Future design in an energy efficient building as an

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					V      Future design in an energy efficient building as an identity of a Malaysian tropical
                  architecture with emphasis on photovoltaic technology and
                             passive solar building design elements

                             Abdul Malik Abdul Rahman 1 and Mohd. Rodzi Ismaif

    1. Deputy Director                                2. Lecturer
       Center for Education, Training and Research       School of Housing, Building & Planning    J{ P; .f>
       in Renewable Energy & Energy Efficiency           Universiti Sains Malaysia
       (CETREE) Suite 125, Kompleks Eureka,              11800, Minden, Pulau Pinang
       Universiti Sains Malaysia,                        rodzi@usm.my
       11800, Minden, Pulau Pinang.
       malik@usm.my


Abstract

There has been indicators that global warming is now approaching towards dangerous levels. The world over is
now into sustainable development and as far as energy is concerned many countries are looking towards
Renewable Energy as alternatives and the most promising is the energy from the sun, i.e. the solar electricity.
Due to the awareness and education there is an increase demand on photovoltaic technology and subsequently
an increase in cost as well. High cost dampens demand and the eventual lack of demand prevents further
research into lowering the cost of the system thus setting a vicious circle. Therefore government intervention is
necessary to kickstart this promising clean fuel by introducing the necessary initiatives to bring down the cost of
PV technology because the advantages of using sun power are enormous. This paper suggest solutions by
stipulating four strategies to overcome high cost ofsolar installation by passive design combining with energy
efficient active systems manage by a favourable and passionate mindset and employing the solar technology.
Though the PV technology is pretty straightforward, solution incorporating passive solar design elements to a
building design needs an Architect's creativity. There is a dire need for research into these design elements to
make an effective reduction in indoor air temperature and also cooling the surrounding outdoor without using
much energy.

Keywords: passive solar design elements, energy efficient, photovoltaic technology, building design,
          solar electricity




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1. Introduction

         In tropical countries, as dependence on cooling systems and air-conditioning increase in
pace due to economic growth, growing concern over the future global environment problems and
a possible drain on energy resources require to place importance on development of the passive
design cooling technology as well as incorporating the renewable energy into the building fabric.
         For many years Malaysia has been blessed with oil and natural gas both obtained from
burning of fossil fuels. As energy cost continue to rise and fossil fuels depleting, maintaining a
balanced socio-economic fabric is getting terribly expensive for the Government. Thus renewable
energy now become the fifth fuel adding to the energy policy of the existing four fuel, namely,
oil, gas, electricity and hydro. Renewable Energy (RE) has been set aside by as much as 5% of
Malaysian energy supply.
          While RE initiatives are beginning to gain some inroads into the market, the concept and
initiatives of Energy Efficiency (EE) are to run parallel to it. EE is not the same as energy
savings. While the later connotes a cutting down of activities, thereby a drop in living standards,
the former encourages the opposite and to use energy efficiently, thus maintaining
competitiveness internationally. The Fifth Fuel Policy is silent on how much from the 5% is
apportioned to solar energy, biomass, wind, etc. It is up to the industry players to convince the
government which RE initiatives in Malaysia to be economically viable to gain competitiveness
and get the support of the government. Buildings in Malaysia has been noted to consume almost a
third of the overall energy consumption and therefore warrant some attention.
         Other alternative renewable energy have little infuence in building design. Industry
players are more interested in researching and manufacturing in heavy machineries that consume
huge amount of energy. For example energy from hydrogen is very promising but for the moment
they are heavily researched into for car technology. Malaysia learned a lot from the scientific
development from overseas. Research would take not only a long time but also a hug e amount of
the country's economic budget. Along with striving for Malaysian Nobel Laureates, certain well-
tested technologies can be adopted and adapted. To start anew would be unwise. Buildings that
are designed to use solar energy need to consider the storage of hydrogen later in the future.
          Wind is unreliable in Malaysia as the characteristics of wind is that it is erratic,
unpredictable in air velocities and multi-direction. It cannot be relied fully to influence the design
of buildings. Biomass need a lot of space and for urban design, space is not that generous. What
Malaysia has is continuous supply of sunlight and the energy source is totally free. With
photovoltaic technology sunlight can be converted into electricity. The photovoltaic (PV) system
is silent in operation, maintenance free and very friendly to the enviroment because no toxic gases
are released. Architects and others from the building industry must take note that eventually a
benchmark on energy consumption by a building will have to be met before building approval
can be given to proceed with construction. At the moment any industry that consumes 6 million
kWh of energy is mandatorily required to employ an energy manager. The Ministry of Energy,
Water and Communication Building at Putrajaya has given itself a standard of 135kWh/m2/yr as
the benchmark to achieve and it has done so. The Malaysian Energy Center Building has gone
even lower of 120kWh.m2/yr. Future buildings may eventually take the same approach set by
authorities. For the moment it is by persuasion. This paper aims to show presently that solar
energy is a promising alternative for future energy demands in buildings. Though the Malaysian
consumer market can be flooded with all kinds of energy saving appliances, equipment, and
machineries over time, the design of buildings do not take the same approach as design is site
specific. One has to do a stie analysis by studying the sun path, the prevailing wind (if any), the
surrounding terrain and make use of the natural endowment to help reduce heat buildup onto the
building fabric first before ever considering to use any energy saving mechanical aids. By doing
so it further will reduce energy consumption. In Malaysia about 70% of energy consumption is



