step forward in science to be able to help people and improve the quality of people’s lives. I think science is for improving the quality of life, and we are here to make this happen. It’s a very happy moment for me, but at the same time, I feel more responsibility to do something bigger.”
His successes haven’t gone unnoticed, as illustrated by his WTN award nomination. In the Energy category, he is joined by heavyweight nominees like Elon Musk, CEO of SpaceX and Tesla Motors, and Tod Hynes, founder and president of XL Hybrids and MIT senior lecturer. Other categories include nominees like Mark Zuckerberg (IT Software category), the founder of Facebook, and Neil DeGrasse Tyson, astrophysicist and host of the wildly popular “Cosmos: A Spacetime Odyssey” television series.
The WTN award ceremony and summit won’t take place until November, but in the meantime, Ghasemi said he’s happy to see the vast potential of the research he’s performed so far. “I didn’t have any intentions when I started this work, but now I think I can help people afford better futures for themselves,” he said.