Ancillary services refer to additional support services that enhance the primary offerings of a business or organization. In healthcare, for example, these services can include physical therapy, radiology, and laboratory testing, which help improve patient care and outcomes. They are essential for providing comprehensive solutions to meet the needs of clients or patients. In the energy sector, ancillary services help maintain the reliability and stability of the electric grid. These services include frequency regulation, voltage control, and spinning reserves, which ensure that electricity supply meets demand. They play a crucial role in preventing outages and ensuring a consistent power supply.