▁. ▁Wind ▁tur b ines ▁must ▁be ▁protected ▁from ▁ice ▁accum ulation . ▁It ▁can ▁make ▁an em ometer ▁read ings ▁in ac cur ate ▁and ▁which , ▁in ▁certain ▁tur bine ▁control ▁designs , ▁can ▁cause ▁high ▁structure ▁loads ▁and ▁damage . ▁Some ▁tur bine ▁manufact ur ers ▁offer ▁low - temper ature ▁packages ▁at ▁a ▁few ▁percent ▁extra ▁cost , ▁which ▁include ▁internal ▁he aters , ▁different ▁lub ric ants , ▁and ▁different ▁allo ys ▁for ▁struct ural ▁elements . ▁If ▁the ▁low - temper ature ▁interval ▁is ▁combined ▁with ▁a ▁low - wind ▁condition , ▁the ▁wind ▁tur bine ▁will ▁require ▁an ▁external ▁supply ▁of ▁power , ▁equivalent ▁to ▁a ▁few ▁percent ▁of ▁its ▁r ated ▁power , ▁for ▁internal ▁he ating . ▁For ▁example , ▁the ▁St . ▁Leon ▁Wind ▁Farm ▁in ▁Man it oba , ▁Canada , ▁has ▁a ▁total ▁rating ▁of ▁ 9 9   MW ▁and ▁is ▁estimated ▁to ▁need ▁up ▁to ▁ 3   MW ▁( around ▁ 3 % ▁of ▁capacity ) ▁of ▁station ▁service ▁power ▁a ▁few ▁days ▁a ▁year ▁for ▁temper atures ▁down ▁to ▁. ▁This ▁factor ▁affect s ▁the ▁econom ics ▁of ▁wind ▁tur bine ▁operation ▁in ▁cold ▁clim ates . ▁ ▁See ▁also ▁▁ ▁Br ush less ▁w ound - rot or ▁doub ly ▁fed ▁electric ▁machine ▁ ▁Flo ating ▁wind ▁tur bine ▁ ▁Vert ical - axis ▁wind ▁tur bine ▁ ▁Wind - t urb ine ▁aer od ynam ics ▁ ▁Co pper ▁in ▁renew able ▁energy , ▁section