BCC Research reports the global market for anaerobic digestors and landfill gas equipment was estimated at nearly $4.5 billion for 2013. Its study, Waste-Derived Biogas: Global Markets for Anaerobic Digestion Equipment, projects the market to grow to $7 billion by 2018, and register a five-year compound annual growth rate of 9.4 percent 2013 to 2018.