Lipids contained within microalgae are attractive for the production of methane biogas. Lipids have a higher theoretical methane potential when compared to proteins and carbohydrates (Zamalloa 2012). However, due to the chemistry of lipids and the low alkalinity and buffering capacity associated with them, high lipid concentrations can be inhibitory to anaerobic digestion (Park and Li 2012; Ward et al. 2014). Inhibition by lipids is caused by the intermediate products produced during their breakdown, such as long chain fatty acids and VFAs (Park and Li 2012). When the lipid content of the microalgae is below 40 %, it has been sug­gested that the direct conversion of microalgae to methane by anaerobic digestion is more energetically favourable when compared to lipid removal from microalgae biomass (Sialve et al. 2009). However, lipid concentrations have been reported to be inhibitory to aerobic digestion at concentrations of 31 % or higher (Cirne et al. 2007). When considering many of the microalgae species used commercially for biofuel production, many have been purposely selected for a lipid concentration of 30 % or higher. Therefore, the removal of the lipid fraction for lipid-based biofuel production is highly beneficial and crucial for the anaerobic digestion process. (Cirne et al. 2007; Sialve et al. 2009). The lipid extraction methods utilised to extract microalgae lipid can also have an effect on the digestibility of the residual biomass (Ehimen et al. 2009). The solvents butanol, hexane and methanol have been shown to have no detrimental effect or inhibition to the anaerobic microbial community if the residual biomass is heated sufficiently to remove any entrained solvents (Ehimen et al. 2009). However, chloroform from the Bligh and Dyer extraction process has been shown to be detrimental to the anaerobic digester microbial community (Bligh and Dyer 1959; Thiel 1969).