What is Dry cooling?
Dry cooling sends warm facility water or glycol through outdoor finned coils while fans move ambient air across them. Heat passes to the air without routine evaporation, so the main heat-rejection path does not consume process water. The architecture fits warm-water liquid cooling and water-constrained sites, especially where the required supply temperature remains above hot-day ambient conditions. Its limit is dry-bulb temperature: as outside air warms, the temperature difference shrinks, available capacity falls, and fan power rises. The facility needs roof or yard area, structural support, electrical feeds, variable-speed controls, piping, expansion and air removal, freeze protection, drainage, coil cleaning, noise review, and a plan for the hottest weather. Glycol protects against freezing but changes heat transfer and pumping duty. Ask for capacity, outlet temperature, pressure drop, and fan power at the site's summer design temperature and altitude, not only a nominal rating. Then test one-fan, one-bank, and power-failure cases. Procurement should define coil material, corrosion protection, fouling allowance, sound limits, service clearances, controls, and winter operation. Some designs add adiabatic spray or another backup on peak days; if so, “dry” no longer means zero water in all conditions. Compare annual fan energy, land, noise, and backup-plant cost with evaporative or compressor-based alternatives.