Biomass yield on light, TAG content, TAG production rate and productivity as functions of IBS-light availability. Biomass yield on light (Y
x, ph, batch
; a), TAG content (f
; b), initial-biomass-specific TAG production rate (rTAG, IBS, batch; c) and TAG productivity (P
; d) at the end of the batch at increasing initial-biomass-specific light availabilities (I
) for the different runs in vertical (black diamonds) and horizontal (white circles) reactors.