dissertation

A Dissertation Report

on

Solar Shading & Tracking

as a Key Code for

Building Integrated Photovoltaic Application

in

Indian Tropical Context

Guide: Prof. Ashok B. Lall

Sumanyu Vasist

0441731604

University School of Architecture and Planning

Guru Gobind Singh Indraprastha University Kashmere Gate, Delhi


Kashmere Gate, Delhi-6

Dissertation Title

Solar Shading & Tracking

as a Key Code for

Building Integrated Photovoltaic Application

in

Indian Tropical Context

Approval Certificate

The following study is hereby approved as a creditable work on the approved

subject, carried out, and presented in a manner sufficiently satisfactory to warrant its

acceptance.

It is to be understood that by this approval the undersigned does not necessarily

endorse or approve any statement made, opinion expressed or conclusions drawn

therein, but approve the study only for the purpose for which it is submitted and

satisfies himself as to the requirements laid down by the dissertation committee.

Name of the student Name of the Guide

Sumanyu Vasist (Prof. Ashok B. Lall)

0441731604

Introduction 01

The Setting

The Central Concept 03

The Tropics 05

Indian Solar Context 06

The Issue and Methodology 08

Case Studies 10

1. Denmark: Brundtland Centre 11

2. Spain: Univer 12

3. The Netherlands: Energy Research

Foundation

13

4. Italy: The Children’s Museum of Rome 14

5. Japan: S.B.I.C East Building 15

6. Germany: Fraunhofer ISE 16

7. The Netherlands: Le Donjon 17

8. UK: Jubilee Campus Nottingham University 18

9. A Chart: Features of case studies 19

Lessons Learned 20

Conclusions 23

Appendix 1. From PV cells to module to arrays 25

2. Sunlight in different regions of the world 26

3. Day lengths in different regions of the world 26

4. Comparative analysis of solar context 27

5. Global radiations in Indian sub-continent 27

6. Tax and excise benefits for solar technologies 28

7. R & D projects on Solar PV Program in India 30

8.List of figures and Photographs with sources 31

9. References 32

Acknowledgements 34

Introduction Photovoltaic (PV) power's potential for wide distribution makes it a

unique and novel energy source that can be embedded within the fabric of

individual buildings, while shifting power generation away from being large-

scale and regionally located. As a consequence, a free, clean and silent electrical

supply can be introduced into cities, towns and built-up areas.

Building-integrated photovoltaic (BiPV) involve combining solar

photovoltaic electricity technologies with those of building construction. This

subject is of great interest to those in the fields of energy conservation and

building design. Its significance, however, cannot be underestimated in the

context of the more familiar notion of sustainable development. The concept of

sustainability is more relevant than ever; it is a dynamic process that enables all

people to realize their potential, and improve their quality of life in ways which

simultaneously protect and enhance the Earth's life-support systems. PV

addresses these essential aspects.

The current level of fossil fuel power generation is by far the greatest

barrier to a state of sustainable equilibrium. Photovoltaic energy is already

making a significant contribution towards the transition to 'renewable' sources -

the key to achieving a sustainable society.

The relevance of BiPV in a sustainable world becomes clear after close

examination of the three words in the acronym:

Building(s) protect against the extremes of climate. They evoke mood;

they can excite, delight, and create a sense of wellbeing and repose. In the

developed world, buildings also account for approximately one half of all energy

consumed. The current energy generation process and reliance on fossil fuel

sources is one of the major threats to achieving sustainable goals for the building

sector.

Integrated means interdependence and interaction. In a sustainable

world, it is recognized that each action has consequences beyond the specific end

at which it is aimed. The construction of a building may successfully

accommodate and enhance the activities contained within it, but it will also have

an effect on its immediate physical setting, the climate, the neighbors and local

community, the region and, ultimately, the globe itself. Sustainable development

endeavors to anticipate these effects and, through integration with one another,

ensures that adverse effects are minimized and, if unavoidable, are in some way

balanced by those that are benign or of equal value.

Integration in sustainable development therefore seeks to reduce and

harmonize detrimental environmental impacts. It also seeks economy of means

and of materials in developing new industry opportunities. This, in the right

1

hands, promotes elegant design. The goals of integration in PV are just those of

sustainable development.

Photovoltaic is a technology whereby sunshine is converted into

electricity. Just as plants use chlorophyll to photosynthesize the sun's irradiation

in order to provide energy for their growth, a building can use particular

composite solar components to meet the energy needs of its occupants. Only 14.4

per cent of sunshine survives filtering from the Earth's atmosphere and falls on

land where it can be harvested. This is, however, 2,800 times more than our

energy needs!

With intent of thinking beyond oil and emerging awareness towards

harnessing renewable sources of energy, Building Integrated Photovoltaic

provides a great option. This is altogether a new concept and idea. Hence, its

viability in different parts of the world is a serious concern.

As we know that the sun behaves differently in different parts of the

world, thereby specific and directed strategies must be adopted for the

application of Integrated Photovoltaic. This would help to develop a dedicated

code for the specific regions of the world, hence maximizing the efficiency of

harnessing this free, clean and silent solar energy in that specific region of the

world.

Since, every region is unique not only in terms of its solar geometry but

also true to its regional aspects like incorporation of scientific and technological

breakthroughs, government schemes policies and intents, support for research

and development, vision towards sustainability and solar power, vision of that

region for the future at large.

