In my article arguing that electricity from solar PV (and wind) could soon be too cheap to meter, I didn’t mention transmission networks. That was for space reasons.
The case for public investment is actually stronger for transmission than for generation. Electricity transmission lines have the same cost structure as renewables (low operational cost and long lives), if anything more so, meaning that the cost of transmission depends primarily on the need to secure a return to the capital invested.
More than this, the electricity grid as a whole is a complex network in which valuing the services of any individual component is just about impossible. That in turn means that relying on markets to make optimal investment decisions is untenable.
For these reasons, the electricity transmission network should never have been privatised. I’ve been arguing for renationalisation for years.
Amazingly, in the new low interest environment, this idea seems to be gaining traction, at least as regards new investment. Labor has proposed a $20 billion public investment. The government hasn’t gone that far, but is seeking to use its own borrowing capacity to provide low cost finance for transmission investment ( a half-baked compromise, but better than nothing).