Page 164 - Solar Power in Building Design The Engineer's Complete Design Resource

134 SOLAR POWER GENERATION PROJECT IMPLEMENTATION

Figure 5.15 Grid-connected solar pumping system diagram.
Photo courtesy of WorldWater & Power Corporation.

cooling, and water utilities, making it the first company in the world to deliver main-
stream solar electric pumping capacity.

THE AQUAMAX SYSTEM KEY FEATURES

In general, grid power normally provides the power to the pumps. With the AquaMax
system, in the event of power loss, the system automatically and instantaneously
switches power fully to the solar array. In keeping with the islanding provisions of the
interconnection rules, when the power to the grid is off, the pump or motor keeps
operating from solar power alone without interruption. This solar pumping system is
the only one of its kind; other grid-tied solar power systems shut down when grid
power is interrupted.

Power-blending technology The AquaMax seamlessly blends dc power from
the solar array and ac power from the grid to provide a variable-frequency ac signal
to the pump or motor. This does two important things. It eliminates large power
surges to the motor, and so reduces peak demand charges in the electric bill. It also
increases the efficiency of the motor, so it uses less energy to operate. This power-
blending technology also means that motors benefit from a “soft start” capability,
which reduces wear and tear on the motor and extends its life.