improving the climate resilience of tajikistan’s hydropower sector

Improving the climate resilience of Tajikistan’s hydropower sector

Rob Wilby Loughborough University

Michael FriedhoffSKM

Richenda Connel & Ben RabbAcclimatise

Nasridin Minikulov, Anvar Homidov, Muzaffar ShodmanovTajik Hydromet

Nadezhda LeonidovaLoiha-Gidroenergo

PPCR Workshop on Climate Resilience and the Energy Sector6-7 March 2012, Barki Tojik, Dushanbe, Tajikistan

Kairakkum power station and spillway, downstream view


Overall objectives of PPCR Phase I (A4)

Two main objectives:

#1. Analyze the climate vulnerability of Tajikistan’s hydropower sector;

#2. Recommend ways in which the analysis can inform investment planning, including use of Phase II PPCR resources to support specific adaptation activities leading to a more climate-resilient hydropower sector.

Kairakkum reservoir 2012


Orientation – Kairakkum


Orientation – Nurek


Main tasks of PPCR Phase I (A4)

Six activities:

#1. Assemble and analyze historic hydro-climate trends

#2. Produce a synthesis of regional climate scenarios

#3. Develop hydrological models to evaluate impacts

#4. Review climate alongside other natural hazards

#5. Evaluate potential scenarios for hydropower

#6. Identify options to build resilience to climate change


Analytical frameworkClimate change

scenariosHydrological modelsREG WBM SRM

Upstream river regulation

Monthly/annualflow factors

Monthly/annualevaporation

Hazardsanalysis

Reservoirsafety

Reservoirwater balance

Energy production

model

Refurbishment and upgrade scenarios

Operatingrule scenario

Sedimentation data


Activity #1 – Data assembly and trend analysis

0

1000

2000

3000

4000

5000

1949

1951

1953

1955

1957

1959

1961

1963

1965

1967

1969

1971

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

2009

Ann

ual m

axim

um d

isch

arge

(m

3/s) Aqjar Darband


Example data sources

0

20

40

60

80

100

120

140

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010P

reci

pit

atio

n t

ota

l (m

m)

GPCC-1.0deg

TRMM-0.25deg

SDSM-M20


y = 0.0124x - 24.569R² = 0.0756

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

1960 1970 1980 1990 2000 2010

Ann

ual t

empe

ratu

re a

nom

aly

(°C

)

NarynT

y = 0.6043x - 1092.4R² = 0.0509

0

50

100

150

200

250

1960 1970 1980 1990 2000 2010

Ann

ual p

reci

pita

tion

(%

LTA

)

KhujandP

y = 0.9804x - 1833.8R² = 0.2026

0

50

100

150

200

250

1960 1970 1980 1990 2000 2010

Ann

ual d

isch

arge

(%

LTA

)

AqjarQ

y = -0.001x + 1.8565R² = 0.0004

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

2.0

1960 1970 1980 1990 2000 2010

Ann

ual t

empe

ratu

re a

nom

aly

(°C

)

LayhshT

y = 0.6322x - 1148.1R² = 0.1142

0

50

100

150

200

250

1960 1970 1980 1990 2000 2010

Ann

ual p

reci

pita

tion

(%

LTA

)LayhshP

y = -0.015x + 129.8R² = 0.0003

0

50

100

150

200

250

1960 1970 1980 1990 2000 2010

Ann

ual d

isch

arge

(%

LTA

)

DarbandQ

Observed trends in annual mean temperature [T], precipitation [P] and discharge [Q] for Kairakkum (top row) and Nurek (lower row) relative to the 1961-1990 mean. The red dashed line for Khujand shows a hindcast of the Tropical Rainfall Measuring Mission (TRMM) area-average precipitation for the upper Syr Darya basin.

Local hydro-climatic trends


0.0

0.2

0.4

0.6

0.8

1.0

16-Mar 16-Apr 16-May 16-Jun 16-Jul 16-Aug 16-Sep

Frac

tion

of

zone

tha

t is

sno

w c

over

ed Zone 1

Zone 2

Zone 3

Zone 4

Zone 5

Zone 6

Zone 7

Zone 8

Snow-cover duration curves (CDCs) for the upper Vakhsh basin in 2010

Snow cover


Activity #2 – Climate change scenarios

Temperature and precipitation changes over Asia from the MMD-A1B simulations.

