R2010-107 - 2010-08-09RESOLUTION NO. R2010 -107
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF PEARLAND,
TEXAS, APPROVING CHANGE ORDER NO. 1 ASSOCIATED WITH THE
ALICE STREET WATER PLANT.
BE IT RESOLVED BY THE CITY COUNCIL OF THE CITY OF PEARLAND, TEXAS:
Section 1 That Change Order No.1 associated with the Alice Street Water Plant,
a copy of which is attached hereto as Exhibit "A" and made a part hereof for all purposes,
is hereby authorized and approved.
Section 2 That the City Manager or his designee is hereby authorized to execute
and the City Secretary to attest Change Order No. 1 associated with the Alice Street Water
Plant.
PASSED, APPROVED and ADOPTED this the 9 day of August, A. D., 2010.
T REID
MAYOR
ATTEST:
P Rt V
a, h. cg_
DARRIN M. COKER
Isl>fr/= ra to] :4►IIw'1
APPROVED AS TO FORM:
Exhibit "A"
Resolution No. R2010 -107
CITY OF PEARLAND
PROJECTS DEPARTMENT
3519 Liberty Drive, Suite 300
Pearland, Texas 77581
www.cityofpeariand.com /projects
CHANGE ORDER
For Alice Street Water Plant
Date of Issuance:
Contractor:
Designer:
7/22/2010
Industrial TX Corp.
Camp Dresser McKee, Inc.
Change Order No.:
CoP Project No.:
P.O. No.:
W42051
102315
I
Explanation:
This change order encompasses the following:
The item description and unit price of item no. 13 have been revised to only include items related to the
construction of the facilities required for the pressure reduction facility and not the reverse pump turbine driven
generator.
Delete Specification No. 11300 Reverse Pump Turbine Driven Generator and Accessories and replace with the
attached revised Specification No. 11300. The specification has been modified to incorporate changes
recommended by the turbine manufacturer.
Add Item Nos. 15 through 20. The addition of these items are for furnishing and installing the Hydro Electric
Turbines. All labor, materials and record keeping associated with item numbers 15 through 20 must adhere to
Buy American and the Davis Bacon Labor Regulations.
Add Item Nos. 21 through 23. The addition of these items are for furnishing the pressure reducing valves required
for the project. These items are for the materials. The installation of these items is incorporated in the revised
item no. 13.
Description of Work
Cost
Time
1 Revise Base Bid Item No. 13 as follows: "Furnish, Install and
Construct Pressure Reducing facility Building, Catwalk,
Electrical, 20 and 30" Piping, Valves and all Appurtenances
(original unit price $250,000, revised unit price $192,500)
(57,500.00)
0 Days
Hydro Electric Turbine Items
2 Add Base Bid Item No. 15, "Hydro Electric Turbine
Generator"
315,800.00
0 Days
3 Add Base Bid Item No. 16, "12 -Inch Flanged Bali Valve with
Hydraulic Actuator
117,000.00
0 Days
4 Add Base Bid Item No. 17, "12 -Inch Flanged Gate Valves"
4,360.00
0 Days
5 Add Base Bid Item No. 18, "8 -Inch Flanged Pressure Relief
Valves"
10,650.00
0 Days
6 Add Base Bid Item No. 19, "Piping, Flanges, Fittings, Pipe
Supports and items directly related to the installation of the (2)
two turbines
32,000.00
0 Days
Construction I of 2 D 19. Revised 7108
CITY OF PEARLAND
PROJECTS DEPARTMENT
3519 Liberty Drive, Suite 300
Pearland, Texas 77581
www.cityofpearland.com/projects
CHANGE ORDER
For Alice Street Water Plant
Date of Issuance:
Contractor:
Designer:
Change Order No.:
I
CoP Project No.:
W42051
P.O. No.:
102315
25,500.00
0 Days
88,400.00
0 Days
22,600.00
0 Days
85,750.00
0 Days
Cost
Time
6,846,000.00
390 Days
Days
6,846,000.00
390 Days
644,560.00
0 Days
7,490,560.00
390 Days
7/22/2010
Industrial TX Corp.
