Leading countries include China, India, and Brazil. In the East African region, Tanzania has had the greatest success where CARMATEC successfully promoted and installed fixed dome biogas digesters. More than 1,000 digesters have been installed and are being maintained by a cadre of trained local technicians. The fixed biogas digesters cost between $ 800 and 1, 300 for a local Tanzanian NGO is now promoting a simple low cost Tubular Plastic Biogas digester costing approximately $150. The gas produced is mainly used for cooking and lighting. These costs are likely to vary for other countries depending on labor and material costs.