Coal, gas data shows New Zealand ‘lurching from crisis to crisis’

Genesis Energy's Huntly Power Station supports NZ's electricity system when lake levels are low. Photo / NZME

New Zealand relied heavily on coal and gas-driven power generation from April to June this year, a government report says.

Data from the Ministry of Business Innovation & Employment (MBIE) showed low hydro lake levels meant electricity generated from renewable sources dropped to 81.3% of total generation, an 8.6% decline compared to the same period last year.

For the first time since June 2021, and despite a 50% increase in wind capacity, coal generated more electricity than wind.

“Coal-based electricity generation increased to 883 gigawatt hours (GWh) for the quarter, compared to 144 GWh of generation in the same quarter last year,” MBIE domains manager Amapola Generosa said.

“Electricity generation from natural gas increased 43.9% on the same quarter last year, contributing 10.7% of overall electricity generation for the quarter, but due to limitations in natural gas supply, it wasn’t able to fully cover the drop in hydro generation for the quarter.

“Contributing 7.9% of total generation for the quarter, coal-fired generation was required to support gas-fired generation in making up for the reduction in generation from hydro,” Generosa said.

On the supply side, net production of gas was down 19%.

Decreasing gas supply resulted in a drop in gas use, with large users responding by continuing to operate at lower levels.

Electricity generation from geothermal was the highest on record for a quarterly basis with 2,143 GWh generated, contributing 19.1% of total generation for the quarter.

This record was achieved by the new Tauhara geothermal station near Taupō coming online and supply being at normal levels compared to the same time last year when geothermal generation was lower than usual due to outages at a number of plants.

“Increased electricity generation from non-renewable sources saw emissions from electricity generation reach the highest level on a quarterly basis since June 2021 with 1431 kilotonnes of CO2 emissions, representing a 169% increase from the previous June quarter.

Energy Resources Aotearoa chief executive John Carnegie said the data showed that New Zealand’s energy system was “lurching from crisis to crisis”.

“Decreasing gas supply has meant we’ve seen large users operating at lower levels, and in some cases unfortunately, forced to close,” he said.

“While we acknowledge the heavy lifting Genesis is doing to protect our nation’s energy security with its coal-fired Huntly plant, New Zealand homes are now reliant to an uncomfortable degree on imported coal to stay warm during the winter.”

Energy Resources’ members include some of the big international oil and gas companies, and local players such as Todd Energy.

Jamie Gray is an Auckland-based journalist, covering the financial markets and the primary sector. He joined the Herald in 2011.