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for cooling the environment. When the price is reasonable, photovoltaic system seemed to be the
answer for Malaysia.

2. Photovoltiac technology in building design

         The world over is now into sustainable development and therefore among other things,
the demand for PV technology has risen thereby pushing the prices which makes it an expensive
technology to champion. Research and efforts are geared to find ways to reduce PV prices. One
of the ways is to increase demand. This can be done by creating awareness of the need for PV
technology which can save the world from climate change thence global warming. But the
common public needs more convincing and must be encourage with examples closer to home
rather than overseas.
         The recent introduction of the Malaysian Building Integrated Photovoltaic (MBIPV)
project or campaign will provide a great opportunity to address this issue holistically.
Government can help create an environment where consumers and industry can drive the PV
market. Apart from appropriate policies as incentives and legislations to ease the dilemma, RE
requires a conducive and supportive financing system to allow private developers to apply them.
This would help encourage property developers and the building industry to incorporate the PV
technology into their developments. Developers would not feel hesitant to incorporate the design
and construction of sustainable buildings.
         PV technology is without doubt the best form of renewable energy to be used in buildings
only if the price for the whole system is affordable to the ordinary public. While waiting for the
price of PV technology to be affordable there are other options which can be initiated almost
immediately firstly by persuasion, later by mandatory regulations and expedited by EE products
in the market, before installing solar electricity. Malaysia is still far behind in the PV technology
(15 years behind) as compared to Germany who is the market leader. A national program (Figure
1) assisted and funded by the United Nations Development Program (UNDP) is under way to
change the mindset of the Malaysian population into accepting the idea of solar electricity. It is
hoped that with increase in demand, prices would eventually drop.
         The campaign starts off with "SURIA 1000" ("suria" means solar) and the figure 1000 is
to represent that the stakeholders aim for 1000 roofs to be fixed with solar panels by 2010. And it
specifies the system to be integrated into the building design as the name implies - Building
Integrated Photovoltaic (BIPV). This means that no reftrofitting is allowed. Those who opted to
be in this program will have their cost of installing the PV technology be subsidized (Figure 1).
         It is aimed at successful completion of this long term program to be in 2030. It was also
predicted that the whole world supply of petroleum would already be diminished by the year
2040. There may be some reserves here and there but not economically viable to access to it.
         There are four strategies available for those in the building industry to play their part in
helping with curbing the growing global warming. The main players are the Architects, the M&E
Engineers and the clients (building owners and/or developers) themselves. Consumers too must
play their part in being rational in energy issues and must be made aware of the world situation.
Their cooperation collectively will be translated into action to whatever extent possible. Any
small efforts, collectively, would make a great impact in savings over a period.




