Prospect of Wave Energy in Malaysia - IEEE Xplore

2014 IEEE 8th International Power Engineering and Optimization Conference (PEOCO2014), Langkawi, The Jewel of Kedah, Malaysia. 24-25 March 2014

Prospect of Wave Energy in Malaysia Nahidul Hoque Samrat#1, Norhafizan Bin Ahmad#2, I.A. Choudhury#3 # Department of Mechanical Engineering, University Of Malaya Kuala Lumpur, Malaysia. 1 [email protected], [email protected], 3 [email protected]

Zahari Taha Faculty of Manufacturing Engineering University Malaysia Pahang Kuala Lumpur, Malaysia. [email protected]

funding for R&D renewable energy projects in various universities and institutes in Malaysia.

Abstract—In developing country like Malaysia, the demand for electricity is expected to rise with increasing urbanization and rapid industrialization. Currently energy production is mainly dependent on fossil fuel but in the near future fossil fuels will not be sustainable because of the depletion of existing reserves and their impact on the environment. Wave energy is an environmentally friendly and fastest growing renewable energy source for a sustainable electrical power generation of the future. Unlike others renewable energy resources, wave energy can produce electric power all over the year. As Malaysia has a total coastline of 4,675 kilometers so there is a great potential for utilization of wave energy in Malaysia especially along the coast and the islands. This paper presents a feasibility study of wave energy at different locations in Malaysia including the estimation of the total power available from the seas surroundings Malaysia. Furthermore, the analysis of investment, operation and maintenance cost for a wave farm is also presented.

This paper aims to estimate the wave energy potential, which is easily available around the Malaysia. Among all the renewable energy sources, solar and hydropower energy are the most popular in this country. But Malaysia is vastly surrounded by water and it has the 29th longest coastline in the world. It has a total coastline of 4,675 kilometers [4], so Malaysia has a massive potential of wave energy that may be a vital source of electrical energy generation. Sea wave is a simple natural phenomenon. Solar energy creates wind which then blows over the ocean and converts wind energy to wave energy. Once it is converted, this wave energy can travel thousands of miles with little energy loss. Although many wave energy conversion techniques have been patented and new patents are granted each month, there are only nine basic techniques on which these conversations are based. The nine basic techniques are heaving and pitching bodies, cavity resonators or oscillating water column, pressure devices, surging wave energy converters particle motion converters, Salter’s duck, Cockerell’s rafts, Russell’s rectifier and wave focusing techniques [5-6]. Among the various wave energy converters, the oscillating water column (OWC) is generally considered one of the most promising wave energy conversion devices. The coastal settings afford huge possibilities for wave power generation in Malaysia. Using OWC technology, energy can be obtained economically from Malaysian sea at a good average wave height and wave period.

Index Terms—Wave Energy, Coastline, Wave Height, Wave Period, Oscillating Water Column (OWC), Wave Power, Cost.

I. INTRODUCTION In 2010, the total electrical energy demand in Malaysia was 20,087 MW and the total installed capacity was 25,258 MW including all renewable energy sources. It has been predicted that Malaysian electrical energy consumption will double by 2020. The growth rate of electricity demand in Malaysia per annum is now at 3.2% [1]. Malaysia mainly uses fossil fuels, natural gas and coal for electricity generation. Both fossil fuel and burning coal are the principal agents responsible for air pollution, polluted soil, water shortages, widespread human illness and ecosystem degradation. The main problems caused by massive consumption of fossil fuel are global warming meaning emission of CO2. It is projected that by 2020, Malaysia will release 285.73 million tons of CO2 which is an increase of 68.86% compared to the amount of CO2 emitted in the year 2000. In Malaysia, electricity generation alone contributes 43.40% of the total CO2, which is the largest among all sectors [2-3]. Malaysia signed the previous Kyoto protocol on reduction of CO2 emission to the atmosphere. For this reason the Malaysian government is very concern about environmental issue and the government wants overall improvement of the CO2 emission. In the electrical sector, the Malaysian government is looking towards renewable energy sources. The government has initiated private farms and

