How long does each SunJel can burn?

It is nearly impossible to predict the burn time of any gel fuel. Just like a piece of firewood, the burn time for a gel fuel is completely at the mercy of the surrounding environment. Environmental factors include, but are not limited to, type of fireplace, airflow, temperature, elevation, humidity, as well as many other conditions. While it is impossible to consistently predict the burn time, the average can will burn for three hours.