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                 Figure 1: A 25-year program for photovoltaic technology in Malaysia


3. The Four Strategies for a Paradigm Shift

         The four strategies can be used for Energy Auditing of existing buildings and also can be
used as a guidelines for designing of new buildings. A Mechanical and Electrical Engineer would
use this method but with more emphasis on the appliances and systems whereas for the Architects
the design approach and concept would be the starting point. The strategies are firstly, the passive
solar design building elements, the second would be the active systems such as the mechanical
and electrical systems, the third is more towards attitude building, changing the mindsets, and
monitoring and finally the use of available renewable energy.
         The first strategy is to incorporate as many as possible the appropriate passive solar
design elements into the building design. In Malaysia the criteria for an ideal comfortable thermal
environment is to have an ample air movement and a cool surrounding. Architects should strive to
incorporate design elements to create as close as possible to the ideal condition outdoors and
indoors. The ideal conditions for Malaysian thermal comfort has been found to be between 24°C
to 28°C. The rule of thumb is to strictly avoid as much as possible from letting the sun rays into
the interior of buildings. Sun shine into the building would heat up the highly densed floor which
absorbs the heat to be stored in whatever material the floor is made of. Depending on the density
of the floor and upon complete absorption, the already heat-saturated floor will then reradiate
excess heat into the air above it. For thicker floors the heat will be stored until night time and
when the air temperature above is lower than the temperature of the material a process of heat
transfer from the material to the air will occur thus warming up the air above and surrounding the
room. The situation would be made a lot worse if the heat passes through conventional window
panes into the interior with no ventilation. The smaller wave radiation could not escape and
therefore trapped to raise the indoor temperature.This can be experienced in cars locked up under
the sun and the interior heat can be very intense. This thermal behaviour does not only happen on



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floors alone but also on walls and other hard objects within the interior. Timber materials absorbs
heat readily and releases heat quickly. Exposed concrete to the sun too is bad for the immediate
indoor environment.
         The East-West orientation rule is the first approach in layout planning for it reduces
encroachment of sunlight into the interior by exposing a smaller wall area to the sun. By doing so
one can open up to maximise the daylight factor to the interior thus savings instead of having to
install many light bulbs to obtain the same ligthing effect. There are many ways to use
sunshadings and it is up to the Architect's ingenuity to use them aesthetically. Other passive
design elements are the use of creepers on the walls facing the sun path, roof and wall spray
mists, landscaping, inducing stack effect, and many others.
         The passive design approach may have a slight increase in construction cost but it would
not incur any running cost. It may not give the exact thermal environment that is conducive to
comfort but it will definitely reduce heat gain. A reduction of thermal build up by passive means
is a complex effort in a tropical climate especially when the average air temperature is about 33
degrees centigrade and very high relative humidity of about 80%, and though some reduction of
high temperatures can be obtained it cannot be relied upon totally without the aid of mechanical
means to generate air movement. And we also need to depend on the second strategy and that is
the contribution from the active systems.
         Simply put, active systems are more towards the EE appliances, products and machines.
These EE machines produce more with less energy. The refrigerators in Malaysia is one of the
top runner programs by the Malaysian Government to introduce EE refrigerators. In a domestic
house, refrigerator runs for twenty-four hours and thus consume a lot of energy. The labeling
system was launched recently to announce to the Malaysian public as to the existence of the EE
refrigerators in the market. A five star is the most efficient but a bit costly and a one star reflects
inexpensive but not so efficient in energy consumption. Air-conditioning is another household
good to be researched into as cooling the building by air conditioning is a wasteful effort. A great
difference in indoor air temperature and outdoor temperature would consume a lot of energy. By
increasing the indoor air-conditioning to an acquired comfort temperature of about 25 degrees
centigrade would vastly cut d'own electricity bill.
         Using less electricity but not reducing our standard of living is considered as the best
practice. Producing more with less is the norm that should be nurtured. Reducing electricity bill
means that less fossil fuel is used up. And when less fossil fuel is tapped the environment is then
well preserved and conserved. The rate of converting the natural resources into fuel would be
slowed down and also reduce the rate of global warming.
         Other equipment that needs to be looked into as EE products are the electrical fans,
toasters, irons, microwaves, electric food warmers, computers, etc. Electric bulbs such as those
produced by Phillips and Osram though a bit costly would give a long lasting product life. Light
Emitting Diodes (LEDs) can last for 11000 hours as compared to ordinary light bulb which lasts
only 3000 hours. Awareness to the public is paramount on the availability of the state of the art
EE household appliances and lighting. Although EE household appliances and lighting
technologies can save the amount of electricity, they still have not been widely adopted. Again
cost has been one of the main barriers but this again can be reduced by the increase in demand.
For the moment the small LED bulb cost RM90.00 as compared to a tungsten bulb which is
highly inefficient which may cost RM7.00. Policies and programs to promote the large-scale
penetration of energy efficient technologies and market transformation are underway but at a
slow pace.
         While that is happening, it would pay for the public to change their paradigm and
inculcate a culture of EE behaviour. This is the third strategy. A good guide can be refered to
from a booklet produced by Energy Commission (EC) in collaboration with the Danish
Cooperation for Environment and Development (DANCED) and the Center for Education,
Training and Research in Renewable Energy & Energy Efficiency (CETREE). An EE mindset