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II. WAVE THEORY As derived by McCormick [7], within the sea waves there are two components of energy one of which is the potential energy and another one is the kinetic energy. Potential energy is related with the height of the wave while the kinetic energy is related with the rate of the water particles within the wave. Oceanic waves can be mathematically approximated by a sine wave, and therefore can be exhibited by a smooth, regular oscillation. The total energy for regular (sinusoidal) waves is obtained from:

E = E p + EK =

127

ρgH 2 λ 8

..........(1)


where, g is the acceleration due to gravity (9.8 m/s2), ρ is the mass density of water (1000 Kg/m3 for fresh water or 1030 Kg/m3for salt water), Ȝ is the wave length and H is the wave height (m). The total energy in deep water of a wave can be described by the linear theory [7] and is equally composed of potential energy E p and kinetic energy E K where:

ρgH 2 λ 16

..........(2)

The potential energy is a progressive wave of height H, whereas the kinetic energy is dependent on the motion of the particles. For a variable sea state, the transfer of wave energy from point to point in the direction of wave travel is characterized by the energy flux or more commonly, wave power given by:

P= where

ρgH 2 C g 8

Wave data of Kota Kinabalu and Mabul Island for the month of February and that of Pulau Mentagor for the month of December are not included in the analysis as the data was unavailable from MMDL. The data is analyzed by the ‘hindcast’ technique [8] and by using eq. (4). The mean output wave power from these five sites are estimated and presented in graphical forms.

..........(3)

C g is the group velocity and is represented by:

Cg =

C 2kh {1 + } = nC..........(4) 2 sinh(2kh)

where C is the phase velocity. In deep water C g = shallow water

A. Sarawak: Fig. 1 show the average wave height and wave period of Sarawak for one year. At this site, the maximum average wave height measured in the month of January was 1.56 m and the corresponding wave period was 4.76 s. On the other hand the minimum average wave height measured in the month of September was 0.59 m and the corresponding wave period was 3.95 s. The monthly mean power output is shown in Fig. 2. The average power output from this site is 5 KW/m.

C and in 2

Cg = C .

Now the output power for deep water is given from equation (3) such that:

ρgH 2 C b

[for deep water C =

16 2 ρg H 2T P= ..........(5) 32π

gT ] 2π

Wave Data of Sarawak 4

8 Monthly Average Wave Height (m) Monthly Average Wave period (s)

T is the period of wave (s). From above equation it is clear that square of the wave height is directly proportional to the wave period because other parameters of the equation are constant.

3

6 5

2

III. WAVE DATA ANALYSIS IN MALAYSIAN PERSPECTIVE o

7

M o n t h ly A v e ra g e W a v e H e ig h t (m )

P=

o

Malaysia is situated between 1 and 7 in the North latitude o o and 100 and 120 in the East longitude. The total land area is about 329,847 square kilometers and total coastline is 4,675 kilometers. Geographically, Malaysia can be divided into West Malaysia and East Malaysia. West Malaysia consists of Peninsular Malaysia which has coastline of 2,068 kilometers, while East Malaysia has 2,607 kilometers of coastline [4]. Malaysia has two types of monsoon, namely Northeast monsoon and Southwest monsoon. When the wind blows from central Asia to South China Sea through Malaysia and move on to Australia between the months of November to March, the northeast monsoon occurs. In the meantime, when the wind blows from Australia across the Sumatra Island and move to the Strait of Malacca between June to September, the

4 3

1

2

M o n t h ly A v e r a g e W a v e p e r io d ( s )

E p = EK =

Southwest monsoon occurs. Wave condition in Malaysia is influenced by the southwest monsoon and the northeast monsoon wind. Mainly during the period of northeast monsoon season beginning from November to March, wave power could be a significant alternative source of energy in Malaysia. The peak average wave height and wave period occurs from October to March. Six locations were selected for this investigation. These locations are Sarawak, Kota Kinabalu, Mabul Island, Pulau Mentagor Island and Perhentian Island. In this section the wave height, wave period and wave power are shown for different months of a year. The data is obtained by Malaysian Meteorological Department Labuan (MMDL) from 2005 to 2012. MMDL collected this data by using Acoustic Doppler Current Profiler (ADCP) equipment and Voluntary Observation Ship (VOS) Scheme.

