82nd Annual meeting of ICOLD Bali, Indonesia, June 2nd to 6th, 2014
ICOLD «Ad Hoc Committee on Prospective and Challenges»
(ICOLD Committee on Emerging Challenges and Solutions)
Present and future role of dams & reservoirs
Survey in Vietnam M.Ho Ta Khanh - VNCOLD
1. Hydropower and other forms of electricity production (present and future)
In 2005, the hydropower capacity was 4,200 MW and the hydropower output
was 17 TWh.
The increase in demand in the period 2005-2025 is estimated at 77,466 MW
and anticipated to be covered by the following sources:
Energy source
Increase in
capacity
MW
Increase in
energy
TWh
Average plant
Factor
Hydro 11,759 49.28 0.48
Small Hydro 1,400 4.94 0.40
Pumped Storage 4,200 -2.46
Coal 34,775 196.19 0.65
Gas 12,721 50.18 0.45
Diesel & Oil -485 2.24 0.51
Renewable
Energy 500 1.01 0.23
Nuclear 8,000 53.27 0.76
Import (Hydro) 4,596 24.36 0.61
Total 77,466 379.01
Harnessing of entire hydropower potential in Vietnam will complete in 2017 by various large,
medium and small hydropower plants
2. Electricity: base, intermediate and peak
For the time being, hydropower is mainly used for intermediate and peak loads. In the future, hydropower will still be used for intermediate and peak loads but covering the intermediate load being the dominant.
Distribution of Energy Generation has been assumed as set out in table below
Load
Time
during the
Day
Hours/Day Incremental
Hours/Day
Incremental
Hours/Day
%
Distribution in
Energy Generation
%
Base 0-24 24 6 25 0
Intermediate 6-22 18 12 50 70 (66.7)
Peak 10-12 and
17-19 6 6 25 30 (33.3)
Category Unit 2005 2010 2020
Electricity Generation TWh 53.4 113.0 294.0
Peak Load MW 9,255 20,000 50,000
Installed Capacity MW 11,577 27,000 62,000
3. Hydropower
River Basin Capacity
MW
Generation
TWh
Density
MWh/km2
Share
%
Lo – Gam Chay River 1,120 4.10 212 4.9
Da River 6,960 26.96 1,400 32.3
Ma River 890 3.37 74 4.0
Ca River 520 2.09 147 2.5
Vu Gia – Thu Bon River 1,360 5.10 475 6.1
Tra Khuc – Huong River 480 2.13 531 2.6
Ba River 670 2.7 150 3.2
Se San River 1,980 9.36 700 11.2
Srepok River 700 3.32 143 4.0
Dong Nai River 2,870 11.64 436 14.0
Total of 10 main basins 17,550 70.77 423 84.8
Whole country 20,560 83.42 250 100
• Hydropower potential in Vietnam
Some recent dams (H>30m)
constructed in Vietnam
4. Main large dams in Vietnam (H>30m)
Dam
State River Type HD LD (m) VD VR Area R L R Catchment
area
Spill.
