Scenario B (earth-radiation cooling)
Scenario B is based upon not only obtaining an adequate supply for cooling, but injecting the fully-heated cooling water directly into an underground mine. This cooling cycle is a “closed loop”, in that no cooling tower is employed and little waste heat is discharged at the plant site. Instead, heat is dissipated by radiation from water within the underground mines to the rocks surrounding and above the mine. There is no cooling tower, limited steam evolution, and little evaporative concentration of cooling water. Also, loss of heat from the plant process is accomplished by conduction only, not by loss of the heat of vaporization as for cooling towers. Therefore, the water needs are significantly greater in quantity than for Scenario A. Feasibility will be based on the availability of water in the mine-water reservoir; the practicality of cooling by earth radiation; and environmental factors.