1 0

0

Jan

Feb

Mar

Apr

May

Jun July Months

Aug

Sep

Oct

Nov

0 Dec

Figure 1: Wave Height/ Wave period data of a year for Sarawak.

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Wave Power of Sarawak

Wave power of Kota Kinabalu

12

16

14

M onthly A v erage W av e P ow er (K W /m )

M onthly A verage W av e P ower (K W /m )

10

8

6

4

2

12

10

8

6

4

2 0

Jan

Feb

Mar

Apr

May

Jun July Months

Aug

Sep

Oct

Nov

Dec

0

Jan

Mar

Apr

May

Figure 2: Mean wave power output of a year for Sarawak.

Jun

July Months

Aug

Sep

Oct

Nov

Dec

Figure 4: Mean wave power output of a year for Kota Kinabalu.

B. Kota Kinabalu: Fig. 3 shows the yearly average wave height and period data of Kota Kinabalu. At this site, the maximum average wave height measured in the month of January was 1.66 m and the corresponding wave period was 5.75 s. On the other hand, the minimum average wave height measured in the month of April was 0.43 m and the corresponding wave period was 8.91 s. The monthly mean output power for this site is shown in Fig. 4. The average power output from this site is 6.5 KW/m.

C. Mabul Island: Fig. 5 shows the annual average wave height and period data of Mabul Island. At this site, the maximum average wave height measured in the month of November was 1.66 m and the corresponding wave period was 8.6 s. On other hand the minimum average wave height measured in the month of May was 0.53 m and the corresponding wave period was 5.89 s. The monthly mean output power for this site is shown in Fig. 6. The average power output from this site is 7.91 KW/m.

Wave Data of Kota Kinabalu 4 13

Wave Data of Mabul Island 4

10 9 8

2

7 6 5 4

1

3 1 0

Jan

Mar

Apr

May

Jun July Months

Aug

Sep

Oct

Nov

9 8

3 7 6

2

5 4 3

1

2 0

10

Monthly Average Wave period (s) Monthly Average Wave Height (m)


11

3

M o n t h ly A v e ra g e W a v e p e rio d (s )


12

2 1

0 Dec 0

Figure 3: Wave Height/ Wave period data of a year for Kota Kinabalu.

0

Jan

Mar

Apr

May

Jun July Months

Aug

Sep

Oct

Nov

Figure 5: Wave Height/ Wave period data of a year for Mabul Island.

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0 Dec

M o n t h ly A v e r a g e W a v e p e r io d ( s )

Monthly Average Wave Height (m) Monthly Average Wave period (s)


Wave Power of Mabul Island 25

Wave Power of Pulau Mentagor Island 14

12

M o nthly A v erage W av e P ow er (K W /m )

M o n th ly A v e ra g e W a v e P o w e r (K W / m )

20

15

10

5

10

8

6

4

2

0

0

Jan

Mar

Apr

May

Jun

July Months

Aug

Sep

Oct

Nov

Dec

Jan

Feb

Mar

Apr

May

Jun Months

July

Aug

Sep

Oct

Nov

Figure 8: Mean wave power output of a year for Pulau Mentagor Island. Figure 6: Mean wave power output of a year for Mabul Island.

E. Perhentian Island: Fig. 9 shows the annual average wave height and period data of Perhentian Island. At this site, the maximum average wave height measured in the month of November was 2.1 m and the corresponding wave period measured in the month of December was 6.1 s. On other hand, the minimum average wave height measured in the month of February was 0.9 m and the corresponding wave period in the month of July was 4.64 s. The monthly mean output power for this site is shown in Fig. 10. The average power output from this site is 15.9 KW/m.

D. Pulau Mentagor Island: Fig. 7 shows the annual average wave height and period data of Pulau Mentagor Island. At this site, the maximum average wave height measured in the month of September was 1.15 m and the corresponding wave period was 5.89 s. On the other hand, the minimum average wave height has been measured in the month of May was 0.7 m and the corresponding wave period was 6 s. The monthly mean output power for this site is shown in Fig. 8. The average power output from this site is 7.00 KW/m.

