20120900 Ver 2_ Linear Cone Valve & DO Presentation_20181127

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Yadkin Linear Cone Valve Operation Overview
November 27th, 20 1 8
W. Neal Simmons, Eli Hopson, Jody Smet
Confidential

Outline
• Dissolved Oxygen Enhancing Technology
• Traditional vs. Proposed
• Improving DO at the Yadkin Project
•
401 Kequire�nents and early compliance
• Linear Cone Valve Installation
• Valve and Sensor Locationsl Information
• Linear Cone Valve Testing
• Data Analysis and Results
• Tune -series analysis
• Dissolved oxygen response
• Seasonal results
• Summary and Next Steps
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Improving Dissolved Oxygen on the Yadkin
• DO levels in High Rock and Tuckertown tailwaters
periodically fall below the State standards during the
summer and fall (May — November)
• Cube Yadkin understands the importance of meeting
water quality standards, including DO
• Investing in R&D and technology to meet standards:
• Direct oxygen injection in penstock and scroll cases
• Central aeration
I-Iowell-hunger Valves
Draft tube aeration
Distributed aeration (GE)
Linear Cone Valves
Advanced controls, measurement, and
prediction
Environmental
Quality
Request NCDEQ to modify condition 12c in the 401 to replace the requirement of the
Howell-Bunger valve with the use of the Linear Cone Valve.
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Traditional Solution
4NY
1V
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Advantages:
• Proven technology
Challenges:
• Reduced dam integrity
• Impact to NRNP eligible facility
• Boat/Fishing safety
• Impacts recreation
• Fatigue failure from jet dynamics
• Long installation time
• Portion of water has limited exposure
to atmosphere, limiting oxygen pickup.
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Alternative Solution (Linear Cone Valve)
Advantages:
• Breaks flow into droplets for exposure to
atmosphere in same manner as a Howell-
Bunger type valve, but provides greater
aeration
• Easily installed on existing spillway gates and
utilizes gate motion and hydrodynamic forces
to adjust valve setting
• Valve can be configured to self -regulate flow
or vary oxygenation
• 20X reduction in installation time
• Safer for downstream recreation
• Maintains integrity of dam
• Preserves historic attributes of facility
Challenges:
• New solution with limited field experience
• Limited to facilities with spillways, such as the
facilities on the Yadkin river
Confidential
Currently installed at High Rock and
Tuckertown facilities
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Linear Cone Valve Operational Flexibility
Concrete SurfaC
Spillway
Video illustrating how the Linear Cone Valve operates (click on ima
Confidential6
e to play).
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Improving Dissolved Oxygen
License Requirements
401 WQC Condition No. 12 outlines required DO enhancements:
• Monitoring & Reporting - Started and Ongoing
• Installation of Upgrades to Generators at High Rock - Started and Ongoing
• Installation of Upgrades at Narrows - Com
pleted
• Installation of Fixed -Cone (Howell-Bunger) at High Rock and Tuckertown — Evaluating
alternative design (Linear Cone Valve) xhich have been installed at both facilities
If planned enhancements do not result in compliance with water quality
standards for DO/temperature, additional measures are required to be
developed in consultation with DEQ.
Implementation
During Generation: Install GE aerating turbines. Upgrade on Unit 1 has begun,
with Units 2 & 3 following. To be completed by September 22, 2020.
No Generation: Continue to operate Linear Cone Valve at High Rock and
Tuckertown (Pending Approval
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Specific Yadkin System Challenges
• Hypereutrophication of
upstream reach complicates
DO mitigation, requiring
increased oxygen enrichment
• Must meet 4.0 mg/L
instantaneous and 5.0 mg/L
average DO standard
• DO enhancement
requirements from May -
November
• Standards must be met during
periods with and without
generation
Confidential
U.I
i
Dissolved Oxygen Fluctuations at Tuckertown Dam
OCI01
Oct 02 Oct 03
Date
Oct 04
2017
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High Rock Linear Cone Valve and Monitoring Setup
Imagery 02016 GoogM, Map data 02016 Google 200 It
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Tuckertown Linear Cone Valve and Monitoring Setup
I
ated Capacity: 38.04MW
Kaplan (12.68 MW)
Imagery 02019 G
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Dissolved Oxygen Floating Sensor Package
Design revised in Fall 2018 to
improve stability and
reliability during high flow
events
C
Provides real-time monitoring of water
temperature and DO
Specifications:
• Installed Sensors
— Dissolved Oxygen
— Temperature
— System Health
• Onboard Power Supply
- Solar powered + batteries
• Communications/Data
— Onboard data storage
— Wireless updates to server every 10
minutes
— Operators can connect to unit to
view live data
Note: Data gathered in accordance with NCDEQ
approved Monitoring Plan and QAPP
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Linear Cone Valve in Operation
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DO Data and Linear Cone Valve Operations Analysis
Linear Cone Valve Installed on Gate #1 at High Rock and Tuckertown,
and began testing on 5/18 and are continuing to evaluate operations at
multiple settings
High Rock: Over 87 days of operational data with statistically
representative number of events for conditions of interest (Generating,
Spilling and Operating Linear Cone Valve)
Tuckertown: Over 33 days of operational data with statistically
representative number of events for conditions of interest (Generating,
Spilling and Operating Linear Cone Valve).
