We never burn both burners at full power. Since we don't carry this cooker in a backpack but in the car, we don't use cartridges: However, with a Campinggaz R904 1.8 kg butane gas bottle (attention: adapter needed) it lasts for two to three weeks with daily use. So it could be that the 100g cartridge is already enough for 1h (assuming that we heat for approx. 1h per day for 14-21 days). To know exactly, you would have to do the math.