Energy Harvesting wireless sensor network(EH-WSN) is a kind of WSN that

uses rechargeable power supply instead of using traditional battery.

In traditional WSN, the energy sources is limited. When the power source of

node nish, it can not continue to work unless it is recharged again. So the

eort was to design energy-ecient network protocols to maximize the lifetime

of WSN by minimizing energy usage.if we can have access to unlimited power, we can have innite

lifetime in network. This unlimited power can be provide by environment such

as light, vibration and heat. Then stores the harvested energy in a storage

device. When the device uses energy harvested instead of battery, the residual

energy is no more an useful quantity to preserve. In EH-WSN, if the rate of

harvesting power is lesser than the power used by the node, the sensor node

should go to sleep to charge up.