The exponential growth of big data has led to a significant increase in the volume and complexity of data being generated and stored. This trend has created a huge demand for secure storage and processing of big data. Cryptography is a widely used technique for securing data, but traditional cryptography algorithms are often too resource-intensive for big data applications. To address this issue, light weight cryptography algorithms have been developed that are optimized for low computational overhead and low memory utilization. This research paper explores the use of a new sustainable algorithm that utilizes a lightweight cryptographybased key management scheme to optimize MapReduce security and computational efficiency in Hadoop clusters. The proposed sustainable MapReduce algorithm aims to reduce memory and CPU allocation, thereby significantly reducing the energy consumption of Hadoop clusters. The paper emphasizes the importance of reducing energy consumption and enhancing environmental sustainability in big data processing and highlights the potential benefits of using sustainable lightweight cryptography algorithms in achieving these goals. Through rigorous testing and evaluation, the paper demonstrates the effectiveness of the proposed sustainable MapReduce algorithm in improving the energy efficiency and computational performance of Hadoop clusters, making it a promising solution for sustainable big data processing.