What are the main parts of a power plant?

The main parts of a power plant typically include components that directly contribute to the generation of electricity. A turbine and generator represent a critical pair in this process; the turbine converts mechanical energy (often derived from steam, gas, or water) into rotational energy, while the generator converts that rotational energy into electrical energy.

The other options suggest components that have specific functions but do not encompass the primary elements of a typical power plant operation. An engine and propeller are more related to aviation or marine applications rather than stationary power generation. A boiler and condenser are parts of certain types of power plants, specifically steam power plants, but do not cover all types of plants (like gas, hydro, or nuclear). Similarly, a reactor and coolant pertain specifically to nuclear power plants and are not representative of the general power generation process across various types of plants.

Thus, the pairing of the turbine and generator effectively captures the essence of how power plants function, making it the most appropriate choice for identifying essential components responsible for electricity generation.