Collaborating with the Indonesian Biomass & Bio Energy Association (ABBEI), UGM Center for Agrotechnology Innovation, and the Indonesian Solid Waste Forum (ISWF), Department of Mechanical Engineering Education, last Tuesday (18/2) held a guest lecture entitled "Best Practice of Solid Waste Treatment Technology in Germany and Other Country ”which on that occasion brought in a waste management expert from Germany, Hans Joachim Alfeld. The event was held in the Hall Floor 3 KPLT FT UNY.