A Case Study on Energy Optimization in HVAC Systems

Background

With the growing demand for precision manufacturing and clean production, the scale and number of cleanrooms continue to expand. As an energy-intensive industry, the pharmaceutical sector is increasingly focused on addressing energy consumption issues during operations. Balancing compliance with GMP and other regulatory requirements while achieving energy savings and reducing operating costs has become a key challenge for the industry.

This case study focuses on the renovation project of a large-capacity production workshop for vitamin-based formulations at a biotechnology company. The project involves upgrading and optimizing two existing facilities——the office and quality control building and the integrated formulation workshop.

Energy-Saving Design Strategy

For the traditional single-return air system, we introduced the "fresh air pre-treatment" technology to optimize the thermal and humidity treatment process of the modular air handling units (AHUs):

• Conventional approach: Return air mixed with fresh air → Dehumidification and cooling → Reheating → Air supply

• Optimized approach: Fresh air pre-cooling → Mixed with return air → Further cooling (dehumidification) → (Reheating) → Air supply

This optimized strategy reduces the overall thermal and humidity load by pre-treating fresh air in advance, effectively lowering the energy required for subsequent reheating.

Energy-Saving Results

Theoretical calculations indicate that adding a fresh air pre-cooling section to modular AHUs, where space permits in the machine room, can reduce overall cooling loads by approximately 20%. Additionally, adopting independent fresh air treatment technology can achieve similar results, further enhancing system efficiency.