Virtual power plants (VPPs) have become an integral part of modern energy systems by aggregating distributed energy resources (DERs) into a coordinated, adaptable, and responsive energy system. However, existing VPP systems often face challenges such as limited integration of diverse DERs, suboptimal energy distribution, and fluctuating output from intermittent sources like solar and wind. While many studies have addressed individual aspects of VPP operation, such as demand response, DER aggregation, or optimization techniques, a structured and comprehensive understanding of strategies to improve VPP efficiency remains lacking. This paper presents a systematic literature review conducted using Kitchenham’s methodology, synthesizing existing literature on enhancing VPP efficiency through the coordinated integration of wind, solar, and energy storage systems. The review evaluates studies employing modelling and simulation tools such as MATLAB/Simulink, focusing on optimization techniques and control strategies to reduce transmission losses, enhance operational intelligence, and support real-time grid responsiveness. By consolidating existing findings, this study identifies current trends, research gaps, and best practices that facilitate more efficient and resilient virtual power plant architectures suitable for smart energy systems.