This book presents selected peer reviewed articles from the 3rd International Engineering Research Symposium- IERS 2025, held at Colombo, Sri Lanka, under the theme of “Engineering Solutions for Climate Actions, Digital Transformations and Green Industries”. It highlights the latest advancements in engineering research, innovations, and technological principles aimed at driving the economy and the industry towards carbon net-zero goals, sustainable development and digital transformation. IERS2025 covers the areas of Chemical and Process Engineering, Climate Change Mitigation & Adaptation, Climate Smart Agriculture, Computer Science, IoT, AI, Cyber Security, Block Chain & Wireless Communication, Electrical, Electronic & Telecommunication Engineering, Energy & Environmental Management, Green Infrastructure & Civil Engineering, Industrial Digitalization and Manufacturing Innovations, Mechanical & Mechatronics Engineering, Water Management & Hydrology and other Engineering discipline relevant to the theme of IERS 2025.