ghg-inventory-1990-2013

Figure 3.3.8
New Zealand’s electricity generation by source (1990–2012)
Methodological issues
1.AA.1.C Manufacture of solid fuels and other energy industries i
Methanex New Zealand
produced synthetic petrol until 1997. A Tier 1 methodology was
used to estimate emissions based onn the annual weighted average gas emission factor.
Activity data
1.AA.1.A Public electricity and heat production
All thermal electricity generators provide figures to the Ministry of Business, Innovation
and Employment for the t amount of coal, gas
and oil used for electricity generation.
Greenhouse gas emissions from geothermal
electricity generation g are reported under
1.B.2.D.
Around 6 per cent of New Zealand’s electricity
is supplied by co-generation (also known
as combined heat and power) (Ministry of Business, Innovation and Employment, 2013).
Most of the major co-generation
plants are attached to large industrial facilities that
consume most of the electricity andd heat generated.
There are six co-generation plants that fit the IPCC, 2006, definition off public electricity
and heat production that produce electricity as their primaryy purpose. The emissionss from
these plants are included under the public electricity and heat production subcategory,
while emissions from other co-generation plants are included within the manufacturing
industries and construction categoryy (section 3.3.2).
To establish a consistent approachh to on-site generation, the t national electricity system
developed a decision tree to guide the allocation of associated fuel consumption and
identify whether the plant is a main activity electricity generator g orr an autoproducer
(figure 3.3. .9).
New Zealand’ ’s Greenhouse Gas Inventory 1990–2013
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