Possibility of electricity from wind energy in Malaysia: Some rough calculations

Update (10 Apr. 2013): This article was used as a source of reference in the New Straits Times article “Getting wind of the situation” (pg. 7, Green Technology section, April 9, 2013) by Gregory Basil.

Is it possible to harness the wind energy on a large-scale basis to generate electricity in Malaysia? Malaysia’s mean annual wind speed is low at no more than 2 m/s. Nonetheless, the wind does not blow uniformly throughout Malaysia; wind speed varies according to region and month.

What’s the future for wind energy in Malaysia? (photo from pkukmweb.ukm.my/~jkas)

Malaysia experiences two main weather seasons: southwest monsoon (May/June to September) and northeast monsoon (November to March). Wind speeds during the southwest monsoon are often below 7 m/s, but during the northeast monsoon, wind speeds could reach up to 15 m/s particularly in the east coast of Peninsular Malaysia. Moreover, during April to September, the effects from typhoons striking neighbouring countries (such as Philippines) may cause strong winds (even exceeding 10 m/s) to Sabah and Sarawak.

So although Malaysia, as a whole, experiences low wind speeds, some areas in this country see strong winds during certain periods of the year.

I requested the wind speed data for 14 towns from all over Malaysia from the Malaysian Department of Meteorology. These data were from 1989 to 2008 (20 years), and in addition to them, I included the wind speed for Serdang, the town where my university main campus is located. For Serdang, the wind speed data were from 1985 to 2007 (23 years). All wind speeds were typically measured 2 meters above the ground.

From my analyses, Malaysia experiences stronger winds in the early and late parts of the year. On the whole, Malaysia’s mean annual wind speed is 1.8 m/s. However, towns in the east coast of Peninsular Malaysia such as Mersing, Kota Baharu, and Kuala Terengganu experience stronger winds. For these places, their mean monthly wind speed could exceed 3 m/s. East Malaysian towns, Kota Kinabalu and Labuan (with the exception of Kuching) also see stronger wind speeds than the national average.

Mean monthly wind speed for several towns in Malaysia, 1989-2008. Mean annual wind speed of a given town in brackets (1 of 2)

Mean monthly wind speed for several towns in Malaysia, 1989-2008. Mean annual wind speed of a given town in brackets (2 of 2)

Okay, let’s round up the mean wind speed of Malaysia to 2 m/s. This is the national average of wind speed at 2 m height above ground. Roughly, doubling the height increases wind speed by 10%. Since a typical wind turbine is 32 m above ground, this means the average wind speed at the height of 32 m above ground increases to nearly 3 m/s.

The energy per square meter area of a wind turbine is determined as:

0.5 x air density (kg per cubic meter) x wind speed x wind speed x wind speed

Note that wind speed (m/s) is cubed (multiplied by itself thrice). Using the aforementioned equation and taking air density as 1.3 kg per cubic meter and mean wind speed as 3 m/s give the energy per square meter area of a wind turbine as 17.55 W.

The diameter (d) of a typical wind turbine is 25 m, so the circular area of a wind turbine is:

3.142 x 0.25 x d x d = 491 square meter

Hence, the total power generated from a single windmill is:

17.55 W per square meter x 491 square meter = 8,617 W

However, the efficiency of windmills is not 100% but typically only about 50%. This means the actual total power generated from a single windmill (i.e., after correcting for inefficiency) is half of 8,617 W or 4,309 W.

Now let’s determine the power that could be generated from a square meter of land area occupied by windmills. Windmills cannot be placed too closely to each other. Doing so would cause one windmill to slow down the wind speed for another windmill. But placing windmills too far from each other wastes land area. Typically, windmills are placed no less than five times their turbine diameter without losing power. Hence, the power that could be generated by windmills per unit land area is

power per windmill (W) / land area per windmill (square meter)

or

4,309 W / [(5 x 25 m) x (5 x 25 m)] = 0.28 W per square meter land area

Recall that the diameter of a typical wind turbine is 25 m and two adjacent windmills are placed apart by five times their turbine diameter.

Windmills typically require a minimum wind speed of between 3 to 5 m/s to generate electricity. This means there would be periods of too low wind speeds for the windmills to generate electricity. Periods in a day with enough wind speed for the windmills to generate electricity is called “load factor” or “capacity factor”. So, what is the load factor for windmills in Malaysia on the whole?

