The third element of the strategy was to focus initially on what appeared to be the most promising drop-in fuel, biodiesel,as demonstrating economically sustainable production of this bio-fuel would encourage a smooth transition from lower-productivity agricultural biomass (e.g. corn for ethanol) to higher-productivity algal biomass as a feedstock, while exploiting existing distribution infrastructure. Because lipids can serve as biodiesel precursors,algal strains that accumulate easily extracted lipids in laboratory culture were chosen for initial development. Initial analyses, using assumptions then considered conservative suggested that microalgal biodiesel was potentially economically feasible if production improvements could be implemented (Chisti, 2007; Wijffels andBarbosa, 2010; Chisti, 2013; Dassey et al., 2014; Rogers et al., 2014).