2013 IEEE Conference on Systems, Process & Control (TCSPC2013), 13 - IS December 2013, Kuala Lumpur, Malaysia

Energy Efficiency Benchmarking in

UiTM Engineering Complex Shah Alam

#1 . #1 ·#2 I '1#1 S R M S B k·#1 Z.M. Zain#l, M.B.A.Aziz ,A.H. KaSSlm ,R.A.Hadl ,I. sma! , . . . . a 1

I Faculty of Electrical Engineering 2 Facilities Management and Development Centre

Universiti Teknologi Mara 40450 Shah Alam

Selangor Darul Ehsan

Abstract- Energy efficiency implementing strategy requires

various approaches for different condition to increase the

effectiveness. The energy efficiency normally refers energy

usage without wastage. Normally, certain reference or

benchmarking to certain standard will be used such as building

energy index (BEl). Two new indexes were introduced in this

paper namely Effective Building Energy Index (EBEI) and

Specific Building Energy Index (SBEI). This paper presents the

benchmarking additional approach so as to reduce energy

wastage in Engineering Complex, UiTM Shah Alam. BEl for

this complexs was found to be 149 kWh/m2.year and EBEI is

found to be 186 kWh Im2.year. The SBEI was found to be 0.207

kWh/m2.year for an occupant. With various approach

discussed in this paper, an expected energy reduction of 20%

can be achieved.

Keywords- Energy efficiency, zero energy wastage, strategy

I. INTRODUCTION

Thermal comfort is normally the main reason of having an air conditioning system for a building. Other purposes include air circulation or ventilation, air purifying and dehumidifying or humidifying. Normally an air conditioning system will consume significant percentage of electrical energy. For a building in hot and humid climate like Malaysia, energy consumption is very high thus prone to energy wastage. One of the objectives of Malaysian energy policy is to promote the efficient utilization of energy and to discour�ge wasteful and nonproductive pattern of energy consumptIOn [1]. Energy instead of money is the real currency of the world [2]. In a study, the average building energy index was found to be 256 kWh/m2/year [3] For energy efficiency, a standard need to be introduce as a reference. Malaysia Standard MS 1525 is a guide line to encourage energy efficiency. Nevertheless, there is no value

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such as Building Energy Index (BEl). The standard given is not provided the targeted numerical value of energy index. It only provides the final condition such as the design temperature or humidity but doesn't indicate the amount ?f energy that is required. A well-designed AHU system will manage to control the temperature, humidity, air motion, and thermal radiation as well as the odor, dust, noise and vibration [4, 5, 6]. Effective Building Energy Index (EBEI) is a good indicator of energy performance but other index is also important. In this paper, two new indexes have been introduced which will complement the traditional Building Energy Index. The first is Effective Building Energy Index (EBEI) where equivalent energy due to maximum demand is also required. Another index is the consideration of occupant staying in the building. The index is known as Specific Building Energy Index (SBEI). The paper is divided into introduction, system description, method, results and discussion and lastly the conclusion.

II. SYSTEM DESCRIPTION

Electrical system forms the sole energy consuming device and can be explained building Energy Index (BEl). The systems with 10 substations I transformer incorporate the data acquisition system where data were taken every 15 minutes. There are 158 Air Handling Units (AHU) and 980 Fan Coil Units (FCU) with total power need of more than 1.1 MW. The estimated power demand for other non-air conditioning related is about I MW. Chillers and related pumps will account to power maximum demand of about 2.4 MW. The total load maximum demand is expected to be about 4.5 MW. The best BEl practice recommended by Malaysian Standard is 135 kWh/m2/year [7]. Neverthel�ss, there is no reference to the maximum demand (MD) which also being charged by national service provider TNB and number of occupants which has implication on the energy usage.

