OUR PASSION FOR WATER
IS REFLECTED IN ALL WE DO.
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source (Santa Clara Valley Water District) as
water flowed into an onsite 21-million-gal-lon
reservoir. The facility also had five boost-er
pumps and a PG&E three-phase, 480
VAC transformer continuously consuming
energy. Once the site was chosen, SJWC
worked with SOAR Technologies, Inc., a de-signer
and integrator of conduit hydropower
equipment and control systems, to evaluate
and select the necessary equipment.
The Cox Avenue Station pressure-reduc-tion
hydro turbines operate continuously
with variable flows ranging from 4MGD-
14MGD and variable differential pressures
(45 to 65 PSIG) depending on the sea-son.
SOAR Technologies determined that
installing two 50 percent capacity units
with a total generating capacity of 110kW
offered the optimum operating flexibility
and would produce the maximum energy
annually, thereby yielding the best return
on investment. Each of the two pres-sure-
reduction turbines is the approximate
size of an automobile and each is enclosed
by a 20’ by 10’ pre-fabricated sheet metal
building. The turbines are situated about
30 feet from the PRVs.
The hydro turbines essentially operate
as SCADA-controlled PRVs used to gen-erate
They are set up for level-control op-eration
and operate when the on-site 21
million gallon reservoir calls for water.
The turbines produce a constant rate of
flow and shut down when the reservoir
is full. The hydro turbines were installed
parallel to the existing PRVs so that in the
event of a power outage or emergency
situation, the turbine-generators could be
bypassed and water delivery will continue
The total cost of the project was $830,000.
SJWC qualified for $220,000 in Federal stim-ulus
funds (Section 1603 of the 2009 Ameri-can
Recovery & Reinvestment Act), and the
rebate helped lower the payback period to
seven years. Additionally since the water
flowing through Cox Station is used for do-mestic
consumption, the project also quali-fied
for a conduit exemption under the Fed-eral
Energy Regulation Committee (FERC)
jurisdiction. SOAR negotiated interconnec-tion
and power purchase agreements with
Pacific Gas and Electric (PG&E) on behalf
of SJWC that call for selling all energy and
renewable energy credits from the project to
PG&E at an average rate of $0.15/kWh, the
average rate PG&E charges for pumping sta-tions
in northern California).
Since its commissioning in Decem-ber
2011, the project has been generating
572,000 kWh per year of clean renewable
energy. The energy generation and environ-mental
benefit is entirely the result of recov-ering
energy, which was previously wasted
in the PRVs. The project has also reduced
SJWC’s annual operating costs by $86,000,
which it has been able to pass through to
its customers in the form of lower rates. The
utility is currently working on other conduit
hydropower projects to further reduce their
energy consumption. S
along the way...
Utility Service Co., Inc. has proudly served
the potable and industrial water industries
for over 50 years. Today’s Utility Service Group
provides comprehensive condition assessments,
rehabilitation services and sustainable asset management
solutions throughout the whole water cycle.
Call us to discover how our sustainable and unique
solutions can assist you in improving the management of
your water system.
••• ••••••• •• ••
Clean. Safe. Sustainable.
Northern Nevada & California Counties
Kevin Barnes | 916-342-2886
Southern Nevada Counties
Jack Powell| 951-440-7026
Southern California Counties
Keith Myers | 916-869-4464