Camp Dresser McKee, Inc.
7 Add Base Bid Item No. 20, "Electrical directly related to the
installation and operation of the (2) two turbines"
Additional Water Plant Required Items
8 Add Base Bid Item No. 21, "20 -Inch Sleeve Valve"
9 Add Base Bid Item No. 22, "30 -Inch MJ Gate Valve"
10 Add Base Bid Item No. 23, "20 -Inch Flanged Ball Valve with
Hydraulic Actuator"
Please attach back -up documentation
Cost Time Change Summat
Original Contract:
Previous Change Order(s):
Contract prior to this change order:
Net increase (decrease) from this change order
Revised Contract:
Finance Approval: Lut,� LL�L,� Date: I. au i�
RECOMMENDED:
B Date:
y:
Design Engi er
ACCEPTED
B N: Date: `7 ,V? t o
contractor
RECOMMENDED:
By: Date:
of tt ti t Manager
APPROVED:
By: Date
Owner Bill Eisen,City
zw
08 -09 -2010
Manager
*Contractor agrees to perform change(s) included in this Change Order for the price and time indicated. The prices for changes included all costs associated
with this Change Order.
No work is to be done until this change order is executed. No payment to the Contractor (or Consultant) shall he made for work included in the change order
until the Contractors pay estimate is updated.
Revise the project plans and specifications as referenced and insofar as the original project drawings and specifications are inconsistent. this Change Order
governs. Upon execution by all parties, the following changes identified for the contract value and/or contract time shown, are made part of the contract.
Construction 2 of 2 1719. Revised 7108
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a
Alice Street Water Plant
RFP No.1
Attachment"A"
•
Required for Hydro Electric Turbine
Only the items directly related to the two Turbines which include the 8-inch piping and
12-inch piping. Does not include the 30-inch piping,20-inch piping or building facility.
All labor,materials and record keeping associated with items 15 through 20 must adhere
to Buy American and the Davis Bacon Labor Regulations.
Item Equipment Quantity Unit Unit Price Total
No.
15. Hydro-Electric Turbine 2
Generator Each 5-7,g00 31S, 800
16. 12-Inch Flanged Ball Valve 2 Each
with Hydraulic Actuator S 8,Soo E j 1 ao o
17. 12-Inch Flanged Gate Valves 2 Each z f 8 to '{1 3 bo
18. 8-Inch Flanged Pressure Relief 2 Each
Valves 5, 3z.S J!) (PSD
19. Piping,Flanges,Fittings,Pipe 1 LS
Supports and items directly
related to the installation of the Zt a o 0 3 Zr c o o
(2)Two Turbines
20. Electrical directly related to 1 LS
the installation and operation
- of the(2)Two Turbines ZSi 500 ZSi coEt
Subtotal Hydro Electric Required Items$ 5 0 5I 3 i
Additional Items Required for Water Plant Operation Independent of the Turbine Facility
Item Equipment Quantity Unit Unit Price Total
No.
21. 20-Inch Sleeve Valve 1 Each $8 4o 0 9$ tt oD
22. 30-Inch MI Gate Valve I Each z2j boo 2.2 (000
23. 20-Inch Flanged Ball Valve 1 Each
with Hydraulic Actuator 85 "1 Sa
Subtotal Additional Water Plant Required Items$ t 9 to 1 1 S o
Revise Original Contract Bid Item No. 13
*Item No.13 Quantity Unit Original Unit Revised Unit Total
Price Price Amount
Furnish,Install and 1 LS $250,000 (Deduct)
Construct Pressure 19 21 S o 4 (571 Sob
Reducing Facility
Building,Catwalk,
Electrical,20"and 30"
Piping,Valves and all
Appurtenances
*Item No. 13 was part of the original bid and included all piping and installation
associated with the Turbine Facility including items which are also required for the water
plant facility&pressure reduction(RFP Items 21,22&23). The revised unit price
should not include any costs directly associated with the installation ofthe turbines. The
revised Item No.13 should be the original bid amount$250,000 minus change order
items 19&20(shown above).
Hydro-Electric Turbine Generator price(Item 15)is based on Canyon Hydro(turbine
manufacturer)standard product as discussed between Canyon Hydro and CDM. The
equipment would be the same as originally bid by Industrial Tx with the following
modifications.
• One year warranty
• Manufacturer standard coatings
• Use the manufacturer standard payment terms. Payment terms are 10%down
payment to begin final design,40%payment to release equipment for order and
manufacture,balance due prior to shipment
• Delivery time of 16 weeks from receipt of release for manufacturer payment
• Standard spare parts
• Standard NEMA 12 painted control panels
• Standard NEMA rated indoor painted MCC
• Standard screw type terminal blocks without ring tongue lugs
• One control panel for both units with one MCC panel,UL labeled
• No allowance made for sending two people for retesting of equipment(if needed)
• Turbine built with standard materials
• Induction generator supplied without RTD's in the windings. A temperature snap
switch can be supplied if needed.
• Induction generator will be standard motor construction for that size and class of
motor
• Induction generator will be supplied with mechanical vibration switch
CDM
TBPE Firm Registration No. F-3043
Memorandum
To: Teresa Battenfield, P.E.
From: Kim Chanslor, P.E.
Date: July 29, 2010
Subject: Updated Alice Street Pump Station Turbine Procurement
Purpose
The purpose of this Technical Memorandum is to update the energy recovery feasibility study
prepared for the City of Pearland in April of 2008 utilizing current bidding information and
discuss potential specification modifications to reduce the equipment cost from the
procurement bid received June 17,2010 and provide a recommendation on further action on
the turbine procurement package.
Project Description
The ultimate inflow from the City of Houston at the point where Pearland is beginning their
water line construction is anticipated to be a maximum flow of 15 MGD at 84 psi of pressure.
This flow is anticipated to increase in phases with a starting flow of 4 MGD. The flow will
discharge into the 5 million gallon capacity tank at the inflow elevation of 42 feet above the
ground surface. From the storage tank,the water will flow into a pump station where one of
4 distribution pumps will send it out to the distribution system.
The inflow pressure of 84 psi(or 194 feet of head)greatly exceeds the required 42 feet
pressure at the tank with any headloss from the transmission line. In order to protect the
integrity of the tank and discharge system,the flow from the transmission line must be
reduced (through a pressure reducer)to 18 psi before entering the tank without damaging the
tank or piping. As a way to reduce this pressure as well as recover the energy lost in the
pressure reducer,an energy-recovery hydro-electric turbine was proposed to be inline with
the transmission line prior to the ground storage tank.
Hydraulic Analysis
The final flow expected to enter the Pearland transmission line will fluctuate between 10
MGD and 15 MGD depending on the demand from the distribution system. In the beginning
of the system installation,however,the flow is expected to average around 4 MGD. In the
future,the average flow is expected to reach 8 MGD and will slowly ramp up to the
maximum capacity of 15 MGD.
Due to these large fluctuations in flow,the hydro-electric turbine facility was designed with a
bypass valve to control the inflow to the turbine as well as flow to the ground storage tank.
P.\63916-Pearlend\62916 Alice Street Pump Slalion\4.0 Bidding Phase\072910-Alice Street Pump Station Turbine Procurement.doc 7/30/10 kmc
Teresa Battenfield,P.E.
July 29,2010
Page 2
The turbine bypass line is capable of carrying the full 15 MGD flow into the tank in the event
the turbines are being serviced or are out of order. The turbine bypass line will be equipped
with a sleeve valve to dissipate energy,control flow,and can operate within the cavitation
range of this system. The 20-inch sleeve valve and 20-inch ball valve provided in the design
would be required and included as part of CDM's design even without the addition of the
turbine.
