Guava, a tropical fruit cultivated widely across India, has an important role in the food industry. Now its seeds, which are usually discarded as waste, are being used to produce biodiesel and biomass by Coimbatore-based start-up Buyofuel.
Guava seeds contain 15-20 per cent of oil that can be processed into biodiesel. The rich remainder of the seed, which is fibre-rich, can be utilised as biomass for industrial boilers and heating systems. These characteristics make guava seeds a highly efficient and versatile resource for biofuel production.
Sensing opportunity
“As the seeds are often discarded as waste, they offer an opportunity for sustainable repurposing. Buyofuel saw an opportunity to address both agricultural waste management and the rising demand for alternative energy,” said Kishan Karunakaran, Founder and CEO of Buyofuel.
The idea was simple but transformative — collect and convert guava seeds into biofuel. This approach aligned with Buyofuel’s vision of turning agricultural by-products into valuable, renewable energy solutions, he said.
Buyofuel went about identifying the calorific value and key metrics of guava seeds, ensuring they are a suitable and efficient co-firing agent for renewable energy applications. In addition, it developed innovative logistical solutions to handle and transport guava seeds efficiently, overcoming challenges associated with their collection and storage. “These achievements highlight Buyofuel’s commitment to introducing unconventional biofuel sources into the energy stream, enabling industries to adopt sustainable alternatives seamlessly,” he said.
Advantages, challenges
On the advantages of using guava seed biofuel, Karunakaran said it results in up to 80 per cent reduction in carbon emission compared to conventional diesel. “Furthermore, by repurposing agricultural waste, the initiative aims to reduce landfill usage and minimise the need for chemical fertilizers in the waste disposal process, thereby contributing more to sustainable farming and processing practices,” he said.
On disadvantages, he said the key challenges include the logistics of collecting guava seeds from remote regions and the high initial capital investment required for processing industries. “Despite these, Buyofuel has managed to address the logistical concerns through various innovative solutions and partnerships,” the company’s founder and CEO said.
Buyofuel currently has 4-5 clients who actively use or are showing interest in utilising guava seeds as a biofuel. They are exploring its potential to co-fire fossil fuels across multiple facilities and contribute to feeding renewable energy into the grid, showcasing its versatility and sustainability.
Alternative biofuel sources
Karunakaran said apart from guava seeds, Buyofuel is actively exploring and promoting alternative biofuel sources. The platform has made significant contributions by diverting mango seeds, turmeric spent, mustard husk and cashew nut shells into the energy stream.
“These innovative feedstocks provide sustainable and cost-effective solutions for industries aiming to transition to renewable energy,” he said.
Buyofuel is actively exploring various other resources that can be integrated into the energy stream, aiming to diversify the biofuel supply and reduce dependency on fossil fuels for industrial use. “By identifying and introducing innovative and sustainable feedstocks, Buyofuel continues to drive the transition toward cleaner energy solutions, enabling industries to achieve their sustainability goals more effectively,” said the start-up’s founder and CEO.