2013 IEEE Conference on Systems, Process & Control (TCSPC2013), 13 - IS December 2013, Kuala Lumpur, Malaysia

III. METHOD

Nonnally, determining the appropriate energy for a building is by conducting energy audit. But, in this paper, the appropriate energy suggested is divided into three stages; Firstly, by increasing the awareness to the maximum. [t is expected that 10 % energy reduction can be achieved. The current practice of supplying chilled water is that all air handling unit (AHU) be provided with chilled water. The second strategy will be to supply chilled water upon request. It is expected that with this strategy, a further 10 % energy reduction can be achieved. The third strategy is to conduct energy auditing for locations that does not comply with the total 20 % of energy reduction after strategy 1 and 2 being conducted. Data was acquired from the data logger available in the system. The every 15 minutes data obtain for one month of October 2013 was analysed. Based on the analysis, an achievable target was.

IV. RESULTS AND DISCUSSION

TABLE I ENERGY AND MAXIMUM DEMAND

E n ergy(kWh ) MD(kW) LF RM RMTarget

TES1 478065 1689 0.38 192913 173621

TES2 100689 258 0.52 38106 34296

TES3 135637 377 0.48 52086 46877

B1 85191 217 0.53 32188 28970

B2 96405 296 0.44 37751 33976

B3 100985 289 0.47 38992 35093

B4 138666 377 0.49 53032 47729

B5 152173 385 0.53 57461 51115

T1 114667 304 0.51 43637 39274

T2 121554 296 0.55 45594 41035

Sum 1524033 4489 0.46 591759 5325&3

MD(kW) for 10 Substation 1800

1 600

1400

1200

100J

800

600

400

200

0 TES1 TES2 TES3 61 62 63 64 65 11 T2

Fig. I Maximum demand or 10 substations

Figure I shows the maximum demand for 10 selected substations. From the graph, the higher value for maximum demand is for TESI . Others substation show the maximum demand below than 400 kW.

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Electrical Load Factor for 10 Selected Locations

0.60

0.50 r--- - - - r-- -

0.40 r---- - - - r-- -

0.30 - - - - r-- -

0.20 - - - - r-- -

0.10 - - - - r-- -

0.00 TE51 TE52 TE53 Bl B2 B3 B4 B5 T1 T2

Fig. 2 Electrical load factor (LF) for 10 selected locations

RM for 10 Selected Locations 250000 -,---------------------

200000+--------------------

150000 +-1 __ ------------------

100000+-1 __ ------------------

50000 +-1 __ ---1 __ ------__ .--

o +-'---.--"--.,...--.----,-TE51 TE52 TE53 81 B2 83 84 B5 T1 12

Fig. 3 RM for 10 selected locations

TABLE 2 MONTHL Y, DATL Y AND YEARLY ENERGY

O ctober 2013 per Month per Day per Year

Energy(kWhj 1524033 49162 17944260

MD(kW) 4248 4248 4248

Load Factor 0.48 OA8 0.48

kWh per m2 12.70 0.41 149.54

kWh per person 169.34 5.46 1993.81

RM/m2 4.93 0.16 58.06

Total RM 591759 19 089 6957488

RM/person 55.8 2.12 774

Effective Energy(kWh l 1895564 61183 22331591

Building Energy Index 15.81 0.51 185.10

Specific Building Energy Index (kWh/m2/per�on/year) 0.207

From Table 1 and Table 2, a few deductions can be made. TES 1 which is the chiller plant form the highest energy consuming sector of the engineering complex. The maximum demand is also the highest, with the value of 1689 kW. This happen when 3 chillers is running. Together with TES2 and TES3, the MD was found to be 2286 kW. TES2 is power consumption for various distribution pumps and TES3 is power consumption for the cooling towers. The table also shows that the electrical cost for the complex with all using CI tariff amount to RM591 ,759 for the month

2013 IEEE Conference on Systems, Process & Control (TCSPC2013), 13 - IS December 2013, Kuala Lumpur, Malaysia

of October 2013. The overall load factor (LF) is 0.48 which nis below 0.5 meaning that the distribution is poor. A cost reduction of 10% will reduce the electric bill by nearly RM60K. From a general observation audit, a 10% reduction can easily be achieved by awareness from all level of management, staff and students. Islamic motivation and approach can be the driver for zero wastage and saving.

