Yes, a ceiling fan running at a slower speed consumes less power or electricity units compared to when it is running at a higher speed. The power consumption of a fan is directly related to the speed at which it operates.
Ceiling fans typically have multiple speed settings, and the power consumption is highest at the highest speed setting. As you lower the speed of the fan, the power consumption decreases. This is because the energy required to rotate the fan blades and circulate the air decreases as the speed decreases.
It's important to note that while running a fan at a slower speed can help reduce power consumption, the actual amount of energy saved may vary depending on factors such as the fan's motor efficiency and design. However, in general, running a ceiling fan at a lower speed is more energy-efficient than running it at higher speeds.