A B S T R A C T Microalgae can provide solutions to the twin challenges of energy security and environmental pollution. They can capture carbon dioxide in the flue gas thereby reducing greenhouse gas and also producing algal biomass, which can be converted into biofuel. The present study evaluated the effects on growth and lipid content of Nannochloropsis sp., under reduced nitrogen content and enrichment with sodium carbonate/bicarbonate derived from flue gas. Studies have been conducted to identify and develop efficient lipid induction techniques in microalgae, such as nutrients stress (e.g., nitrogen and/or phosphorus starvation), osmotic stress, radiation, pH, temperature, heavy metals and other chemicals. Our results showed that the total lipid productivity of Nannochloropsis sp. cultures aerated with five different CO 2 levels (1, 10, 15, 20 and 25% CO 2 ) had the highest lipid level of 18.93 mg LG 1 dayG 1 for the 15% CO 2 . The growth using soluble carbonates was slightly better than when using only CO 2 gas as carbon source. The 20% flue gas solution gave maximum yield of dry biomass of 0.55 g, while the maximum yield of dry biomass for 15% dissolved CO 2 gas was around 0.44 g. In terms of nitrogen level; the concentration of nitrogen at 0.882 mM gave the best growth and biomass amount. Those with lower nitrogen had their growth and biomass reduced by almost 5 times. Lipid productivity increased when exposing the culture to nitrogen starvation condition. The 100% N cultures (0.882 mM) yielded the lowest lipid productivity, while the 25% N cultures (0.353 mM) showed the highest productivity of lipid. The cells that grew in the lowest nitrogen content showed slightly more than twice the productivity of oil production compared with the one with 100% N cultures. This work has described the favorable conditions for lipid production by Nannochloropsis sp. in respect to CO 2 gas, soluble carbonates and different nitrogen concentrations.