Wave Data of Perhentian Island 4

Wave Data of Pulau Mentagor Island

8 Monthly Average Wave Height (m)

10 Monthly Average Wave Height (m) Monthly Average Wave period (s)

Monthly Average Wave Period (s)

7 6

2

5 4 3

1

2


8

3


M o n t h ly A v e r a g e W a v e H e ig h t ( m )

9 3

6 5

2

4 3

1

2 1

1 0

0

Jan

Feb

Mar

Apr

May Jun Months

July

Aug

Sep

Oct

7

0

0 Nov

Figure 7: Wave Height/ Wave period data of a year for Pulau Mentagor Island.

0

Jan Feb Mar Apr May Jun Jul Months

0 Aug Sep Oct Nov Dec

Figure 9: Wave Height/ Wave period data of a year for Perhentian Island.

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4


V. COST ANALYSIS

Wave Power of Perhentian Island 40

Cost estimates of energy produced by wave energy conversation are dependent on many physical and economic factors. These costs will vary region by region and depend on wave energy topology. The followings are enumeration of a few cost factors related with a wave farm [10-11]:

Monthly Average Wave Power (KW/m)

35 30 25

a) b) c) d) e) f) g)

20 15 10 5 0

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

Sitting and Permitting. Components: initial and ongoing costs. Installation. Taxes. Operation and Maintenance. Project lifetime. Average annual energy production.

The first four factors are included into the initial investment cost. So there are two main components: initial investment cost (IC) and operation & maintenance cost (OMC) which are needed for cost calculation.

Figure 10: Mean wave power output of a year for Perhentian Island.

Based on the analysis of this data, it can be concluded that the available average annual wave power in Malaysian sea is 8.5 KW/m with the highest annual wave power potential in Perhentian Island estimated to be 15.9 KW/m. The available wave power changes with the season. The lowest wave power occurs during the months in between the two monsoon seasons and the highest wave power occurs during the northeast monsoon season.

It is from the previous analysis that a 250 KW unit is suitable for Malaysian sea condition. The initial investment cost for a grid connected residential system of each unit of 250 KW is 1.3 million dollar and operation & maintenance cost is about 3000$/year. The total cost will be reduced by 30% if we install 100 or more units. So only using four square kilometer, a cost effective wave farm can be developed. The total cost calculation for generation of wave power in Malaysia is calculated and shown below [9-11]:

IV. WAVE POWER CALCULATION From the above wave data analysis, the average wave power of 8.5 KW/m available in the Malaysian sea is slightly lower for wave power generation. So it is a big challenge for wave energy conversion in Malaysia. Among the various wave energy converters, the OWC is generally considered one of the most promising wave energy conversion devices. OWC system has been successfully constructed and tested at a number of sites [5-6]. Moreover, OWC wave energy converter can run in slightly lower wave conditions easily. So, a 250KW OWC unit is suitable for wave power generation based on the Malaysian sea wave condition [9]. Each 30 m2 OWC device contains two 250 KW generators, so two generators will produce 500 KW. As the efficiency of OWC system is 48% [9], the total output power from each 30 m2 OWC device is 0.48 × 500 = 240 KW. If the total annual operation of each unit is 720 hours, the total annual output from each OWC device for Malaysia is 240 × 720 = 1728 MWh. Hence 30 units in one km2 will produce 30 × 240 = 7.2 MW. As Malaysia has about 4,675 km coastline, it has a total costal area of 4675 × 10 = 46750 km2. So the total generation of wave energy will be about 46750 × 7.2 = 336600 MW. If 7% of the coastal area is harvested, then approximately 23562 MW of energy can be extracted, which is equivalent to the present energy needs of Malaysia.

