By this, unnecessary frequent swiveling of the nacelle is avoided and also {HEAD ~ a large amount} of {TAIL ~ electricity} for swiveling the nacelle is saved 
of
By this , unnecessary frequent swiveling of the nacelle is avoided and also { HEAD ~ a large amount } of { TAIL ~ electricity } for swiveling the nacelle is saved
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH