This paper presents the achievements of implementing smart operations strategies for air-conditioning (A/C) and lighting systems in Justice Palace Complex (JPC), Kuwait during the summer 2007. The peak load of this building was 3700 kW. The achievements are summarized as direct savings between 13:00 and 22:00 h by closing supply and return air fans of 52 air-handling units with a connected load 400 kW, and an additional saving of 550 kW during the same period by optimizing the cooling production and distribution. Also an all time saving of 22 kW by de-lamping, and additional saving of 27 kW through TDC of lighting were achieved. In conclusion project achieved an overall reduction in power demand of around 20% between 13:00 to 17:00 h and reduction ranging from 7% to 15% between 17:00 to 20:00 h

Al-Hadban, Y.

Al-Mulla, A.

Al-Nakib, D.

Alasseri, R.

Maheshwari, G. P.

English

Texas A&M University

  
SMART OPERATIONS OF AIR-CONDITIONING AND LIGHTING SYSTEMS IN A GOVERNMENT BUILDING 
FOR PEAK POWER REDUCTION 
 
Y. Al-Hadban G.P. Maheshwari D. Al-Nakib A. Al-Mulla R. Alasseri 
Associate Research 
Scientist 
Senior Research 
Specialist 
Senior Research 
Associate 
Associate Research 
Scientist 
Principal Research 
Technician 
 
Department of Building and Energy Technologies 
Environment and Urban Development Division 
Kuwait Institute for Scientific Research 
P.O. Box 24885, 13109, Safat, Kuwait 
yhadban@safat.kisr.edu.kw 
 
ABSTRACT 
This paper presents the achievements of implementing 
smart operations strategies for air-conditioning (A/C) and 
lighting systems in Justice Palace Complex (JPC), 
Kuwait during the summer 2007    The peak load of this 
building was 3700 kW.  The achievements are 
summarized as direct savings between 13:00 and 22:00 h 
by closing supply and return air fans of 52 air-handling 
units with a connected load 400 kW, and an additional 
saving of 550 kW during the same period by optimizing 
the cooling production and distribution. Also an all time 
saving of 22 kW by de-lamping, and additional saving of 
27 kW through TDC of lighting were achieved. In 
conclusion project achieved an overall reduction in 
power demand of around 20% between 13:00 to 17:00 h 
and reduction ranging from 7% to 15% between 17:00 to 
20:00 h. 
 
Key words : Peak power, air-conditioning, time-of -day 
control, de-lamping. 
 
INTRODUCTION 
In Kuwait, national peak power, primary controlled by 
air-conditioning (A/C) of the buildings commonly occur 
at around 15:00 h.  The average power increase between 
13:00 and 15:00 h is 4% that amounts to approximately 
400 MW.  Considering that most of the government 
offices operate between 07:00 and 14:00 h, and their total 
power demand exceeds 600 MW; the national power 
demand in the country can be frozen at 13:00 h level by 
effectively operating the A/C and lighting in the 
government buildings.  During the summer 2007, smart 
operation strategies for A/C and lighting systems were 
developed and tested in a number of governmental 
buildings in Kuwait as one of the solutions to reduce the 
national peak electrical power demand.  The smart 
operation strategies implemented in these buildings 
included Pre-Closing Treatment (PCT) between 13:00 
and 14:00 h and Time-of-Day Control (TDC) after 14:00 
h.  Also de-lamping was carried out in some of the 
buildings to readjust the higher than recommended 
illumination levels.  This paper presents the findings of 
such a scheme implemented in the Justice Palace 
Complex (JPC) during 2007 summer.  More importantly, 
it presents an approach and methodology for 
implementation of this scheme that can be followed by 
countries in the region. 
 
JPC building, commissioned in 1985, houses judicial 
organs and their agencies.  The building is square in plan 
and has a sky-lit courtyard in its center.  It has clear-
single glazed windows and un-insulated walls and roof.  
Occupancy period for this building is between 7:30 and 
14:00 h, however, several zones, such as court rooms are 
occupied after working hours.  It has a peak load of 
around 3,700 kW.  The fans of the air-handling units 
(AHUs) and fan coil units (FCUs), and the secondary 
chilled water pumps run round the clock.  Also the 
number of chillers in operation is changed only on 
seasonal basis.  JPC building has a BAS that has on/off 
facility for AHUs but there is no specific control for 
lighting system. 
 