High flow events throughout DO season presented challenges
• DO boats capsized under bypass operations and needed to be recovered for several
high flox events
• Valve performance cannot be tested when by orgenerating because of high
flows through turbines or by gates mute effect from linear cone valve.
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NX
18
> 16
W
0 14
U
.Q
12
U)
X10
N
8
X
X
O
High Rock DO Season Time Series
May 1st - Oct. 16th
40
35
30
2
Ell
Jun Jul Aug Sep Oct
Dissolved Oxygen (mg/L) Spilling Cone Vale Generation (MW)
DO conditions noticeably change with operational conditions, with a consistent rise in
DO when the linear cone valve is opened or while spilling (see slide 16).
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10
1
I

High Rock DO: Linear Cone Valve Not In Operation
July 13th -July 21st
10
9
8
J 7
C
6
a�
CD
a 5
x
O
N
0 4
3
2
1
a
Sunrise
r
Jul 15, 00:00 Jul 15, 66:00 Jul 15, 12:00
i
30
PR
20
C
0
m
Q
E
15 c,
U
5
0
Jul 14 Jul 15 Jul 16 Jul 17 Jul 18 Jul 19 Jul 20 Jul 21
Dissolved Oxygen (mg/L) Spilling Cone Valve Generation (MW)
DO conditions show strong diurnal pattern, decreasing at night when generation is off
(red arrows), DO rise seen after sunrise due to photosynthesis.
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10
9
8
J 7
6
c
a�
0a
X 5
0
N
7
0 4
3
2
1
0
High Rock DO: Linear Cone Valve in Operation
Aug 18 Aug 19
Dissolved Oxygen (mg/L)
August 17th - August 23rd
Aug 20 Aug 21 Aug 22
Spilling Cone Valve Generation (MW)
Bit,
25
20
5
0
Aug 23
DO increases sharply when cone valve is open after generation has stopped. DO levels
continue to increase the longer valve is open as more water in tail race is oxygenated.
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O
18
> 16
CD
12
Q
U)
X10
E
c
N
X
X
O
a 6
(D
0
N
4
a
2
Tuckertown DO Season Time Series
may 151 - VGZ. lot"
0
May Jun Jul
Dissolved Oxygen (mg/L)
Aug
Spilling Cone Valve
Sep
Generation (MW)
Oct
45
40
35
30 2
10
5
Ulm
DO conditions noticeably change with operational conditions, with a consistent rise in DO
when the linear cone valve is open and generation is off, or while spilling (see slide 18).
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10
9
8
7
J
CF)
6
a�
X 5
N
o 4
0
3
2
1
0
Tuckertown Dissolved Oxygen Response to Cone Valve
loin - sept tstn
Valve Off Valve On
F Valve Off —1 F Valve On
Aug 29 Sep 01 Sep 04 Sep 07
Dissolved Oxygen (mg/L) Spilling Gone Vale =Generation (MW)
Elf]
35
30
25
0
0
c
20
i
U
15 0
a
10
5
0
Linear cone valve is very effective at improving DO. When the facility is not generating,
DO increases sharply when cone valve is open (green arrows) and decreases when valve is
closed (red arrows).