The above forms the broader setting of this dissertation and the research

at large. This dissertation is directed towards architects, designers, clients, policy

makers, students and people in instrumental positions who are sensitive towards

the greater idea of sustainable future by incorporation of technological

advancement and breakthroughs in most efficient, clean and bionic ways.

This dissertation is specific to the technological wonder and bio-mimicked

concept of Building Integrated Photovoltaic, directed towards its application in

the tropical regions of the world focusing the Indian context.

Under the above framework, the hypothesis of this dissertation is

Solar shading and tracking as a key code for Building Integrated

Photovoltaic application in Indian Tropical Context

2

The Central Concept Solar power is the most reliable source of electricity in the world today.

Photovoltaic modules generate electricity when they are exposed to sunlight. The

actual creation of usable electrical current in a solar cell takes place at the atomic

level. The most commonly available solar cells are made from high-grade silicon

that is treated with negatively and positively charged semi-conductors,

phosphorus and boron. This process is called `doping’. When light energy

(photons) strikes the face of the cell, it excites the electrons within the cell. This

flow of electrons (current) from the negative semi-conductor (phosphorus) to the

positive semi-conductor (boron) is what we call the photovoltaic (PV) effect.

Fig: 01. Diagram of the PV effect

3

The Building Integration Attributes to Photovoltaic Of the various renewable energy sources, photovoltaic power is the only one

whose hardware lends itself to composite manufacture with conventional

building materials such as glass, metal and plastics [See Appendix-1]. From the

point of view of the architect & engineer considering the incorporation of PV, the

product is available in the same way as any other building component, but also

in a variety of forms and with very particular installation requirements.

It is this ability to offer the same attributes as a conventional building component

and its versatility in application that makes PV uniquely suitable for building

integration

Advantages of Building Integrated Photovoltaic • Building Integrated Photovoltaic systems can provide the function of

protecting the building envelope from the weather, avoiding the use of

other more expensive conventional cladding or roofing materials. The

avoided cost of these materials is subtracted from the installation cost of

BIPV improving their economics. However, in order to be effective, BIPV

products should match the dimensions, structural properties, qualities,

and life expectancy of the materials they displace.

• Building Integrated Photovoltaic produce electricity at the point of use

avoiding transmission and distribution of electricity and the costs and

losses associated with this. Regarding especially grid connected systems;

the building owner is also capable of obtaining significant revenues by

selling the surplus electricity generated to the utility grid so that the high

initial cost of BIPV will surely be considered as a financially beneficial and

viable investment.

• Photovoltaic on buildings uses existing infrastructure. No further ground

area is needed to tap the sun as a source of energy. This is particularly

significant in the densely populated areas with regard to solar energy

supply in the future.

• Synergies with other parts of the building envelope reduce additional

investment costs (winter garden, balcony roofs, etc.). Photovoltaic

modules are components in the building envelope.

• Photovoltaic modules are an architectural expression of innovation and

high technology. In particular, they enhance the public image of a

company when used as a component in prestigious facades of the

company buildings.

• The architectural quality of a PV facade gives an alternative to other well-

established cladding materials (PV instead of marble?)

4

The Tropics

Fig 02: Tropical regions

The tropics are the geographic region of the Earth where the sun passes

through the zenith twice during the solar year (once as the sun appears to go

north and once as it appears to go south). At the limits, called the tropics of

Cancer and Capricorn, this occurs once at the relevant solstice.

This area is centered on the equator and limited in latitude by the Tropic

of Cancer in the northern hemisphere, at approximately 23°26' (23.4°) N latitude,

and the Tropic of Capricorn in the southern hemisphere at 23°26' (23.4°) S

latitude.

Sunlight in the tropical regions has a typical nature, the sunrays fall quite

normal to the surface [See Appendix-2]. The sun angle is very less hence

restricting the exposure of sun to vertical elements, which in turn restrict the

exposure of the sunlight to the vertical parts of the buildings such as facades.

Hence the integration of PV is most efficient in the horizontal elements of the

building for maximum exposure.

Tropical regions have longer exposure to light as the daylight remains for

longer period of the day [See Appendix-3] which is really an added advantage

which is only there in the tropical regions of the world for the installation of PV

Because of the above set-up, application of PV in solar shading [see

Appendix-4] becomes an impotent aspect for the tropical regions as it not only

catches sun (give shade and shelter) but is very efficient as it gets maximum

exposure to the sunlight.

5

The Indian Solar Context Indian tropical context is more or less same to the tropical context of the

world. It also posses same features like of sun angles, longer day lengths and

high radiations.

India's power sector has a total installed capacity of approximately

1,44,913 Megawatt (MW) of which 60% is coal-based, 25% hydro, and the balance

is the gas and nuclear-based. Power shortages are estimated at about 11% of total

energy and 15% of peak capacity requirements and are likely to increase in the

coming years. In the next 10 years, another 10,000 MW of capacity and

investment of about Rs. 24 lakh crore are required.

Fortunately, India lies in sunny regions of the world. Most parts of India

receive 4-7 kWh of solar radiation per square meters per day with 250-300 sunny

days in a year [See Appendix-5]. India has abundant solar resources, as it

receives about 3000 hours of sunshine every year, equivalent to over 5,000 trillion

kWh. India can easily utilize the solar energy or Solar Power. Today the

contribution of Solar power with an installed capacity of 9.84 MW, is a fraction

(less than 0.1 percent) of the total renewable energy installed 12,632.67 MW (as

on 31march 2008 by MNRE).