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requires one to be conscious in things sustainability, 'green' environment and conservation. With
that consciousness in mind and with enough passion one behaves in a responsible manner in
everyday life. Some examples of the EE behaviour are not to place the refrigerator by the window
which is exposed to the sun, have ample ventilation around the refrigerator, switch off air-con in
unoccupied rooms, switch off lights or fan when not in the room for a long time. Use the sun to
dry clothes and many others. If possible sweep dust and collect it to a spot before using the
vacuum cleaner to suck it from that spot. Do not just iron one clothing but grouped them and iron
all at a convenient time. There are many more habits to be inculcated to ourselves and also the
minds of our young ones so as a culture is nurtured.
         Implementation of the three strategies mentioned above would greatly reduced the
amount of electricity consumed in a building. A building can not only use energy efficiently but it
also produce more electrical power than required by installing solar electricity. The building can
sell the extra kilowatts back to the Tenaga Nasional Berhad (TNB - National Electricity Board).
The TNB will buy back from the building owners presently O.l7sen per Watt. So installing the
PV system is the fourth strategy. But the initial installation cost for solar electricity is a deterent
for any individual building owner to employ into this approach. Once installed this would then be
the final strategy. At present an average home with only basic requirements of comfort living
would consume at least 3kWp (kilowatt peak) of electricity. A solar panel would come in many
different sizes but the average size determined by easy handling so far has been a 600mm x
1200mm x 30mm in dimension with a power of about 185 Wattslhour (varies with different
manufacturers). A single panel would fetch about RM2900.00.
         From the table we can deduce that for a conventional design with minimum
considerations of the passive solar design elements incorporated in the building design and with
no energy efficient household goods combine with the lackadaisical attitude of the public or
probably unaware of the big picture, the energy consumption would assumed to take a high load
approximated as 5kWp. To counter this as many as 27 solar panels are needed and this is a
deterent due to high cost of installation. And 27 solar panels need a big surface area facing the
direct path ofthe sun. For 100% efficiency they need to be as near horizontal as possible and this
may be a limitation to creativity in the design of roofs. If they are not of an amorphous type of
solar panel (where energy can still be absorped even under shade) there cannot be any obstruction
between the sun and the panels.
         Table 1 also shows that the building cost is estimated as RM750000.00 and an
installation of PV system using 27 solar panels incur a 20.9% added cost to the property. The
Suria 1000 campaign aims at the higher end market to help to promote the use of solar
electricity. This is to gain the public's attention and hopefully it becomes a status household item.
         This is where the Architects must show interest in this energy-form relationship to quest
for an architectural form as a part of manifestation of the energy flows that are inherently present
in any building. What Table 1 is saying is that one should approach with the passive solar design
elements first in designing a building even though the initial building cost is about 10% more
 because the cost for PV system is only 11.4% as compared to the same building design without
passive design elements which incurs a 20.9% on PV system.




