Portable power management systems must optimise power interfacing, storage and
routing, to meet application specific functionality requirements. Two key aspects are reliability
and efficiency. For reliable operation, it is required that powering on/off the system must occur
in a planned manner. For efficient operation, it is desired that the system is powered for an
optimal amount of time. maximizing its useful operational outcome per unit of energy consumed.
This can be achieved by optimizing energy usage based on the anticipated energy income and
power demand of duty-cycled power consumers. Both battery and supercapacitor storage can be
employed to meet energy and power density demand, on both sides, and to enable fast transition
from cold-starting to active power management. A simplified model is used to calculate the
reliability of a simple solar-powered microsystem. The modelling of dynamically configurable
interfacing and storage may enable a new generation of power management, providing reliable
power from irregular and small energy sources.