Which plant does not utilize steam in its electrical generation process?

The selection of hydroelectric as the correct answer is valid because this type of power generation relies primarily on the kinetic energy of flowing water to produce electricity. In hydroelectric plants, water is diverted from a river or reservoir to turn a turbine, which activates a generator to produce electricity. This process does not involve the use of steam at any stage.

In contrast, geothermal plants harness heat from the Earth's crust to generate steam, which then drives turbines. Solar thermal plants employ mirrors to concentrate sunlight to produce heat, creating steam to drive turbines as well. Biomass facilities burn organic material to generate heat, which also creates steam for power generation. Therefore, hydroelectric stands out as the only method that does not involve steam in its electricity generation process.