A software tool accompanies the guidebook to help water utilities evaluate different design and operational alternatives
based on annual energy consumption,
GHG emissions reduction, and life cycle
Energy and Water Quality
Management Systems (EWQMS)
PROJECT #4271, OPTIMIZATION of Energy
and Water Quality Management Systems for
Drinking Water Utilities (Badruzzaman et al.
2015), focuses on pumping system operation and control using Energy and Water
Quality Management Systems (EWQMS).
This type of system schedules pump-
ing operations to use the most efficient
pumps and to pump during off-peak elec-
trical tariff periods. The project, funded in
partnership with the California Energy
Commission, provides an up-to-date syn-
thesis and assessment of the current state
of knowledge on EWQMS. It summarizes
the benefits and challenges experienced
by water utilities during implementation
and operation of an EWQMS and identi-
fies best practices. The project developed
a new EWQMS module to optimize opera-
tions for greenhouse gas (GHG) emission
reduction, and summarizes the modeling
simulations and pilot operations at two
California water utilities. The project also
identifies the elements necessary for a
water utility to develop a business case
for an EWQMS implementation.
An EWQMS controls the water system
through a collection of individual application software programs, which are
user-developed or commercially available.
The programs interface with the existing
Supervisory Control and Data Acquisition
(SCADA) system to schedule the shifting
of electrical loads to lower cost tariff periods, reduce peak kilowatt (k W) demand
charges, achieve efficiency gains, and
reduce water age to improve water quality. Real-time communications with pre-existing SCADA systems allow the E WQMS
to monitor and provide recommendations
for, or direct control of, system operation
(e.g., pumping, storage tank turnover, etc.)
based on time-of-day electrical consumption and associated tariffs and forecasted
short-term water demand.
Cost savings following implementation
of an EWQMS vary annually and are utility-
dependent. For utilities with an EWQMS,
operating electricity cost savings of 5–20%
have been reported due to higher use of
cheaper tariff periods and better operat-
ing efficiencies, resulting in an approxi-
mate reduction in energy consumption
of 6–15% (with potential simultaneous
carbon emission reduction). In addition to
these economic and environmental ben-
efits, utilities with an EWQMS can better
manage their water supply portfolios and
simulate the impact of water demand pat-
terns and energy market profiles for deci-
sion making and planning.
Project #4271 confirmed that establishing pump priority strategies based on
a pump’s efficiency instead of its operational run-time provides cost-effective
and energy-efficient operation. Typically,
water utilities select pumps based on a
rotation strategy that evenly rotates all
pumps within a pumping station. The pilot
testing showed that there are cost and
energy benefits if the pumps are selected
based on efficiency, instead of a rotation
policy that evenly spreads the runtime
over all pumps.
DERCE TO, INC. 2013. Feature Case Studies.
Table 1. Passive and active influences on a pumping system
Accessed November 2013. http://www.
JENTGEN, L.A., S. Conrad, R. Riddle, E.V.
Sacken, K. Stone, W. Grayman, and S.
Ranade. 2003. Implementing a Prototype
Energy and Water Quality Management
System. Denver, Colo.: AwwaRF.
SENON, C., M. Badruzzaman, A. Contreras,
J. Adidjaja, E. Pascua, S.M. Allen, and J.G.
Jacangelo. 2015. Drinking Water Pump
Station Design and Operation for Energy
Efficiency. Denver, Colo.: Water Research
Passive Influences Active Influences
Changes in pipe diameter or wall roughness due to
corrosion, abrasion, calcification, build-up of slime, or
Changes in control schemes
Changes in static head and total dynamic head due to
varying water levels in the intake source or recipient
Use of old and inefficient motors and variable
frequency drives (VFDs)
Wearing of piping components (such as valves) and
pump components (such as casings, impellers, bearings, and wear rings)
Use of energy-wasting practices such as throttling
valves; bypass valves; high friction loss pipe sizes,
fittings, and valves
Increase in roughness of water flow passages inside
the pump due to age, corrosion, erosion, cavitation or
Changes in piping configuration
Source: Data taken from Senon et al. 2015.
Changes in the pump duty points (required head and
flow) due to changes in community planning and