With the previously mentioned large flow changes,a feasibility analysis was completed
assuming separate design conditions of 4 MGD to 15 MGD. The 4 MGD analysis represents
the conditions just after the plant is put into operation. The 8 MGD represents the average
flow between start up (4 MGD) and maximum capacity(10MGD).The 15 MGD represents the
maximum flow in the future phase of the project.
Proposed Design Modifications
Based on the vendor and the turbine manufacturer,Canyon Hydro,comments received
during and after the bid opening several changes to the turbine specification are
recommended to reduce the cost of the hydro-electric turbine and energy generator making it
a standard product supplied by the manufacturer. The manufacturer believes that their
standard product will sufficiently meet the design requirements for this project. The
equipment would be the same as is currently specified,but without modifications or special
provisions. The following are the changes recommended in order to reduce the cost of the
hydro-electric turbine and energy generator equipment.
• Use the standard one year warranty
• Use the manufacturer's standard pay as you go payment terms to avoid the financing by
the manufacturer
• Use manufacturer standard coatings
• Delivery time of 16 weeks from receipt of release for manufacturer payment.
• Payment terms: 10% down payment to begin final design,40% payment to release
equipment for order and manufacture,balance due prior to shipment
• Standard spare parts
• Standard NEMA 12 painted control panels
• Standard NEMA rated indoor painted motor control panels(MCC)
• Standard screw type terminal blocks without ring tongue lugs
• One control panel for both units with one MCC panel,UL labeled
P.163918-Peerlend\62916 Alice Street Pump Station\4.0 Bidding Phese1072910-Alice Street Pump Station Turbine Procurement.doc 7/30/10 kmc
Teresa Battenfield,P.E.
July 29,2010
Page 3
• No allowance made for sending two people for retesting of the equipment(if needed)
• Turbine built with standard materials
• Induction generator supplied without RTDs in the windings. A temperature snap switch
can be supplied if needed.
• Induction generator will be standard motor construction for that size and class of motor
• Induction generator will be supplied with mechanical vibration switch.
• Items addressed by the contractor including the bond and special storage of the equipment
Cost Estimate
The cost estimate to add the required equipment related to the turbine installation into the
existing Alice Street Water Plant Contract is shown in Table 1. The cost reflects the design
and terms and conditions modifications included above reflecting a reduction in the total cost
of the hydro-electric turbine generator of approximately$185,000.00. This$185,000.00 cost
savings is a number provided by both the manufacturer and the contractor to install the
equipment. Also,included is a cost reduction associated with the sleeve valve bid from
Bailey Valve,Inc. Based on discussions with Bailey Valve,Inc.,they are comfortable with the
bid number submitted and can supply an approved equal to the valve quoted in the
Industrial TX bid.This cost only reflects the turbine specific equipment required and does not
include additional equipment required to operate the plant without the turbine as part of the
Alice Street Water Plant Project. Table 1 shows a total capital cost of the addition of turbine
equipment of$505,310.00.
P\63918-Peerlend\62916 Moe Street Pump Station14.0 Bidding Phese\072910-Alice Street Pump Station Turbine Procurement.doc 7/30/10 lent
Teresa Battenfield,P.E.
July 29,2010
Page 4
Turbine Specific Equipment Cost
2 Hydro Electric Turbine Generators with $315,800.00
Controls
2 each 12-inch flanged ball valves with $117,000.00
hydraulic actuator
2 each 12-inch flanged gate valves $4,360.00
2 each 8-inch flanged pressure relief valves $10,650.00
Piping, Flanges, Fittings, Pipe Supports and
items directly related to installation of the 2 $32,000.00
turbines
Electrical directly related to the installation $25,500.00
and operation of the 2 turbines
Total Cost $505,310.00
Table 1
Addition of Turbine Capital Cost
The cost estimate to exclude the turbine from the Alice Street Water Plant Project and add the
required equipment to supply a bypass line in place of the two turbine bypasses is outlined in
Table 2. Table 2 shows an additional total capital cost of the required additions of
$299,325.00.