DESCRIPTION OF AIR-CONDITIONING AND 
LIGHTING SYSTEMS 
Air-conditioning and lighting systems are the major 
power users in the JPC like in any other building in 
Kuwait and the region.  Although there are 
miscellaneous other users, the present study has been 
confined to A/C and lighting systems. 
 
Air-Conditioning System 
JPC has a central A/C system with recently replaced 
water-cooled centrifugal chillers.  Three chillers each 
with a cooling capacity of 854 RT are expected to meet 
the building peak cooling demand.  Additionally, there is 
a stand-by chiller.  A single set of chilled water pumps, 
unlike the common practice in modern A/C systems 
using a combination of primary and secondary pumps, 
circulate the chilled water at a constant flow between the 
chillers and the miscellaneous users.  A schematic of the 
cooling production and distribution equipment is shown 
in Fig. 1. 
 
ESL-IC-10-10-16
Proceedings of the Tenth International Conference for Enhanced Building Operations, Kuwait, October 26-28, 2010
  
 
Figure 1.     Schematic of air-conditioning system in JPC 
 
The connected load for the different motors is given in 
Table 1.  The connected load for the cooling production 
and distribution auxiliaries (CPADA) is 1118 kW, while 
the same for the three chillers is 1,920 kW.  The air 
distribution through 98 AHUs and 900 fan-coil units 
(FCUs) is with a constant flow.  Each AHU has one 
supply air fan and two return air fans.  The connected 
load of all the supply air fans is 638 kW while that of 
return air fans is 342 kW.  In addition, 900 FCUs has a 
connected load of 180 kW.  Thus, the total connected 
load of the air distribution system is 1160 kW.  Also, 
there is a booster pump of 45 kW for feeding chilled 
water to 900 FCUs.  The AHUs and FCUs are with 3-
way flow regulating valves, accordingly the chilled water 
flow in the system was constant. 
 
Table 1. Connected Load of Major Power Users in 
JPC Building 
Equipment Quantity 
Unit 
Power 
( kW) 
Total 
Power 
(kW) 
Chillers 3+1 640 1920 
Chilled water pumps 3+1 160 480 
Condenser water pumps 3+1 160 480 
Cooling tower fans 3+1 37/12 111 
FCU chilled water 
pump 1+1 45 
45 
Air-handling units 
- Supply air 
fans 
- Return air 
fans 
98 
196  
2.2-22 
0.17-17 
638 
342 
Fan coil units 900  180 
Lighting lot  915 
      Total 5111 
+1=Stand by 
 
Lighting System 
Lighting system in the interior of the complex comprises 
mostly of energy-efficient fluorescent tubes.  However, 
the illumination level in many areas exceeds the 
recommended values specified by the Ministry of 
Electricity and Water (MEW) through the Energy 
Conservation Code of Practice (MEW/R-1, 1997).  
JPC has a lighting load of around 980 kW. 
 
Total connected load of A/C and lighting in JPC is 5111 
kW.  And the percentage share of chillers, CPADA, air 
distribution and the lighting system based on their 
connected load is 37, 22, 21 and 19%, respectively as 
shown in Fig. 2. 
 
 
Figure 2.     Major consumers of power in JPC 
 
 
APPROACH AND METHODOLOGY 
Development of the Smart Operation Strategies was 
based on modifying the current practices of operating 
A/C system and other facilities in the governmental 
and institutional buildings to minimize their power 
demand during the national peak power demand period. 
Baseline performance was established before 
implementing the smart operation strategies.  The 
smart operation strategies were developed and 
finalized in consultation with the facility manager.  
Methodology used for peak power reduction included 
Pre-Closing Treatment (PCT) for A/C system, Time-
of-Day Control (TDC) for A/C and lighting systems, 
and reduction of excessive lighting by de-lamping.  
 