Source: Christensen et al. (2007).


0

1

2

3

4

5

6

7

-20 -10 0 10 20 30 40

Tem

pera

ture

chan

ge (°C

)

Precipitation change (%)

Naryn 2050s

A2

A1B

B1

Mean

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1

2

3

4

5

6

7

-20 -10 0 10 20 30 40

Tem

pera

ture

chan

ge (°C

)


Naryn 2080s

A2

A1B

B1

Mean

0

1

2

3

4

5

6

7

-20 -10 0 10 20 30 40

Tem

pera

ture

chan

ge (°C

)


Layhsh 2050s

A2

A1B

B1

Mean

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1

2

3

4

5

6

7

-20 -10 0 10 20 30 40

Tem

pera

ture

chan

ge (°C

)


Layhsh 2080s

A2

A1B

B1

Mean

Regional climate scenarios


Climate change marker scenarios

Marker scenario

2050s 2080s

ΔT ΔP ΔT ΔP

Hot-dryDriest and most rapid warming member(s)

+4°C -10% +6°C -15%

CentralEnsemble mean precipitation and temperature change

+3°C +5% +4°C +5%

Warm-wet

Wettest and least rapid warming member(s)

+1.5°C +20% +2°C +30%


0

0.2

0.4

0.6

0.8

1

0 10 20 30 40 50 60 70

Cum

ulati

ve li

kelih

ood

Annual PE change (%)

2020s 2050s 2080s

Cumulative likelihood distributions of annual PE increases (% change with respect to the 1961-1990 baseline) projected by ensembles of PE estimation method, emission scenario, and GCM output (for the closest grid-points to the Kairakkum reservoir).

Evaporation scenarios


0

1

2

3

4

5

6

7

-20 -15 -10 -5 0 5

Tem

per

atu

re c

han

ge

(deg

C)

Annual mean temperature bias (degC)

A1BA2B1SDSM-A2SDSM-B2

Changes in a mean annual temperature and precipitation for Khujand under different greenhouse gas emissions scenarios for the 2080s

Climate model uncertainty and downscaling


12

12.5

13

13.5

14

14.5

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15.5

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16.5

17

1960 1965 1970 1975 1980 1985 1990 1995 2000

An

nu

al

me

an

te

mp

era

ture

(de

gC

)

SDSM

Observed

-30

-20

-10

0

10

20

30

40

January February March April May June July August September October November December

Mea

n d

aily

tem

per

atu

re (�C

)

Observed (black) and downscaled (red) annual mean temperatures at Khujand

Observed (black) and downscaled (grey) mean daily temperatures at Lyahsh in 1993

Downscaling applications


Activity #3 – Hydrological modelling


Data for hydrological modelling and sensitivity analysis


0

2

4

6

8

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14

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

PE (m

m/d

ay

Month

(B) Potential Evaporation 2020s

minq1medianq3max

0

2

4

6

8

10

12

14


PE (m

m/d

ay

Month

(C) Potential Evaporation 2050s

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8

10

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14


PE (m

m/d

ay

Month

(D) Potential Evaporation 2080s

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2

4

6

8

10

12

14


PE (m

m/d

ay

Month

(A) Potential Evaporation 1961-1990

ThornthwaiteBlarney-CriddleHamonMass balance

Estimated PE for 1961-1990 based the Thornthwaite, Blaney-Criddle and Hamon methods and observed temperatures. PE estimates from the mass balance of the Kairakkum reservoir are also shown

Evaporation modelling


Observed (grey line) and REG modeled (black lines) annual discharge at Aqjar for 1955-2010. The plot also shows projected discharge for the 2050s under the three climate change scenarios (colored lines)

1. Regression model

200

300

400

500

600

700

800

900

1000

1100

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Aqj

ar a

nnua

l m

ean

Q (m

3/s)

OBSERVED BASELINE (NO FILL) BASELINE (FILLING)

HOT/DRY WARM/WET ENSEMBLE MEAN


2. Water balance model

Q = (A.P.k) + (G.ΔT) – (A.E) ± S ± D

Q is the discharge (km3),

A is the basin area (km2),

P is the annual precipitation (km),

k is a scaling factor,

G is the total snow and glacier melt per year ΔT degree temperature change (km3/yr/°C),

E is the annual evaporation total (km),

S is upstream storage change (km3),

D is diversions for irrigation or effluent (km3).

