Balance tables
New Zealand’s energy production comes from both renewable and non-renewable sources. The energy balance tables show how energy supply and demand by sector varies by energy type.
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Domestic energy supply is derived from either indigenous production or imported from overseas sources. In turn, energy types can be transformed into different forms of energy at the cost of losses and inefficiencies, which vary by the transformation process used. Supply, demand, losses, and inefficiencies are reflected in balanced energy supply and demand tables.
Both the energy supply and demand sections of the energy balance tables are calculated from surveys that span different sources. An imbalance exists between demand calculated from reported supply data, and demand observed from reported consumption data.
Energy supply
Total primary energy supply (TPES) is the amount of energy available for use in New Zealand. Much of it is converted into other forms of energy before it is used.
By convention, fuel used for international transport is excluded from TPES. International transport includes international sea and air transport but excludes coastal shipping, national air transport, and all land transport.
Indigenous natural gas production does not include natural gas that is flared, reinjected, or extracted as LPG. The primary energy figures presented are actual data, except for some that go into electricity generation as detailed under energy transformation.
Energy transformation
Energy transformation includes:
- generation of electricity, including cogeneration
- oil production, including refinery operations and the manufacture of synthetic fuel from natural gas (Methanex stopped the production of methanol to petrol in April 1999)
- other transformation, primarily steel production.
In the Energy Transformation section of the balance tables, ‘energy in’ is shown as negative values and ’energy out’ as positive values in the appropriate columns. Transformation of energy from one form to another always results in conversion losses, particularly in thermal electricity generation, as much energy is lost as heat.
Transformation losses in electricity generation are calculated using the net electricity generated, with the actual input being used where available. The conversion factors shown in Table 1 are used otherwise. Input to electricity generation from biogas, hydro, wind, and waste heat are fully estimated. Quarterly figures for electricity generation are made up of actual data from major generators and the Electricity Authority. Estimates are made where actual data are unavailable at the time of publishing.
Default electrical transformation factors
| Fuel | Default efficiency |
|---|---|
| Biogas | 30% |
| Coal | 30% |
| Gas (combined cycle) | 55% |
| Gas (single cycle) | 30% |
| Geothermal | 15% |
| Hydro | 100% |
| Oil | 30% |
| Waste heat | 15% |
| Wind | 100% |
| Wood | 25% |
Liquid biofuel production (bioethanol and biodiesel) appears as renewable energy supply in the energy balance tables. As bioethanol and biodiesel are generally blended with motor petrol and diesel before consumption, liquid biofuel also appears in Energy Transformation under Fuel Production.
Consumer energy demand
Consumer energy is the amount of energy consumed by final users. It excludes energy used or lost in the process of transforming energy into other forms and in bringing the energy to the final consumers. For example, natural gas is a primary energy source, some of which is transformed into electricity, of which some is lost in transmission to consumers.
Consumer energy statistics can be either calculated from supply-side data or observed from usage data.
- Consumer energy (calculated) forms the top half of the energy balance tables. It is calculated as TPES less energy transformation less non-energy use.
- Consumer energy (observed) forms the bottom half of the energy balance tables. It represents reported demand in the agricultural, industrial, commercial, transport, and residential sectors. With the exception of domestic use of energy for on-road, rail, sea, and air transport in the transport sector, these sectors follow the Australia New Zealand Standard Industrial Classification 2006 definitions. Estimates of on-site cogeneration demand are included in electricity end use.
Where the energy end-use is not available or confidential, the ‘unallocated’ category is used.
Statistical differences
Statistical differences show the difference between ‘consumer energy (calculated)’ and ‘consumer energy (observed)’. This difference is shown at the bottom of the energy balance tables.
Energy balance tables
Download the energy balance tables for the 1990 to 2023 period.
Energy balance tables – 1990 to 2023 [XLSX, 2.2 MB]
All figures have been converted into petajoules using gross calorific values.