Monster 90-tonne load sets Northland transport record

The supertruck and its 90-tonne load rumbles through Moerewa on Tuesday afternoon. Photo / Peter de Graaf

The biggest thing ever transported on Northland roads will form a key part of a geothermal power station being built near Kaikohe.

The 90-tonne, 20.5m-long heat exchanger made a traffic-stopping sight as it rumbled up State Highway 1 last week, carried on an 18-axle, 144-wheel trailer pulled by two trucks and pushed by one more.

The ''supertruck'' slowed to walking pace as it travelled through Kawakawa and Moerewa and strained up Turntable Hill, and was accompanied by a fleet of support vehicles throughout the 120km trip.

The heat exchanger arrived by ship at Northport and was transported by Palmerston North firm PTS Logistics to Top Energy's new geothermal power station at Ngāwhā, just east of Kaikohe.

The supertruck and its 90-tonne cargo slowed to walking pace as it climbed Turntable Hill. Photo / Peter de Graaf

Top Energy chief executive Russell Shaw said the Israel-built heat exchanger, or pre-heater, was used to extract energy from geothermal fluid drawn from deep underground.

Heat from the fluid turned pentane into a high-pressure gas which spun a series of turbines. The turbines then turned a generator, making electricity.

Shaw said the heat exchanger was part of the second shipment of parts from Israel. The third and final shipment, which would include the generator, was expected in late January or early February. He apologised for any inconvenience to road users.

The 90-tonne, 20.5m-long power station heat exchanger is believed to be the biggest thing ever transported on Northland roads. Photo / Peter de Graaf

The 90-tonne heat exchanger is believed to be the biggest object ever transported on Northland roads, eclipsing an 85-tonne transformer trucked from Marsden Pt to Kaitaia in 2015, also for Top Energy.

That trip took two days and involved hauling the transformer over the Mangamuka Ranges because the truck was too wide for the then one-lane Taipa Bridge.

The new power station is due to start producing electricity in August next year.