KiwiRail has received nearly 4000 emails asking that it retain its electric locomotive fleet. This comes after its announcement in March that the state-owned enterprise is considering replacing its electric locomotives with new diesel engines, as a means of saving money.

A rally against the proposal was also held outside KiwiRail's Auckland office on 22 April. It was lead by the Green Party and the Rail and Maritime Transport Union.

Since then, Green transport spokesperson Julie Anne Genter has met with KiwiRail Chief Executive Peter Reidy to share public concerns, and in the process shed some light on KiwiRail's considerations.

Genter says while KiwiRail has been costing its options, it has found it would in fact be cheaper to refurbish the current electric fleet than to purchase new diesel locomotives. However, the sticking point comes in the form of timing.


"If they ordered new diesel locomotives now, they could get them up and running on the line quite quickly, whereas if they refurbished the existing electrics it could take a couple of years," she says.

"In the very short term it might makes sense for them to buy more diesel locomotives, but that's only really if you aren't considering the reality of climate change and our need to be investing for the long term."

In relation to the carbon emissions of electric rail operations relative to diesel, Genter points to studies of situations in the United Kingdom and Canada. These concluded that electric is far superior to diesel in terms of efficiency and sustainability.

Although electric locomotives do not give off any emissions themselves, their life cycle carbon footprint is determined by how the electricity they use is generated. Given this, Genter suggests electrics would particularly suit New Zealand, considering that 79.9 percent of the country's electricity is currently generated from renewable sources, according to Ministry of Business, Innovation and Employment figures for 2014.

Genter says according to KiwiRail, China CNR Corporation - which recently sold new diesel engines to New Zealand - is now building an increasing portion of electric locomotives over time.

"Only 1 in 5 of every train they build is diesel. The vast majority of trains being built these days are electric, because that's the future."

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