RAPID CITY,
S.D. (March 17, 2016) – Researchers from South Dakota School of Mines &
Technology have successfully converted tomato waste into electricity, paving
the way for an efficient low-cost new alternative energy source.
The research
findings of Venkataramana Gadhamshetty, Ph.D., and his team were presented at
the 251st National Meeting & Exposition of the American Chemical Society
(ACS) in San Diego on Wednesday.
The pilot
project involves a biological-based fuel cell that uses tomato waste left over
from harvests in Florida. The inherent characteristics of the decomposing waste
make it a “perfect fuel source” for enhancing electrochemical reactions,
Gadhamshetty said.
In addition to
imperfect tomatoes not suitable for grocery store shelves, waste can come from
the leftovers of manufacturing processes of sauces, ketchup and other cooking
products. “A lot of tomato waste is produced with a lot of chemical energy
sitting there. We wanted to see if we could use this waste as a source of
electrons,” Gadhamshetty said.
Researchers
tested the defective tomatoes in a new electrochemical device built at the
South Dakota Mines campus, which degrades tomato waste and then extracts
electrons.
The power
output from their mini reactor is small: 10 milligrams of tomato waste can
result in 0.3 watts of electricity. But the researchers note that with an
expected scale up and more research, electrical output could be increased by
several orders of magnitude.
“It might be
possible to one day put this device at the bottom of my kitchen sink” to
convert waste into household electricity, Gadhamshetty said.
This
alternative fuel source is inexpensive technology because operations can be
conducted at room temperature requiring no major investment of materials.
Gadhamshetty
and SD Mines graduate student Namita Shrestha are collaborating on the project
with Alex Fogg, an undergraduate chemistry major at Princeton University. Other
project collaborators include Daniel Franco, Joseph Wilder and Simeon Komisar,
Ph.D., at Florida Gulf Coast University.
“I’m really
excited about this research. I come from a small country, Nepal, and we have
power cut off as much as 20 hours in a day, so this could really help
developing countries,” Shrestha said. “We cannot afford expensive technologies
like waste treatment.”
Gadhamshetty
began the research several years ago as a professor at Florida Gulf Coast
University. He stresses the project is important to Florida, where tomatoes are
a key crop, because the state generates 396,000 tons of tomato waste every year
but lacks a good treatment process.
According to
Shrestha’s calculations, there is theoretically enough tomato waste generated
in Florida each year to meet Disney World’s electricity demand for 90 days,
using an optimized biological fuel cell.
“Research that crosses
disciplines like this project, involving biochemical engineering and civil
engineering, is increasing at Mines and can make a great contribution to
solving 21st century problems,” said Heather Wilson, South Dakota Mines
president.
The American
Chemical Society is the world’s largest scientific society. The organization’s
meeting is being attended by 15,000 researchers and exhibitors, with only a handful of
the wide range of their scientific research projects selected for promotion
through news releases and press conferences.
Gadhamshetty’s
research has been featured in international media outlets including Newsweek, CNN Money, Yahoo! News, MSN and international newspapers such as Times of India. Gadhamshetty
was also invited to talk with the BBC World Service Newsday program with more than 280 million listeners.
The American
Chemical Society news release featuring the interview with Gadhamshetty and Shrestha
can be viewed on YouTube.
“This attention
means a great deal to my scientific career, especially for these early stages
of my career. It demonstrates we are working on innovative solutions to address
some of the pressing environmental challenges facing the modern society. ”
Gadhamshetty said.
In 2015
Gadhamshetty was named by the National Science Foundation with the most prestigious
NSF CAREER award supporting junior faculty who exemplify the role of
teacher-scholars by integrating outstanding research and excellent education.
That carries a $500,000 research grant.
“I would like to take this opportunity to thank Drs. Molly Gribb, Scott Kenner, Ed Duke, and Robb Winter for helping
me transition at Mines when I arrived in 2014, and all the wonderful students, collaborators, and
advisors," Gadhamshetty said.