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  • ID CKM.BPK.EE/PK/09/01

    TARIKH 28.12.2009

    KAJIAN DAN PEMBANGUNAN

    CKM.BPK.EE/PK/09/01

    FEASIBILITY STUDY OF DIRECT FIRED AND SOLAR THERMAL ABSORPTION

    CHILLER

    Bahagian Pembangunan Kepakaran Cawangan Kejuruteraan Mekanikal

    Ibu Pejabat JKR Malaysia

    UN

    IT K

    EC

    EK

    AP

    AN

    TE

    NA

    GA

    DA

    N T

    EN

    AG

    A D

    IPE

    RB

    AH

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    UI

  • 1 Table of content

    2 INTRODUCTION ................................................................................................................................... 3

    2.1 Objectives of Study ................................................................................................................................. 3 2.2 The Solar Absorption Chiller to be supplied ................................................................................ 3 2.3. The Renewable Energy Technology to be investigated to meet this demand ................ 4 2.4 Design approach and evaluation ...................................................................................................... 4

    3 CURRENT SITUATION ON THE CASE STUDY BUILDING ......................................................... 5

    3.1 Air Conditioning Specification for the Building .......................................................................... 5 3.2 Data collected from case studied building. ................................................................................... 6 3.3 Electricity cost analysis ........................................................................................................................ 7

    4 BASIC PRINCIPLE OF SOLAR THERMAL ABSORPTION CHILLER ......................................... 9

    5 COMPARATIVE ANALYSIS ON ABSORPTION LIQUID ........................................................... 11

    6 CHARACTERISTIC OF THE ABSORPTION CHILLER TO BE EMPLOYED .......................... 13

    6.1 Types of solar Collectors ................................................................................................................... 13 6.2 Advantage and Disadvantages of Evacuated tubes: ............................................................... 14 6.3 Governing the temperature of Solar Collector for the Application .................................. 16 6.3 Solar insolation for Kuala Lumpur for studied evacuated tubes. ...................................... 19

    7 EVALUATION OF OPTIONS ............................................................................................................ 22

    8 CONCLUSIONS AND RECOMMENDATIONS ............................................................................... 24

    9 REFERENCES....................................................................................................................................... 25

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    List of Figure

    Figure 2: Cooling load profile of studied building ................................................................................ 6 Figure 3: Electricity cost for year 2007 .................................................................................................... 7 Figure 4: Electricity cost for year 2008 .................................................................................................... 8 Figure 5: Electricity cost for year 2009 .................................................................................................... 8 Figure 6: Basic principle of absorption chiller,

    http://www.raee.org/climatisationsolaire/doc/technical_overview_of_active_techniques.pdf ....................................................................................................................................................... 9

    Figure 7: The design of solar thermal absorption cooling ............................................................ 10 Figure 8, The various type of absorption chiller. ............................................................................... 12 Figure 9: Collector Efficiency of Various Liquid Collectors. .......................................................... 14 Figure 10, cross section through a direct flow vacuum tube ..................................................... 15 Figure 11: Monthly variation of solar radiation, Assilzadeh et al, (2005), Journal of

    Renewable Energy ............................................................................................................................... 18 Figure 12: Solar Fraction and Cooling load of the studied building. .......................................... 21 Figure 13: Purposed load profile between solar and direct fired absorption chiller. ......... 22

    List of Tables

    Table 1: Specification of absorption chiller ......................................................................................... 13 Table 2: Specification of Solar Collector ............................................................................................... 21 Table 3: System comparison for Klinik Kesihatan. ........................................................................... 23

    List of Appendixes

    Appendix 1: Natural gas tariff in Malaysia ........................................................................................... 26 Appendix 2 : Electricity tariff (Medium commercial ) ................................................................. 26 Appendix 3: Mean emission for electricity in Malaysia . Source: Energy Centre Malaysia,

    http://www.ptm.gov.my ................................................................................................................... 27

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    2 INTRODUCTION

    High energy consumption in Government hospital building in Malaysia is crucial and

    would highly impacted the yearly operating cost of the building. This problem should

    have been encompassing in the early stage of infrastructure. Therefore, during the

    preliminary design stage the builders, architect and engineer should included a

    renewable energy and efficient design features in every building that they planning to

    build.

