Water need only be pumped to the top for short durations to feed a reservoir and gravity will take over from there. Electricity can be supplied from solar or wind and excess could be sold back into the grid thereby increasing the profitability of the system.
Also keep in mind that the flat system from BEHL will need electricity to pump the pig back and forth all day every day while vertical systems use the falling water to agitate their algae. BEHL could use a few solar panels of their own.