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Effective Energy Utilization in the proposed indoor sport hall

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 EFFECTIVE ENERGY UTILIZATION IN THE PROPOSED INDOOR SPORT

                                           HALL



ABSTRACT

        Modern buildings evolved from the rudimentary concept of shelter from the

elements of climate. Effective climate control is therefore central to the suitability of any

building. This study examines the magnitude of the influence of design variables that

may mitigate discomfort in the proposed Indoor Sport Hall. It will asses the additional

cost that may incure in running the proposed building vis-à-vis the worsening global

energy crises and in particular, the like in energy cost in Nigeria.


        Representative samples of buildings with different architectural design

characteristics and construction materials across the three broad geographical regions of

Nigeria are assessed and compared, based on effective energy conservation. Also, related

building occupants Representative samples of buildings with different architectural

design characteristics and construction materials across the three broad geographical

regions of Nigeria are assessed and compared based on effective energy conservation.

Also, related building occupants across the three basic income strata are interviewed on

the comfort level of their respective types of buildings and the energy cost of running

them.


        The study reveals that architectural design and construction materials influence

building micro-climate remarkably, thereby, influencing the cost of requisite energy for
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micro-climate control. Recommendations on possible means of achieving efficient energy

utilization in buildings for improved quality of life are stated.


INTRODUCTION

       A building is a shelter from rain, sun and wind. Good architecture merges this

with proper proportions and fine details (Ware, 1900). Historically, architectural forms

have largely resulted from man’s struggle with adverse climate conditions; however,

today’s technology control of micro-climate has led to the disappearance of distinct

regional types of architecture (Kemper, 1979). These clearly show that climate is central

to building design and construction and can be regarded as the most basic and

fundamental factor, while artificial energy input is highly essential in mitigating its

undesirable effects.


       Climate can be defined as the prevailing atmosphere/weather conditions steadily

occurring over an expanse of land, usually very large (Udo, 1970). The major indices of

climate are temperature rainfall, humidity and air movement (fig A). Substantial control

of micro-climate can be achieved through the proper manipulation of elements like

thermal mass, shading devices, building orientation type and size of fenestration and the

choice of materials (fig B). However, for the achievement of the ‘perfect’ micro-climate,

mechanical gadgets/equipment like air-conditioners, heaters and fans are required. This

equipment requires artificial energy input like electricity and/or fuel-oil. It is necessary to

keep this energy requirement to the minimum level, particularly in Nigeria where

electricity supply is crassly erratic and the cost of fuel-oil increases annually.
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       Markus and Morris (1980) express that the building is not an inert mass of stone,

concrete and/or iron; it is almost a living body, with its own blood circulation and

nervous systems. In its walls, which appear so immobile, circulate gasses, and

fluids/liquids, through flues, pipes and wires which are the arteries and veins which

conduct heat, cold and fresh air with energy supplies through natural and artificial means.

The combination of the building carcass with efficient energy system is therefore

fundamental in the production and well being of any building and perhaps the well being

of its owner(s).


PROBLEM STATEMENT

       The characteristics of traditional architectural design in Nigeria were determined

by the natural conditions of the given area, most of all by the climate and available

building materials (Dmochowski, 1990) and houses were tailored to the needs of the

people (Denyer, 1978), thereby requiring only minimal artificial energy input. On the

contrary, building design and construction in contemporary times in Nigeria as evident in

the numerous buildings around are known for superfluous use of foreign, materials and

alien design concept in the craze for flamboyant aesthetics and grandeur, at the expense

of functionality and cost efficiency.


       Thomas (1979) avers that the history of buildings in Nigeria can be seen to

encourage energy conversation, primarily due to a dearth of energy and technological

disadvantage. At the end of the colonial era, traditional buildings had started giving way

to European building patterns which sought to conserve heat and limit the entrance of

cool air contrary to the reality in Nigeria where heat ought to be dissipated through
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constant flow of sufficient air. These buildings create uncomfortable micro-climate which

requires huge energy input for cooling and lighting, consuming large sums of money in

energy cost. Unfortunately, according to Knight (1979), all energy used on creating

micro-climate in buildings is wasted. It disappears through windows and building fabric,

compared to the energy used in manufactures which produces tangible end products.


       The gravity of the situation is underscored by Clarson (1979) stating that the

average energy costs of running our buildings today represent 5% of our personal energy

consumption and about 3% of industrial turnover. When translated into currency, this will

amount to several millions of naira per annum. Makus and Morris (1980) paint a grimmer

picture stating that house lighting, fuel and power expenditure represent between 3% ( for

the wealthiest) and 10% (for the poorest) of family income in Britain.