In calm weather, the typical wind speed distribution in a day can be depicted as below.

Idealized daily wind speed distribution in Malaysia

Wind speed is higher during the day (from sunrise to sunset) than that during periods before sunrise and after sunset. Wind speed follows a sine curve during the day, and it remains constant for periods before sunrise and after sunset.  I am going to roughly estimate Malaysia’s load factor by assuming that maximum wind speed is twice the daily average wind speed and that the average wind speed during the day is also twice that during early morning and night.

Consequently, the period when wind speed exceeds 3 m/s, which is required for windmills to generate electricity, is calculated to be from 8:45 to 17:15 hours. This is a duration of 6.5 hours or a load factor of 27% where windmills are able to harness the wind for electricity generation.

Thus, the power that could be generated by windmills per unit land area is 27% of 0.28W, which is 0.0756 W per square meter land area or 1.8 Wh of electricity generated per square meter land area per day.

Malaysia’s demand in electricity by 2020 is expected to reach 124,677 GWh, so if wind power is to meet, say, 10% of this projected electricity use, the total land area of Malaysia needed for windmills is:

(124,677 x 1000 x 1000 x 1000 x 0.1) /( 1.8 x 365) = 18,977 square kilometer

This area is equivalent to 6% of the total land area of Malaysia, or equivalent to over 1.2 million windmills to be set up.

Currently, it cost about RM1 for every 1 W of electricity generated from wind energy in Malaysia. Thus, to meet 10% of Malaysia’s electricity demand in 2020 would cost approximately RM1.4 billion to setup the required number of windmills. These figures so far show it is plausible to harness the wind energy for electricity generation in Malaysia.

Although the minimum wind speed required for windmills is between 3 to 5 m/s, the minimum wind speed for commercial viability is instead 7 m/s. None of the 15 towns I analyzed had mean monthly wind speeds exceeding even 5 m/s.

According to Tenaga Nasional, in collaboration with Argentina’s renewable energy firm, Industrias Metalurgicas Pescarmona S A (Impsa), 500 to 2000 MW worth of electricity could be generated from wind energy in Malaysia (meeting between 3.5 to 14% of the expected demand in electricity by 2020). They further reported there are areas such as the Malaysian-Thailand border which see wind speeds up to 15 m/s.

It is interesting to note that wind energy suffers contrasting problems with solar energy. Technology for solar energy is prohibitively expensive for large scale use in Malaysia. In contrast, harnessing wind energy is much cheaper than that for solar energy to set up in this country. Malaysia enjoys plenty of sunshine (as much as 3 kWh per square meter) all year round, but Malaysia sees only low wind speeds and sees high winds only at certain times of the year.

Windmills in Perhentian Island (photo from razmahwata.wordpress.com)

I believe there is certainly an avenue for using wind energy in Malaysia, but wind energy can only be used in limited areas and in certain periods only (e.g., early and late in the year). Coastal areas, especially in east Peninsular Malaysia and East Malaysia, including small islands (such as Perhentian Island), could benefit from wind energy. But for the majority of Malaysia, the solution of large scale and uninterrupted renewable energies lies elsewhere.

References

  1. Sustainable Energy – Without the Hot Air” by David J.C. MacKay, UIT Cambridge Ltd., 2009.
  2. Harnessing the power of the wind” by Yvonne Chong, Malaysian Business, Oct. 16, 2009.
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Comments

  1. Hi Guys
    wind turbines on a large scale has to be located in the deep seas not inland.The report seem to suggest the Malaysian winds will not be able to generate electricity. Even in the USA,UK the wind farms are located in the deep seas where the winds are consistent. P Perhientian may be a failure, but there is no report on this.We have to see what went wrong. So it is best not to quote P.Perhentian. The winds off the sea coast along the SChina Seas are more than 5m/s . which is more that sufficient

  2. Very nice blog!

    I’m interested in the possibilities and developments of offshore wind in Malaysia. Would you know of someone whom I can contact about this?

    Kind regards

  3. can i know the average wind speed of Sabah? because i am going to design a solar vertical axis wind turbine in my fyp. thank you.

  4. what if we place wind turbines on 20-30 storeys hotels in certain resort in Msia? could wind energy be harness?

