Abstract: A photobioreactor for mass production of algae in a liquid pool, comprising a vessel including first and second generally parallel walls. The vessel is adapted to receive a liquid pool. A plurality of hollow tubes extends from the first wall to the second wall for receiving a light source. The hollow tubes are adapted to be immersed in the liquid pool such that the light source can illuminate the liquid pool. The hollow tubes are accessible from outside of the vessel for allowing for the servicing of the light source without having to shut down operation of the photobioreactor. Inlet ports are provided for injecting fluids into the vessel. Outlet ports are provided for extracting liquid from the vessel.