Little subsidy takes focus away from PAU’s dry fermentation biogas plant

With paddy harvesting about to commence, the issue of stubble burning, which results in increase in air quality index (AQI), has again come to the fore.

Though the state government’s move to set up compressed biogas plants (CBG) have hit a roadblock, dry fermentation biogas plant developed by Punjab Agricultural University (PAU) can come to the rescue.

However, inadequate subsidy offered for setting up these plants has kept farmers away.

Last year, the PAU’s dry fermentation biogas plant (straw based) was approved by the Ministry of New and Renewable Energy, New Delhi.

Dr Sarbjit Singh Sooch, Principal Scientist, Department of Renewable Energy Engineering, PAU, said, “The cost of setting up of this biogas plant is Rs 3 lakh but the subsidy is just Rs 14,500. The government should at least give 70 per cent subsidy so that it’s widely accepted by the farmers.”

Explaining the technology, Dr Sooch said, “Dry fermentation is a batch process. Unlike traditional cow dung-based biogas plants, which require daily feeding, this plant needs to be filled only once in three months and uses paddy straw in batches of 15 quintals. It generates three to four cubic metres of biogas per day, equivalent to three cylinders a month. Once the digester is loaded and activated, it will produce sufficient gas for a period of three months.”

With the installation of these plants, a large quantity of paddy straw can be consumed for biogas production. The specialty of this plant is that daily feeding of cattle dung is not required and one can produce biogas equivalent to 30 to 35 cylinders per year through this technique.

“It generates slurry every three months, which is easy to manage. Its life cycle is around 15 years. Moreover, the entire structure is above the ground,” added Dr Sooch.

“At present, just one farmer has set up dry fermentation biogas plant. Twenty plants have been established at the PAU’s KVKs and four in Haryana. The KVKs are using the plants for demonstration purpose,” he said.