Enter your LPG appliances and daily usage to find out how long a 9 kg or 45 kg gas bottle will last — and what your monthly LPG cost will be.
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Add your appliances, set daily usage hours, and get an instant estimate of bottle life and cost.
Add a preset appliance:
| Appliance | Output (kW) | kg/hr |
|---|---|---|
| Hob — 2 burners at medium | 3.5 kW | 0.26 kg/hr |
| Hob — all 4 burners on | 7.0 kW | 0.52 kg/hr |
| BBQ (4-burner, all on) | 10.5 kW | 0.78 kg/hr |
| Gas space heater (small) | 3.0 kW | 0.22 kg/hr |
| Gas space heater (large) | 6.0 kW | 0.44 kg/hr |
| Continuous flow hot water | 24.0 kW | 1.76 kg/hr |
| Gas clothes dryer | 5.0 kW | 0.37 kg/hr |
| Gas fireplace | 5.5 kW | 0.41 kg/hr |
Based on 49 MJ/kg LPG energy content. Actual consumption varies by appliance efficiency and settings.
A 4-burner BBQ at full load uses ~0.7 kg/hr. A 9 kg bottle lasts about 13 hours of full-load use — or 20–30 typical BBQ sessions at partial load.
For a gas hob only, a 9 kg is convenient. If you have a gas hob plus water heater or space heater, a 45 kg cylinder on a swap arrangement costs less per kg and needs changing less often.
LPG for residential use in NZ typically costs $3.50–$5.50/kg for a 45 kg swap cylinder. Prices vary by supplier and region. A 9 kg cylinder costs more per kg when factoring in exchange fees.
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