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Non-hydro Generation

Background | Current Non-hydro Situation | Generation Mix | Thermal Plant Availability | Related Information

Background

Coal-, gas- and oil-fired (collectively 'thermal') generation typically make up about 25-35% of New Zealand's total annual electricity supply. Geothermal, cogeneration and wind collectively contribute about 15-20%. Thermal output varies from year to year and season to season depending on hydro storage and inflows. In extended dry periods more thermal generation is needed to conserve hydro storage.

No generator is 100% reliable. When major thermal generators are unavailable for an extended period, there can be an adverse effect on security of supply.

Current Non-hydro Situation

Thermal generation availability is forecast to be normal over the next few months.

Generation Mix

The table below gives the breakdown of generation sources for the last three months.

Generation Source	Energy Last 13 Weeks	Energy Last 4 weeks	Energy Last Week	Change this week to last week	Pie Chart
Co generation	252 GWh	85 GWh	19 GWh	-1 GWh
Geothermal	1446 GWh	444 GWh	108 GWh	-3 GWh
Hydro	4394 GWh	1303 GWh	340 GWh	16 GWh
Thermal	3031 GWh	1082 GWh	280 GWh	5 GWh
Wind	466 GWh	153 GWh	38 GWh	2 GWh

Thermal Plant Availability

The above graph shows planned thermal capability (columns) over the next six months, compared to maximum capability (line). Planned capacity is maximum capacity adjusted for planned outages (times when thermal stations are expected to be out of service for maintenance).

In fact, actual thermal output in any given month will be some fraction of the bars, reflecting market conditions at the time, available fuel, unplanned outages, any transmission constraints, and system operation requirements.

Thermal generation availability is forecast to be normal over the next few months.
Geothermal generation is also not included.