The West Wind seems to be very powerful for Shelley, in Ode to the West Wind, as he asserts that the West Wind can destroy as well as preserve anything. The West Wind can carry a leaf to new places, and push giant oceanic waves and even clouds along with it. There's something else to this power. The West Wind, which takes dead leaves along with it that ultimately helps grow new plants, and has the power of regeneration, in this way. The poet calls West Wind to fasten this kind of a rebirth for him also.
The poet requests West Wind to give him this magnificent power, make him a companion so that when he moves along with the wind, his thoughts also reach many new places and thus awaken young minds. Now, he cannot do this himself as he feels shackled and bound on Earth.