Shyam Rao Shirke, a mechanical contractor from Raipur has come out with the idea of producing bio-CNG from sewage sludge. Talking about his work he said, "I collected water from drains and made mini 'collector' to collect water bubbles, used a drum to make a gas holder. When tested the system was functional. I connected it to a gas stove and made tea. I built and installed it in a nullah. In three days enough gas was collected. Chhattisgarh Science and Technology gave me money to take it to the next level." Shyam Rao Shirke has patented production of bio-CNG from sewage sludge.