Retrotec USACE - Manual (Page 231)

Appendix D D101
D.6 Electrical Systems
D.6.1 Motors
D.6.1.1 Running When Not Required (Waste)
Figure D158. Heating water distribution pump
runs continuously in winter even though no
hot water is needed.
Electric motors power a wide range of equipment in industrial facilities, many
of which are taken for granted and assumed to be functioning whenever needed
(Figure D158). When these systems are not being used, energy waste occurs.
The greatest type of energy waste is running things that are not required. In
an industrial plant, common examples are compressed air systems, conveyors,
ventilation equipment, and hydraulic equipment. All of these systems use elec-
tric motors to power them, and they support industrial processes. Their opera-
tion can be made more effi cient with the use of controls that can sense when
process equipment is not operating the support equipment—the hydraulic
pumps can also be shut down or go into a standby mode. A tour of the indus-
trial facility, especially on the weekend or during a shift when the production
equipment is off, will help identify these systems and other electrical motors
that are continuing to operate for no reason.
D.6.1.2 Motors More Than 3 hp That Are Less Than 85% Effi cient
(Ineffi ciency)
Figure D159. Standard effi cient motor
powering a fan.
A 11.4 W (3 hp) standard motor has an effi ciency of 82% (Figure D159). It can
be replaced with a premium effi ciency motor that has an effi ciency of 89.7%.