The emergence of the solar electric architecture is not only an outcome of

the positional or geographical context of India but also because of the

sentimental set-up in India. Prime Minister of India unveiled a National Climate

Change Action Plan in June 2008. The plan will be implemented through eight

missions with main focus on solar energy in the total energy mix of the country.

Fig 03: Quote of Hon Prime Minister of India on solar energy

Also there are numerable rebates and tax benefits available [See

Appendix-6] for the production, manufacture, distribute and market the

products related to solar power. Also special customs and excise duty benefits

are provided as part of the overall policy to develop, promote and encourage the

use of solar power in India.

The Research and Development (R&D) efforts in the Solar Photovoltaic

technology have been aimed[ See Appendix-7] at development of materials used

in fabrication of Solar cells and modules, different types of Solar cell device

6

structures, module designs, components, sub-systems and systems, with a view

to reduce the cost and improve the overall efficiency at different stages.

Truly, Indian solar context gives an apt setting (geographical and

intentional) for the incorporation of solar technologies which addresses the

greater idea of sustainability at large.

Solar shading as an inherent concept of Indian Architectural prospect Because of the Indian climatic set-up, solar shading always had been an

inherent part of Indian Architecture. Be it traditional or modern, in every era

solar shading was an intrinsic part of the building design. Many times, solar

shading elements and devices were a significant part of the architectural

expression and emotion. Every climate responsive design and interventions in

India, kept in mind the idea of solar shading.

Elements like eaves, sunscreens, louvers etc are an integral part of the

overall Indian architectural language. Atriums/courtyards, canopies and

pergolas are intrinsic part in Indian architecture. They are not only considered

significant but also many times celebrated by elaborate design attentions.

Hence, the standing of solar shading elements and concepts is very high in

climate responsive Indian architectural expression and is true to the regional

aspects of Indian tropical context.

7

The Issue In the circumstance of the present global state of affairs, it is palpable to give

importance and preference to the technological aspects which respond and

respect the greater notion of sustainability. With the idea of thinking beyond oil,

the pressure of developing and incorporating new technologies relating to

energy conservation are greater than ever. There is an extended pressure on large

oil importing nations like India to harness their renewable sources of energy to

greater extends.

India lies in the sunny regions of the world. Moreover, the intentional set-up is

very favorable, where governmental policies, vision, support of research and

development, etc. all provide a platform for the implementation of energy

related concepts. Hence the emergence of solar electric architecture in India is

inevitable. One of the obvious technological options available is Building

Integrated Photovoltaic, which respects, reflects and relates to the larger idea of

sustainable developments at large.

Since, there are exclusive aspects for the Indian tropical context; it would have an

obvious reason to explore the codes for the same and combining them with the

advanced technology available. Hence, the need for the code for application of

Building Integrated Photovoltaic was felt.

Since in the Indian set-up, the code must be highly efficient and multi-

dimensional, so as to discount the factor of affordability (an important issue in

India). Moreover, the code must be true to its regional qualities so that it is

accepted with least resistance. Under above formwork, it was realized that Solar

Shading and tracking is a key code for the application of Building Integrated

photovoltaic in the Indian Tropical Context.

Solar shading which is an integral part of the Indian architectural language and

expression and truly respond to the Indian solar context is taken as a key code

for its regional qualities and acceptance. Also, it’s obvious that these are the

elements which are used to catch the sun and also give shelter.

Solar tracking is seen as a code as it increases the efficiency hugely, which was

very much required for this part of the world.

Consequently, this code will (a) give shade and shelter (because of its application

in shading elements) (b) give useable energy (because of the PV application on

those areas) (c) give very high efficiency (because of the tracking of the sun).

This dissertation claims: Solar Shading and Tracking as a Key Code for the

Application of Building Integrated Photovoltaic in Indian Tropical Context.

8

Methodology This dissertation aims to develop a code for the PV application in Indian

Tropical Context. In accordance to the hypothesis, it was appreciated that Solar

shading and tracking is the code for the same.

The methodology adopted would be the careful analysis of different case

studies taken up from various sources. These case studies form the basis of this

dissertation. The case studies would stringently be filtered through the two main

concepts of solar shading and tracking. They will be chosen which seem to

demonstrate the hypothesis.

General heads of the case studies would include the objective or intent of

the client, type of integration, specific material technology and costing.

Under the formwork of the above, the inferences will be drawn. The inferences

will show what all lessons are learned from the matrix of the case studies. These

lessons learned would be the background of the conclusion for this dissertation.

9

Case Study 01

DENMARK: BRUNDTLAND CENTRE

1,922 hours per yearSunshine Hours

NewNew/ Retrofit

CommercialBuilding Type

Roof, canopy and facade systemsType of PV building

DenmarkCountry

ToftlundLocation/City

14.25 kWpProject

PV DesignTwo types of PV system were used in the building envelope. A PV array was integrated into the roof of the atrium, a central space connecting the adjacent two-storey buildings. Another array of PV modules was mounted on thesoutheast facade of the office section. The atrium roof, incorporating transparent PV modules, stretches out above the entrance of the building, creating a large canopy. The steel truss roof, combined with the alternating pattern of dark, round cells against the transparent glazing, gives the atrium a high-tech atmosphere. Special attention was paid to providing a soft diffuse quality of daylight in the interior of the atrium. The vivid blue color of the PV system integrated in the facade has an even greater impact on the building's image.