Additional Equipment Cost
Add 30-inch bypass upstream of the 30-inch
gate valve that includes ball valve and $271,485.00
sleeve valve
Slab extension to accommodate bypass line $17,840.00
Add electrical to new 20-inch ball valve and $10,000.00
sleeve valve
Total Cost $299,325.00
Table 2
Additional Equipment Required Without Turbine
The differential of the two cost estimates presented above of$206,000.00 represents the
additional cost required to add the turbine and related equipment into the Alice Street Water
P.163918-Pearlend\62916 Alice Street Pump Stellon\4.0 Bidding Phase1072910-Alice Street Pump Station Turbine Procurement.doc 7/30/10 loon
Teresa Battenfield,P.E.
July 29,2010
Page 5
Plant Project. This additional cost will be used in the economic analysis below to evaluate the
benefit of the energy cost savings provided by the two turbines versus the capital and
estimated operation and maintenance costs of adding the turbines into the Alice Street Water
Plant Project.
Energy Recovery Analysis
In order to determine whether the updated hydro-electric turbine energy generator project
design is economically feasible,approximate conditions are assumed based on the Canyon
Hydro: Cornell Model 6TR4 reverse pump turbine with 56-KW induction generator or
approved equal as included in the turbine facility design.
The turbine's recovery capabilities are dependent on:
• Flow;
• Pressure or available head;and
• Estimated turbine efficiency.
The economical feasibility is determined based on:
• Construction cost estimate for the installation and purchase of the turbine and required
valves;
• Estimated turbine planning period of 25 years;which is very conservative;
• Estimated operation and maintenance cost of the turbine over a 25 year life span of$3,000
per year;and
• Potential electrical cost savings produced by the turbine.
Cost savings were calculated based on the current electrical rate paid by the City of Pearland
at$0.0837/kWh. It was also assumed that the distribution pumps would need to operate
continuously and therefore would always benefit from the additional power produced from
the turbine. For this analysis,the pump station electrical load was estimated at 1 MW and
would therefore always require additional power in excess of the turbines expected output.
Two hydro-electric turbine generator units were selected for energy recovery at the Alice
Street Water Plant power station. The turbines were analyzed at all flow conditions. This
assumes that the pumping station operates at the selected continuous flow all year. The
following table shows the wattage output, annual savings,and years to recover the cost based
on the additional cost required to add the turbine and related equipment into the Alice Street
Water Plant Project.
P;163918-Peerland\62916 Alice Street Pump Stetlon\4.0 Bidding Phase\072910-Alice Street Pump Station Turbine Procurement.doc 7/30/10 kmc
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July 29,2010
Page 6
Average`
ENERGY RECOVERED ANNUAL SAVINGS Annual
Operation RECOVERY
PUMPING Turbine Turbine Annual. Annual Maintenance (Straight .`-
STATION Unit 1 Unit 2 Total Energy Energy Cost Dollars)
FLOW Power . Power Power Recovered - ,:Savings
(mgd) (kW) - '(kW) (kW) (kWh) -;; ($/year) -. ($/year) . (years)
1 0 $ - $3,000 0
2 0 $ - $3,000 0
3 0 $ - $3,000 0
4 47.4 47.4 415366 $31,766 $3,000 6
5 45.2 45.2 396088 $30,153 $3,000 7
6 43.8 43.8 383819 $29,126 $3,000 7
7 41.9 41.9 367170 $27,732 $3,000 7
8 39.9 39.9 79.7 698411 $55,457 $3,000 4
9 36.9 36.9 73.8 646709 $51,130 $3,000 4
10 33.9 33.9 67.8 594131 $46,729 $3,000 4
11 31.4 31.4 62.8 550316 $43,061 $3,000 5
12 27.4 27.4 54.8 480212 $37,194 $3,000 6
13 23.7 23.7 47.4 415366 $31,766 $3,000 6
14 18 18 36 315468 $23,405 $3,000 9
15 0 $ - $3,000 0
Table 3
Energy Recovery,Annual Savings,and Recovery Period
In order to maximize the energy recovery and payback it is anticipated that the average flow
through the turbine facility during the first five years of operation would be 4 MGD. After
five years of operation,it is anticipated that the average flow through the turbine facility will
be 8 MGD. Assuming a 25 year planning period and energy costs remaining at$0.0837/KWh
the total energy recovered would be 16,045,050 KWh and the total cost savings would be
$1,267,970.00 including estimated operation and maintenance cost expended. This represents
approximately a 6 year recovery period in straight dollars using the differential cost of adding
the turbine of$206,000.00 .
