What are the disadvantages of dynamos?

Dynamos can have several disadvantages, including limited efficiency and power output, particularly at low speeds, which can hinder their performance in certain applications. They also require maintenance due to wear and tear on components like brushes and commutators, which can lead to increased operational costs. Additionally, dynamos are generally bulkier and heavier compared to modern alternatives like alternators, making them less suitable for compact applications. Finally, they produce direct current (DC), which may not be compatible with all systems and requires additional components for conversion if AC is needed.