Energy & Performance:PV Power generation: 13,500 kWh per annum (DC)PV exported to the grid: 11,000 kWh per annum (AC)Provision and control of daylight, combined with high-efficiency artificial lighting and movement sensors saved approximately 70% of electricity for lighting compared to traditional office lighting designs..

Fig 04: View of atrium

10

Case Study 02

SPAIN: UNIVER

Yearly average = 4.9 hours per daySunshine Hours

Retrofit and new (pergola)New/ Retrofit


Facade-integrated, pergola (building canopy), parking canopy

Type of PV building

SpainCountry

JaenLocation/City

200 kWpProject

PV Design

The installation is divided into four PV sub-generators with different architectural solutions and configurations (PV generators and inverters). ). The intention was to analyze the performance of different PV modules (mono- and poly-crystalline), inverters (central inverter or string oriented inverters) and the potential for use on buildings such as pergolas, parking canopies and facades in the south of Spain, especially in Jaen.

The pergolas provide shade and shelter to the area, hence giving double benefit. The idea of incorporation of PV in parking canopies is a smart decision as these canopies are used to catch the sun and give shade to the cars below and also act as a power generator

Energy & Performance:

Since the UNIVER project annual PV yield is around 250 MWh, its related environmental benefits include an annual remission of 125 tonnes of carbon

dioxide and 350 kg of sulphur oxides.

Fig 05: View of pergola

11

Case Study 03

INDIA: PEDA OFFICE COMPLEX

2000 hours per yearSunshine Hours

NewNew/ Retrofit

Office complexBuilding Type

Atrium/Skylight and Roof integrated systemsType of PV building

IndiaCountry

Chandigarh, PunjabLocation/City

Punjab Energy Development Agency (PEDA) Project

PV Design

The three-dimensional form of the building has been developed in response to the solar geometry of that region. The solar photovoltaic at the roof level would be used to run the lighting and cooling systems. On cloudy days, it would have two day battery back-up to run machines.

The introduction of building integrated PV in the roof area is not only a design feature but also provide diffused light beneath it. This way the PV panels provide double benefit of producing free and clean energy for the users and

also creating a semi-shaded space for the office block

Energy & Performance:Mr S.S Sukhon, Director PEDA said`Against the normal requirement of 200 kW power load, we will take only 80 kW

connection to run the system. Rest of the power demand requirements would be met by solar power plant. Besides that additional power produced on weekends and holidays would be sold to the UT grid. ‘

Fig 06: View of Front

Fig 07: View of Interior

12

Case Study 04

THE NETHERLANDS: ENERGY RESEARCH FOUNDATION(ECN) - BUILDING 31


RetrofitNew/ Retrofit

Office building and research laboratories Building Type

PV lamella (tracking) system, canopy and curved roof integration

Type of PV building

NetherlandsCountry

PettenLocation/City

Energy Research Foundation (ECN) —Building 31Project

PV Design

PV Design include lamellas as shading devices. Each metal lamella was to be about 840 mm wide, 3000 mm long and covered by three standard poly-crystalline PV modules. The lamella at eye-height for a sitting person working in the interior is moveable, to allow exterior views. The rear of the metal lamellas has holes for ventilation of the PV panels. Each string consists of 42 standard modules from the lamellas and 12 transparent modules from the canopy. These shading elements give both shade and power. With the incorporation of the tracking system the efficiency increased hugely.

Fig 08: Lamella Shading System

Fig 09: Lamella Shading System with elevation and section

Fig 10: Integration of PV molecules into metal shading system

13

Case Study 05

ITALY: THE CHILDREN'S MUSEUM OF ROME




Roof and canopy (tracking) integrated systemsType of PV building

ItalyCountry

RomeLocation/City

15 kWpProject

PV Design

The first PV design approach proposed a moveable 3 kWp PV roof structure that would shelter the large skylight, and 12 kWp moveable canopies shaped like a 'Meccano' toy, placed along the south facade. The cost analysis demonstrated that the solution of replacing conventional glass with double-glazed PV modules in the skylight reduced the cost of the PV installation and also eliminated the cost of maintenance of the mechanical roof structure. The PV skylight also contributes significantly to improving the overall indoor comfort and the aesthetic quality of the roof.

There was not a specific requirement to use photovoltaic, but the exposure of children to alternative energy was considered to be an effective illustration of the basic aim of this museum: to heighten awareness of the quality of urban life through 'a transparent guided itinerary' of everyday activities.

Energy & Performance:The estimated overall energy directly produced by the PV will be18,000kWh/year, but the PV used as a passive cooling and heating device will reduce the consumption of energy for heatingThe energy produced will be directly used in the museum.

Fig 11: View of skylight

14

Case Study 06

JAPAN: SBIC EAST BUILDING




Roof and canopy (tracking) integrated systemsType of PV building

ItalyCountry

RomeLocation/City

15 kWpProject

PV Design

The SBIC East building has four types of BiPV: eave-type array on pergola; inclined-type array on roof; furring-type array on parapet; and shade louver-type array.

