Energy recovery systems capture waste heat, pressure differentials, and other energy byproducts from semiconductor fab operations for reuse, reducing total facility energy consumption by 10-30%.

Recovery Methods

Heat exchangers capture waste heat from process cooling water, exhaust air, and chiller condensers to preheat incoming fresh air, DI water, or chemical baths. Heat pumps upgrade low-grade waste heat to useful temperatures for building heating or process applications. Exhaust heat recovery uses heat wheels or run-around coils to transfer energy from fab exhaust air (maintained at 20-22°C, 40-45% RH) to incoming makeup air. Chiller waste heat: Chillers reject 1.2-1.5× the cooling load as heat, which can supply building heating and DI water preheating.

Fab Energy Breakdown

• HVAC/Cleanroom: 40-50% of total fab energy (largest consumer) • Process Tools: 30-40% (plasma, heating, pumping) • DI Water/Chemical Systems: 5-10% • Lighting/IT/Other: 5-10%

Economic Impact

A modern 300mm fab consumes 50-100 MW of electrical power. At $0.08/kWh, annual energy cost is $35-70 million. A 20% energy recovery saves $7-14 million per year. Heat recovery systems typically pay back in 2-4 years.