Open Compute Project

OCP CE - CDU _ Coolant Distribution Unit Project Call (Oct 28, 2025)

The Open Compute Project convened its first Coolant Distribution Unit (CDU) workstream call, outlining a three‑phase deliverable: a high‑level white paper, a detailed performance specification, and a commissioning guide. Co‑lead John Minaj, joined by representatives from Nvidia, Google, and a CDU‑producing startup, emphasized the need for a unified industry reference that clarifies component types, design criteria, and testing methodologies. Participants highlighted gaps in current documentation, noting that many data‑center planners struggle to differentiate CDU architectures—liquid‑to‑liquid, liquid‑to‑air, rack‑mount, etc.—and to understand key metrics such as approach temperature. Nvidia’s Praep Shahi and Google’s Husam Kabani pledged existing internal specifications and qualification procedures to inform the OCP drafts, while Jack Kar stressed transparency to prevent “smoke and mirrors” in performance ratings. The discussion also introduced the Ashray 127 testing methodology as a benchmark for rating CDUs, and underscored the broader OCP Advanced Cooling Facilities goal: enable higher compute density, improve energy efficiency, and unlock heat‑reuse opportunities. By standardizing metrics like approach temperature and defining commissioning steps, the workstream aims to reduce vendor‑to‑vendor variance and simplify procurement decisions. If successful, the white paper and subsequent specifications will give data‑center operators a clear, vendor‑agnostic framework for selecting CDUs, accelerating liquid‑cooling adoption and supporting sustainability targets across the industry.