    From the energy audits for Governments hospitals building in Klang Valley carried out

    by Green Technology Centre has annotate that nearly 60% of total energy consumption

    were contributed by the air-conditioning system (PTM, 2009) . Hence this shown air-

    conditioning represents the biggest single power consumer in public and commercial

    sectors.

    This study is involving an example of Government hospital building which will be

    adapted sustainable design features to reduce energy consumption and reduce green

    house gas emission in the building. The renewable energy technologies chosen for this

    particular study are solar thermal absorption chiller and gas fired absorption chiller.

    2.1 Objectives of Study

    The aims of this project are to:

    Introduce new renewable energy technology opportunities for Hospital buildings

    in Malaysia

    reduce energy consumption and operation cost of air-conditioning systems

    Investigate the economic feasibility on adapting solar thermal absorption chiller

    (STAC) in hospital building.

    2.2 The Solar Absorption Chiller to be supplied

    The Solar Thermal Absorption chiller will be employed in the Government hospital

    building. The average solar radiation solar radiation in Malaysia is approximately around

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    NORHAYATI_EERE_CKM 4

    700 KJhr/m2 (Assilzadeh et al, 2005), hence we should take this opportunity to harness

    the availability of power from sun to generate cooling equipment in the building as an

    alternative energy sources rather than depending on conventional fossil fuel energy

    generation.

    The scope of this project is to compare the advantage and disadvantage of using Solar

    Thermal Absorption Chillers and compared with the conventional electricity powered

    chillers systems. There are a few key questions to be answer

    Is there sufficient solar radiation to supply the Solar Thermal Absorption Chillers?

    availability of day lighting in the skies,

    Size of the solar collector

    Natural gas availability in propose area

    Type of solar collector

    In the report, a comparative analysis will be conducted into the various types of solar

    collector so that the most effective solar collector would be installed with the absorption

    chillers. Analysis on pros and cons of various type of absorbent liquid will also be

    included in the report.

    2.3. The Renewable Energy Technology to be investigated to meet this demand

    Find the average availability of solar radiation in the area proposed

    Identify and define the characteristic of the absorption chiller is to be propose

    Calculate the size of solar collector base on the solar radiation availability

    Briefly choose the solar collector type and the refrigeration type for the

    system

    Briefly compare the electricity consumed by conventional chiller and

    compared with Solar Thermal absorption chiller

    2.4 Design approach and evaluation

    The design approach for this project would be the technical and economic evaluation

    which would include basic preliminary design of solar thermal absorption chiller with

    suitable collector type for an efficient operation compared to conventional air-

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    conditioning systems such as air-cooled chiller or the absorption chiller power by gas

    engine.

    3 CURRENT SITUATION ON THE CASE STUDY BUILDING

    The solar thermal absorption cooling will be adapted in the Small hospital buildings

    which will be tenure by the Health Department of Malaysia. The proposed building is a

    two floors building with a pitch roof with the gross air-conditioning area of 2828 m2. The

    normal operation for the studied building is 8 hours starts from 8.00am to 5.00 pm,

    however, all the equipment such as air-conditioning and lighting starts from 8.15am to

    5.30pm daily.

    3.1 Air Conditioning Specification for the Building

    The design of this building is assume to use the data based on American Society of

    Heating, Refrigerating and Air-Conditioning Engineers, HVAC Design Manual, 2003. The

    design conditions for the air-conditioning system are as below:-

    i. inside Design Conditions

    The room air conditions is design to be maintained at 75F 2F (24C 1C) of

    Dry Bulb temperature and 55% 5% Relative Humidity

    ii. outside Ambient Conditions

    Design calculations have been based on outside condition of 92F (33.3 C) Dry

    Bulb and 80F (26.7C) Wet Bulb temperature.

    iii. Fresh Air Ventilation

    The amount of fresh air for ventilation purposes shall be taken as not less than 20

    cfm1 per person

    1 Cfm=cubic feet per meter

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    3.2 Data collected from case studied building.

