Ultrasonic anemometers measure the horizontal wind speed and direction as well as the acoustic virtual temperature. However, because of their high power consumption, a connection to mains power supply is required and their application at self-contained, solar-powered measurement systems is not feasible. Ultrasonics offer excellent performance ratings at well-powered measuring stations. Ultrasonics are mostly applied for wind farm monitoring, on wind turbines and on offshore projects. Most ultrasonic anemometers can be fitted with electronically regulated heating.