The issue with heavy freight is the Wellington trains use 1.5kv DC, and the main trunk and Auckland metro island 25kv AC. So a locomotive capable of running from Auckland to Wellington would need to accept two very different voltages.

A problem made worse by the fact our rail gauge can't take much weight, so adding this tech to a diesel loco would be very difficult.

[–] Dave 1 points 1 year ago (1 children)

Yeah, I've heard this issue before. Is it too much to ask that we think of these things before substantial investment? Wellington has just replaced a significant amount of their overhead lines.

[–] Ilovethebomb 2 points 1 year ago (1 children)

There's a big difference between renewing the existing lines, and completely changing the system. You're increasing the operating voltage more than 10x, the insulators and clearance required would be huge. You'd have to raise bridges, lower the floors of tunnels, completely renew the poles, lines, and insulators, all while keeping the lines running during the day.

Not only that, but this would require massive alterations to the rolling stock once the change happens, which would have to be done all at once after you switch voltages.

I understand the sentiment, but it would be an absolute boondoggle.

[–] Dave 2 points 1 year ago

Oh yes, of course it would be a massive job. But I'm just saying, maybe someone should have a plan. As far as I can tell, no one has a unified plan for what we want our rail network to look like in 50 years.