Cap Pu W
Irrigated
Area
(m) (hm³) (hm³) (km²) (km) (km²) (m³/s) (MW) (GWh) (ha)
A VUONG O Vu Gia 80 228 343.55 9.09 5 720 210 815
BAC HA Chay RCC 78 438 171.10 3 465 90 378
BAN CHAT C Nam Mu RCC 125 420 1.65 1.70 220 1 158
BAN VE O Ma RCC 135 509 1.46 1. 83 8 700 14 872 320 1 084
BINH DIEN O Huu Trach 75
BUON TUA SRAH Krong No ER 80 787 86 360
CAN DON O Be ER 45 1 130 78 321 4 800
CO BI 70
CUA DAT O Chu CFRD 118 930 1 364 5 938 11 594 97 42 500
DA MI O La Nga ER 69 490 2.96 141 6.3 3 83 658 175 580 30
DA NHIM O Da Nhim E 38 1 460 3.60 165 9.3 4 775 4 500 160 1 026
DAI NINH O 54
DAKDRINH Dakdrinh RCC 94 249.3 9.12 420 125 521
DINH BINH O Kon 55 0.43 226 15 500
DONG NAI 3 O Dong Nai RCC 108 586 1 423. 6 56 2 441 180 595
DONG NAI 4 O Dong Nai RCC 128 509 1.50 337.2 8.5 149 340 1 010
HAM THUAN O La Nga ER 94 686 3.85 695 25.16 12 1 280 4 200 300 965 550
HOA BINH O Da ER 128 734 22.7 9 870 217 230 51 700 37 800 1 920 8 160
HUA NA O RCC 94.5 180 717
HUOI QUANG C RCC 104 267 0.937 184.2 8.7 2 824 12 908 520 1 094
KRONG BUK HA C E 33 2 293 110 11 800
LAI CHAU C Da RCC 137 1 215 26 000 1200 4 671
LONG SONG O 46
NAM CHIEN O Da D.C Arch 137 283 0.390 154 43 760 34 780 200 814
NUOC TRONG C RCC 68
SROK PHU
MIENG O Be 31 51 228
PLEIKRONG O Se San RCC 71 495 1,049 100 478
QUANG TRI O 75 163 64 220
SE SAN 4 O Se San RCC 74 850 1.42 893 360 1 450
SON LA O Da RCC 138 962 5.10 9 260 224 2 400 9 429
SONG BA HA O Ba ER 46 1 357 2.00 395
SONG BUNG 2 C Thu Bon CFRD 98 427 94.3 2.90 692 4 750 100 426
SONG BUNG 4 C Song Bung RCC 95 320 1 477 9 787 156 586
SONG CON 2 Con 50
SONG HINH 1 O Hinh E 42 940 2.10 357 41 15 772 7 000
SONG HINH 2 O Hinh E 19 1 466 1.30
SONG RAY O Ray 35
SONG TRANH 2 O Tranh RCC 96 521 1 100 9 609 190
Dam
State River Type HD LD (m) VD VR Area R L R Catchment
area
Spill.
Cap Pu W
Irrigated
Area
(m) (hm³) (hm³) (km²) (km) (km²) (m³/s) (MW) (GWh) (ha)
Comments
TA TRACH O Huong ER 56 1 187 646 717 20 80 34 782
TAN GIANG O 38
THAC BA O Chay ER 48 657 2 490 235 60 6 430 3 650 120 400
THAC MO O Be ER 50 460 1 733 1 360 109 10 2 200 3 725 150 610 42
UPPER KON TUM C ER 68 279 145.52 220 1 094
TRI AN O Dong Nai ER 40 420 2 765 323. 4 43 15 400 18 450 400 1 760 2 980
TRUNG SƠN C Ma RCC 88 520 348.5 13.13 13 175 260 1 055
TUYEN QUANG O Lo CFRD 92 718 2 245 81.49 14 972 12 735 342 1 329
VINH SON A O Dakphan E 35 410 1 000 34 2. 80 5 97 1 036 66 230
VINH SON B O Daksegnan E 37 300 700 97 9.90 10 117 319
YALY O Se San ER 71 1 142 8 605 1 037 64.50 40 11 450 17 400 720 3 650
TOTAL FOR
HYDROPOWER
12 120
MW
47 294
GWh
The main purpose of large dams and reservoirs is hydropower but very often they are multipurpose dams (flood control, irrigation, water supply).
Most of large structures are embankment (E, ER, CFRD) or RCC dams.
Dam
State River Type HD LD (m) VD VR Area R L R Catchment
area
Spill.
Cap Pu W
Irrigated
Area
(m) (hm³) (hm³) (km²) (km) (km²) (m³/s) (MW) (GWh) (ha)
5. Existing hydropower infrastructures
More than 30 power plants with a capacity > 50 MW.
HPP Son La has the largest capacity 2400 MW (with 6 units of 400 MW).
More than 350 small hydropower schemes (Independent Producers) with capacity varying from 5 to 30 MW.