       The energy problems of developing countries and the deepening poverty in most

urban centres which are now evolving, not in the developed world but in developing

countries without and commensurate economic or developmental growth (Mabogunje,

2001)require close attention to the issue of energy conservation in buildings.


JUSTIFICATION

       Table 1 buttresses these facts as it shows that electricity consumption in Nigeria

between 1994 and 1998 steadily declined. Unfortunately, this was not due to a fall in

demand; rather, it was due to the declining supply occasioned by the gross inefficiency of

the Power Holding Corporation of Nigeria (PHCN). Electricity supply can therefore be

said to be available to an insignificant proportion of Nigeria.
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       There is need for man to live in an environment that is conducive for living,

working, worshiping, and recreation and has necessary aesthetic qualities.


       To achieve such a balanced environment, provisions must be made for effective

Energy Utilization in the building.


Table 1:       Electricity Consumption in Nigeria KWH

               1994            1995             1996         1997            1998
Industrial     2,042,100       2,037,211        2,061,440    1,897,360       1,854,613
Commercial     2,519,176       2,448,877        2,452,758    2,424,061       2,307,855
Residential    5,032,574       4,949,818,       4,527,563    4,521,762       4,358,751
Total          9,593,850       9,435,906        9,041,761    8,843,183       8,521,219


AIMS AND OBJECTIVES

       The aims and objectives of this paper is to give an alternative to artificial energy

that has proved of not effective in most of the buildings of which this research has been

conducted in Lagos, Abuja and Kano. The decline in electricity supply resuscitates the

need to develop buildings which will conserve energy naturally and reduce the need for

artificial energy input to the minimum.


SCOPE AND LIMITATION ON HUMAN COMFORT

       Kemper (1979) states that a healthy human body maintains a constant inner body

temperature of around 37oC/98oF. Although the body can be trained to maintain its

temperature in extreme climate conditions, most people have discomfort at temperature

below 15.5oC/60oF and above 29.5oC/85oF. High humidity adds more discomfort in hot

weather as well as in the cold. Natural sensitivity to temperature and humidity varies

slightly from person to person. People’s comfort zones also vary with the different
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climate zones on the planet. In temperatures below the comfort zone, people require

warmth/heating while they require cooling at temperatures above it. Relative humidity

above 60% is considered too high and requires sufficient air movement, either naturally

or mechanically.


       Table 2 shows a comparative assessment of the climate conditions in the three

major geographical zones of Nigeria in relation to the maximum tolerable condition.


Table 2:       Comparative Assessment of Climate Conditions in Nigeria

Town                  Maximum          Threshold         Maximum            Threshold
                      Temp (oC)        Temp (oC)       R. Humidity %       R. Humidity
Lagos                   30.7             29.5               98                 60
Lokoja                  32.3             29.5               70                 60
Kano                    33.1             29.5               60                 60

       Table 2 clearly reveals that natural climate conditions in Nigeria do not meet

suitable human comfort requirement. It is therefore necessary to control the

micro-climate in buildings through natural and mechanical means to achieve comfort.

Table 4 represent a broad categorization of conditions under which mechanical cooling

may be required to achieve comfort in buildings.


Table 3:       Conditions under which Mechanical Cooling may be necessary to Achieve
               Comfort
Form of Cooling               Conditions Temperature         Relative Humidity %

Evaporative Cooling                     35 – 37                       Below 35%
                                       *37 – 40                       Below 25%

Air Cooling                             35 – 37.5                       0 – 60%
                                       *37.5 – 40                      20 – 50%
                                       *40 – 42.5                       0 – 45%
                                       *42.5 – 45                       0 – 40%
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Air Cooling       and     de-            31 – 33                        above 85%
humidification                          *33 – 35                        above 70%
                                        *35 – 37.5                      above 60%
                                        *37.5 – 40                      above 50%
                                        *40 - 45                        above 40%
* Indicates excessive discomfort

Source: Housing Climate and Comfort (Evans, 1980)

EXPECTED CONTRIBUTION TO KNOWLEDGE

Thomas (1979) opines that traditional building pattern and planning in Nigeria

complements conservation due to the limited energy resources. In rural areas, building

shapes, forms and functions are still very traditional. Buildings are still being constructed

with predominantly clay mud, which cools the building naturally in the hot season and

warms it in the cold season that is, allow the building fabric to ‘breathe’. The deep roof

overhangs of traditional/pre-colonial buildings provide adequate shade for the building

envelope and internal spaces, thereby requiring minimum artificial energy input (fig).