    • Interestingly, the blueprint for renewable energy and energy efficiency for Iskandar Malaysia (Blueprint) makes no mention on using wind as a source of renewable energy. The problem is always on the low wind speeds in Malaysia, making wind turbines in most places not practical.

  5. Hi Dr. Chris & fellow bloggers,

    Wind power in the tropics is a virtual no-no & I believe the experience of the wind-solar-diesel hybrid system in P. Perhenrtian is good example to show that we need to be more realistic in pursuing this form of RE.

    Cost figures shown in the calculations are not realistic: e.g. the capex for power generation from wind cannot be RM 1.0 per W. Even conventional OCGT costs about RM 2.5 per W. To the best of my knowledge the cost for wind power generation would be at least RM 5 to RM 10 per W for units of megawatt capacity. Adding to that the potential low capacity factor, even if adequate wind is available, & the high O&M costs will make it economically unjustified, perhaps even more costly than solar PV.

    I believe that we should concentrate on exisitng & viable RE from biomass, biogas, waste-to-energy & small/mini hydro power plants.

    Now why have I ignored solar PV? well even SEDA has admitted in its presentation at a “National Energy Security Conference 2012” on 28 Feb. 2012 that PV is not a suitable alternative to conventional power generation, whether for base load or for peak load; & that’s not merely because of the cost.

    You may want to see the web page below (YBM KeTTHA’s blog) for more “incisive (critical) comments on the subject.

    http://peterchin.my/?p=2701#comments

    Sorry if I sound like being a “wet-blanket”, but believe me, we should not get “carried away” with FiT payments for improbable RE options as these payments come from our (electricity users’) pockets.

    Lal

  6. Dear Dr Teh & fellow blog participants,

    Recently a wind turbine consultant asked about feasible locations in Malaysia for wind turbine power generation. I referred the consultant to http://eprints.usm.my/9180/1/Potential_of_Renewable_Wave_and_Offshore_Wind_Energy_Sources_in_Malaysia_(PPKMekanikal).pdf , but the consultant claimed that the data there is dated 2003 & wind patterns would have changed. Is this true? Do wind patterns change that much over 8 years?

    Comparing (1985-2000) data at the above URL with data on this blog (1989-2008), it seems there may be some truth in the consultant’s statement, e.g. mean wind speeds at the Terengganu coast area seem to have increased. Would you agree..?

    If this is true, then how much %error margin should we factor in to ROI calculations for windfarms to cater for changes in wind patterns over a windfarm’s lifespan..?

    • Unfortunately, the paper you gave did not mention exactly where the wind data from East Peninsular Malaysia were measured. Perhaps they got the average of several locations instead of one, as I have done. To get a clear trend of weather change, we need at least 20 years of data.

  7. Hi Mr teh, i’m Wong, one of the final year student from university malaya, and having my last year project with title of wind hybrid system. And i need some data for my thesis, can u tell me tat how could i get the Energy or power used data from perhentian Island, and also the wind speed.

    • I am not sure how one would obtain the power generated from the wind turbine at Pulau Perhentian. However, the wind speed data can be obtained from PJ’s Met. Dept for a fee, depending how much data you require. Your supervisor must help you on this.

  8. Hi Christopher, this is an interesting article about the suitability of wind power in Malaysia. While the ‘mill on Perhentian can benefit from the constant strong winds from the South China Sea, I’m just wondering about my rather stuffy home of PJ, which suffers from a serious lack of wind most of the time!

    Mr. Nizam’s turbine which can operate at low wind levels seems to be a great way for this environmentally-friendly energy source to take off in Malaysia. I’m just wondering where the prototype will be located, on a hill or top of some high-rise building?

    And who knows, in future, we can see some wind farms all over our country and similar to the ones I’ve seen near Ballarat and Geraldton (both in Australia), albeit at a smaller scale!

    • Thanks for your visit and comments. Yes, PJ has a low wind speed especially when with lots of obstacles to wind flow there. I think it is not worth getting a home wind turbine because of the low wind speeds and you would need a large turbine to generate sufficient electricity.

      What you can do is to look at your electric bills to determine the average amount of electricity you use per month and work out the size of the wind turbine you need to, say, fulfil 50% of that demand.

  9. Hello Nizam and Yatie,I am a manufacturer and have develop a VAWT and looking for ideas/product to improve my wind turbine.

