Energy Harvesting Models and Techniques

Wireless sensor networks (WSNs) has gain popularity due to their wide range of applications in almost all walks of life including industry controls, environmental monitoring, health, transportation, military, civil infrastructure, science, security and more. Wireless sensor nodes are cheap and tiny in size therefore its deployment is easier. They perform well in harsh environments where human intervention is almost difficult or not possible. However, wireless sensor networks are resource constraints and its power supply has been a big challenge to keep the sensor nodes functional for a longer period. Advancement in low power electronics helped a lot but the use and maintenance of conventional batteries with a limited life span cannot address the power supply problem effectively in a long run. Therefore, harvesting energy from ambient environment is an effective alternative both in terms of power and cost, which can help sensor networks to live longer. This chapter mainly focuses on different possible energy sources available in ambient environment and current technological mechanism to harvest energy for WSNs.