John Yirijor is a lecturer in Academic City University’s Department of Mechanical, Industrial & Systems Engineering. His expertise spans sustainable building materials, agro-waste valorisation, composite materials, renewable energy, bioenergy systems and materials characterisation. His work connects materials innovation with circular-economy approaches, mechanical performance and sustainable energy applications. He teaches engineering thermodynamics, fluid mechanics, mechanics of materials, thermal engineering, materials science, environmental engineering, and multidisciplinary design, helping students apply theory to practical and professional contexts. He holds an MSc in Theoretical and Applied Physics from the African University of Science and Technology and a BSc in Applied Physics from the University for Development Studies, and is currently pursuing a PhD. His work has been recognised through Academic City’s Research Excellence Award and competitive Pan-African and Nelson Mandela Institute scholarships. He contributes to experiential, context-responsive education and interdisciplinary collaboration at Academic City.