    Your wind turbine that can operate at 2 m/s is interesting and I am thinking of combining air compressor to the turbine.

    The compressor works when the turbine is generating electricity then store air in gas cylinders when there is no wind the compressor powered from the energy in the batteries spin the turbine and it cuts off when the rpm of the turbine picks up.

    Please contact me so that we can make use/commercialise your both ideas.

    My hp number is 0122737348

  10. Hi Everyone,

    The key befre any wind energy solution to be implemented here is wind map. A wind map of of the whole Malaysia has already been developed in 2001. From the wind map we know that 65% of Malaysia’s area have a wind speed of between 2.5m/s to 5m/s, 65% of the time (roughly 14 to 16 hours of wind speed between 2.5m/s and 5m/s). This mean that Malaysia is under a Class 1 Wind area – either low wind speed or none at all. This also mean that only low wind speed wind turbine that produce up to 30kW of electricity can work productively.

    Obviously, any wind turbine designed by companies coming from Class 3 or 4 countries (medium to high wind speed) would not work and cost effectively here.

    We have the solution. Locally made and designed wind turbine by Malaysia’s own researcher. The turbine can produce up to 3.6kW of power. The start-up wind is at 2m/s and rated (full capacity) at 5m/s. Since 1998 several prototypes have been designed, the latest being developed in 2009. We are hoping to have this design to be installed up on a tower by this July.

    Our main concern is always securing/getting funding or loans from banks. We hope to commercialize and mass produce the turbine by year-end. When dealing with banks/funder, we are always in the “Chicken or Eqq” situation, whereby for us to secure any funding, we must show profits in our accounts. How can we show profit if it is not mass produced yet? Duh…Sigh.

  11. I do agree with Apai. Offshore application should be a consideration, well, balance of cost and benefit is an interesting part.

  12. wow…it is a good analysis towards the possibility in establish the wind power plant in Malaysia. Perhaps we can have a suitable wind turbine in the coming future.
    By the way, as you mentioned you had obtained the wind speed for 14 towns ranged 1989 to 2008. Can I have a copy of that?
    Thanks in advance.

    • Thanks for the compliment. The weather data I got is from the Malaysian Meteorological Dept (MMD) under the condition it is not used beyond the reason I had applied for it. Hence, I can’t distribute the data. Anyway, if you look at the charts, you could, with some effort, tease out the monthly averages for the 14 towns. Alternatively, you can go over to the MMD at Petaling Jaya Service counter and apply for the data.

  13. I’ve made similar studies into this and currently is still working on this topic. for present, it is possible to generate wind energy in Malaysia by using low wind speed wind turbines and vertical axis wind turbines (VAWT). I can send the report if you want to have a look on it 🙂

  14. interesting read.
    However i do think that the calculation for total energy from a windmill is missing one more step. As you rightly noted that turbines usually have a cut in speed of around 3-4 m/s, theres also the fact that rated power is usually only achievable at around 15-20 m/s. For example, a usual turbine in europe would be a vestas V90 3Mw (90m diam rotors), would only produce full power at 15m/s and only around 300 watts around 5 m/s…
    this is a huge factor when you take it into account.
    In the UK, power suppliers are paid extra on top of base energy costs (under what they call a renewable obligations certificate) for wind energy.

    I think that wind on a big scale is a definite no no in malaysia, however very possible in remote locations

    • Thanks for your feedback. I agree that electricity generation from windspeed in Malaysia is limited. Our best potential lies in bioenergy from oil palm and to some extent, solar energy.

  15. Although climate data has been recorded for a number of years and the facts and figures are out there I believe not enough emphases is being placed on development of renewable and sustainable energy resources locally available, specifically tailored for this region and in particular Malaysia. Almost all installations tried are using equipment and designs from foreign manufactures that have spent a large amount of resources to develop and perfect their products, and they more often than not are not suitable for this region due to its unique geographical location.

    Researchers here are not thinking outside of the box.

    Malaysia’s geographical location does pose some challenges to harnessing the natural resources available, but on the other hand does have benefits that many other locations geographical do not enjoy. A predictable and stable climate with limited natural disasters means long term development of the natural recourses available can be sustained.

    The only possible threat to any long term project would be Climate Change and as we all are lead to understand this is ongoing and not exactly predictable.

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