       At the advent of the colonial masters, buildings became refined, though; basic

respect for functionality and energy    conservation    was    maintained.   The    colonial

buildings adopted traditional materials in refined form. Wood was especially used

extensively for floors, roofs stairs, and windows, and so on in contrast to contemporary

preference for concrete, steel and glass. Energy conservation was paramount as

residential quarters were built with two kitchens, one deriving its energy requirements

from wood, the other from the limited electrical source generated then from coal. The

rooms were well ventilated by providing large areas of fenestration for cross ventilation

with moveable wooden louvers which were entire storey high. These also served other

roles of admitting high proportion of natural lighting, thereby, further reducing the
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artificial energy requirement for lighting. Thomas (1979) adds that statutory planning

permission was based on these requirements, unlike today.


       The end of colonial rule, inadvertently coincided with the discovery of oil in

Nigeria and the attendant haste for development in the oil boom era brought about the

construction of many buildings rapidly. Post-colonial buildings were characterized by

excessive use of foreign building materials and the designs necessitated very high energy

requirements for micro-climate control and lighting. In the quest for modernization and

status-symbol, many of the contemporary buildings can not function at all, without

artificial energy. Such buildings include among others: the National Theatre, Lagos, and

Federal Secretariat Complex, Abuja and the Nicon-Hilton Hotel, Abuja and many others.

These buildings which were produced in defiant disregard for the original statutory

standards and regulations governing natural ventilation and lighting unfortunately got the

approval of the respective planning authorities.


ENERGY CONSERVATION AND CLIMATE

       Markus and Mosrris (1980) state that the energy consumption in buildings is

related to the natural energy system, that is, the climate in which buildings are located, as

well as to the properties of the shelter itself. Even the dispersion of wastes and pollution

in and around buildings is a climate dependent phenomenon. Kemper (1979) states that

building design has two basic considerations: One is oriented towards human purpose and

other towards the physical environment, and architects and planners can strongly

influence energy usage through their designs.
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       For efficient energy utilization in buildings, therefore, good understanding of

climate and its features is a sine-qua-non for ensuring that it is well manipulated to

advantage while concomitantly raising comfort and health standards.


       Hornby (1998) defines climate as the regular pattern of weather conditions, that is

temperature, humidity and air movement of a particular area. Udo (1970) defines it as the

prevailing atmosphere/weather conditions steadily occurring over an expanse of land,

usually very large. The earth is divided into different climatic zones, usually as a direct

function of location on the globe, that is, latitude, attitude above the sea level, distance

from the oceans and the condition of the particular ocean, and they are usually

distinguished by varying vegetation forms.


       Micro-climate refers to peculiar conditions of general climate over a locality, a

relatively smaller portion of the climate zone (Kemper, 1979). In addition to air

movement variations created by urban forms, factors of elevation, topography, water

bodies (natural and manmade) create peculiar micro-climate. Conditions within building

enclosures can also be referred to as micro-climate of interior spaces.


Table 4:       Major Climate Zones and the Respective Features

           Zone                      Location             Temperature          Rainfall
1.         Warm Humid/Tropical       15oN – 15oS high            Fairly            High
2.         Sub-Tropical              25o - 45oN and              High              High
                                     SWest East Coast
3.         Hot Dry (Desert)          15o - 30o N               Very high         Very low
4.         Maritime Desert           15o - 30o N                 High              Low
Source: Geographical Regions of Nigeria (Udo, 1970)
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The climate type in Nigeria is categorized as Tropical Warm and Humid (Udo, 1970),

characterized by high temperature and very high humidity – the two major causes of

discomfort in the tropics. Table 2 presents climatic data for the three broad geographical

regions of Nigeria, represented by a city each.


Table 5:        Meteorological Data for the Three Geographical Zones of Nigeria

Elements                       Lagos                Lokoja                  Kano
                          Southern Zone           Central Zone         Northern Zone
Rainfall (cm)                   182                   122                    83.8
Temperature
(oC) Max                        30.7                  32.3                   33.1
      Min                       21.8                  22.2                   19.2
Relative Humidity
% Max                            98                    70                     60
  Min                            73                    41                     32
Source: Meteorological Centre, Lagos (1990)


DATA ANALYSIS AND DISCUSSION

Table 6:               Level of Comfort in Buildings Constructed with Different
                       Materials, without the use of Mechanical Equipment
 Construction
  Materials                                    Comfort level
                      Morning            Afternoon         Night               Total
Mud                       2                  1                2                    5
Brick                     2                  1                1                    4
Sandcrete block           1                  0                1                    2
Wood                      2                  0                1                    3
Glass                     0                  0                0                    0
Source: Authors’ Fieldwork
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Key

