Biodiesel extraction from non-edible waste is one of the most effective solutions to address the challenges involved with the energy consumption and environmental concerns. Algae are solitary or multilayer photosynthetically living that life in a humid environment on dry soil or floating in different types of water, including such groundwater, freshwater, sewage, and in the form of heat and light or bright sun. The investigation is performed at pure diesel and algae biodiesel at 20% blend (AlgaeB20) - with three compression ratios (16:1, 17:1, 18:1). and its established with variable percentage is used to conduct experiment. The investigation's observed with compression ratio the emission such as CO and HC are decreased 9% to 15% but the NOx emission is increased 20%). While increasing the compression ratio the CO and HC emission is increased by 12% however the NOx emission is controlled 18% to 25%. So, the NOx emissions can be effectively reduced by using 20% algae blend. © 2023 Elsevier B.V., All rights reserved.