Industrial Utility Efficiency

# Saving Energy in Automotive Assembly

### A. Introduction

This Midwestern automotive assembly factory has two major production areas called the “East” and “West” facilities. The objective of the engineering staff at this company is to optimize the compressed air energy costs as they relate to the number of vehicles manufactured per day. The task at hand is to continue to ensure the reliable supply of compressed air to all processes, while reducing the energy costs.

### E. Conclusion

This automotive assembly facility has tremendous peaks and valleys in compressed air demand. Our audit using flow meters and pressure transducers with calibrated gauges has proven this. Our Phase 1 audit recommends the use of storage tanks and flow meters to reduce air consumption while stabilizing pressure. Implementing the recommendations in Phase 1 will provide estimated annual savings of \$262,553 with an estimated payback of 10 months and an internal rate of return of 72%. Once completed with Phase 1, we can embark upon Phases 2 and 3 of the audit (not outlined in this article). The Phase 2 audit will examine ways to reduce the significant purge air of the heatless desiccant air dryers (estimated annual energy cost of \$312,380). The Phase 3 audit will examine ways to eliminate the significant levels of compressed air leaks in the West Facility (estimated annual energy cost of \\$487,076).

The Phase 1 audit and the preliminary findings for Phases 2 and 3 demonstrate that this automotive assembly facility can significantly reduce the energy costs related to the compressed air system per vehicle manufactured.