The Hindu             22.11.2013

Students tap energy from scrap

What happens to tonnes of vegetable oil that are reused
in Puducherry’s many hotels, restaurants and roadside eateries? What
about the old gears and metal rusting away in scrap shops? Or shavings
and bones that are piled up when the fish market closes for the day?

Little
thought goes into what happens to everyday residue and leftovers. But
students from Puducherry schools clearly have their eyes and ears open.
The selected projects that have made it from the Union Territory to the
National Children’s Science Congress (NCSC) in Bhopal this year have all
capitalised on discarded material, turning waste into energy and
resource.

The NCSC is an annual affair that
cultivates scientific temperament in school children by prompting them
to apply scientific concepts to problems and issues around them over a
period of three months. This year a total of 178 projects were presented
from Karaikal, Mahe, Yanam and Puducherry at the district level.

From
a total of 29 projects selected for State level, six have made it to
the national finals, of which the top two will also get to present at
the Indian Science Congress in Jammu and Kashmir.

Mira
Arabinth and his team of Class XI boys from Petit Seminaire, believe
every tiny amount of energy counts. The boys have come up with a
proposal to convert mechanical energy into electrical energy, from the
pressure exerted by vehicles when crossing the speed breakers. “This
idea works better at toll gates, where there are eight lanes and
multiple speed breakers, with one vehicle crossing at one time,” says
Arabinth.

A contraption designed on the rack and
pinion model captures, converts and stores the energy. The boys
fashioned it from gear in scrap shops. “The challenge for us now is to
convert this variable current into steady flow of electricity before the
national-level presentation,” says Arabinth.

Around
15 watts of energy can be generated, depending on the mass of the
vehicle. “Even if it burns a lamp, it is energy and can help tide power
crisis,” says S. Midhune.

The youngest members among
the selected teams, who finished second, are girls of Class VII from St.
Patrick Matriculation School, who have tried extracting biodiesel from
used vegetable oil.

“We have read biodiesel can be
extracted using castor oil. We thought why not go for a more economical
option by using residue vegetable oil,” says V. Nivetha.

“Some
big hotels told us they sell the reused oil to petty shops for frying
purposes,” says S. Subitshaa, adding that an average restaurant used up
at least 40 litres per month.

The students confirmed
biodiesel by testing it in a lab and used it successfully as a stain
remover, says D. Beulah, guide teacher. “Now we are trying to use it in a
second-hand vehicle”.

In putting scientific concepts
into practice, students came across new experiences. For girls from St.
Joseph School of Cluny, the project was the first time they used wood
stoves, says Mahalakshmi. The team compared four variations like
charcoal, pellets, firewood, sawdust of both the casuarina and blueberry
wood to conclude on the most efficient source of energy. “There are a
lot of villages where wood stoves are used, causing breathing and other
problems,” says O. Anjana, her teammate. “Our study shows blueberry
pellets are a greener, cheaper and more efficient alternative,” says
Francita.

N. Narendiran and team, also from Petit
Seminaire, have tried to compare the most productive resource for biogas
production — prawn and fish waste or vegetable waste. “We visited the
market and found that much of the waste is left as litter on road
corners. By producing biogas from them, we can channel them for cooking
meals in governemt hostels for mid-day meals in schools,” says
Narendiran. While there was marginal difference in burning time, the
team found prawn and fish waste produces gas in three days, while it
takes double the time for vegetable waste.

Disadvantage government schools

The
number of participating schools this year has gone down. Except for two
schools in Mahe, who make up the selected six, only private
institutions from Puducherry have made it to the national level.
Government, rural and Tamil-medium schools figure nowhere in the top.
There is need to level the playing field, feel members of the Puducherry
Science Forum, the local organising body.

The
question is who will spend for the projects in government schools, says
K. Vijayamurthy, Liasion Officer, Puducherry Science Forum. The
Education Department must motivate teachers, who in turn can motivate
students, he adds.