0

200

400

600

800

1000

1200

1960 1970 1980 1990 2000 2010

Cum

ulati

ve d

isch

arge

(km

3)

Observed Modelled

0

200

400

600

800

1000

1200

1960 1970 1980 1990 2000 2010

Cum

ulati

ve d

isch

arge

(km

3)

Observed Modelled

Syr Darya to Aqjar

Vakhsh to Darband


3. Snowmelt Runoff Model (SRM)

Qn+1 = [CSn · αn (Tn + ΔTn) Sn + CR · Pn] A · v (1 – kn-1) + [Qn · rn+1]

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01 02 03 04 05 06 07 08 09 10 11 12

LapseRate

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01 02 03 04 05 06 07 08 09 10 11 12

Tcrit

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01 02 03 04 05 06 07 08 09 10 11 12

DDF

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1

01 02 03 04 05 06 07 08 09 10 11 12

Cs

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01 02 03 04 05 06 07 08 09 10 11 12

Cr

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01 02 03 04 05 06 07 08 09 10 11 12

RCA

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1200


Mea

n da

ily d

isch

arge

(m

3/s)

Observed SRM

Daily mean composite of observed and SRM discharges at Darband 2001-2010


Activity #4 – Natural hazards analysisRef Date Type Description19 29/2/96 FL Rising level of water on the river of Syr-Darya, destroyed boat bridge

36 16/4/96 FL

Flooded 100 houses, 3 houses are completely destroyed, there are main road washed away 35km, 12 pieces bridges, internal road - 25 km, power line - 3,6 km, coast-protecting structure - 25 km, water collector network - 25 km, water-supply canal - 5km, ?????????? 23 irrigation well and transformer substation, carried away 15 watermill, damaged planted area more than 100 ha, orchard and vineyards about 100 ha, vegetables - 12 ha, foods - 12ha.

93 26/2/97 FL95 3/3/97 WI

112 25/4/97 PR119 11/5/97 PR Destroyed 4 km of road

130 26/5/97 FLWashed away 200 hectares of crops , 52 apartment buildings, a breakthrough 8 km channel at 7 locations, 110 tons of haylage were flooded

131 26/5/97 PR138 11/6/97 PR156 19/7/97 LS Bridge destroyed near the sanatorium Zumrad-2159 19/7/97 PR Destroyed the bridge, the road 500m, the protective structures along rivers, power lines 400m192 27/2/98 PR Washed away dam, flooded farmland196 28/2/98 WI Has damage to households and private individual

Source: Information Management and Analytical Center (IMAC) of Tajikistan. Recorded events near Kairakkum 1992-1998.


05

101520253035404550


Avalanche

05

101520253035404550


Earthquake

05

101520253035404550


Flood

05

101520253035404550


Landslide

05

101520253035404550


Precipitation

05

101520253035404550


Wind

Occurrence of natural hazards in the IMAC data base 1992-1998 (as percentages of their respective total frequencies).

Natural Hazards

1992-1998


Panjakent

Somoniyon

Fayzabad

Rushan

Potential for (some) hazard forecasting

Locations of mudflows and reported flooding 5 to 11 May 2011 compared with TRMM rainfall


Activity #5 – Hydropower scenarios

Kairakkum dam and power station - general arrangement


Changing bathymetry

Storage curves generated from bathymetric survey data were obtained for 1965, 1975 and 2009. Additionally the original storage curve for 1957 is available.


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500

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1500

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3000

3500

Jan

Feb

Mar

Ap

r

May Jun

Jul

Aug

Sep Oct

No

v

Dec

Dai

ly Q

(m

3/s)

2001

Observed

SRM

Hot-dry

Central

Warm-wet

Observed and SRM estimates of daily discharge under present and changed climate scenarios (hot-dry, central, and warm wet) for the 2050s.