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   Table 1: The transformation from conventional building design to energy efficient building

STRATEGIES                                  Conventional              Option            Option
                                            Design                    One               Two
ARCHITECT'S ROLE:
1st Strategy :Passive Solar
              Design Elements               Minimal                   Minimal           Priority
Cooling the Building Fabric:                considertions             considerations    given
Orientation; Roof & Wall Spray              given                     given
Mists; Landscaping; Creepers;
White Paint; Reflective Materials; Etc.
Generating Air Movement:
Orientation; Wind Wingwalls;
Fenestrations; Window Designs;Etc.
              Daylighting

MECHANICAL ENGINEER'S ROLE:
2nd Strategy : Active systems              No                         Purchase of       Purchase of
All types of electrical lighting           considerations             EE products       EE products
Television; Computers                      at all
Air conditioning; Fans
Iron; Kitchen appliances
Refrigerator
Fax machine; Photocopiers; Etc

CLIENT'S ROLE:
3rd Strategy: EE mindset                    Lackadaisical             EE behaviour      EE behaviour
                                            attitude
         TOTAL PV
         CAPACITY (assumed)",l              5kWp                      4kWp              3kWp

4 th Strategy: PV Technology
185W solar panel @ RM2900.00 / panel
Number of panels needed                     27                        22                16
a. Total cost of panels                     RM 78300.00               RM 63800.00       RM 46400.00
b. Estimate cost ofperipherals· 2           RM120000.00               RM 90000.00       RM 60000.00
c. Total Cost ofInstallation                RM198300.00               RM153800.00       RM106400.00
Building price (estimate)                   RM750000.00               RM750000.00       RM825000.00· 3
Total price of property (estimate)          RM948300.00               RM903800.00       RM931400.00
% PV installation cost                      20.9%                     17%               11.4%

• With every strategy taken there would be a drop of 1kWp. No comprehensive study yet to date.
• Peripherals - inverter, cables, electrical equipment, mechanical structure and labour
• Add RM75000.00 a 10% increase in building costfor passive design elements.




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Figure 2 advocate for a design with PV technology consciousness by first designing using
appropriate passive solar design elements and install the solar panels at strategic location so as the
aesthetic values are not compromised. Figure 3 shows a general guide of all the passive design
elements made available in Malaysia that can reduce heat gain on a building fabric and finally
the PV panels are placed on top of the jack roof. Architects are left to their ingenuity and
creativity to make the integration of solar panels aesthetically pleasing to the common people
otherwise rows and rows of stright forward panels in linked houses can have a psychological
impact over a long period. Most Malaysian would prefer to have attachment to organic materials
and a rustic look to their private homes. Rustic effect and PV technology conflicts in this sense as
one is organic and the other manufactured, and may not be successful as a selling point in the idea
and also the property. All the passive design elements must not be applied as any additional
element may not give a significant drop in internal air temperature and therefore may add up
unneccessary building cost. Architects are to study the surrounding site and emphasis its natural
strength and endowment and design accordingly before integrating the roof with solar panels.




Figure 2: (a) A high rise neighbourhood with comprehensive incorporation of passive design
elements (courtesy of Ken Yeang) (b) A building integrated photovoltaic after passive elements
have been considered (in this instance it is the wall with the small surface area faces the sun).

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                         Figure 3: The passive design elements and PV technologv
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4. Passive solar building design elements.