    Figure 1: Cooling load profile of studied building

    From the data collected on 20 August to 22nd August 2009, the average cooling load

    studied building is on average of 103 tonnes. Therefore, the sizing for solar thermal

    absorption chiller or gas fired absorption chiller should be design to supply the cooling

    load profile (Figure1) and meet the overall requirements of air-conditioning system. This

    is to ensure that the design would be more energy efficient and air-conditioned area will

    be supplied as per specification that has been determined in the early stage according to

    clients project brief.

    104.59

    115.49118.91

    123.01 121.15 120.01 118.67121.96

    80.24

    93.88

    0.00

    20.00

    40.00

    60.00

    80.00

    100.00

    120.00

    140.00

    08/21/09 08:00 AM

    08/21/09 09:00 AM

    08/21/09 10:00 AM

    08/21/09 11:00 AM

    08/21/09 12:00 PM

    08/21/09 01:00 PM

    08/21/09 02:00 PM

    08/21/09 03:00 PM

    08/21/09 04:00 PM

    08/21/09 05:00 PM

    Ton

    ne

    Time

    Cooling load profile for Klinik Kesihatan Medan Maju

    Tonne

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    3.3 Electricity cost analysis

    Figure 2: Electricity cost for year 2007

    Figure 3, above illustrates the billing period of year 2007. The data received from the

    end user starting from month of June 2007. The graph shows that the minimum

    energy usage occurs in the month of September with 30873kWh. Average energy

    usage for six months period was 34708kWh with the total of 208248kWh (RM67,

    264.00). The highest energy usage occurs during the month of October which was

    38765kWh. This scenario happens most probably due to high cooling demand of air-

    conditioning and extension on operating hours from 8 hours to 10 hours daily.

    However, this would only be the predicted reason against the profile shown. Detail

    study need to be investigated in the future to make the best annotate on the scenario.

    35,563.00

    35,920.00

    30,873.00

    38,765.00

    35,694.00

    31,433.00

    0

    5000

    10000

    15000

    20000

    25000

    30000

    35000

    40000

    45000

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

    kWh

    or

    RM

    Total electricity usage (kWh) and cost (RM) year 2007

    Total electricity kwh

    Electricity Cost (RM)

  • SOLAR ABSORPTION CHILLER

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    Figure 3: Electricity cost for year 2008

    Figure 3, illustrates the electricity cost and kWh consumed in year 2008, it can be seen

    the maximum electricity usage were for the on month of October which is 37,804kWh

    and cost RM15, 016. Again, the electricity profile in kWh had shown marginally pattern

    and no abrupt changes in the energy consumption.

    Figure 4: Electricity cost for year 2009

    Figure 5, illustrated the energy consumed by the studied building in year 2009. From the

    figure above, the energy was increase dramatically on month of June due to new tariff

    imposed from TNB which was from RM 0.323 per kWh to 0.408 per kWh.

    0.00

    5,000.00

    10,000.00

    15,000.00

    20,000.00

    25,000.00

    30,000.00

    35,000.00

    40,000.00

    jan Feb Mar April Mei June July Aug Sept Oct Nov Dec

    kWh

    or

    RM

    Month

    Total electricity usage (kWh) and cost (RM) year 2008

    Total Electricity kWh

    Electricity cost (RM)

    0.00

    10,000.00

    20,000.00

    30,000.00

    40,000.00

    50,000.00

    60,000.00

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

    Kw

    h o

    r R

    M

    Month

    Total electricity usage (kWh) and cost (RM) year 2009

    Total Electricity usage kwh

    Total electricity costRM

  • SOLAR ABSORPTION CHILLER

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    4 BASIC PRINCIPLE OF SOLAR THERMAL ABSORPTION CHILLER

    In this report, the solution on adapting solar thermal absorption cooling for the air-

    conditioning systems start by preliminary discussion on the basic concept of solar

    cooling absorption chiller, the collectors and various type of absorption liquid. Basically

    the absorption chiller consists of four components which include the generator,

    condenser, evaporator and the absorber (Figure 5) .Primarily, the cooling effect is based

    on the evaporation of the refrigerant for (i.e water mixture from the absorption chiller).