Energy & Performance:The SBIC East building system has operated well since April 1998. The system

provided 30,400 kWh electricity

Fig 12 : PV vertical Louvers

Fig 13 : PV Shade Louvers Fig 14 : PV Eave Type Array on pergola

15

Case Study 07

GERMANY: FRAUNHOFER ISE


NewNew/ Retrofit

Research facilityBuilding Type

Atrium and façade integrated systemsType of PV building

GermanyCountry

FreiburgLocation/City

20 kWp Fraunhofer Institut fuer Solare Energiesysteme ISEProject

PV Design

The main entrance foyer is dominated by an atrium with a saw-toothed roof and integrated PV modules. External blinds with a light-redirecting function provide solar control. The saw-toothed roof over the atrium offers some 70 square meters of area for PV modules and is a good example to illustrate the design process. Good daylighting conditions are essential for the use and the aesthetic effect of an atrium. . The first geometry was chosen yielding an inclination of the shed-skylights near the optimum of 35°.

There was special attention given to the semi-shaded space beneath the skylight. The skylight was designed to give an architecturally pleasing feel and responsive to the solar geometry to give pleasing architectural expression and generate usable energy

Energy & Performance:An annual yield of around 16MWh is expected for all the PV systems, which should meet the entire demand for office lighting in the building

Fig 15: View of roof

16

Case Study 08

THE NETHERLANDS: LE DONJON


NewNew/ Retrofit

Office buildingBuilding Type

PV canopy above facades Office buildingType of PV building

NetherlandsCountry

GoudaLocation/City

Le DonjonProject

PV DesignThe PV modules are produced as custom-sized frameless laminates. The transparent back foil allows a semi-transparent visual appearance. The use of PV modules as little roofs above walls for buildings with flat roofs was a good strategy, especially as the roofs are small and the attic walls will shade part of the roof. The PV modules therefore:•function as rain protection for the attic walls and substitute a horizontal metal covering;•protect the facade from rainwater;•Could function as sunscreens.For design reasons (rainwater flush) the PV canopy was designed to run around the roof with a uniform inclination of 5° to the horizon. For that reason, the PV elements are all inclined to the centre of the roof, so the PV modules on the south side are 5° inclined to the north and so forth.

Energy & Performance:PV system 6.2 kWp

Fig 16: North Facade

17

Case Study 09

UK: JUBILEE CAMPUS NOTTINGHAM UNIVERSITY


NewNew/ Retrofit

EducationalBuilding Type

Roof-integratedType of PV building

United KingdomCountry

NottinghamLocation/City

Jubilee Campus Nottingham UniversityProject

PV DesignThe PV cells are an integral part of the atria roofs within the school of management, the department for computer science and the faculty of education. They provide shading to the spaces below and replace the glazing system with laminated glass panels with integrated square PV cells.It was realized that the application of shaded PV application is also extended to the connecting corridors and spaces, which enhances the scope of Building integrated PV applications. This strategy not only provide the required shade and shelter to the connecting spaces but also generates usable power.

Energy & Performance:The total energy output of the PV installation is 51 MWh per year with a peak output capacity of 53.3 kW

Fig 17: Roof showing solar shading

18

Lessons Learned We are already aware of the significance of solar shading & tracking (as a

concept) in the Indian tropical regions. Giving it a designation of a key code was

inevitable and obvious. Hence, solar shading & tracking as a key code for

Building Integrated Photovoltaic application in the Indian tropical scenario come

up with a Triple bonus (a) Provides shading, which is the basic function, (b)

Provides power, as it catches sun and convert its energy into usable form, (c)

High efficiency, as it tracks the sun. Demonstration of the same was seen in the

previous chapter.

Each case study and example is peculiar in nature and provides us with a

valuable and viable input which would eventually help in drawing key code for

the Integrated Photovoltaic application. Numerous lessons were learned during

the compilation of the case studies which in turn provided a great formwork of

this dissertation.

In the Indian tropical set-up, the building envelope provides a number of

possibilities for the integration of Photovoltaic. Taking solar shading is a leading

concept, elements like sunscreens and louvers, eaves, aria and skylights,

canopies and pergolas become key areas for the desired photovoltaic

applications.

Sunscreens and Louvers: Building designs in Indian Tropical situation

provides a suitable integration of all types of screens and louvers. See Case Study

[6] where numerous options for the integration of PV are demonstrated, from

vertical louvers to furring-type array on roof. Also See Case Study [4], where

lamella façade shading & tracking system is designed, which provide greater

efficiency and the required shade to the building.

Eaves: In the tropical regions of the world eaves have a special place as

they not only provide shade to the building façade but also act as a rain

protection element for the vertical walls of the building. Hence they are generally

articulated and given great significance. See Case Study [6] where semi-

transparent eave array was used as one of the design feature. Also, See Case

Study [8], which is an excellent example of this type of integration, it was

realized that, it have a greater viability in dense urban scene where there are

large dimensions of exposed roof profile and very less non-shaded vertical

surfaces.

Atria and Skylights: Possibly one of thee most elaborate and

architecturally invigorating applications of PV has been in Atria and Skylight

systems. See Case Study [1] and Case Study [7] where this integration generates

20

not only electricity for the use, but also a pleasing and semi-shaded atrium

beneath. Also See Case Study [3] where a remarkable architectural expression

was achieved by the incorporation of these PV modules in the skylight roof

providing enough daylighting requirements, architecturally pleasant semi-lit

space and of coarse generation of power. Its relevance extend to the connecting

corridors and spaces, see Case Study [9] where an expressive connecting space is

realized by the incorporation of PV array into the glazed roof. This integration

also try to demonstrate an idea to the viewer/user and make him conscious of

the building systems, see Case Study [5] were the skylight is integrated with PV

to demonstrate an idea of conservation of solar power in addition to the obvious

reasons.

