This invention is a self-powered wireless current transformer sensor and transmitter for switchboard energy management applications. It measures current from a monitored conductor and wirelessly transmits metering or load-management data without auxiliary power, wired communications or batteries. The device harvests energy from the CT secondary or electromagnetic field, stores and regulates the harvested power, wakes periodically, samples current, calculates load information and transmits data to an EV charger, inverter, gateway, cloud platform or home energy controller.