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Data Analysis
Approximately 24,000 data points per -channel for
each site were analyzed using Matlab
Linear Cone Valve Performance was evaluated
when generation was off and there was no
spilling. Flows from generation or spilling are
approximately 30x greater than the flow through
valve and therefore dominate the DO readings
Exemplar dissolved oxygen response
Methodology
• Time series were identified when there was no spill and generation was off
• To exclude the effect of photosynthesis only data points from sunset to sunrise were examined
• DO at the beginning of time -series (end of generation) was found (Start DO, point A)
• DO at end of time -series (sunrise or start of generation) was found (End DO, point B)
• Maximum DO reading during series was found (Max DO, point C)
• Minimum DO reading during series was found (Min DO, point D)
• The change in DO was calculated by subtracting the starting DO value from the ending DO value (Delta DO,
points B -A)
• The DO range was calculated by subtracting the minimum DO value from the maximum DO value (Range DO,
points GD)
• Slope of the DO rise was determined by finding the slope of a least-squares fit of a straight line (1St order
polynomial) through the data (DO Slope, green dashed line)
• Values for each of the above parameters were averaged and compared for statistical significance (see table on
slides 20 and 21)
T
,r"
,4
Q
,2 i
ift
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High Rock Data
Dissolved Oxygen Response to Linear Cone Valve
i
J
C�
E 2
0 0
U)
W
Blue Box 25-75 Percentiles '
Red Line Median Value '
Whiskers Data Range
n=19
n=37
OFF Partially Open
Valve Condition
Averages of Time -series Data
Full Open
4
3
E
c:7) 2
C
L
0
-0 0
aD
0
Dissolved Oxygen Response with Time
-2
3 4 5 6 7 8 9
Time Since Generation Ended (hours)
Dissolved Oxygen (mg/L) Slope Valve 1 1 J Delta Linear Cone Valve increases DO by move
Valve Off 4.42 3.65 -0.81 3.33 4.60 1.26 -0.10 than 2 g/L and continues to increase DO
Partially Open 3.03 2.16 -0.87 1.86 3.14 1.28 -0.12 the longev zalze is opened
Open 3.09 5.30 2.25 2.87 5.42 2.56 0.42
See slide 19 for method details
Confidential
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Valve Off
Valve On
/
+
-2
3 4 5 6 7 8 9
Time Since Generation Ended (hours)
Dissolved Oxygen (mg/L) Slope Valve 1 1 J Delta Linear Cone Valve increases DO by move
Valve Off 4.42 3.65 -0.81 3.33 4.60 1.26 -0.10 than 2 g/L and continues to increase DO
Partially Open 3.03 2.16 -0.87 1.86 3.14 1.28 -0.12 the longev zalze is opened
Open 3.09 5.30 2.25 2.87 5.42 2.56 0.42
See slide 19 for method details
Confidential
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Tuckertown Data
Dissolved Oxygen Response to Linear Cone Valve
Blue Box 25-75 Percentiles
3- Red Line Median Value
Whiskers Data Range
2.5-
n=16
E
C: 2-
0)
T
x 1.5-
0
.5-O '
1 - n=17 '
0
uui 0.5-
0
2 0
0
Off Open
Valve Condition
Averages of Time -series Data
3.5
3
J
0 2.5
2
c
ca
0 1.5
C:
a)
°>, 1
X
O
0.5
0
U) 0
-0.5
Dissolved Oxygen Response with Time
+ w Valve Off
+ Valve On
+
+
+
� x
-1
2 3 4 5 6 7 8
Time Since Generation Ended (hours)
jjp� I I Dissolved Oxygen (mg/L) Slope Linear Cone Valve increases DO by more
RangeValve Condition Start End Delta Min. Max. = than 2 nagl L and continues to increase DO
Valve Off 3.30 3.71 0.41 2.95 4.15 1.20 0.08 the Ion ger zalzeis opened
Open 3.50 5.62 2.12 3.28 5.64 2.36 0.36
See slide 19 for method details
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Linear Cone Valve -Early Benefit
Linear Cone Valve
Design Flow
220
cfs
Discharge DO
Fully Saturated
Construction Time
60
days
Water Aerated in 20181
14.22
billion gallons
Dam Safety Impact
None
1 Total of 6.54 billion gallons at High Rock and 7.68 billion
gallons at Tuckertown
Confidential
Howell-Bunger Valve
Design Flow
220
cfs
Discharge DO
Fully Saturated
Construction Time
280
days
Water Aerated in 20182
0
gallons
Dam Safety Impact
Significant
2 No water could have been aerated in 2018 or 2019 because
of long installation time and approval timelines from the final
FERC license_ no loner subiect to anneal
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Addressing Yadkin's DO Requirements
0
GE Aerating Runner
Confidential
Linear Cone Valve
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Summary & Next Steps
Cube Yadkin is implementing a combined solution that addresses both the generation and non -
generation license requirements, while simultaneously accelerating the implementation and
preserving the integrity of the Dam.
The operation of the Linear Cone Valve results in a consistent increase of dissolved oxygen,
demonstrating the system improves DO when turbines are not in operation.
Resultsgathered are equivalent or better than the e.�ectedpeTformance of the required Howell -Bungee zalves
Request NCDEQ to modify condition 12c in the 401 to allow for the use of the Linear
Cone Valve to satisfy the Howell-Bunger cone valve requirement.
Evaluation of
Linear Cone Valve
CHP Acquires DO Season 1
Yadkin (Data Gathering
I
2017
Confidential
Yadkin DO Upgrade Timeline
DO Season 1
(Data Analysis)
2018
DO Season 2
(Data Gathering)
HR Unit 1
Completed
Q1-2 2019
DO Season 2
(Data Analysis)
HR Unit 2
Completed
Q3-4 2019
HR Unit 3 Completed
Sept -2020
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