Canopy and Pergolas: The need for the canopies and pergolas are not only

for an advanced architectural experience and expression but also these elements

provide shade, shelter and cooling effect in the sunny regions of the world. See

Case Study [2] where the integration of PV in pergola and in parking canopy

makes a great architectural solution. Also see Case Study [5] where solar tracking

canopy forms an integral part of the design, making it very efficient. It was found

that the indoor climate and natural quality of the light would benefit

substantially from the mechanical moveable elements in the canopy.

It is a lucid idea that installation of tracking systems with the shading

elements in the integrated photovoltaic application would increase the efficiency

of the system. See Case study [4] where mechanical tracking lamellas are

installed which increases the overall efficiency of the installations and also

provides the user with desired shading options. Amazingly, sometimes when the

system is well designed and responsive, the increased efficiency of PV discount

many costs. See Case Study [5] where it was realized after the cost analysis, that

the solution of replacing conventional glass with double-glazed PV modules

reduced the cost of the PV installation and also eliminated the cost of

maintenance of the mechanical roof structure.

Integrated photovoltaic application provides with many options,

generally it is a part of the holistic design like in Case Study [1] where an

conscious effort was made to incorporate PV integration. A startling case was

Case Study [3] where truly the holistic approach was included, where three-

dimensional form of the building has been developed in response to the solar

geometry. Case Study [7] and Case study [4] include PV installation at particular

angles to truly respond to the solar geometry of the region.

Not only in new constructions but also in older constructions this

technology can go hand-in-glove. See Case Study [2], Case Study [4] and Case

21

Study [5] where the buildings are retrofit. Also see Case Study [6] in which the

idea of incorporating PV as a shading element came very late but worked

beautifully.

Hence, the flexibility and freedom which is given by this innovation is

immense and will clearly find way in any region of the world especially in

Indian Tropical set-up where solar shading concepts are inherent to the regional

architecture and expression.

The usable energy produced by this system is generally utilized by the

building itself and some of them give the excess electricity to the UT grid, which

in turn pay the company a handsome rewards. See Case Study [1], this way the

energy losses during the transmission and maintenance of electricity are

discounted further. Also an excellent example is of Case Study [3] where the

building required only 80kW power load than 200kW, they also have a back-up

of two days, additional power is given back to the grid. This will be of

tremendous benefit for the Indian energy scenario, which is why government not

only encourages these initiatives and ideas but also give grants and tax benefits

for the demonstration of such innovations.

It was interesting to know that, many of these projects were a

demonstration of an idea or an image. Sometimes to educate like in Case Study

[5], somewhere it matches the company’s vision, see Case Study [8], and

sometimes it’s the show of the client’s sensitivity to wards the energy issues like

in Case Study [3]. Hence, it not only respects but also reflects the idea and notion

of energy consciousness at large.

There were many projects which were funded by different govt. & non

Govt. organizations, this reflect that the technology is expensive but the

governmental set-up want to promote this, as it feels that it is good for the future.

Moreover as the cell technologies and efficiencies are developed, the factor of

affordability is discounted.

Needless to say every Case Study someway or other contributes to the

greater idea of sustainable growth and development by saving energy and

cutting the emission of harmful gases to the atmosphere. This noble idea can

very well be addressed in many ways, on of the way is by careful incorporation

of technological advancement and breakthroughs in most efficient, clean and

bionic ways.

22

Conclusions The energy demand in the emerging economies of the world – including

India and China – is projected to be double over the next quarter- century. Hence

there is a pressure on these economies to extend, develop and incorporate the use

of technological advancements and breakthroughs to their advantage and

harness the renewable sources of energy (like solar power through Building

Integrated Photovoltaic).

Being a tropical nation, India provides an apt solar setting for the

application of the same. Nevertheless, India always reflect, respect and responds

to the vision of sustainable growth at large. Hence provide a pertinent setting

(both geographically/climatically and intentionally) for the application of the

Integrated PV in buildings. Because of India’s unique context, the need for codes

for the PV application in Building was felt. This dissertation deals with the same.

Numerous lessons were learned during the compilation of case studies (as

stated in the previous chapter) and it was comprehended that solar shading and

tracking have the potential to be a Key code for the application of Building

Integrated Photovoltaic in Indian Tropical Context. Architects, designers,

engineers have done this in many part of the world but this concept of

Application of PV with shading & tracking holds a strong viability in this part of

the world.

We must not forget that solar shading is an inherent concept of the

architectural emotion and expression in India; hence integration of PV with this

concept increases its capability and acceptability. This way the application of PV

becomes truly `integrated’ with the build environment in Indian setup, true to its

regional sentiments and aspects. Also, solar shading elements till now were only

catching the sun and giving shade and shelter, but with the integration of PV it

started generating usable power which is clean, free and relates to the greater

idea of sustainability.

Solar tracking as a code straight away directs towards the need for a

highly efficient system. Higher efficiency is directly related to the payback time,

and discounts the factor of affordability (which is an critical factor in the Indian

context)

Hence it would be unambiguous so state:

Solar Shading & tracking as a Key Code for the application of

Building Integrated Photovoltaic in Indian Tropical Context.

23

As a consequence of adopting the stated strategy, many challenges seem to be

addressed like;

Cost: Since the code clearly reflects the idea of high efficiency and less

payback time, the cost and the affordability factor is discounted.

Land: Since the application is an integral part of the build-up area no extra

land is required for its application.

