This is a good PowerPoint by Lee Enterprises Expert, Mark Robertson, P.E., about gasification of biomass.  It talks about the uses and global potential for biomass gasification, including CHP, renewable natural gas, syngas refueling, liquid biofuels and transportation RNG.  It discusses the rise in biomass gasification plants less than 2MW, and discusses gasification technologies and good criteria for selection, including techno-economic analysis (TEA), environmental and waste management concerns, hazard and risk analysis, availability and reliability.   It also delineates the current challenges with respect to biomass gasification technologies.