2      =       Very Comfortable

1      =       Fairly Comfortable

0      =       Uncomfortable


       Table 6 reveals that construction materials influence the level of comfort in

buildings substantially. Mud wall is presented here as the most favourable for suitable

micro-climate in buildings. This could be due to the fact that it absorbs heat very slowly

and ‘breath’, dissipating acquired heat into the cold night, thereby preserving stable

temperature within building enclose. Sandcrete block wall which is the most extensively

used in Nigeria’s urban areas today is presented here as performing below average in

terms of providing comfortable micro-climate. Glass is shown to be the worst materials

for walls in the Nigeria climate as it traps all the heat absorbed in the building enclosure,

creating a local ‘green-house effect’.


       Since heat is the major cause of discomfort in the Nigeria climate, a comparative

analysis of the room temperature of buildings of various design characteristics taken at

12.00 noon was conducted to assess the impact of design on the energy requirement of

buildings for comfortable micro-climate.


Table 7:       Average Room Temperature of Different Design Forms

No    Room Characteristics (4m x 4m)               Av. Temp(oC)           Av. Temp (oC)
                                                   Southern Nig.           Northern Nig.
1.    Deep roof overhang providing shade
      for external walls
(a)   With Cross ventilation Storey – high
                                            12


      (2.4m) windows                                  27.5                   33.3
(b)   With Cross Ventilation: 1.2m high
      windows                                         30.0                   32.1
(c)   No cross ventilation: window on
      only one side                                   31.2                   34.7
2     Minimum roof projection, exposing
      external walls to direct sun ray
(a)   With cross ventilation: storey – high
      (2.4m) window                                   29.8                   34.8
(b)   With cross ventilation: 1.2m high
      windows                                         30.9                   33.0
(c)   No cross ventilation: window on
      only one side                                   32.0                   35.6
Source: Authors’ Fieldwork


       Table 7 reveals that building with deep roof overhang have general lower room

temperature which varies according to other design characteristics. It can be seen that

extensive roof projection is effective in reducing discomfort in buildings both in the

Southern and Northern parts of the country, thereby, reducing the amount of artificial

energy required for cooling.


       It is also observed that the provision of cross-ventilation substantially reduces

room temperature across the two extreme geographic regions of Nigeria. Adequate

provision of cross-ventilation can therefore be adopted to achieve comfortable

micro-climate thereby saving energy cost.


       The adoption of storey-high windows is observed to be very effective in reducing

room temperature in the southern zone of the country. Actually, room temperature of
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only 27.5o C (which is comfortable for a normal healthy person, without mechanical

cooling) was recorded compared to 30.0o C for a room of the same size with the prevalent

1.3m high window. However, the same cannot be said of the Northern zone. This may be

attributed to the very hot air in the environment, which could raise the room temperature

rather than reduce it, when the inflow is high.


       By this study, it is evident that the manipulation of design characteristics like

shading device, choice of materials, type and size of openings and thermal mass can be

skillfully manipulated to create comfortable micro-climate in buildings, thereby ensuring

efficient energy utilization in buildings.


THE EXPECTED RESULT

       The cost of energy consumed in creating suitable micro-climate in buildings in

Nigeria is too high, being a developing country with gross domestic product (GDP)

which ranks among the world’s poorest (UNDP, 2002).


       The situation must therefore be immediately redressed. The following are

recommendations on the means to achieve this:

       1.      Proper orientation of buildings to reduce the impact of unfovourable

               weather conditions

       2.      Efficient building shape and adequate shading of building envelope

       3.      Adequate and efficient fenestration for proper air movement

       4.      Use of climate-responsive and locally available building materials.

       5.      Creation of conducive micro-climate in the immediate environment of

               buildings through the provision of outdoor water bodies like pools, pond
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            and fountains and extensive vegetation cover to reduce heat and glare in

            the immediate environment.


REFERENCES

1.   Agagu, O. (2002). Developments in the Electric Power Sector (May 199 – April

                       2002). Paper delivered at the 2002 Media Summit on Power,

                       Abuja

2.   Kemper, A. (1979). Architectural Handbook. McGraw Hill, New York

3.   Lukeman, R. (2002) Moves to end gas flaring. The Guardian, Lagos, 6 Aug, Pg.

4.   Clarson, D. (1979). Financial aspects in Ove Arup Partnership (Eds.) Building

                        Design for Energy Economy. The Construction Press,

                        London.

5.   The Environ-scope: A Multidisciplinary Journal Vol. No. 1 PP. 37 – 43



By          OLAYEMI Ajibola Oladpo (M.Tech. 1)
                 ARC/01/0454

				
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