Future of Green Computing: Under What Conditions Can Underwater Data Centers Deliver a Net Environmental Benefit

Data centres are increasingly important to global energy and environmental policy, with global electricity consumption projected to rise sharply as artificial intelligence workloads expand (IEA, 2024, 2025). Conventional cooling can account for up to 40% of data-centre energy use and consume substantial freshwater, particularly in water-stressed regions (U.S. Department of Energy, 2025; Nicoletti et al., 2025; Ceres, 2025). Underwater data centres offer an alternative by using seawater as a heat sink. This review examines evidence from Microsoft’s Project Natick and emerging developments in China and South Korea to assess whether underwater facilities can provide net environmental benefits compared with land-based data centres. Early evidence indicates potential benefits in energy efficiency, freshwater use and land requirements, but these findings remain limited by small-scale deployments and short operational periods. Marine ecological impacts are also insufficiently understood. The review therefore proposes an integrated framework assessing energy, freshwater, land use, reliability and marine ecological impacts to evaluate the technology’s overall environmental sustainability.