    The water will evaporate in the evaporator at very low pressures. Secondly, the

    vaporised refrigerant is absorbed in the absorber, thereby diluting the H2O/LiBr (water

    and lithium bromide) solution. To make the absorption process efficient, the process has

    to be cooled. Thirdly, the solution is continuously pumped into the generator, where the

    regeneration of the solution is achieved by applying driving heat (e.g. hot water) and

    finally, the refrigerant is then leaving the generator by this process condenses through

    the application of cooling water in the condenser and circulates by an application of an

    expansion valve again into the evaporator.

    Figure 5: Basic principle of absorption chiller, http://www.raee.org/climatisationsolaire/doc/technical_overview_of_active_techniques.pdf

    For this study an ideal framework of solar thermal absorption cooling is as per Figure 6.

    Where the heat transmitted from the solar collector to the hot water storage tank by

  • SOLAR ABSORPTION CHILLER

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    means a driving heat for the absorption chiller. However if the solar radiation is not

    enough to generate the heat as for this case assume that the solar radiation might drop

    below 700 kJ (the solar intensity is insufficient to start the absorption chiller) therefore

    the gas boosted system will be operated. Then with the driving heat in the solar collector

    the absorption chiller will start to operated with a basic concept as discussed above. The

    heat from the evaporation then cooled by means of cooling tower and the chilled water

    collected in the chilled water storage before the chilled water being distributed in for

    number of air handling units.

    E-1E-2

    E-3

    E-5

    E-7

    E-8

    E-9

    E-10

    P-10

    P-13

    P-14 P-18

    P-19

    P-20

    E-12 E-13 E-14

    E-15

    P-21

    P-25

    P-20 P-26

    P-28

    P-29E-16

    Solar CollectorHot Water Storage Tank

    P-30

    P-13

    P-14

    P-31

    P-30

    P-32

    E-18

    Gas Boosted System Cooling Tower

    Chilled Water Storage Tank

    P-33 P-34

    Fan Coil AHU1 AHU2 AHU3

    E-19

    AHU4

    P-20

    Figure 6: The typical design of solar thermal absorption cooling

  • SOLAR ABSORPTION CHILLER

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    5 Comparative analysis on Absorption liquid

    There were many types of absorption liquid could be used for this system. However, two

    major liquid normally available in the markets and they are the lithium bromide

    water (LiBr-H2O) and ammonia-water (NH3-H20). These two solutions have their pros

    and cons as below:

    The coefficient of performance (COP) for the H2O_NH3 system is lower than for

    the LiBr_H2O system. Generally, H2O_NH3 systems operate at a 10-15% lower

    solar fraction2 than LiBr_H2O systems.

    H2O_NH3 requires a higher generator inlet temperature. Generally, LiBr_H2O

    absorption units require generator inlet temperatures of 70C-88C, while

    H2O_NH3 absorption units require temperatures of 90C- 88C; which results in

    the H2O_NH3 cooling systems achieving a lower COP when using Flat-plate

    collectors. It requires higher pressures and hence higher pumping power.

    H2O_NH3 more complex system requiring a rectifier to separate ammonia and

    water vapor at the generator outlet is required.

    There are restrictions on in-building applications of ammonia-water cooling units

    because of the hazards associated with the use of ammonia.

    Therefore from this reviews, the suitable solution for this project will be the lithium

    bromide water applications and with a driving heat of (80C to 100C) as per figure

    7.

    2 The percentage of a building's seasonal energy requirements that can be met by a solar energy device(s) or system(s). (http://www.daviddarling.info/encyclopedia/S/AE_solar_fraction.html)

  • SOLAR ABSORPTION CHILLER

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    Figure 7, The various type of absorption chiller. http://www.raee.org/climatisationsolaire/doc/technical_overview_of_active_techniques.pdfdate viewed 4th June 2009

  • SOLAR ABSORPTION CHILLER

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    6 Characteristic of the absorption chiller to be employed

    The absorption chiller estimated to be installed with this particular building would be

    approximately 100 RT (Refrigerant tonne). This is to match the current load profiled of

    the purposed building. The specification of absorption chiller is per Table 1 below. As the

    manufacturer could provide 108 tonne model, therefore in this studied building the

    analysis will be based on 108 tonne absorption chiller.