PCT for A/C System and TDC for A/C and Lighting 
Systems 
A common practice in Kuwait is to operate A/C 
systems with a fixed comfort temperature and 
continuous operation of various cooling distribution 
systems such as pumps and fans, in spite of the fact 
that most of the governmental and institutional 
buildings operate between 07:00 and 14:00 h, five 
days a week.  Although, the operation of the lighting 
system is somewhat controlled.  Operation of the A/C 
Chillers 
 37% 
Lighting System
18%
Air Distribution System
23%
Cooling Production and 
Distribution Auxiliaries 
22% 
ESL-IC-10-10-16
Proceedings of the Tenth International Conference for Enhanced Building Operations, Kuwait, October 26-28, 2010
  
system in relation to the building occupancy, termed as 
TDC is an excellent option to save a large amount of 
energy without adversely affecting the quality of comfort 
during the occupancy period.  Likewise, availing the 
stored cooling in the building’s thermal mass, satisfactory 
comfort conditions may be maintained between 13:00 
and 14:00 h with less than required cooling production.  
This scheme defined as PCT, if applied in such buildings 
by limiting the cooling production at 13:00 h can help to 
achieve a 2% reduction in national power demand 
between 13:00 and 14:00 h.  . 
  
PCT was the first to be implemented between 13:00 and 
14:00 h, when the building was still occupied.  It was 
observed that many areas in the building were practically 
empty after 13:00 h.  As a result, PCT and TDC were 
applied together for these areas.  These areas were fed by 
as many as 52 AHUs.  The total connected load of the 
supply air and return air fans of these AHUs was around 
400 kW.  Also, the TDC for the lighting was 
implemented as well in some selected areas after 13:00 h.  
Simultaneously, the operation of the cooling production 
and cooling distribution system was optimized by 
switching off one of the two chillers along with their 
auxiliaries such as the chilled water pumps, condenser 
water pumps and the fans of the cooling towers.  Full 
details of the equipment in operation before and after the 
implementation are given in Table 2.  During the PCT 
and TDC implementation, comfort levels were monitored 
using 10 portable sensors, HOBO model U12-012 in 
different part of the building. 
 
Kuwait has many buildings with very high peak 
power demand, PCT followed by TDC for A/C and 
lighting equipment can be effective tools to reduce 
national peak power demand by 4% MEW, 2007).  
These two schemes could freeze the national peak 
power at the level of 13:00 h.  However, these 
measures have to be implemented with utmost care to 
provide thermal and visual comfort and to ensure that 
the temperature rise is acceptable during the PCT 
period and optimum pre-cooling is provided to 
compensate for thermal build up during the TDC 
period. 
 
De-lamping 
De-lamping refers to removing the extra lights from 
their fixtures.  This is an excellent way to rectify the 
over sizing of the lighting equipment.  Usually this is 
a costless procedure and can be undertaken during the 
time of maintenance.  In areas where light switches 
control more than one fixture and where the light 
levels exceed the recommended values, de-lamping is 
the most suitable remedy.  To correctly reform the 
over utilization of lights by de-lamping, site 
measurement data for light levels for different tasks 
areas are collected and lamps in the areas where the 
illumination levels exceed the recommended ones are 
removed.  Device used to measure the light levels is 
called lux meter.  It is recommended to remove the 
ballasts along with the lamps, since ballasts do 
consume energy.  De-lamping was implemented in 
the corridors and lobbies, while the offices were 
excluded.  Lux levels in the corridors were reduced 
from 385 to 220 (Fig. 3), while in the lobbies they 
were reduced from 465 to 235.  The recommended 
illumination levels for corridors and lobbies are 100 
and 150 lux, respectively. 
 
