Calculator
Gas bottle burn time
Choose propane or butane, the bottle size and your barbecue's total burner rating in kW. The calculator shows the hours of cooking at full power.
In short
Hours at full power = kg of gas x 12.9 kWh/kg (propane) or 12.7 kWh/kg (butane) ÷ total burner kW. A 13 kg propane bottle holds about 167.7 kWh, around 16.8 hours on a 10 kW grill. Lower settings last longer.
Work it out
Energy in the bottle
167.7 kWh
Hours at full power
16.8
Lower settings last longer.
Propane: 12.9 kWh per kg (net calorific value 46.3 MJ/kg). Rounded to 0.1 hours.
How it works
A kilogram of propane holds about 12.9 kWh of usable heat (net calorific value 46.3 MJ/kg); butane about 12.7 kWh. Multiply by the kg of gas in the bottle and divide by the total burner rating in kW to get the hours with every burner on full. Real cooks rarely run everything flat out, so lower settings last longer.
| Bottle | Energy | On 6 kW | On 10 kW | On 14 kW |
|---|---|---|---|---|
| 5 kg propane | 64.5 kWh | 10.8 h | 6.5 h | 4.6 h |
| 13 kg propane | 167.7 kWh | 28.0 h | 16.8 h | 12.0 h |
| 19 kg propane | 245.1 kWh | 40.9 h | 24.5 h | 17.5 h |
| 7 kg butane | 88.9 kWh | 14.8 h | 8.9 h | 6.3 h |
| 15 kg butane | 190.5 kWh | 31.8 h | 19.1 h | 13.6 h |
Propane
screw-on regulator
Typical sizes: 3.9, 5, 6, 13 and 19 kg
Butane
clip-on regulator
Typical sizes: 4.5, 7 and 15 kg
Patio gas (propane)
clip-on regulator
Typical sizes: 5 and 13 kg
Typical UK bottle colours and sizes; always fit the regulator made for your bottle and gas.