If you have chosen "Energy-Cumulative" as the data to display, then you will see a curve showing the total amount of energy that has been generated by the chosen PV array at different times of the day, up to the time shown in the display's title block.  The unit of measurement is kWh. A technical definition of "Energy" is given in a section below.  At the start of each day, the cumulative energy value is set to zero and the energy generated is accumulated and displayed as the day progresses. The data is updated approximately every minute.

Flat panel PV arrays typically create a flattened "S" shape cumulative energy curve. Energy generation early and late in the day is limited by the low sun angle and this is reflected in the gently sloping cumulative energy curve at those times of the day. In the middle of the day, when the sun is more at right angles to the panels, energy is generated at a fast rate and the cumulative energy curve is steep (assuming no clouds). The Concentrating Array, however, points at the sun all day. When the sky is clear, this means the array generates energy all day at a fairly constant rate; this means the cumulative energy "curve" is in fact very straight for most of the day.