U.S. Department of Energy - Energy Efficiency and Renewable Energy

Federal Energy Management Program

New and Underutilized Technology: Evaporative Pre-Cooling Systems

The following information outlines key deployment considerations for evaporated pre-cooling systems within the Federal sector.


Evaporative pre-cooling systems install ahead of the condenser to lower the condenser pressure. These systems can also work with an economizer. Evaporative pre-cooling reduces the requirement for energy intensive DX cooling.


Evaporative pre-cooling systems are applicable in most building categories.

Climate and Regional Considerations

Evaporative pre-cooling systems are well suited in dry climates.

Key Factors for Deployment

Water usage needs to be taken into account in evaporative pre-cooling system deployment. Several variations of this concept are available.

Ranking Criteria

Federal energy savings, cost-effectiveness, and probability of success are ranked 0-5 with 0 representing the lowest ranking and 5 representing the highest ranking. The weighted score is ranked 0-100 with 0 representing the lowest ranking and 100 representing the highest ranking.

Federal Energy Savings Cost Effectiveness Probability of Success Weighted Score
0.3 3.0 3.8 36