The old windmill still pumps water for the cattle, here by the corrals and loading chute. Windmills are far from obsolete, and this very model continues in production, for pumping water, or, with the addition of an appropriate generator, as a potential electrical power source.
Windmills are particularly suited to bringing water to the surface in places far from the nearest powerlines. By adjusting the stroke, even moderate winds can be used to raise water from deep wells, albeit slowly. And, when the pump runs for hours on end, enough water can be raised to keep quite a few cows from thirst. Not bad, considering that one cow can drink about 30 gallons per day.