Initial investment cost for 100 units as well as whole wave farm is equal to 1.3 × 100=130 million dollar. Operation & maintenance cost per year of 100 units is equal to 3000 × 100=300000$ The average life time of an OWC device is more than 20 years. Let us assume a 20 years estimate of useful life. So the annual cost of the whole wave farm for this si te = Annual cost + Annual operating & maintenance cost) ( Expected lifetime

=(

130,000,000 + 3,00,000) 20

= 68,00,000 $

In this site, if 100 units of OWC are installed, the total cost is reduced by 30%. Thus the total cost for this site is (68, 00,000 × 0.3) =2,040,000$. It has been calculated in power calculation section that annual energy output from each unit is 172.8 MWh. So the annual output from 100 units is (100 × 172.8) =17280 MWh. The

131

cost

per

KWh

=

Annual

Annual cost energy output


∴ T he cost per K W h =

REFERENCES

2040000 = 0 .1 1 U S D /K W h 17280000.

Total cost per KWh for wave power generation in Malaysia is 0.11USD/KWh or 0.33 RM/KWh and it seems that the cost per KWh of wave power generation is less than 1,071 MW Prai gas fired power plant, which will expected to commence operation by March 1, 2016 [12].

[1] S. Mekhilefa, A. Safari, W.E.S. Mustaffa, R. Saidur, R. Omar, M.A.A. Younis,"Solar energy in Malaysia: Current state and prospects", University of Malaya, 50603 Kuala Lumpur, Malaysia. [2] [Online: March 2013] "CO2 Emissions by country", http://www.nationmaster.com/graph/env_co2_emi-environmentco2-emissions. [3] Nor Sharliza Mohd Safaai,Zainura Zainon Noor, Haslenda Hashim, Zaini Ujang, Juhaizah Talib, "Projection of CO2 Emissions in Malaysia", Published online 00 Month 2010 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ep.10512. [4] [Online: March 2013] "Geography of Malaysia", http://en.wikipedia.org/wiki/Geography_of_Malaysia. [5] Annette Muetze, Jennifer Vining, “Ocean Wave Energy Conversion”,ECE699:Advanced independent study report, University of Wisconsin-Madison, December-2005. [6] Ruo-Shan Tseng, Rui-Hsiang Wu, Chai-Cheng Huang (2000), “Model Study of a shoreline wave power system”, Ocean Engineering, 27, pp.801-8021. [7] D.G. Dorrell and W. Fillet, “Investigation of a small scale segmented oscillating water column utilizing savonius rotor turbine”, International Conference on Energy and Environment 2006 (ICEE 2006). [8] Robert G. Quayle and MichaeJl. Changery, "Estimates of Coastal Deepwater Wave Energy Potential for the World", National Climatic Center, Asheville, NC 28801. [9] Arup Energy, "Oscillating Water Column Wave Energy Converter Evaluation Report", by Carbon Trust 2005. [10] Jennifer G. Vining, Annette Muetze, "Economic Factors and Incentives for Ocean Wave Energy Conversion", IEEE Transactions on Industry Applications, Vol. 45, No. 2, March/April. [11] Lihui Guo, "Applicability and potential of wave power in China", Department of Technology and Built Environment, University of Gavle, June 2010. [12] [Online: March 2013] "Two IPPs get 10-year extension; TNB to build Prai plant", http://biz.thestar.com.my/news/story.asp?file=/2012/10/10/busin ess/12149089&sec=business.

VI. CONCLUSION Power is one of the most important factors for developing the socio-economic conditions of a country. In most of the islands in Malaysia, national grid will not available yet many years. That’s why economic and educational growth rate of these islands communities are very poor. But Malaysia has excellent wave energy resource, so wave energy technology will be one of the major reliable energy resources for these islands communities. There are several sites identified as economically viable for commercial scale generation because any site in the world are able to generate wave energy at competitive prices if it has an average wave power level equal or above 15KW/m and these sites are considered to have an exceptionally high energy resources than wind and solar. However, there are numerous other sites, which are not economically viable mainly due to the wave power level being less than 15KW/m. As the prospect of wave energy is promising, further research is needed for making these sites economically viable. As the renewable energy research in Malaysia is relatively new, the demand for making unviable sites in to viable ones require more in depth research.

ACKNOWLEDGMENT The authors would like to thank KeTTHA, Ministry of Energy, Green Technology and Water and University of Malaya for providing financial support under the research grant no:53-02-03-1102 “Active Control and Efficiency Optimization of Turbine Blades for Oscillating Water Column Device”.

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