Waste-to-Biogas: BITS Pilani team develops iSTAR technology

The BITS Pilani has developed an innovative solution for managing landfill leachate, domestic septage, and food waste and also further the green fuel development in the country. A research team from the Hyderabad campus of BITS Pilani have developed a technology called iSTAR (Intelligently Stirred Thermophilic Anaerobic Reactor) which efficiently converts organic waste into methane-rich biogas, a valuable biofuel.

Led by Prof. P. Sankar Ganesh from the Department of Environmental Science and Technology, iSTAR is a single-stage advanced anaerobic digestion process designed to treat a variety of organic waste streams, including municipal solid waste, landfill leachate, faecal sludge, domestic septage, food waste, and sewage sludge.

With an impressive 85% conversion rate, the system generates biogas containing 60–70% methane. The proposition makes the technology highly efficient waste-to-energy solution.

Beyond biogas production, the process yields value-added by-products such as nutrient-rich biofertilizer, acids, and alcohols. The technology also offers faster waste treatment and requires less space for installation and operation.

A key feature of iSTAR is its continuous remote monitoring system, which tracks pH, temperature, and pressure to maintain optimal conditions and address potential issues. Additionally, the reactor does not require water input, except when processing dry feedstock like leaf litter and agro-residues.

Designed for versatility, iSTAR can process liquid and solid organic waste either independently or in combination. According to reports, with a daily input of 100 kg of organic waste, the system can generate 10,000 liters of biogas—equivalent to 92 commercial LPG cylinders annually.

With its simple and user-friendly design, iSTAR is easy to fabricate, install, operate, and maintain—even by housekeeping staff. The technology is ready for large-scale implementation, making it an ideal solution for urban and rural local bodies, restaurants, institutions, and gated communities. Additionally, installations may qualify for capital cost subsidies from the Ministry of New and Renewable Energy.