4. Technology parameters

4.1. Equipment lifetimes

Equipment lifetimes are taken as estimated useful life (years) from the Inland Revenues General depreciation rates October 2024 document[1]. Table 7 includes the IRD proxies considered to estimate lifetime of each technology. Where not available, data are taken from industry sources/knowledge[2].

Table 25 Equipment lifetime by technology

Technologies	Lifetime (Years)	IRD Proxies
Electronics and Other Appliances	4	RESD - Appliances (small)
Lights (Incandescent)	1	N/A
Lights (Fluorescent)	3	N/A
Lights (LED)	10	N/A
Boiler	25	BOIL - Boilers
Burner (Direct Heat)	12.5	BOIL – Space heaters
Direct Heat	12.5	BOIL – Space heaters
Heat Pump	10	RESD - Air conditioners and heat pumps/ Water heaters (heat pump type)
Resistance Heater	10	RESD - Air conditioners and heat pumps/ Water heaters (heat pump type)
Hot Water Cylinder	15.5	RESD - Water heaters (other)
Internal Combustion Engine (Land Transport)	20	TRAN - Forklift trucks (8 tonnes and over
Stationary Engine - Electricity	10	BDFO - Motors
Stationary Engine - Petrol	20	POWR - Generators (oil fired)
Refrigerator	8	MEDI - Refrigerators
Cooking Element	12.5	HOTS - Cookers
Oven	20	BAKE - Ovens (built-in)

4.2. Availability factors (AF)

Availability factors were estimated separately for each commercial subsector in TIMES-NZ 2.0. The calculation was based on the underlying load curves prior to normalisation (i.e., before scaling so that all time-slice fractions sum to 1.0). This ensures that the availability factors reflect the absolute intensity and timing of energy use rather than just the relative distribution. For most end-uses, it was assumed that technologies operate concurrently during business operating hours and thus follow the sectoral load curve. Exceptions were introduced for end-uses with different utilisation patterns: space heating and cooling were scaled down to reflect their seasonal operation, while mobile motive power (e.g., equipment used intermittently) was assigned a lower availability factor than the primary continuously operated technologies.

Table 26 lists the assumed number of average active hours per day. These are converted into availability factors for the model (eg 2.4 active hours implies a 10% availability factor).

Table 26 Commercial technology availability factors

Technology	Education	Healthcare	Office Blocks	WSR	Other
Cooking	5.3	11	10.8	11.5	13.2
Process Heat	5.3	11	10.8	11.5	13.2
Electronics	5.3	11	10.8	11.5	13.2
Lighting	5.3	11	10.8	11.5	13.2
Space Heating	2.4	2.4	2.4	2.4	2.4
Water Heating	5.3	11	10.8	11.5	13.2
Internal Combustion Engine (Land Transport)	1.2	1.2	2.4	11.5	2.4
Stationary Engine	5.3	11	10.8	11.5	13.2
Refrigeration	5.3	11	10.8	11.5	13.2
Space Cooling	2.6	5.5	5.3	5.8	6.5

4.3. Energy efficiency

A full list of energy efficiency assumptions can be found in Table 27. Energy efficiencies of most technologies came from the TIMES-NZ 2.0 model. Efficiencies for internal combustion engine (land transport)[3], stationary engines[4], and cooking ovens[5] were updated using literature reviews.

Table 27 Energy efficiency by technology

Technology	Fuel	Energy Efficiency %
Boiler Systems	Coal	75%
Boiler Systems	Diesel	85%
Boiler Systems	LPG	85%
Boiler Systems	Natural Gas	85%
Burner (Direct Heat)	Coal	77%
Burner (Direct Heat)	LPG	80%
Burner (Direct Heat)	Natural Gas	80%
Heat Pump Air Source	Electricity	350%
Heat Pump (Water Heating)	Electricity	250%
Resistance Heater	Electricity	99%
Direct Heat	Geothermal	100%
Hot Water Cylinder	Electricity	90%
Hot Water Cylinder	Natural Gas	60%
Incandescent Lamp	Electricity	2%
Fluorescent Lamp	Electricity	14%
LED Lamp	Electricity	25%
Internal Combustion Engine (Land Transport)	Diesel	20%
Internal Combustion Engine (Land Transport)	LPG	12%
Internal Combustion Engine (Land Transport)	Petrol	20%
Stationary Engine	Electricity	90%
Stationary Engine	Petrol	14%
Refrigerator	Electricity	180%
Electronics	Electricity	90%
Cooking Elements	Electricity	74%
Cooking Ovens	Electricity	76%
Cooking Ovens	LPG	49%
Cooking Ovens	Natural Gas	49%

4.4. Capital costs

A full list of capital cost assumptions can be found in Table 28 below. These capital costs represent the upfront expenditure required to install each technology in a typical New Zealand commercial building context. Costs are expressed in NZD per kW of installed capacity and include both the equipment and standard installation. For example, capital cost of a gas boiler reflects the unit cost plus typical installation labour and materials. Operating costs (fuel, maintenance, servicing) are not included.

The sources for these estimates include EECA research and case studies, government datasets, and New Zealand supplier price lists. For example, EECA’s industrial decarbonisation reports and hot water heat pump guidance[6]^,[7] provide comparative project costs, the New Zealand Geothermal Association provides costs of the geothermal direct heat for delivered energy[8], and retail suppliers[9] provide market-based prices for appliances and smaller equipment.

Cost values are adjusted to 2023 New Zealand dollars using the most appropriate price index (CPI or CGPI).