Pumped Storage Plants
No pumped storage plants (PSP) have been built or commissioned to date. Between 2019
and 2030 five following PSP are planned to commission, totaling 5,700 MW and taking 3.9
percent of the installed capacity of the whole country: (1) Bac Ai 1: 4 x 300 MW, (2) Dong
Phu Yen: 4 x 300 M, (3) Don Duong: 4 x 300 MW, (4) Ninh Son: 4 x 300 MW, and (5) Mien
Bac: 3 x 300 MW
6. Flood Control
For these 8 reservoirs, the flood control is the priority and storage volume
may constitute a large part of the total capacity of the reservoir during the wet
season.
In the central part of Vietnam, there are often several floods every year
(typhoons) during the wet season.
Reservoirs of any types have the storage between Full Supply Level (FSL) and Maximum
Flood level (MFL) for flood control. Exceptions are eight large reservoirs, which are imposed
by law to allocate bigger storage between a level lower than FSL and MFL for flood control.
These eight reservoirs are indicated in the table below.
Reservoir River Flood control storage (hm3)
Thac Ba Chay (Lo River branch) 450
Tuyen Quang Lo River 1000
Hoa Binh and Son La Da River 7000
Cua Dat Chu River 300
Ta Trach Huong River 556
Dinh Binh Kon River 221
Nuoc Trong Nuoc Trong River ?
7. Main challenges
High increase of electricity consumption Population growth, urbanization and increased capita electricity consumption
will have a direct and considerable impact on future demand for electricity : this per capita consumption will increase from 1 774 kWh in 2015 to 3 703 kWh in 2025.
The necessary development of dams and reservoirs in Vietnam
- Vietnam is a country with large floods in the wet season and often severe droughts in the dry season (this trend may be worse in the future with the climate change),
- Vietnam has large demand for construction and exploitation of water resources by reservoirs,
- domestic water supply for urban areas is presently a critical issue,
- industrial water supply is increasing,
- exploitation of ground water is limited.
but the new projects encounter more and more obstacles.
Main obstacles for construction of new dams and power plants
- Financing issues: The rate of construction was slowed down these
last years since the lower growth of the electricity demand and the reduction of
the local bank loans with the economic crisis.
- Low profitability of irrigation dams: the fees paid by the farmers are in
general less than 50% of the real cost of the water provided by the irrigation
system.
- Resettlement issues: new reservoirs are generally located in areas
inhabited by Ethnic Minorities difficult to be displaced and with higher costs
(agreement of the National Assembly is required if more than 20 000 habitants
are concerned).
- Multi-usage of water: Problem of the sharing of the available quantity
of water for hydropower, irrigation and water supply in the dry season, the
different demands being the highest at the same time.
- Sedimentation: With the rapid reduction of several reservoirs volumes
for irrigation and water supply.
Low cost solutions, such as fuse plugs and PKW - to increase the FSL of these
reservoirs - were tested with success in central Vietnam.
- Environmental issues and sustainable development: Diminution of
cultivated lands as many reservoirs will be located in narrow valleys, with a
growing population, the priority being given to the food security.
Existence, and even extension, of natural protected areas claimed by the public
which delay or prevent the implementation of some new dams.
- Impact of the climate change on the designs of dams and sea
protection dykes (Vietnam will be one of the most affected countries by the
climate change).
Taking into account this phenomenon (larger floods, raising of the sea water
level) in the design of these structures is consequently necessary.
Issues due to the insufficient safety of many small dams
- Insufficient monitoring and maintainance of small dams (H < 15m) : in
particular for large reservoirs closed by long dykes which play an important role
for irrigation and water supply.
- Anarchic development of small hydropower schemes by private
Independent Producers with sometimes poor design, construction, operation of
the structures (dams and gates) and detrimental impact on environment. This
development is now severely criticized by the public and media and several of
these foreseen projects have been recently cancelled by the government.
Particular issues
- Development of the Mekong delta and numerous issues raised by the
existing or foreseen large hydropower schemes on the Mekong river upstream
Vietnam.
New technical innovations, to mitigate the drawbacks of these schemes, are
then required.
Thank you for your attention
