The current upgrading of the national electricity grid is expected to cost $50 billion over 3 to 4 years – far more than the much-debated National Broadband Network, which is estimated at $36.5 billion. Yet there is very little discussion of the need for that expenditure.
The reason for the upgrade is the forecast growth in demand for electricity. But, in fact, demand is falling. (See Why Lower Demand Means Higher Electricity Prices.)
The way in which the electricity network is being upgraded is designed to distribute more power from large central power stations. Yet no more large central power stations are planned for at least a decade.
New electricity supply will come from decentralised renewables – solar panels on rooftops and relatively small wind farms and solar parks. Much of this genearting capacity will be located near the end-user. Meaning that there is little need for an expanded "poles and wires" network.
On the other hand, renewables are most effective when power can be drawn from a variety of location where the wind is blowing or the sun shining. This needs a national – or even international – high capacity trunk system, which would probablly be DC rather than AC. But this is not what is being built.