P:\63918-Pearland\62916 Alice Street Pump Station\4.0 Bidding Phase\072910-Alice Street Pump Station Turbine Procurement.doc 7/30/10 kmc
Teresa Battenfield,P.E.
July 29,2010
Page 7
Present Worth Analysis
A present worth analysis was conducted on the anticipated scenario presented above
assuming that the average flow through the turbine facility during the first five years of
operation would be 4 MGD and after 5 years of operation the average flow would be 8 MGD
throughout the 25 year planning period. Considering the annual energy savings as a one time
payment each year during the first 5 years invested an 8% annually the present work savings
is as follows:
Present Worth Annuity Factor(5years) =3.992710
Present Worth(4 MGD,5 years) =Present Worth Annuity Factor x Annual Energy Savings
Present Worth(4 MGD,5 years) =$126,833.00-which represents dollars at the end of the first
5 years of operating at 4 MGD
Assuming the energy recovery savings for the first 5 years is invested with compound interest
during the following 20 years in the planning period. The present worth of that money
invested at an annual interest rate of 8 % is as follows:
Compounding Factor(20 years) =4.660957
Payout After 20 Years,4MGD Savings =Present Worth(4MGD,5Years) x Compounding
Factor(20Years)
Payout After 20 Years,4MGD Savings =$591,163.00-which represents dollars at the end of
the 25 year planning period for 4 MGD operation
Considering the annual savings as a one-time payment each year during the next 20 years
invested at 8% annually,the present worth savings is as follows:
Present Worth Annuity Factor(20 years) =9.818147
Present Worth(8 MGD,20 years) =Present Worth Annuity Factor x Annual Energy Savings
Present Worth(8 MGD,20 years)=$544,503.00-which represents dollars at the end of the 25
years planning period for 8 MGD operation for the last 20 years
The total present worth is as follows:
Total Present Worth=Present Worth(8 MGD,20 years) + Payout After 20 Years,4MGD
Savings
Total Present Worth=$1,135,666.00
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Teresa Battenfield,P.E.
July 29,2010
Page 8
The total present worth of$1,135,666.00 represents the payback amount for a 25 years
planning period. When compared to the differential cost of adding the turbine of$206,000.00
this represents a favorable cost benefit ratio of 5.5 indicating that the project is a very good
economic investment.
ARRA Grant Funds
The City of Pearland received a$685,900 energy grant through the American Reinvestment
and Recovery Act(ARRA)-Energy Efficiency and Conservation Block Grant Program.
$411,500 is allocated for execution of the On-site Renewable Energy project which involves
the purchase and installation of energy-producing turbines at our Alice Street Water Plant.
