Energy supply is a major challenge for sensor network sustainability. A feasible alternative for enabling long term self-sustained deployments is to supplement or replace the battery supplies with environmentally harvested resources, such as solar power in outdoor environments. However, there are several changes required in system design to support harvested energy such as the capability to learn the environmental energy levels in addition to residual battery. Further, the environmental energy opportunity is significantly variable across space and time. The required taskload should be allocated among multiple nodes as per their energy availabilities to extract maximum performance from the system.