With rotating roofs and self - adjusting sails, windmills reached their zenith by the late 19th century, when it was estimated that European mills were churning out some 1,500 megawatts of power.
Dengan atap berputar dan daun kincir yang dapat menyesuaikan sendiri, kincir angin mencapai puncak kejayaannya di pengujung abad 19, dan diperkirakan bahwa seluruh kincir angin di Eropa menghasilkan sekitar 1.500 megawatt tenaga.