Population growth, urbanisation and climate change necessitate a paradigm shift in the design and operations of the classical electrical power grid. The original ideas underpinning the first AC grids of the late 19th century still define the present grid, which consists of large power sources at a few distinct locations supplying through the high voltage transmission grid a large, geographically distributed low voltage consumer base. Much of this paradigm is being questioned at present because a) Renewable power sources come with a far lower power intensity per square meter of installation; b) Renewable power sources suffer from uncontrollable temporal variations unknown in classical power generation; c) In well-established grids, peak-to-base power consumption is increasing, making the transmission grid which caters by necessity for peak demand an economically very unattractive proposition. At the same time, new technologies provide opportunities a) smart metering, but more generally intelligent, interconnected, infrastructure or an internet-of-things for the grid, is totally feasible; b) transport is becoming more electrified, with electric vehicles entering the light vehicle market; c) electrical energy storage, or non-fossil fuel energy storage at scale is becoming an economically realistic proposition. In particular these new technologies allow us to reconsider what the last mile in the grid may look like when demand and supply are coordinated through a power matching strategy that respects the physical infrastructure's operational limits. We argue the economic need to consider such approaches in the distribution grid, based on grid usage considerations. Distributed, receding horizon optimized distribution of power to satisfy consumers' energy needs, minimize their energy bills, whilst maximising the utility of renewables, and the grid itself is a realistic option that may change the way we use electrical power and build and exploit distribution networks. Much of our experience, and the data used in the presentation, are Australia specific. Nevertheless, we will consider scenarios applicable to both high population density urban living as well as semi-rural, and rural circumstances, inclusive of some remarks around the management of micro-grids that may evolve as demand requires. The talk will conclude with some observations about the socio-economic and political dimensions of a grid infrastructure supplied by renewable power sources. Non-trivial national regulatory reform is required in Australia, but such reform is insignificant when compared with the trans-national and trans-regional cooperation that is essential to achieve equitable world-wide access to renewable power.