    Table 1: Specification of absorption chiller

    6.1 Types of solar Collectors

    Listed below are some of the types of solar collector available in the market

    i. Flat-plate collectors;

    ii. evacuated tube collectors;

    iii. dish type concentrating collectors;

    iv. solar pond; and

    v. photovoltaic

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    Base on the ASHRAE Handbook, of HVAC Systems Equipment the suitable solar collector

    for this project will be the evacuated tube collector due to high efficiency for the air-

    conditioning applications (Figure 8). The efficiency of collectors could be reach

    approximately at 0.05 to 0.09 (m2.K/W)

    Figure 8: Collector Efficiency of Various Liquid Collectors.

    6.2 Advantage and Disadvantages of Evacuated tubes:

    Advantage Disadvantage

    High operating temperature can be

    achieved that with a flat plate collectors.

    (Higher temperature suitable for solar

    cooling).

    High stagnation temperature with

    corresponding demands on all materials

    used near the array an on the heat transfer

    fluid

    Reduce thermal losses that with flat plate

    collectors due to excellent heat insulation

    Considerably higher initial cost from a flat

    plate collectors

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    Higher energy yields those flat plate

    collectors with the same effective absorber

    area.

    Higher cost on the available solar heat at

    medium operating temperature range,

    since cost advantages only at higher

    operating temperatures.

    Close compact construction of the collector

    which will require no interior insulation

    material, and thus no penetration of

    moisture or dirt into the collectors.

    From this pros and cons of the evacuated tube we can conclude that the evacuated tube

    have higher efficiency compared to flat plate, however, the cost is relatively high and not

    suitable for a low temperature applications. Figure 9 illustrate the cross-section of the

    evacuated tube with a direct flow concept.

    Figure 9, cross section through a direct flow vacuum tube

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    6.3 Governing the temperature of Solar Collector for the Application

    Depending on the flow rate of the hot water and the average solar radiation at the

    proposed location two method can be used to determine the temperature namely:

    i. High Flow

    The usual flow (high-Flow, referred as high flow means that the nominal

    flowrate of the total field amounts to about 40-80 litres per hours per m2 of

    the collector surface. This mode is chosen if all the collectors are parallel-

    connected (Figure 10). This avoids dead zones which gives only negligible

    contribution to the collection of heat (Peuser.F.A et al, 2002). The formulae to

    calculate the temperature different in the collector are as follow:

    )/( tyheatcapaciFlowrateHeatfkuxT

    For example

    Solar radiation: 1000 W/m2

    Efficiency of the collector is 60%

    Heat capacity of 60/40 mixture water/antifreeze: 3.7 KJ(kg.K)

    K

    KkgJms

    kg

    msJ6.14

    /370023600

    40

    )2/(600

    By using the usual flow method the temperature different is small for this case

    the temperature different is 14.6K (14.6C)3.

    3 1 K = 1 oC (Engineering Toolbox, 2010)

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    Figure 10 Collector Field Layout with On-Roof Installation (parallel) downloadcenter.wagner-solar.com/download.php- Germany

    ii. Low Flow

    The low flow mode is characterized by a nominal flow rate of 12-20 litres per

    hour per collector m2. This mode requires that, at least partly, a serial connection

    (Figure 11) is applied, so each collector receives a minimal of flow.

    By the formulae as above the temperature different is approximately 29.2K to

    48.6K

    Therefore for this study the most suitable method for the applications is the low

    flow due to the methods on installing the collector will be serial method due to

    high temperature required to generate the absorption chiller (80C-110C).

    Figure 11 Collector Field Layout with On-Roof Installation (series) downloadcenter.wagner-solar.com/download.php- Germany

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    Figure 12: Monthly variation of solar radiation, Assilzadeh et al, (2005), Journal of Renewable Energy

    )/( tyheatcapaciFlowrateHeatfkuxT

    Refer to Figure 12, the average solar radiation = 700KJ/hr-m2 (by taking 60% of

    efficiency = 420KJ/hr m2)

    The solution is 100% water and does not required antifreeze (assume 10,000kg)

    Specific heat of water = 4.178(KJ/kg/K) (Engineering toolbox,2008).

    K

    KkgJms

    kg

    msJ2.36

    /417823600

    10000

    )2/(000,420

    As per calculation above, therefore the solar collector temperature is 36.2K

    (36.2C). For this study the temperature required for the solar collector to drive

    the absorption chiller is 86 C (122 C4-36C) (hot water temperature). However

    further simulation (e.g TRANSYS) need to be entailed in order to achieve

    accurateness data for the actual design.

