Modeling freshwater use for direct lithium extraction from geothermal brines in the Salton Sea
Year: 2026
Type: article
Abstract: Global lithium demand is projected to more than double by 2035, to about 715 kt per year (3.8 Mt lithium carbonate equivalent (LCE) per year) under the International Energy Agency Stated Policies Scenario, intensifying the need for new, sustainable extraction routes. Direct lithium extraction (DLE) from geothermal brines is of particular interest because co-location with closed-loop geothermal operations avoids the large land footprint of evaporation ponds and the carbon intensity of hard-rock mining. The Salton Sea Known Geothermal Resource Area (SS-KGRA) hosts geothermal plants with co-located pilot-scale DLE facilities and is one of the most advanced regions for geothermal lithium extraction. Though these operations are expected to reduce land and carbon intensity, they require freshwater inputs across multiple unit operations; this demand has been reported only as facility-wide aggregates, without process-level resolution, even though the SS-KGRA lies in an arid region where water supply is largely committed to agriculture. Existing estimates do not track the internal fate of process water, which determines the net volume drawn from external sources. Herein, we present LiHydroSim, a process-based model that translates publicly available process descriptions into a facility-level freshwater balance through a three-layer architecture separating gross unit-operation demand, internal recovery, and net external supply. Applied to a representative adsorption-based facility processing 7000 gallons per minute of geothermal brine, the model estimates net external freshwater demand of 1719 acre-feet per year (152 m 3 t − 1 LCE; 0.12 AF/t LCE), below the 189–355 m 3 t − 1 LCE (0.15–0.29 AF/t LCE) reported by Salton Sea developers, consistent with auxiliary demands outside the process boundary. The eluant for lithium elution dominates the water balance, accounting for 92% of gross internal process-water demand, while internal recycling offsets roughly one third of that gross demand. Total demand depends mainly on eluant volume: across two patent-specified operating modes, it ranges from 870 to 1719 acre-feet per year.
Source: Environmental Research Letters
Authors: Lakshani Gunawardhana, Margaret M Busse
Institution: Pennsylvania State University
Language: English
Subfield: Metals and Alloys
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,045
OpenAlex ID: W7220965765