How is "superheat" defined in relation to steam?

Superheat is defined as the process of raising the temperature of steam above its saturation point. This occurs after the steam has been generated, and it's vital for improving energy efficiency in steam systems. By increasing the temperature of the steam beyond its saturation point, the steam can carry more energy, resulting in better performance in turbines and other equipment that utilize steam.

Additionally, superheated steam can help to prevent condensation within the steam lines, which may lead to issues such as water hammer or equipment damage. This concept is essential in applications like power generation, where maximizing the thermal efficiency of the cycle is crucial.

In contrast, the other options do not accurately describe superheat. Converting water into steam refers to the phase change process, cooling steam back to water describes condensation, and mixing steam with hot water does not pertain to the concept of superheating at all. Understanding superheat is fundamental in power engineering to optimize steam properties and enhance system performance.