    4 The maximum temperature for the solar collector as per maximum solar radiation for Malaysia

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    Figure 13: The temperature of solar collector

    6.3 Solar insolation5 for Kuala Lumpur for studied evacuated tubes.

    Analysis done to size up number of evacuated tube to meet the current cooling load of

    studied building. The average solar insolations were base on NASA approved website of

    US Government and manufacturers data. From this website and manufacturers data it

    is that estimated 100 sets of evacuated tubes could supply 30 tonne of cooling, therefore

    for 100 tonne of cooling the number of evacuated tubes needed will be 400 sets. The

    calculation for solar insolation could provide cooling were as the table and formula

    below.

    5 The amount of electromagnetic energy (solar radiation) incident on the surface of the earth. ref : http://www.apricus.com/html/solar_collector_insolation.htm

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    The average solar insolations were estimated for each hour starting from 8.00am to

    5.00pm daily. Each hour, the solar fraction analysis were estimates to evaluate the

    performance of solar collector to provide cooling. According to this analysis, the peak

    solar for cooling with 400 sets of collectors is at 2.00pm which could produce 144.85

    tonne of cooling. The manufacturers data was according to Table 2 below shown that the

    gross area of purposed solar collector is 4.08m2 .The area need to install the collector for

    air-conditioning of this building would be 400sets x 4.08m2 =1,632 m2. Therefore, this

    would be crucial for the studied building to provide area for the collector. Further

    analysis and discussion with the architect need to be done in other to coordinates this

    new installation. However, to surmount problems associated with the available roof area,

    for the preliminary of first this first project on solar absorption chiller only the common

    area will air-conditioned as the cooling load will be much lesser.

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    Table 2: Specification of Solar Collector

    Figure 14: Solar Insolation and Cooling load of the studied building.

    Figure 13, illustrates the solar fraction (how much solar could produce cooling) versus

    the cooling load of the building. From this analysis, it is noted that the system need a

    back-up power to overcome the problems associated with lower solar fraction which in

    this case it would be at 8.00am to 11.00am. Henceforth, if the propose project area could

    supply a natural gas to fire the absorption chiller, this would be a best practice to adapt.

    0.00

    20.00

    40.00

    60.00

    80.00

    100.00

    120.00

    140.00

    160.00

    Ton

    ne

    Time

    Estimated Cooling Load & Solar Insolation

    Solar Insolation (Tonne)

    Cooling Load (Tonne)

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    However, if natural gas is not accessible, therefore the hybrid system shall be used.

    Hybrid system shall be the VRV system or water cooled package which would not

    involved major impact on the structured of the whole building. Figure 13, illustrated the

    proposed load profile for proposed project area with availability of natural gas which

    could operates in hybrid mode with the solar collectors.

    Figure 15: Purposed load profile between solar and direct fired absorption chiller.

    7 EVALUATION OF OPTIONS

    The evaluation was done by making a comparison different types of cooling air-

    conditioning i.e solar absorption chiller and an air-cooled chiller, air-cooled split unit,

    water cooled chiller and direct fired absorption chiller. The outcomes of the evaluation

    discussed as per subject below:

    7.1 Economic Evaluation

    From Table 2, the analysis done on comparing the energy cost, operating cost and

    maintenance cost of the whole project. The life cycle cost analysis done for 20 years

    duration in which the capital expenditure and operation expenditure are incorporated

    throughout the years. Investments cost incurred on adapting the solar thermal

    absorption chiller would be RM27,000 per ton of cooling and the gas fired absorption

    0

    20

    40

    60

    80

    100

    1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

    Load

    Pro

    file

    (R

    T)

    Hour end

    Proposed load profile between solar and direct fired.

    Solar

    Direct Fired

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    chiller would be RM10,700 per ton of cooling. This can be seen that the life cycle cost of

    gas fired system is cheaper by more that half the life cycle cost of the solar absorption

    chiller. Henceforth, to be more viable and holistic approach the absorption chiller would

    be more practical to be adapt in the building were there are waste heat and natural gas is

    available.

    Table 3: System comparison for Klinik Kesihatan.

