Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Solar Energy News .




SOLAR DAILY
Off-grid sterilization with Rice U.'s 'solar steam'
by Staff Writers
Houston TX (SPX) Jul 23, 2013


Rice University graduate student Oara Neumann, left, and scientist Naomi Halas are co-authors of a new study about a highly efficient method of turning sunlight into heat. They expect their technology to have an initial impact as an ultra-small-scale system to treat human waste in developing nations without sewer systems or electricity. (Credit: Jeff Fitlow/Rice University).

Rice University nanotechnology researchers have unveiled a solar-powered sterilization system that could be a boon for more than 2.5 billion people who lack adequate sanitation. The "solar steam" sterilization system uses nanomaterials to convert as much as 80 percent of the energy in sunlight into germ-killing heat.

The technology is described online in a July 8 paper in the Proceedings of the National Academy of Sciences Early Edition. In the paper, researchers from Rice's Laboratory for Nanophotonics (LANP) show two ways that solar steam can be used for sterilization - one setup to clean medical instruments and another to sanitize human waste.

"Sanitation and sterilization are enormous obstacles without reliable electricity," said Rice photonics pioneer Naomi Halas, the director of LANP and lead researcher on the project, with senior co-author and Rice professor Peter Nordlander. "Solar steam's efficiency at converting sunlight directly into steam opens up new possibilities for off-grid sterilization that simply aren't available today."

In a previous study last year, Halas and colleagues showed that "solar steam" was so effective at direct conversion of solar energy into heat that it could even produce steam from ice water.

"It makes steam directly from sunlight," she said. "That means the steam forms immediately, even before the water boils."

Halas, Rice's Stanley C. Moore Professor in Electrical and Computer Engineering, professor of physics, professor of chemistry and professor of biomedical engineering, is one of the world's most-cited chemists. Her lab specializes in creating and studying light-activated particles. One of her creations, gold nanoshells, is the subject of several clinical trials for cancer treatment.

Solar steam's efficiency comes from light-harvesting nanoparticles that were created at LANP by Rice graduate student Oara Neumann, the lead author on the PNAS study. Neumann created a version of nanoshells that converts a broad spectrum of sunlight - including both visible and invisible bandwidths - directly into heat.

When submerged in water and exposed to sunlight, the particles heat up so quickly they instantly vaporize water and create steam. The technology has an overall energy efficiency of 24 percent. Photovoltaic solar panels, by comparison, typically have an overall energy efficiency of around 15 percent.

When used in the autoclaves in the tests, the heat and pressure created by the steam were sufficient to kill not just living microbes but also spores and viruses.

The solar steam autoclave was designed by Rice undergraduates at Rice's Oshman Engineering Design Kitchen and refined by Neumann and colleagues at LANP. In the PNAS study, standard tests for sterilization showed the solar steam autoclave could kill even the most heat-resistant microbes.

"The process is very efficient," Neumann said. "For the Bill and Melinda Gates Foundation program that is sponsoring us, we needed to create a system that could handle the waste of a family of four with just two treatments per week, and the autoclave setup we reported in this paper can do that."

Halas said her team hopes to work with waste-treatment pioneer Sanivation to conduct the first field tests of the solar steam waste sterilizer at three sites in Kenya.

"Sanitation technology isn't glamorous, but it's a matter of life and death for 2.5 billion people," Halas said. "For this to really work, you need a technology that can be completely off-grid, that's not that large, that functions relatively quickly, is easy to handle and doesn't have dangerous components. Our Solar Steam system has all of that, and it's the only technology we've seen that can completely sterilize waste. I can't wait to see how it performs in the field."

Paper co-authors include Curtis Feronti, Albert Neumann, Anjie Dong, Kevin Schell, Benjamin Lu, Eric Kim, Mary Quinn, Shea Thompson, Nathaniel Grady, Maria Oden and Nordlander, all of Rice. The research was supported by a Grand Challenges grant from the Bill and Melinda Gates Foundation and by the Welch Foundation.

.


Related Links
Rice University
All About Solar Energy at SolarDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





SOLAR DAILY
Two in one solution for low cost polymer LEDs and solar cells
Ulsan, South Korea (SPX) Jul 23, 2013
Considerable improvement in device performance of polymer-based optoelectronic devices was reported by researchers from Ulsan National Institute of Science and Technology (UNIST), South Korea. The new plasmonic material, can be applied to both polymer light-emitting diodes (PLEDs) and polymer solar cells (PSCs), with world-record high performance, through a simple and cheap process. The co ... read more


SOLAR DAILY
Microorganisms found in salt flats could offer new path to green hydrogen fuel

CSU researchers explore creating biofuels through photosynthesis

Drought response identified in potential biofuel plant

Euro Parliament committee endorses cap on using crops for biofuels

SOLAR DAILY
Spain museum uses robot to help restore works

Chips that mimic the brain

Humanoid robot that could save people in disasters unveiled

Thin 'e-skin' could lead to more 'touchy-feely' robots

SOLAR DAILY
SOWITEC Mexico - strengthening its permitted project pipeline

Sky Harvest To Acquire Vertical Axis Wind Turbine Technology And Manufacturing Facilities

Wind Energy: Components Certification Helps Reduce Costs

Wind power does not strongly affect greater prairie chickens

SOLAR DAILY
Hydrogen cars quickened by Copenhagen chemists

Toyota, Ford end hybrid partnership

LADWP Officials Announce Expanded Electric Vehicle Program

EU largely backs France in German Mercedes row/

SOLAR DAILY
Greenhouse gas seen as clean source of electricity

Oil prices tumble on poor China data

Oil market under pressure from China demand fears

Now gas-rich Israel goes for oil in East Med

SOLAR DAILY
Paraguay upset over Argentine nuclear plant near border

Fukushima nuclear clean-up costs rise as steam seen again

Radioactive water leaked into sea at Fukushima: TEPCO

Australia minister calls for more uranium development

SOLAR DAILY
Americans continue to use more renewable energy sources

Sweden's Vattenfall hit by $4.6-bn charge as energy demand plunges

Six Tech Advancements Changing the Fossil Fuels Game

Free market is best way to combat climate change

SOLAR DAILY
Loss of African woodland may impact on climate

US debt deal helps Philippines save forests

Black Bears Return to Missouri Indicates Healthy Forests

Most flammable boreal forests in North America become more so




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement