A lighting control system for controlling illumination in a space, the lighting control system comprising a controller arranged to control light output of a luminaire (160-n) based at least in part on a sensor signal (150-k) from a motion sensor (140-k) arranged to observe movement in said space, the controller comprising: an occupancy determiner arranged to derive a time series of occupancy indications based on the sensor signal (150-k), wherein each occupancy indication indicates one of occupancy or non-occupancy in said space at the respective time instant, an occupancy predictor arranged to derive a predicted occupancy state of said space for a lookahead period based on occupancy indications within a lookback period; and a lighting controller arranged to provide predictive control of the light output from the luminaire (160-n) based on the predicted occupancy state, characterized in that the lighting controller is further arranged to: one of switch or keep the light on in response to the predicted occupancy state indicating occupancy, and initiate reduction of the light output to take place within a predefined delay period in response to the predicted occupancy state indicating non-occupancy, wherein the lighting controller is further arranged to carry out the following after said lookahead period: compute energy consumption during said lookahead period; and shorten the duration of said predefined delay period for the next lookahead period in response to the energy consumption during said lookahead period exceeding a predefined energy consumption threshold. an occupancy determiner arranged to derive a time series of occupancy indications based on the sensor signal (150-k), wherein each occupancy indication indicates one of occupancy or non-occupancy in said space at the respective time instant, an occupancy predictor arranged to derive a predicted occupancy state of said space for a lookahead period based on occupancy indications within a lookback period; and a lighting controller arranged to provide predictive control of the light output from the luminaire (160-n) based on the predicted occupancy state, characterized in that the lighting controller is further arranged to: one of switch or keep the light on in response to the predicted occupancy state indicating occupancy, and initiate reduction of the light output to take place within a predefined delay period in response to the predicted occupancy state indicating non-occupancy, one of switch or keep the light on in response to the predicted occupancy state indicating occupancy, and initiate reduction of the light output to take place within a predefined delay period in response to the predicted occupancy state indicating non-occupancy, wherein the lighting controller is further arranged to carry out the following after said lookahead period: compute energy consumption during said lookahead period; and shorten the duration of said predefined delay period for the next lookahead period in response to the energy consumption during said lookahead period exceeding a predefined energy consumption threshold. compute energy consumption during said lookahead period; and shorten the duration of said predefined delay period for the next lookahead period in response to the energy consumption during said lookahead period exceeding a predefined energy consumption threshold.