Building AI Infrastructure Inside a Mountain | HPC at HRT

The Leftdal Mine Datacenter in Norway represents a significant shift in high-performance computing (HPC) infrastructure, repurposing a former olivine mine into a massive, sustainable facility for AI research. This billion-dollar investment leverages a unique fjord-based cooling system that utilizes the siphon effect to transport cold seawater to heat exchangers, achieving a power usage effectiveness (PUE) below 1.1. The facility operates at extreme densities, currently reaching 130kW per rack with plans to scale further using direct liquid-cooled NVIDIA GPUs and specialized storage arrays. Beyond technical specifications, the project emphasizes environmental circularity by planning to reuse heated byproduct water for a nearby salmon hatchery. This collaboration between engineers and hardware integrators pushes the limits of existing technology, focusing on 800-volt DC distribution and high-speed networking to maximize GPU efficiency for large-scale model processing.