The construction of a new generation of Cook Strait ferries is a step nearer, with KiwiRail beginning the process of settling on a shipyard to build two new ships.
KiwiRail says that the $400million earmarked for new ferries in the Government's Budget 2020 – part of its $1.2bn rail spendup (and on top of last year's $1bn) – has allowed it to go out to international tender to have the ships built.
KiwiRail's iReX Project will see the replacement of the existing three-ferry fleet with two new, much larger ships – scheduled to go into service in 2024 and 2025.
The new ferries will be technologically advanced, have significantly lower CO2 emissions, a greater carrying capacity and will provide "an enhanced visitor experience," KiwiRail group chief executive Greg Miller says.
They will each be 40 metres longer and five metres wider – and together the pair will be able to carry "almost double the number of trucks and other vehicles," 300% more rail wagons and twice as many passengers as the current three-ship fleet.
KiwiRail reckons they are projected to meet the expected freight and passenger growth over the next 30 years.
The high-tech ships will have the latest propulsion systems and will be capable of running on battery power at times, KiwiRail says. They will also be futureproofed so they could switch to alternative fuels.
The new ferries represent "a once-in-a-generation opportunity to transform the Cook Strait crossing," says Miller. 
By the time they're delivered, it will be more than 25 years since Interislander had a brand-new, purposebuilt ferry. 
Currently, KiwiRail's three ferries carry 800,000 passengers and up to $14bn worth of road and rail freight annually.
Miller says that the new ferries and associated port infrastructure upgrades "will provide greater resilience for this crucial link that unites our country and will serve NZ for the next generation and beyond."