Solar Energy Harvesting and Power Management for Self Powered Wireless Temperature Sensor

Now a day’s temperature monitoring of buildings is essential for controlling the ambient temperature for human safety, comfort and reliability. Wireless sensors are best choices for such temperature monitoring. But greatest challenge faced by wireless sensor networks is power. When a sensor is depleted of power, it can not fulfill its role unless and until the source of power is replenished. Therefore, it is considered that the smartness of a wireless sensor expires when its battery power is finished. In temperature monitoring applications, sensors are supposed to operate for much longer durations (such as years or decades) after they are installed on the field. In such cases batteries are hard (or impossible) to replace or recharge after they are discharged. To overcome this, system has been implemented which scavenges energy from ambient solar energy and stores it in super-capacitor for further use. Harvested energy is made sufficient for sensor operation using power management technique and supercapacitor lifetime is calculated for estimating lifetime of sensor once super capacitor is fully charged.