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Wave Energy Resource Assessment
for Southeast Asia
1 Energy Research Institute @ Nanyang Technological University (ERI@N)
Tropical Marine Science Institute, National University of Singapore
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PRESETATION OUTLINE
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Methodology
• Numerical Wind-Wave Modelling
• Model Inputs
• Model Computations
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Potential of Wave Energy in South East Asia
• Annual mean wave energy
• Seasonal variations of wave energy
• Wave energy in Singapore
Conclusions and Perspectives
METHODOLOGY
 Numerical Modelling:
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• Applying MIKE 21 SW (Spectral Wave)
• Simulating the growth, decay and transformation
of wind-generated waves and swells in offshore
and coastal areas
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 Domains:
1. Indo-Western Pacific (IWP) domain: to provide
boundary conditions for the smaller domain
2. South East Asia (SEA) domain:
(South China Sea, Malacca Strait and
Singapore Strait)
METHODOLOGY
 Wind data:
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 Bathymetry data:
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• Gridded wind data (at 10 m height) from National Centers for Environmental Prediction
(NCEP) with spatial resolution of 2.5°×2.5° and temporal resolution of 6 hours are applied in
the IWP model.
• Wind data computed using Weather Research and Forecasting (WRF) model for SEA model,
30km × 30km spatial resolution and 6-hour temporal resolution.
• ETOPO5 (for the Indian Ocean and part of
Western Pacific) and ETOPO1 (for SEA) from
National Geophysical Data Center (NGDC),
U.S.A.
• Scattered depth data from Electronic
Navigational Chart (for the Singapore Strait).
Interpolated bathymetry in Singapore Strait
METHODOLOGY
 Duration: 1-year period
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Model computations:
 Spectral discretization (logarithmic): 25 bins of frequencies, minimum frequency – 0.055 hz
and frequency factor – 1.1
 Directional discretization: 360° rose with 16 directional bins (22.5° in each bin)
 Bottom friction: Nikuradse roughness, kn = 0.02m
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 White capping: dissipation coefficient, cdis = 4.5, DELTA dis = 0.5
 Wind sea and swell parameters separated using a dynamic threshold frequency approach
where the maximum threshold was given as 0.3 hz
 Model outputs (for every 6 hour): integral wave parameters (wave height, wave period,
direction etc.) and wave energy spectra
ANNUAL WAVE ENERGY POTENTIAL IN S.E.A.
SWH
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Annual Mean Wave Energy is highest
in the western side of Sumatra island,
the Andaman Sea part offshore of
Myanmar, followed by the South China
Sea area between Vietnam and the
Philippines
Wave power per unit crest (assumption
for deep water waves):
Wave period
Annual Mean Wave Power
WAVE ENERGY POTENTIAL IN S.E.A. (MONSOONS)
Southwest monsoon (Jun-Sep)
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Northeast monsoon (Dec-Mar)
 Wave power of South China Sea is the highest during Northeast Monsoon (NEM), and significantly lower during
Southwest Monsoon (SWM). Maximum wave power is in the northern sea waters of Luzon island, Philippines.
 Wave power of the southwestern side of Java Island is the highest during SWM, due to high waves from the South
Indian Ocean.
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WAVE ENERGY POTENTIAL IN S.E.A.
(INTER-MONSOONS)
• Wave energy during inter-monsoon periods (April to May and October to November) are lower than monsoon
periods.
• The Indian Ocean and Andaman Sea parts show greater wave power than other parts in the two intermonsoon periods
WAVE ENERGY POTENTIAL IN SINGAPORE
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 The area producing greatest wave energy in
Singapore Strait is in the south east of the island
because of higher energy swells and wind waves
propagating from South China Sea, (larger depth
and fetch).
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 The total annual wave energy within the buffer
area covering 2 km from the coastline of
Singapore is estimated to be approximately
47.2 GWh.
WAVE ENERGY POTENTIAL IN SINGAPORE
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 Most energetic waves are corresponding to
north-east monsoon due to swell-waves
propagating from the southern SCS
(predominantly easterlies) and wind-seas in
the Singapore Strait (north-easterlies).
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 Wave energy during south west monsoon is
particularly low due to limited fetch and
shallow depth.
 Wave energy in the other seasons is
insignificant because of weakening synoptic
wind. Major inputs to the wave energy are
produced by local wind systems such as
sea breeze.
Ongoing works: Wave Measurements
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Wave Rider
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Different types of sensors have been deployed in Singapore sea waters recently by ERI@N for validation purpose and other site feasibility studies : Wave Staff
ADCP Conclusions & Perspectives
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 Modelling result presents the maps of annual and seasonal mean wave energy of the SEA region.
 Wave energy is highest in the western side of Sumatra island, the Andaman sea part offshore of
Myanmar, followed by the south china sea area between Vietnam and the Philippines.
 Within the Singapore Strait, wave energy is found to be strong in the south east, and showing the
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greatest magnitude during northeast monsoon.
 The available wave power is not of high level compared to northern Europe or Australia, which is
understandable, given the wave conditions of Singapore waters. Nevertheless, Singapore should not
put aside any tappable source of renewable energy. The high predictability and sustainability of ocean
waves can contribute to resolve the growing need of electricity in the next decades.
REFERENCES
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 Cahill, b. G. And Lewis, T. (2013). Wave energy resource characterization of the Atlantic
marine energy test site. International Journal of Marine Energy. Vol. (1), pp. 3-15.
 DHI (2012). MIKE 21 spectral waves FM user manual, DHI Water & Environment. 122 pp.
 http://erian.ntu.edu.sg/Pages/Home.aspx
 Young, I.R. (1999). Wind generated ocean waves. In Elsevier Ocean Engineering Book
Series, volume 2. Eds. R. Bhattacharyya and M.E. McCormick, Elsevier.
20
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Wave Energy Resource Assessment
for Southeast Asia
1 Energy Research Institute @ Nanyang Technological University (ERI@N)
Tropical Marine Science Institute, National University of Singapore
SE
E
2