  • 7.2 Social Evaluation Generally the solar absorption chiller is more sustainable systems which use less usage

    of electricity power. The scope of this project will be the installation of the solar cooling

    for the existing building. This project however would become as a benchmark of new

    design features for the government offices in Malaysia. If the project is successful, might

    be in the future it would increase a capacity building of new renewable technology

    implementation for the building in Malaysia. New technology most probably needed a

    competent worker to install the systems, thus, this project would create job

    opportunities in Malaysia and would increase the market forces in the photovoltaic

    industries. Most importantly, in the aspect on improving the productivity of the

    employees, cleaner air from the STAC would achieve the indoor-air quality, hence

    improving the quality of work.

    8 CONCLUSIONS AND RECOMMENDATIONS

    Solar thermal Absorption chiller will be feasible to adapt due to the high of energy saving

    approximately i.e 50% saving compared to conventional air-cooled package unit that is

    normally installed in the Government hospital building in Malaysia. The payback period

    is approximately 9 years of the total investment if the solar absorption chiller

    implemented in the studied building. However, if natural gas is available in the proposed

    area, the payback period will be achieve in 3 years time with the application of gas-fired

    absorption chiller. Although, the installation costs is very high, the CO2 emission

    reduction could be achieve at 50% compared to conventional systems. It is

    recommended to implement the solar absorption chiller in the hospital building and shall

    be hybrid with the electric power air-conditioning system to make sure that the system

    will operates continuously. Recommendations shall include the actual project done in

    one of the Government hospital building in Malaysia. From there, to obtain an actual

    data such as solar fraction of receives from the collectors on the proposed area would be

    more accurate and reliable. Furthermore the funding in research and development of this

    particular system should be a priority.

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    9 REFERENCES

    Azni Zain Ahmed, 2008, Integrating Sustainable Energy in Buildings: A Case Study in Malaysia, FAU Conference, Copenhagen, Denmark, 14-15 May; www.fau.dk/Azni%20FAU%20Conference%20Paper.doc , viewed 16 June 2009 Engineering Toolbox, http://www.engineeringtoolbox.com/water-thermal-properties-d_162.html , Viewed 23/06/09 GROSSMAN, G., 2002 Solar-powered systems for cooling, dehumidification and air-

    conditioning. Solar Energy, 72, 53-62. F. Assilzadeh, S.A. Kalogirou, Y. Alia, K. Sopian 2005, 'Simulation and optimization of a

    LiBr solar absorption cooling system with evacuated tube collectors', Renewable

    energy, vol. 30, pp. 1143-59.

    Rhnalpnergie-Environnement, 2008, Basic principle of Solar Cooling. http://raee.org/climatisationsolaire/gb/presentation.htm retrieved 7 June 2008

    The Energy Commission of Malaysia, Government Of Malaysia, 2007

    http://www.st.gov.my/tariff.html#TNB retrieved on 7 June 2009

    The Ministry of Energy, Water and Communication, Government of Malaysia, 2007 www.ktak.gov.my, retrieved on 7 June 2009

    LI, Z. F. & SUMATHY, K. (2000) Technology development in the solar absorption air-conditioning systems. Renewable and Sustainable Energy Reviews, 4, 267-293

    Mechanical Engineering Branch, 2006 http//:www.rakan.jkr.gov.my, on 11 June 2009

    National Electricity Board, Government of Malaysia, 2007. (www.tnb.com.my), view on

    11 June 2009 NASA, 2009, US Government. http://eosweb.larc.nasa.gov/ date viewed on 1 Disember

    2009

    Public Works Department, 2007, Ministry Of Works, Malaysia, www.jkr.gov.my, retrieved

    on 5 June 2009

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    Appendixes:

    Appendix 1: Natural gas tariff in Malaysia

    http://www.st.gov.my/index.php?option=com_content&task=view&id=2492&Itemid=1

    Appendix 2 : Electricity tariff (Medium commercial )

    Source : The Energy Commission of Malaysia,2007

    http://www.st.gov.my/tariff.html#TNB retrieved on 7 August 2009

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    Appendix 3: Mean emission for electricity in Malaysia . Source: Energy Centre Malaysia, http://www.ptm.gov.my