Why are autotransformers considered economically advantageous?

Autotransformers are considered economically advantageous primarily because they are cheaper than two-coil transformers. This cost efficiency arises from their design, which utilizes a single winding that serves both as the primary and secondary winding, rather than the two separate windings found in traditional transformers. This simplifies the construction and reduces material costs, making autotransformers a more economical option for certain applications where voltage transformation is required.

The design of an autotransformer allows it to operate more efficiently in scenarios where only a small voltage change is necessary, further emphasizing their cost-effectiveness. In contrast to options that suggest heavier construction, more windings, or greater voltage output, the inherent simplicity and reduced material requirement of the autotransformer's design are what contribute to its lower cost. Thus, their economic advantage is rooted in their unique design rather than in increased complexity or performance metrics.