TACC Lonestar6 immersion cooling

Project brief

What is publicly known

Status: operating. GRC reported in January 2022 that the Texas Advanced Computing Center had deployed 280 kilowatts of ICEraQ Series 10 single-phase immersion capacity for part of the Lonestar6 supercomputer. The system cools Dell C6525 servers using AMD EPYC processors.

This is a named operator, system, server platform, location, and installed load, which is materially stronger than an order or memorandum. The public evidence is still a supplier case study. We have not been given a Texas Advanced Computing Center acceptance report, operating log, or independent energy audit.

The cooling design places servers in a dielectric liquid that remains in one phase. Heat moves from the bath through a heat exchanger to facility water. GRC says removing server fans reduced server power by about ten percent and that cooling achieved a partial power usage effectiveness of 1.02.

Partial power usage effectiveness describes only the measured subsystem, not every electrical load in the building. Those values are useful directional evidence, but they need a stated test boundary, weather period, and workload before they can support a facility-wide comparison. Unknowns include water supply and return temperatures, tank count, utilization, maintenance history, fluid testing, failure events, and whether the original 280 kilowatts remain in service.

The record would become stronger with operator-published performance data, a recent operating update, measured energy over a full season, or details on server service and fluid condition after several years. Evidence of expansion would justify a higher capacity. Evidence that Lonestar6 has been decommissioned or the tanks removed would change the status to retired, a state the current schema does not yet express.

Until then, operating is the best-supported label, with supplier-reported performance clearly qualified.

Status is labeled from public evidence. Supplier orders, MoUs, pilots, projects under delivery, and operating sites are not counted as equivalent.