Table 28 Capital costs by technology

Technology	Fuel	Capital cost (NZD/kW)
Boiler Systems	Coal	1,000
Boiler Systems	Diesel	380
Boiler Systems	LPG	250
Boiler Systems	Natural Gas	250
Boiler Systems	Wood	2,190
Burner (Direct Heat)	Coal	600
Burner (Direct Heat)	LPG	300
Burner (Direct Heat)	Natural Gas	300
Burner (Direct Heat)	Biogas	300
Heat Pump Air Source[10]	Electricity	1,200
Heat Pump (Water Heating)	Electricity	1,200
Resistance Heater	Electricity	50
Direct Heat	Geothermal	150
Hot Water Cylinder	Electricity	500
Hot Water Cylinder	Natural Gas	100
Incandescent Lamp	Electricity	15
Fluorescent Lamp	Electricity	112
LED Lamp	Electricity	500
Internal Combustion Engine (Land Transport)	Diesel	200
Internal Combustion Engine (Land Transport)	LPG	200
Internal Combustion Engine (Land Transport)	Natural Gas	200
Internal Combustion Engine (Land Transport)	Petrol	222
Electric Motor	Electricity	185
Stationary Engine	Petrol	200
Refrigerator	Electricity	5,000
Electronics	Electricity	5,000
Cooking Elements	Electricity	200
Cooking Ovens	Electricity	250
Cooking Ovens	LPG	200
Cooking Ovens	Natural Gas	200
Pumps	Electricity	185

Some distinction between the costs of technologies were added, to represent the fact that some subsectors will pay significantly more than others for the same technology, due to their requirements or scale. For example, previous EECA projects have found that a school will pay 5-10x more per kW for their heating or lighting CAPEX than an equivalent office building. This is primarily due to the scaling of these organisations, schools are likely to span many small buildings over a relatively large area, each only needing a relatively small amount of heating. Office blocks can take advantage of their higher density, giving a more centralised area to heat, and a larger, more cost-effective heating option can be purchased.

4.5. Operating and maintenance costs

Operating and maintenance costs assumptions for some technologies can be found in Table 29. These have been extracted from the TIMES-NZ 2.0 model. Technologies not listed here are assumed to have 0 additional operating or maintenance costs.

Table 29 Operating and maintenance costs

Technology	Fuel	O&M cost (NZD/kW/year)
Boiler Systems	Coal	15
Boiler Systems	Diesel	3
Boiler Systems	LPG	2
Boiler Systems	Natural Gas	2
Internal Combustion Engine (Land Transport)	Diesel	7
Internal Combustion Engine (Land Transport)	LPG	7
Internal Combustion Engine (Land Transport)	Petrol	7
Internal Combustion Engine (Land Transport)	Natural Gas	7
Stationary Engine	Petrol	5
Refrigerator	Electricity	5

4.6. Fuel market share constraints

Market shares for technologies and fuels for each demand of each sub-sector were added in the TIMES-NZ 2.0 model to avoid near complete uptake of technologies at an unrealistic rate. As TIMES-NZ is a least-cost model, when not limited it was immediately replacing the bulk of its technologies with whichever was cheapest, resulting in a near complete uptake of electrification from 2020 onwards.

The base year of 2023 was estimated using the EEUD, with 2030 and 2050 projections being made based upon assumptions of the TIMES-NZ team. For example, the EEUD has only 1% of school heating demand being met by heat pumps. While we see this as a definite growth area, we don’t expect 100% uptake by 2030, so we have limited this to 50%. By 2050, we have raised this to 70%, allowing the remainder to be supplied by resistance heaters and gas or biomass boilers.

Please note these are maximum bounds, i.e. they are the maximum that one fuel/technology combination can provide output, so numbers in 2030 and 2050 may sum to over 100%. This gives the model room to choose preferred technologies, but limited at a realistic rate, without prescribing the total of each fuel/technology.

4.7. Emission factors

Emissions factors for each thermal fuel are sourced from the Ministry for the Environment’s Measuring Emissions Guide 2025[11]. These are all converted to kt CO2e/PJ equivalents using gross calorific values from MfE’s data for use in modelling. The electricity supply portion of the model will handle the electricity emission factor for commercial electricity. The following figures are used in the model:

Table 30 Thermal fuel emission factors

Fuel	Unit	CV MJ/Unit	kg CO2e/unit	kt CO2e/PJ
Coal	kg	25.62	2.11	82.37
Natural Gas	GJ		54.1	54.1
Petrol	Litre	35.18	2.41	68.79
Diesel	Litre	38.49	2.68	69.63
LPG	kg	50	2.97	59.32

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[1]

Inland Revenue | General depreciation rates August 2024

[2]

An incandescent bulb typically last around 2,000 hours, a fluorescent lamp around 10,000 hours, and an LED lamp around 30,000 hours Choosing a lamp and how you can save money on energy efficiency, How to buy LED bulbs - Consumer NZ

[3]

Estimation of tank-to-wheel efficiency functions based on type approval data, Comparison of the Overall Energy Efficiency for Internal Combustion Engine Vehicles and Electric Vehicles

[4]

GNS | Technology scan of electric motors applications

[5]

Energy Star | Commercial Oven Key Product Criteria

[6]

EECA | Hot water heat pumps in commercial buildings

[7]

EECA | Heatpumps for process heat

[8]

NZGA | Action Plan 2024-2025

[9]

Various prices pulled from retail sites, including: Kiwi heat pumps, Hot water cylinders, Mitre 10, Bunnings, and OMC Power Equipment

[10]

Commercial heatpump installation costs include estimated costs of replacing existing commercial heating solutions. Costs for new builds may vary.

[11]

MfE | Measuring Emissions Guide 2025