Note the dates those coal network electrifications took place - they would have all been approved during the Bjelke-Petersen years. Not to cast political assertions one way or another, but in the years that followed, attitudes towards the regional rail network certainly shifted.
Outside new passenger lines in the greater SEQ region, I donāt think anyone has seriously put forward a proposal for further electrification since then.
In fact, lines have been de-sparked over the years. Blackwater - Emerald (i.e. beyond the Aurizon network) has the infrastructure, but is not powered anymore. QR itself retains no electric locomotives that could be used for shunting or hauling the carriage-hauled services.
The incentive for Aurizon to spark any of its other systems (Moura, Newlands etc.) seems limited.
The case could be made for the North Coast Line north of Rockhampton I think, but if I were to choose between re-alignments to bring the speed up to a minimum of 100kph freight running outside population centres (possibly Tilt 120/140/160 if workable) and electrification, Iād probably take the former in the first instance. As Iāve maintained in other threads, the sub-60kph average speed between Townsville and Cairns is diabolical.
Although, you ask the residents of Rockhampton if theyād like overhead lines running down Denison St as part of the train line, and you might get some colourful answers.
For other systems:
The challenge for the Main Line/West Moreton System is that it will become, at least in part, a component of inland rail in future (maybe), which is not intended to be electrified. The current Toowoomba range railway has an average speed of about 25kph (see: 1hr 50-ish minutes from Toowoomba to Helidon) and the tunnels are far too short for wires, and some are heritage listed. It would be an enormous challenge to spark the current range railway, even in the parts not captured by Inland Rail (not to mention the line speed makes it a poor investment overall, better to focus on a new corridor).
Traffic on the southern/south-west/western lines and branches probably does not justify the expense (so thatās Warwick/Stanthorpe/Goondiwindi/Thallon/Charleville). Toowoomba - Miles maybe because of the volume of coal traffic (6x trains daily typically). The Millmerran branch (currently open to Brookstead grain silos) will become, in large part, part of Inland Rail under current plans. Most other branches have already closed (Glenmorgan as far as Meandarra might be all thatās open now, but some are only listed as āout of useā rather than fully closed).
Traffic on the central west line beyond Aurizon territory (Blackwater - Longreach/Winton) almost certainly doesnāt justify the effort or expense.
Iād be dubious about the Mt Isa line as well.
Iām not sure the Kuranda line is suitable for electrification. The number of small tunnels and other geographical limitations would necessitate an enormous cost. Iām all for sustainability projects though, so perhaps hydrogen or battery locomotives might be suitable for this tourist line. As far as I am aware, no freight goes north of Cairns. Which in itself is a shame, because a perfectly good station at Mareeba, a hub for agriculture on the Atherton Tablelands, is slowly falling apart.