Integration: The code truly integrates with the coherent aspect of the

Indian architectural language that is solar shading. Also the modules can be well

integrated with existing and new structures in an architecturally pleasing way, as

seen in case studies.

Expression: Its integration truly reflects and respects the larger idea of

energy consciousness and sustainability.

Efficiency: Not only solar tracking but also the integration of PV in

building add to the efficiency, as it discounts the transmission and distribution

costs of electricity.

Harnessing the renewable (solar) energy: This way it can produce a free,

clean and silent power with minimal dependence on conventional sources of

energy and save/ reduce the emission of huge amount of harmful gases into the

atmosphere.

Plays nature’s idea: like tree leaves gives shade and shelter and also

generates energy for its own. Similarly, PV applications give shade and shelter

beneath and also generate useable power for the building, truly a bio-mimicked

concept and idea.

This dissertation would achieve its mission if it can attract the interest of

its target group, namely architects, designers, clients, policy makers, students

and people in instrumental positions who are sensitive towards the greater idea

of sustainable future by incorporation of technological advancement and

breakthroughs in most efficient, clean and bionic ways.

24

Appendix 1

From cells to module to arrays

25

Appendix 2

Sunlight in different regions of the world

Appendix 3

Day lengths in different regions of the world

26

Appendix 4

Appendix 5

Global radiations, annual mean

27

Appendix 6 Tax Benefits Accelerated Depreciation benefits allowed for solar products

• Flat plat solar collectors

• Concentrating and pipe type solar collectors

• Solar cookers

• Solar water heaters and systems

• Air / gas / fluid heating systems

• Solar crop driers and systems

• Solar refrigeration, cold storage and air-conditioning systems

• Solar stills and desalination systems

• Solar power generating systems

• Solar pumps based on solar thermal and solar photovoltaic conversion

• Solar photovoltaic modules and panels for water pumping and other applications

• Wind mills and any specially designed devices which run on wind mills

• Any special devices including electric generators and pumps running on wind energy

• Biogas plant and biogas engines

• Electrically operated vehicles including battery powered or fuel-cell powered vehicles

• Agricultural and municipal waste conversion devices producing energy

• Equipment for utilizing ocean waste and thermal energy

• Machinery and plant used in the manufacture of any of the above sub-items

Customs and Excise Duty

(A) CUSTOMS DUTY

*Peak rate of basic customs duty unless specified is 10% (Notification No. 21/2002 item No 86, condition 5)

1. The following goods, namely:

• Silicon in all forms, that is, polycrystalline silicon or ingots, for the manufacture of undiffused

silicon wafers; NIL

• Undiffused silicon wafers, for The manufacture of solar cells or Solar cell modules;

(Chapter No. 85 item No. 8541.40)

2. Photovoltaic cells whether or not assembled in modules or made up into panels NIL

• Solar Cells NIL

• PV Modules

(Chapter No. 94 item No. 9405 50 40)

28

4. Equiment gadgets based on solar energy 7.50%

(Notification No 25/99, List A, Items no 7,18 %38)

5. Specified raw materials for manufacture of solar cells and module Nil

EXCISE BENEFITS for FY 2007-08

As per Notification No 6/2000 Item no 237, list 9

1. Specified Non Conventional Energy Devices / Systems

These Include the following

• Flat plate solar collectors

• Black continuously plated solar selective coating sheets (in cut lengths or in coils and fins and

tubes)

• Concentrating and pipe type solar collectors

• Solar cookers

• Solar water heaters and systems

• Solar air heating systems

• Solar low pressure steam systems

• Solar stills and desalination systems

• Solar pumps based on solar thermal and solar photovoltaic conversion

• Solar power generating systems

• Solar photovoltaic modules and panels for water pumping and other applications

• Solar crop driers and systems

• Wind operated electricity generators, their components and parts thereof

• Water pumping windmills, wind aero-generators and battery chargers

• Bio-gas plants and bio-gas engines

• Agricultural, forestry, agro-industrial, industrial, municipal and urban waste conversion devices

producing energy

• Equipment for utilizing ocean waves energy

• Solar lantern

• Ocean thermal energy conversion systems

• Parts consumed within the factory of production of such parts for the manufacture of goods

specified at S.Nos.1 to 19 above

• Solar photovoltaic cells

29

Appendix 7

R & D projects on Solar PV Program in India.

• The Solar Energy Centre has been established by Government of India as a part of MNRE

to undertake activities related to design, development, testing, standardization, consultancy, and

training and information dissemination in the field of Solar Energy.

• Recently, development of polycrystalline silicon thin film Solar cells and small area Solar

cells concluded at the Indian Association for Cultivation of Science at Jadavpur University.

• The National Physical Laboratory, New Delhi is working on development of materials

and process to make dye sensitized nano-crystalline TiO2 thin films.

• The Centre for Materials for Electronics, Pune has been working on development of

phosphorous paste for diffusion of impurities in Solar cells.

• Under a joint R&D project of MNRE and Department of Science & Technology (DST), the

Indian Association for Cultivation of Science (IACS), Kolkata continued to work on optimization

of process for fabrication of large area double junction amorphous silicon modules.

• Indian Institute of Science, Bangalore to develop efficient electronic system for

connecting small PV systems to the grid.

• Indian Institute of Technology Bombay to work on development and testing of low

concentration PV systems.

• The scientists at the Indian Association for Cultivation of Sciences, Jadavpur continued

their work on development of nano and multi junction silicon thin film Solar cells and

optimization of the performance of multi junction thin film Solar cells through computer

modeling.

