Final answer:
Larger vehicles, such as helicopters and experimental energy recovery buses, utilize rotors and flywheels to store substantial rotational kinetic energy used for flight and efficient energy management, respectively.
Step-by-step explanation:
The type of rotor usually used on larger vehicles, such as helicopters and buses with kinetic energy recovery systems, is designed to harness and store significant amounts of rotational kinetic energy. For helicopters, which require a substantial amount of energy to remain airborne, this energy is stored in the main lift blades and is critical for both takeoff and sustaining flight. The engines alone are not powerful enough to both lift the helicopter and impart significant rotational energy to the blades. Hence, special measures are taken to ensure the blades have sufficient rotational kinetic energy before takeoff.
Additionally, some experimental buses are equipped with a large flywheel that serves to store rotational kinetic energy. This technology allows the bus to convert gravitational potential energy into rotational kinetic energy (KErot) as it descends a hill, as well as convert translational kinetic energy into KErot when the bus stops. Later, this stored energy can be used for various purposes such as accelerating, climbing hills, or reducing the impact of friction on the bus's speed.
In the context of wind turbines, particularly for marine environments, it is stated that large land-based turbines are impractical, meaning smaller-scale rotors would be used, likely generating on the order of hundreds of kilowatts each.