Provided herein are controlled methods for producing biofuel and lipids from algae. In certain embodiments, the controlled methods comprise: (i) providing upwelled water in a body of water； (ii) culturing algae in the upwelled water； (iii) feeding the algae to planktivorious organisms； (iv) extracting lipids from the planktivorious organisms； and (v) polishing the lipids to make biofuel or other useful products. In certain embodiments, the upwelled water is provided in the body of water by using an open-cycle OTEC system. Also provided herein are controlled systems for producing biofuel and lipids from algae.
