Civil Engineering Reference
In-Depth Information
+
Phase Angle,
0
Current,
I
Voltage, E
0
90
°
180
°
270
°
360
°
-
1 Cycle
Fig. 30-3.
Instantaneous power in an AC circuit with current lagging voltage
criteria for the processes listed in Table 30-2 are listed in Table 30-3. As shown in
Table 30-2, finished water pumping is by far the largest energy-consuming process.
Data from Table 30-2 are graphically presented in Figure 30-4, which depicts the
relative distribution of energy at a 10-mgd (38-ML / d) facility.
ENERGY EFFICIENCY CONSIDERATIONS FOR WATER SYSTEMS:
AN OVERVIEW
Energy efficiency must focus on both existing facilities and new construction. The
following issues issues related to energy efficiency are discussed in detail in this
chapter:
Energy optimization studies
•
Electric motors
•
Variable-speed drives
•
Electric utility billing schedules
•
Energy management systems
•
Supervisory control and data acquisition (SCADA) systems
•
Optimum conveyance systems
•
Pumping considerations
•
Lighting
•
Water conservation
•
