Systems and methods presented herein generally relate to determining flaring efficiency of a flare based at least in part on radiant or thermal heat generated by the flare that is detected by one or more flare monitors. In particular, in certain embodiments, a control system may be used to determine a flaring efficiency of the combustion of the flare gas at the tip of the flare based at least in part on the radiant or thermal heat detected by the one or more flare monitors.