• A proto type solar car was successfully developed and demonstrated by the students of

Delhi college of Engineering. The car operates on Solar power, which is stored in storage

batteries. In one charge the car is capable of traveling about 70 km. The maximum speed of the

car was demonstrated at 60 km/hr. The Solar car was also displayed in the 9th Auto Expo held in

New Delhi during 10-17th January, 2009.

30

8. List of Figures and photographs Title/ Description Page

Cover Page PV incorporated, ENC Building 42, The Netherlands

Photographer: John Lewis Marshall

Cover

Fig 01 Diagram of PV effect

Source: Internet

3

Fig 02 Tropical Regions of the world

Source: Internet (www.wikipedia.com)

5

Fig 03 Quote of Hon Prime Minister of India on solar energy

Source: Internet (www.solarindiaonline.com)

6

Fig 04 View of atrium

Source: Book, Recent experiences in Building Integrated PV.

10

Fig 05 View of pergola

Source: Internet( www.ujaen.es)

11

Fig 06 View of Front of PEDA

Source: Internet

12

Fig 07 View of Interior of PEDA

Source: Energy-efficient Buildings in India

12

Fig 08 Lamella Shading System

Source: Architectural Quality of Building Integration of Solar Energy

– Case studies in The Netherlands.

13

Fig 09 Lamella Shading System with elevation and section


– Case studies in The Netherlands

13

Fig 10 Integration of PV molecules into metal shading system


– Case studies in The Netherlands

13

Fig 11 View of skylight

Source: ), La Stampa

14

Fig 12 PV vertical Louvers

Source: Building Integrated Photovoltaic designs for commercial &

Institutional Structures – A sourcebook for Architects

15

Fig 13 PV Shade Louvers



15

Fig 14 PV Eave Type Array on pergola



15

Fig 15 View of roof

Source: Internet (www.ise.fhg.de)

16

Fig 16 North façade


– Case studies in The Netherlands.

17

Fig 17 Roof showing solar shading



18

31

9. References

Introduction

David Lloyd-jones,Steven strong,Tjerk Reijenga; (2005), Designing with Solar Power

The Central Concept

Leenders, F. Van Der Ree & Prasad.DK; (2001), Photovoltaic Cogeneration in the Built

Environment

Building Integration Attributes to Photovoltaic

Wern.C & Barram. F; (2004), Solar Integration in Commercial Buildings

Advantages of Building Integrated Photovoltaic

Jackson T, Oliver M,. (2000) Viability of Solar Photovoltaic. Energy Policy 28

] M.M. Karteris, K.P. Papageorgiou and A.M. Papadopoulos, (2006). Integrated photovoltaics as

an element of building’s envelope.

The Tropics

] Koenigsberger, Ingersoli, Mayhew, Szokolay (2001) Manual of Tropical Housing and Building-

Climatic Data. Orient Longman Limited

] Patrick l. Osborne.(2000). Tropical ecosystems and Ecological concepts. Cambridge University

Press

Indian Solar Context

Bansal N.K, Mathur J (Indian Building Congress); (2008) Practical Handbook on energy

Conservation in Buildings

www.solarindiaonline.com

Case Study 1, DENMARK: BRUNDTLAND CENTRE

Collins. R, Davenport. T & Scahch .M, (2004), Recent experiences in Building Integrated

Photovoltaic.

Case Study 2, SPAIN: UNIVER

www.ujaen.es

Case Study 3, INDIA: PEDA OFFICE COMPLEX

Mili Majumdar (TERI & MNES); (2002) Energy-efficient Buildings in India

Case Study 4, THE NETHERLANDS: ENERGY RESEARCH FOUNDATION

Reijenga. T; (2000), Architectural Quality of Building Integration of Solar Energy – Case studies in

The Netherlands.

Case Study 5, ITALY: THE CHILDREN'S MUSEUM OF ROME

Wetzel. T, Baake .E & Muelbauer. A, (2001), La Stampa

32

Case Study 6, JAPAN: SBIC EAST BUILDING

Eiffert. P & Kiss. G.J; (2005), Building Integrated Photovoltaic designs for commercial &


Case Study 7, GERMANY: FRAUNHOFER ISE

www.ise.fhg.de

Case Study 8, THE NETHERLANDS: LE DONJON

Reijenga. T; (2000), Architectural Quality of Building Integration of Solar Energy – Case studies in

The Netherlands.

Case Study 9, UK: JUBILEE CAMPUS NOTTINGHAM UNIVERSITY

Eiffert. P & Kiss. G.J; (2005), Building Integrated Photovoltaic designs for commercial &


33

Acknowledgements

I would like to express my thanks to my guide Prof. Ashok B. Lall.

His advice, expertise and encouragement always pushed me to think new and

better. And, for parting his valuable time for this paper.

I would like to express my thanks to my year coordinator Architect

Arunav Dasgupta for leading us and always being around even in tough times.

His directions and guidance have a pivotal role in completion of this paper.

Also, thanks to my dear friends especially Garima, Swati, Sumeet,

Rahul & Sudhanshu who have given unconditional support to me. In addition, a

special thanks Liesbeth Vanbaelen of HB Design who also guided me in this

topic via emails and internet discussions.

Finally, thanks to the school friends, faculty and management for

their supportive role.

Sumanyu Vasist (0441731604)


dissertation

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