Tracking Vs. Racking
What are the Trade-offs?
It stands to reason that the ideal method of installation would provide the maximum annual output while minimizing the cost, however, that is not usually attainable.
The maximum available output from any given solar collection panel is achieved with a two-axis tracking mechanism that can keep the panel facing directly at the sun, all day long, everyday year-round.
Although a comparison of costs quickly shows two-axis tracking is much more expensive to install than other methods, one can use the annual output of such a system to evaluate the relative performance of alternate mounting systems.