Table 2. A/C Equipment in Operation Before and 
After Implementation of PCT and TDC 
Equipment Before After 
Chillers 2 1 
Chilled water pumps 3 1 
Condenser water pumps 2 1 
Cooling tower fans 3 (1 H, 2L) 3 L 
FCU chilled water pump 1 1 
Air-handling units 
Supply air fans 
Return air fans 
98 
196 
46 
92 
Fan coil  units 900 900 
H=High speed; L=Low speed 
 
 
  
(a)   (b) 
Figure 3.    A corridor (a) before (b) after de-lamping 
 
RESULTS AND DISCUSSION 
The peak load of JPC was 3700 kW.  Direct savings of 
389 kW were achieved between 13:00 and 22:00 h by 
closing supply and return air fans of 52AHUs.  Also, an 
additional saving of 550 kW during the same period was 
achieved by closing the two of the three chillers and their 
ESL-IC-10-10-16
Proceedings of the Tenth International Conference for Enhanced Building Operations, Kuwait, October 26-28, 2010
  
auxiliaries. Furthermore De-lamping achieved an all time 
saving of 14 kW and an additional savings of 23 kW 
through TDC of lighting after 14:00 h. In conclusion 
project achieved an overall reduction in power demand of 
around 20% between 13:00 to 1700 h and reduction 
ranging from 7% to 15% between 17:00 to 20:00 h as 
shown in Fig. 4. 
0
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a
v
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 %
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o
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Time, h
Before Implementation
After Implementation
savings
 
Figure 4.    Power demand reduction in JPC during  
     PCT and TDC implementation 
 
The temperature build up during the PCT 
implementation between 13:00 and 14:00 h of less than 
2oC as shown in Fig. 5 was not high enough to adversely 
affect the occupants’ comfort level.  Furthermore, 
considering that unlike the JPC, most buildings in 
Kuwait have more energy efficient envelop with 
insulated walls and roof and high quality double glazing 
(Al-Mulla et al, 2008), the temperature build up in such 
buildings is going to be significantly lower.  Thus, 
implementation of PCT in the governmental and 
institutional buildings an hour before their occupancy 
period is safely recommended as a demand side 
management to reduce the national peak power demand. 
 
CONCLUSIONS AND RECOMENDATIIONS 
1. PCT, one hour prior to closing hour of an office 
building is found to have acceptable 
temperature build up of less than 2oC.  
2. TDC is a simple and effective strategy for 
minimizing power demand of A/C and lighting 
systems after the working hours. Available 
building management systems in most of the 
buildings are sufficient for TDC 
implementation. 
3. PCT for A/C system and TDC for A/C and 
lighting systems should be applied to all the 
government buildings in Kuwait. These 
measures will not only limit the national peak 
power demand at the 13:00 h level, they will 
reduce the electricity consumption as well. 
4. De-lamping, should be implemented wherever 
it  is applicable. This is necessary to ensure 
energy efficiency and visual comfort. 
 
10
12
14
16
18
20
22
24
26
28
1 2 3 4 5 6 7 8 9 10
Locations
T
em
pe
ra
tu
re
 ( 
o C
)
 
Figure 5.    Space temperature rise in JPC during 
 PCT implementation between 13:00 and 14:00 h 
  
 
REFERENCES 
1. Al-Mulla, A. , G.P. Maheshwari, D. Al-Nakib, 
A. ElSherbini, F. Alghimlas, H. Al-Taqi, Y. Al-
Hadban, H. Ishaqali, R. Alasseri,  A. Al-
Awadhi and A. Al-Farhan 2008.  Smart 
Operation Of Air-Conditioning And Lighting 
Systems In Government Buildings For Peak 
Power Reduction, Final Report, KISR Report 
9320, Kuwait. 
2. MEW/R-1. 1997. Regulations for electrical 
installations. Fourth Edition. Ministry of 
Electricity and Water, Kuwait.  
3. MEW. 2007, Statistical data book - Electricity 
and Water, Ministry of Electricity and Water, 
Kuwait. 
 
 
 
 
ESL-IC-10-10-16
Proceedings of the Tenth International Conference for Enhanced Building Operations, Kuwait, October 26-28, 2010


Smart Operations of Air-Conditioning and Lighting Systems in a Government Buildings for Peak Power Reduction

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Smart Operations of Air-Conditioning and Lighting Systems in a Government Buildings for Peak Power Reduction

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