The paper deals with the parametric simulation for design and optimization purposes of a heat integrated geothermal desalination plant for domestic use of fresh water, focusing on the appealing multi-effect distillation (MED) process to handle water shortage in remote locations with low-temperature geothermal potential. Several innovations are introduced in the simulation, such as a loop for the geothermal heat transfer, the use of desalinated water in the geothermal well, and the introduction of a heat integration train to preheat seawater. Heat integration helps manage oscillations in the plant operating conditions caused by inevitable seasonal climate variations, and the parametric simulation enables early reliable economic assessments on capital investment, and the forecast of practical benefits. Despite the generality of the proposed approach, for the sake of clarity and quantitative analyses, the study is contextualized to the water shortage in Isola di Pantelleria, and the plant layout is optimized accounting for the flexible water supply of popular tourist destinations. (C) 2013 Elsevier B.V. All rights reserved.