Home heating

Annual heat demand

0 kWh/yr

Peak envelope loss

0.00 kW

Heating degree days

0 K·day (base 18)

Floor area

0.0 m²

Appliance sizing guide: 0.00 kW output (peak loss +15% margin). Enter surface dimensions to size the appliance. WHO recommends a minimum 18 °C indoors, 16 °C in bedrooms overnight.

• Heat pump (high-wall split)366 MJ/yr
  Appliance EE 366 · fuel EE 0 · fuel content 0 MJ
• Wood stove (enclosed burner + flue)153 MJ/yr
  Appliance EE 153 · fuel EE 0 · fuel content 0 MJ
• Electric oil-filled column heater223 MJ/yr
  Appliance EE 223 · fuel EE 0 · fuel content 0 MJ

• Heat pump (high-wall split)COP/efficiency 5.56
  Fuel used0 kWhAnnual cost$0Annual carbon0 kg CO₂eLifetime energy (10 yr)3,655 MJ
• Wood stove (enclosed burner + flue)69% efficient
  Fuel used0.00 t firewoodAnnual cost$0Annual carbon0 kg CO₂eLifetime energy (25 yr)3,812 MJ
• Electric oil-filled column heaterCOP/efficiency 1.00
  Fuel used0 kWhAnnual cost$0Annual carbon0 kg CO₂eLifetime energy (3 yr)670 MJ

Mitsubishi SRK20ZJX-S · assumed life 10 years · 3,655 MJ total, annualised to 366 MJ/yr.

• Cast iron · 37.9 kg × 70 MJ/kg2653 MJ
• Galvanised steel · 12 kg × 34.8 MJ/kg418 MJ
• Copper tubing · 6.4 kg × 70.6 MJ/kg452 MJ
• Refrigerant fluid (R-600a) · 2.7 kg × 49.1 MJ/kg133 MJ

EECA ENERGY STAR top performer at COP 5.56 (7 °C, H1). 10-year life assumed because the rated COP is only guaranteed for 10 years. Lowest overall life-cycle energy of the three systems studied.

• Hydro · 55.7%55 kJ/kWh
• Geothermal · 18.0%95 kJ/kWh
• Gas · 9.4%11537 kJ/kWh
• Wind · 6.5%70 kJ/kWh
• Coal · 5.7%3714 kJ/kWh
• Co-generation, biogas and waste · 4.1%2600 kJ/kWh
• Solar PV · 0.6%430 kJ/kWh

Renewable share

84.9%

Grid carbon (default)

0.074 kg CO₂e/kWh

Embodied energy of electricity

1458 kJ/kWh

EE coefficient

0.40

New Zealand generation is dominated by hydro and geothermal, so delivered electricity carries little upstream energy and very low carbon. Heat pumps are therefore the lowest life-cycle energy and carbon option in almost every New Zealand climate; dry-year thermal peaking (gas and coal at Huntly) is the main source of variation between years.

Mix: MBIE Energy in New Zealand / Electricity statistics (2023 calendar year) — ~87% renewable generation. Carbon: Ministry for the Environment, Measuring emissions: a guide for organisations (2023) — electricity consumption factor. Firewood: 16.2 MJ/kg delivered energy content with 5% embodied energy. The source paper's reference case supplies 3,604 kWh of heat per year to a single room (New Zealand 2009 mix, 3008 kJ/kWh, coefficient 0.84).

• Bakshi, N., Vale, R. & Vale, B. (2013) “Which heater should I choose? A comparative study of appliances and fuel sources”, Cutting Edge: 47th International Conference of the Architectural Science Association (ANZAScA), pp. 335–344
• Alcorn, A. (2003) Embodied Energy and CO₂ Coefficients for New Zealand Building Materials, Centre for Building Performance Research, Victoria University of Wellington
• EECA (2013) ENERGY STAR appliance ratings and Energy End Use Database — space heating is ~29% of typical NZ household energy
• Ministry for the Environment (2013) recommended low-emission wood burners; NES for Air Quality burner rules
• Rule, B. (2009) New Zealand electricity generation mix — 55.2% hydro, 21.8% gas, 12.2% coal, 7.6% geothermal, 3.2% wind
• Isaacs, N. et al. (2006) Energy Use in New Zealand Households (HEEP Year 10), BRANZ — space heating ≈ one third of household energy
• ISO 14040:1997 Environmental Management — Life Cycle Assessment: Principles and Framework
• World Health Organization recommended minimum indoor temperature 18 °C (16 °C in bedrooms overnight)

⚠️ Life-cycle figures are drawn from a 2013 New Zealand study of a single-room heating regime and are scaled to this building's steady-state heat demand. They exclude installation, maintenance, transport of fuel, comfort and air-quality effects, and assume a fixed electricity generation mix. Use for comparison and feasibility only; confirm appliance selection with the current EECA/manufacturer data and your local council's air-quality rules.