Energy Audit Approaches and Outcomes for Enhancing Energy Efficiency in Small & Medium Enterprises

This structured narrative review evaluates energy-audit approaches and reported outcomes relevant to small and medium enterprises (SMEs), with emphasis on industrial applications and resource-constrained implementation. The evidence base combines Indian case studies with international multi-enterprise evaluations and current audit guidance. Studies were compared according to audit scope, measurement practices, significant energy uses, recommended energy-conservation measures, economic indicators, implementation status, and reported barriers. Across the six Indian studies, power-factor or broader power-quality assessment appeared in all cases, motor or fan efficiency in five, and lighting-system improvement in three. Frequently recommended measures included efficient motors and drives, LED lighting, capacitor or automatic power-factor-correction systems, compressed-air leak control, load balancing, harmonic mitigation, operating-schedule optimization, and improved monitoring. One cable-manufacturing case reported an investment of INR 0.675 million with annual savings of INR 1.191 million and a payback of approximately 6.4 months; another medium-scale industrial audit reported a 25-month payback. Programme-level evidence from Sweden reported net annual savings of 340 GWh, equivalent to about 6% of participating firms' energy use. The synthesis shows that audits are most effective when recommendations are ranked by verified baseline data, technical feasibility, financial return, and implementation risk, followed by measurement and verification. A practical SME-focused audit framework is proposed to convert diagnostic findings into implementable and verifiable actions.