To date, the most effective strategy to increase photosynthetic light utilization efficiency is to reduce the size of the light-harvesting antenna per RC complex [5], [8] and [10]. By reducing the effective optical cross section of the antennae complexes the probability of saturating electron transfer at full sunlight intensities is reduced. Significantly, a reduction in antennae size/RC is also predicted to reduce cell shading and increase the penetration of photosynthetically active radiation to greater depths in the culture water column (Fig. 1A). In Chlamydomonas reinhardtii, it has been demonstrated that mutants with reduced antenna size can be generated by eliminating chlorophyll (Chl) b synthesis as well as by reducing expression of LHC genes [10] and [11]. Previous studies have shown that microalgae lacking the peripheral LHCII have increased photosynthetic rates; however, few studies have demonstrated an increase in growth rate with reduced peripheral antennae size under fully autotrophic growth conditions [8], [11], [12], [13], [14] and [15]. To date, nearly all growth studies with algae having altered antennae sizes have been done under mixotrophic (plus acetate) growth conditions.