AWARDS FINALIST: Westpower – Breathing new life into old assets

Westpower says its transformer refurbishment programme has come into its own this year in terms of scale and impact.

The firm recently agreed on the purchase of 500 11 kilovolt transformers from another South Island distribution network upgrading parts of its network to 22 kV.

It is now refurbishing more than 100 transformers and about 25 air-break switches a year for return to service.

Westpower says its decision some years ago to establish a workshop to rebuild transformers was ahead of its time in terms of environmental stewardship.

Instead of scrapping ageing transformers and switches, Westpower refurbishes them in-house, restoring them to near-new condition and redeploying them across the network.

Emissions

This approach not only extends the life of critical infrastructure, but also significantly reduces embodied carbon emissions and landfill waste.

The company estimates the emissions from refurbishment are about 12 per cent of those from a newly made unit.

That means the workshop is delivering an annual emissions-saving estimated at 97.3 tonnes of CO₂ - the equivalent of planting 4600 trees or taking 21 cars off the road for a year.

And the cost savings are just as compelling; refurbishing a distribution transformer takes about 12 hours and comes at a cost of $500 to $1500, once paint, gaskets and galvanising is included.

Purchased new, transformers can cost $3000 to $60,000.

Network

Westpower has more than 3500 distribution transformers on its network, ranging from 11 kV to 33 kV.

It believes it may also be the only EDB in New Zealand refurbishing air-break switches, which are prone to corrosion in the firm's harsh West Coast environment.

By replacing insulators, knives and lightning arcing horns, re-galvanising other components and treating them with specialist epoxy paint, the team has created a cost-effective alternative to landfill disposal - at less than half the $7500 cost of new switches.

Westpower says it takes great pride in the high-quality work of its two dedicated transformer maintainers - Don and Kelly - whose expertise ensures its ongoing success.

And while it started the programme alone, the company says it is a model it is happy to share with others wanting to "do the right thing."

The annual Energy Excellence Awards will be held in Wellington on 13 August. The Low-Carbon Award is sponsored by Energy Resources Aotearoa.