Handbook of Civil Engineering Calculations

FIGURE 19. Closed-cycle system gassifies refrigerant in boiler to drive

Rankine-cycle turbine for pumping water. (Product Engineering, Bat-

telle Memorial Institute, and Northwestern Mutual Life Insurance Co.)

In this solar-powered pumping system, water is drawn from a sump basin and pumped
to an irrigation canal where it is channeled to the fields. The 50-hp (37.3-kW) motor was
chosen because it is large enough to provide a meaningful demonstration of commercial
size and it can be scaled up to 200 to 250 hp (149.2 to 186.5 kW) quickly and easily.
Sensors associated with the solar collector aim it at the sun in the morning, and, as the
sun moves across the sky, track it throughout the day. These same sensing devices also
rotate the collectors to a storage position at night and during storms. This is done to lessen
the chance of damage to the reflective surfaces of the collectors. A backup control system
is available for emergencies.

Irrigation

canal

Pump

Feed pump

Condenser

Cooling

system

Regenerator Turbine

Pump

Preheater

Refrigerant

system

Boiler

Hot water system

Solar collector