Farmers across the state have come to depend a lot on groundwater through the use of pumps. Power to pumps has become an electoral issue since this power is sometime not good quality and is supplied irregularly. Pumps are also used to bring water from nearby lakes and open wells. In some places, diesel-based engines are used to operate the pump.
C Rajasekaran, a farmer from Vettaikaran Iruppu of Kilvelur Taluk in Nagapattinam district, has come up with an eco-friendly, renewable alternative to the use of electricity or diesel engine to drive the pump. He has done some indigeneous engineering to run his irrigation pump on oil from punnai (Alexandrian Laurel tree) seeds. His is a 5hp motor and he has reduced his dependence on diesel and electricity.
About 600 ml punnai oil can run the motor for an hour. In the case of diesel he has to use about 800 ml for the same one-hour irrigation. And a litre of diesel costs Rs 70 today.
“If a farmer has two trees on his punnai land, he can reduce his diesel costs considerably,” says Rajasekaran.
The punnai trees don’t need much care to grow. Cattle and goats do not eat the leaves of the tree which is hard, pest-resistant and low maintenance.
Within five years of planting, a farmer can get 4 to 20 Kg of punnai seeds in a year. After 10 years, the yield can go up to 10 to 60 kg. The yield increases as the tree grows older.
The punnai trees attract bees and bats. While the bees help to pollinate, the bats help by eating the fruits and and excreting the seeds in the field. “My only job is to collect the seeds spilled all over my field, dry them for six days, after which they can be broken open and oil extracted from the kernel, similar to groundnut,” he said.
The cost of producing one litre of punnai oil works out to Rs 10, as against Rs 70 per litre of diesel.
“I need to operate the motor only during non-rainy days and hence I need the oil for only five months in a year,” says Rajasekaran.
He sells the surplus punnai oil from his trees to temples at Rs 42 a litre. After extracting the oil, he also gets 300 grams of punnai cake from I kg of seed kernel and uses it as manure for his farms.
Punnai oil has lubricating properties and that helps in maintaining engine performance. “If you notice carefully, motor engines run through diesel start rusting in five years. No rust forms if punnai oil is used and the engine emits little noise during operation. I have been using punnai oil for the last four years, and the performance of the pump is as good as if not better than with diesel,” says Rajasekaran.
Rajasekaran says government should promote use of punnai oil as fuel after doing some research so precious diesel and foreign exchange can be saved. “When there is so much of awareness on growing trees and increasing green cover, the government should also create awareness on the punnai tree. In Tamil Nadu, if every farmer grows at least two trees, in five years his irrigation problem will be solved. But till date nobody has evinced interest in the humble punnai tree,” he says with a glum face.
Historically, punnai trees have been valued highly in Tamil Nadu. Temple lamps and household lamps used to be lit using punnai oil but with the advent of diesel and electricity the precious tree has been forgotten.
C Rajasekaran can be reached on mobile: 97510 02370