Refering to Table 1 Architect's Role the section on passive solar design elements are the variables that
immediately affect the cooling on the building itself. Option 2 is the direction that should be approached at
in order to reduce the cost ofPV technology and here it is the Architect's intuition and instinct based on the
scientific research and database from Table 2, to concoct a good design where energy consumption is the
major influence in how the building would look like and be acceptable to the general public. Building
materials are constantly being researched into to find the best thermal performance. But no matter what the
materials seem to be, any direct sunlight into the house would defeat the purpose of having a good thermal
performance material. Whatever material used for the building envelope it should be supplemented with
efforts to reduce radiant heat by the design of building such as the shape and orientation, roof shape and
roof pitch, sun-shadings of all sorts, roof and wall sprays, reflective materials including white paint and
insulation materials. Once the building fabric is prevented from heat gain at the same time there must be
efforts to encourage air movement inside the building. Such initiatives are like having wind deflectors,
shape and orient the building shell to maximize exposure to the prevailing wind, open plan, air shafts to
encourage stack effect, double wall and double roof and lots of fenestrations. These are known as passive
solar elements because they do not incur any running cost, but can enhance the aesthetics of the building.
Table 2 shows the design elements that can prevent heat gain to the building fabric and still requires further
research as to the effectiveness of each item. Figure 2 shows the inclusion of all the items from Table 2.
Research findings confirm that having all the items do not necessarily bring down the indoor air
temperature significantly. The Architect must assess the building site first to use as much natural
endowment provided by the site before using selective items from Table 2 to enhance the building
performance.

            Table 2: The passive solar design elements to prevent heat gain to a building fabric

   REDUCE RADIANT HEAT GAIN                       BEFORE                 AFfER           DIFFERENCE

   1.  Orientation
   2.  Roof shape and pitch
   3.  Shape and orientation
   4.  Sunshading
   5.  Creepers                                   36.8C (without)        27.7C (with)              9· 1C
   6.  Double roof & double wall
   7.  Roof spray mist - surface temp.            44.26C                 33·86C                 1O.40C
                        - air temp.               36.30C                 32·71C                  3.59C
   8.  Wall spray mist                            35.0C                  32.0C                   3.0C
   9.  Reflective materials
   9.  White colour - steel                       60.oC(White)           49.0C (Dark Blue)      11.oC
                   - brick                        33.5C                  33·0C                     o·SC
   11. Insulation materials
   12. Construction materials

   GENERATING AIR MOVEMENT

   12    Wind deflectors
   13.   Shape & orientation
   14.   Open plan
   15.   Jack roof or monitors
   16.   Openings
   17.   Courtyards

   DAYLIGHTING

   HYBRID


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5. Conclusion

         Since time immemorial the sun has always been in its present position and will still be
there until annageddon. It is time we adopted the idea of solar electricity and incorporate the
system with building design. The aim is to reduce the rate of depleting the fossil fuel for energy.
Tapping the energy from the sun has manifold advantages but due to high cost of PV technology
at the moment the best approach is to design with passive design first followed by purchasing EE
products and depending on individual's or company's affordability the fourth strategy i.e. the PV
system would be the last resort.
         Further researches would not only bring down the prices but also the panels can be
smaller in dimensions like the size of existing roof tiles with more efficient absorption capabilites.
That would open up to more creativive roof designs and not follow strict technical PV technology
rules that can give a monotonous and boring skyline.


References:

    1. Welcoming and Opening Speech by Y.Bhg. Dato' Abdul Rahman Husin, Deputy
       Director General (Sectoral Planning Division), Economic Planning Unit, Prime Minister
       Department, Government of Malaysia, Policy and Financial Frameworks promoting
       Sustainable Photovoltaic (PV) Markets, 13 September 2005, Hilton Hotel, Kuala
       Lumpur.
    2. Suruhanjaya Tenaga, DANCED & CETREE, Panduan Kecekapan Tenaga di Rumah, 2nd
       Edition 2003, ISBN 983-40909-3-5
    3. Pusat Tenaga Malaysia, Solar Energy Roadshow Study, 2005.
    4. Abdul Malek Abdul Rahman, Low-Energy Cooling Technology for Malaysian Homes,
       2004, Universiti Sains Malaysia Publisher, ISBN 983-861-274-X
       Jessica Williams, Fifty Facts that Change the World,




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