Calibration based on 7 snow cover images

Runoff scenarios – Naryn upstream of Toktogul

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500

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3000

3500

Jan

Feb

Mar

Ap

r

May Jun

Jul

Aug

Sep Oct

No

v

Dec

Dai

ly Q

(m

3/s)

2003

Observed

SRM

Hot-dry

Central

Warm-wet


Observed and SRM estimates of daily discharge under present and changed climate scenarios (hot-dry, central, and warm wet) for the 2050s.

Calibration based on 15 snow cover images

Runoff scenarios – Naryn upstream of Toktogul


ScenariosKairakkum on

(discharge at Aqjar)

Nurek on Vakhsh cascade

(discharge at Darband)

2050s ΔT ΔPSRM*

(18%)

REG

(13%)

WBM

(23%)

SRM**

(16%)

SRM*

(16%)

REG

(10%)

WBM

(33%)

Hot-dry +4°C -10% +16 +20 -50 +25 +34 -8 -34

Central +3°C +5% +17 +21 +2 +19 +28 -3 0

Warm-wet +1.5°C +20% +18 +19 +55 +12 +18 +4 +35

2080s ΔT ΔP SRM REG WBM SRM* SRM** REG WBM

Hot-dry +6 °C -15% +27 +30 -80 +51 +55 -12 -55

Central +4 °C +5% +22 +27 -5 +29 +38 -4 -6

Warm-wet +2 °C +30% +28 +28 +83 +20 +25 +6 +51

Summary of runoff scenarios

* Parameters in SRM advanced by 15 days per °C of warming; ** Fixed parameters used in SRM (see Annex 1 for further details).


Syr Darya - Average monthly discharge (m3/s) at Akjar

Regulated inflow regime


Operating rules

Average Kairakkum reservoir level (m) at the beginning of each month


Monthly energy production - calibrated

Actual and modelled monthly energy production at Kairakkum assuming 88% of rated efficiency


Scenarios of firm energy production


Adaptation options (Kairakkum)a) Operational changes

•Use 0.85 m of the flood surcharge volume as live storage (assumes flood peaks are attenuated by Toktogul and Andijan)

•Change operating rules to maximize head and minimize spill

b) Structural/physical changes

•Increase power station capacity to 147 MW by uprating generators and control system

c) Combined approach

•Increase full supply level by 0.5 m and increase power station capacity by 147 MW

d) Other measures

•Heighten the dam

•Integrated management and coordination of upstream dams

•Install additional generating unit


Outcome of adaptation options – wetter future

Annual energy under the REG-Central (+21% flow) scenario for different strategies


#6 Recommendations for building resilience


1) Further analytical work and monitoring

1. Strengthen the hydrometric network

2. Lengthen the period for snow cover measurement

3. Use measured spill and turbine discharge data to improve water balance model

4. Digitize and quality-assure remaining paper-based hydrometeorological records

5. Establish robust protocols for flood safety assessment under changing conditions

6. Examine geo-referenced hazards data for climate signals

7. Assess the feasibility of seasonal forecasting for reservoir operation


2) Training and collaboration

1. Strengthen national capabilities in climate risk assessment through partnership working and exchanges

2. Strengthen data management and record keeping

3. Build collaborative links with international partners in research, engineering and academia

4. Submit PPCR research to international journals for scientific peer review

5. Run technical workshops on climate diagnostics, climate risk assessment, and seasonal forecasting


3) Investments in hydropower facilitiesKairakkum power station options

(a) Use some flood surcharge volume as live storage

(b) Change operating rules to maximize head and minimize spill

(c) Increase power station capacity during planned rehabilitation

(d) Combined approach

(e) Manage sediment loads

Vakhsh cascade options (no data)

(a) Construction of the Rogun dam with associated operating rule changes for Nurek

(b) Increase Nurek power station capacity

(c) Contingency measures for credible warnings of rainfall-triggered landslides

improving the climate resilience of tajikistan’s hydropower sector

Documents

barki tojik

energy sector6

climate changeppcr workshop

review climate

historic hydroclimate

downstream viewppcr

snow coverppcr workshop

trend analysisppcr workshop