The second stage of the energy efficiency strategy is by supplying air conditioning need to the various locations, not by default but by request. Since the AHU can be managed and control by the Energy Management System, only those who request will be provided with air-conditioning service.

If after taking strategy 1 and strategy 2, the 20% reduction in electricity cost is not met, then energy audit will investigate. If the audit team is satisfied that all measurement has been taken about the energy utilization without wastage, a new energy efficiency benchmark will be established.

Table 2 show the maximum demand of 4248 kW and energy of 1.524 GWh per month. Energy per person 169.34 kWh per month and energy per m2 space is 12.7 kWh/m2• Considering the maximum demand cost, the effective energy building index is 186.10 kWh/m2/year. Specific Building Energy Index (SBE\) was found to be 0.207 k Whim 2 Iperson/year.

It can be seen that only 9% of the time is during the off-peak while 91 % is during the peak time. In order to take the advantage of the cheap off peak rate, significant amount of load should be shifted to the off peak time. The load factor will then improve to a significantly higher value.

IEnergy(kW h ) i2

6% 6% 9%

Fig. 4 Percentage of energy used

The chart in Fig. 4 shows the percentage of energy utilization at the engineering complex. The graph in Fig. 5 shows a typical load profile as on 21 October 2013 (Monday). When the third chiller unit was turn on, the electrical increases by about 650 kW, due to increase in the cooling load demand. If the cooling load extra demand can be fulfill by retrieving from the ice cell storage, then the load factor can be improved.

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�

Load Profile for Engineering Complex From 0000 hr to 2400 hr

4500

4000

3500

3000

2500

2000

1500

1000

500

o

Fig. 5 Load Profile for a typical working day (3 October 2013)

From Fig. 5, the maximum demand on 3 October 2013 was found to be between 3.00 pm to 5.00 pm. The area under the curve was shaded to represent the energy which is cumulative in nature.

V. CONCLUSION

Building energy index as a means of benchmarking of energy consumption in building is relevant but not good enough. Other additional index which consider the implication of maximum demand and the number of occupants in the building need to be included. The building energy index for the Engineering Complex was found to be 149 kWh/m2.year. and the effective building energy index is 186 kWh/m2.year. The specific building energy index (SBE\) is 0.207 kWh/m2.year. As a benchmark, the recommended energy efficient building should have not more than building energy index (BEl) of l35 kWh/m2/year, effective building energy index (EBEI) of 150 kWhlm2/year.

VI. ACKNOWLEDGEMENT

The authors would like to thanks and acknowledge the financial support from the Faculty of Electrical Engineering and Research Management Institute (RM\) under RIF Fund 600-RMIIDANA 5/3/RIF (663/2012), Universiti Teknologi MARA, Shah Alam.

VII. REFERENCE

[I] Ministry of Energy, Water and Communication Malaysia, "National Energy Policy Objective," 2005.http://www.ktkm.gov. my/templateOI.asp

[2] C. Beggs, Energy: Management, Supply and Conservation, Butterwort:Heinemann. 2002

[3] A. Z. Ahmad, "Day lighting and Shading of Thermal Comfort in Malaysian Buildings," Ph.D dissertation, University of Hertfordshire, London, 2000

[4] Sabarinah, S. H. Ahmad, "Thermal Comfort and Building Performance of Naturally Ventilated Apartment Building In the Klang Valley", A Simulation Study , WATER AND Proceedings of the Energy in Building (Sustainable Symbiosis) Seminar, 2006.

2013 IEEE Conference on Systems, Process & Control (TCSPC2013), 13 - 15 December 2013, Kuala Lumpur, Malaysia

[5] Z. M. Zain, M. N. Taib and S. M. S. Bald, "Hot and Humid Climate: Prospect for Thermal Comfort in Residential Building", Desalination 209: 261-268, 2007

[6] Malaysian Standard MS 1525, "Code of Practice on Energy Efficiency and Use of Renewable Energy for Nonresidential Buildings", Department of Standards Malaysia, 2001.

[7] "Guidelines for Energy Efficiency in Building". Ministry of Energy, Telecommunication and Posts Malaysia, 1989.

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