Most CDUs are rated at a 4°C approach temperature, but that gap between facility water and rack supply has a direct bearing on how often chillers need to run. Reducing it to 2°C can add hours of free cooling and cut the energy needed to keep racks within their thermal limits. The difference becomes particularly important with AI chip requirements changing and operators looking to raise supply temperatures without placing more strain on existing cooling infrastructure. Using modeled cooling data, this session examines what those two degrees mean across a full year of operation, from chiller runtime to energy costs, and how coordinated cooling loop control and access to alternative water sources could make year-round free cooling possible. This tech showcase will discuss:
- How reducing CDU approach temperature to 2°C adds free-cooling hours throughout the year
- What fewer hours of mechanical chilling mean for power consumption and operating costs
- Raising supply temperatures as chip requirements change without overloading existing chillers
- How different water sources could support year-round free cooling with mechanical systems in reserve