The Alice Street Water Plant Turbine Project was initially chosen as a feasible project for this
grant money. The ARRA grant funds have many federal restrictions on labor compliance and
origin of equipment attached to the money that the project must adhere to including Buy
American,Davis Bacon Labor Regulations,and NEPA. After the July 1,2010 meeting with
the Department of Energy,the DOE indicated that because the project must be a standalone
project and because the Turbine Project and the Alice Street Water Plant Project are
interrelated,all federal regulations attached to the grant funds must apply to the complete
Alice Street Water Plant Project. These requirements were not included in the current
contract for the construction of the Alice Street Water Plant. These requirements would be
expected to add a significant amount of money to the Alice Street Water Plant Project.
However,it is the opinion of the Engineer that the turbine project is a standalone project. The
following discussion was developed to present the stand alone project case.
The turbine energy generation facility will be installed and operated at the existing/expanded
Alice Street Water Plant. This turbine facility is a separate project from the Plant construction
project because the Plant can operate with or without the turbine facility. The turbine facility
aspect is an added benefit to the combined projects but is not essential to the overall purpose
and/or operation of the Alice Street Water Plant. The Plant Project was a planned Capital
Improvement Project within the City of Pearland and during the preliminary design analysis,
the potential energy generation benefit was discovered because of a regulatory design
requirement with a water system interconnect between the City of Pearland and the City of
Houston.
The Texas Commission on Environmental Quality requires a separation between the City of
Houston's water system and the City of Pearland's water system before the water is pumped
to the City of Pearland's water distribution system. This requirement essentially requires re-
pumping the water and the separation is typically accomplished utilizing an air gap. To meet
the air gap requirement,separating the City of Houston's water system from the City of
Pearland's,the water will go to the ground storage tank at the Plant prior to being pumped
into the City of Pearland's water distribution system. The inflow from the City of Houston at
the point where the City of Pearland is beginning their 30"water line construction is expected
to allow for a flow of 15 MGD at a pressure of 84 psi. The inflow pressure of 84 psi(or 194
feet of head) greatly exceeds the required 42 feet of head at the tank with any head loss from
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Teresa Battenfield,P.E.
July 29,2010
Page 9
the 30"waterline. In order to protect the integrity of the tank and discharge system,the flow
from the 30"waterline must be reduced(through a pressure reducing valve or by other
means)to a maximum of 18 psi.There will be excess head that needs to be dissipated prior to
entering the ground storage tanks and below I have listed a couple of methods on how this
could be accomplished.
Method 1
Method 1 would provide a sleeve valve with a hydraulically actuated ball valve upstream
and a bypass sleeve valve to dissipate pressure while still handling the throttling
requirements of the system to control surge conditions. All valves would be installed within
a building to protect the expensive equipment required at this pressure reducing station.
Method 2
Method 2 would involve the installation of a hydroelectric turbine and energy generator. As
a way to reduce this pressure as well as recover the energy lost in the required sleeve valve,
the City of Pearland is proposing two energy-recovery hydro electric turbines and required
upstream valves to be in line with the transmission line prior to the ground storage tank. The
turbine facility is a"stand alone"project to the Alice Street Water Plant project as the Plant
could and will operate and serve its intended purpose without the installation of the turbine
facility equipment. Additionally the turbine facility equipment could be installed at a later
date as a future project at the plant site.
The City submitted a request for re-evaluation of the project presenting the above case on
July,21,2010 and is waiting for a determination from the DOE.
It is recommended that the Alice Street Water Turbine Project by included as part of the Alice
Street Water Plant Project regardless of the grant determination. As presented above it is a
economically viable project even without the grant funding.
Overall Recommendations
Based on the terms and terms and conditions changes and design changes that bring the
turbine facility differential cost estimate at$206,000 versus not including the turbine and
based on the present worth and recovery period analysis presented in this memorandum it is
recommended that the turbine facility be included in the Alice Street Water Plant construction
contract through a negotiated charge order. The payback and economic factors are very
favorable and well within the conservative planning period illustrating that the turbine
facility project is not only a future cost savings to the City,but an innovative and show case
project for the City.
cc: Chris Canonico,P.E.
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