Potential solar power installations within the municipality of Uppsala

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STS18009

Examensarbete 15 hp

Juni 2018

Potential solar power installations

within the municipality of Uppsala

Clara Grönlund

Måns Wallentinsson

Linus Rustas

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Teknisk- naturvetenskaplig fakultet UTH-enheten Besöksadress: Ångströmlaboratoriet Lägerhyddsvägen 1 Hus 4, Plan 0 Postadress: Box 536 751 21 Uppsala Telefon: 018 – 471 30 03 Telefax: 018 – 471 30 00 Hemsida: http://www.teknat.uu.se/student

Abstract

Potential solar power installations within the

municipality of Uppsala

Clara Grönlund, Måns Wallentinsson, Linus Rustas, Emil Forsén

Uppsala municipality has ambitions to reduce greenhouse gas emissions by installing solar power. To do this, the municipality has set a goal to install 30 MWp of solar power by the year 2020, and today 25 MWp has yet to be installed. The objective of this study is to investigate if Uppsala municipality is able to install 25 MWp solar power on municipality owned buildings or if an additional solar park installation is required. This is done through simulations and calculations and results are visualized in QGIS, a geographical information system software. The conclusion of this study is that Uppsala municipality will need a solar park at a magnitude of 0.9 MWp and rooftop installations of 24.1 MWp to reach the goal of 30 MWp. The cost of this installation would be 296 MSEK. The GIS-layers illustrates municipality owned rooftops suitable for solar power installation and module installation proposals. A sensitivity analysis is performed were the type of module is changed, which in turn affects efficiency and module angles. The outcome of the sensitivity analysis is that the type of module and the module efficiency are important parameters that affect the result. Depending on how valuable the land area is, higher module efficiency could be advantageous. Future work could involve an investigation about which type of PV technology that best satisfies Uppsala municipality’s priorities.

ISSN: 1650-8319, UPTEC STS18 009 Examinator: Joakim Widén

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Definitions

Albedo The ratio of light that is reflected by a surface (a value between 0 and 1)

Azimuth Angle describing how an object is orientated with reference to south

Building polygon A polygon in a GIS layer representing a building GIS Geographic Information System

Irradiation model A script to calculate solar irradiation on building, see section 2.2.2 for further explanation

k-marked building Building protected due to historical and/or cultural values Layer A collection of georeferenced data, can be arranged as a

shapefile

LiDAR Light Detecting And Ranging data. LiDAR survey method utilise laser to measure the distance to an object

Map (QGIS) A collection of layers in QGIS. Could be arranged to show attributes from several layers in one visualization Maximum yield orientation The optimal azimuth and tilt of a solar module in terms of

power generation for a certain time period and location Solar Module An array of solar cells arranged to produce solar power,

also known as solar panel Photovoltaics (PV) Conversion of light to electricity Property map A map showing real estate in Uppsala q-marked building See k-marked building

QGIS An open source GIS software

Shapefile A vector-based file format used to store geographical data IEA International Energy Agency

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1 Introduction

Awareness about global warming has risen during the last decades. Global warming leads to a series of consequences such as longer and more intense droughts, melting glaciers, rising sea levels and harsher hurricanes. Most scientists agree that human activity contribute to these changes due to excessive usage of fossil fuels [1]. Many countries are trying to prevent global warming in order to create a better future for coming generations. Sweden has set up a number of climate goals, one of which is to reduce greenhouse gas emissions by 40% from 1990 to 2020. For instance, this will be done by raising public awareness, by making energy usage more efficient and by investing in energy sources with lower emissions of greenhouse gases [2]. In order to reach this goal, each and every one of Sweden's 290 municipalities has to take individual responsibility to lower their emissions.

The municipality of Uppsala is consequently working to minimize their emissions of greenhouse gases by expanding the usage of renewable energy. Action is taken in many ways, e.g. by initiating_{Uppsala Climate Protocol, a cooperation program to inspire local} private and public actors to contribute to the work towards climate goals set by the

municipality [3]. Besides investigating other types of renewable energy solutions, Uppsala has the ambition to become the municipality with the highest amount of solar-generated electricity; today it is in third place [3].

Uppsala municipality’s work with solar energy is one out of eight milestones that have been set for the environment and climate. This particular milestone entails raising the amount of installed solar power to 30 MW of peak rated capacity (MWp) by the year 2020 [4]. Part of the milestone has already been reached through different efforts from companies within the municipality, but the majority, 25 MWp, has yet to be installed. One challenge is to

determine how to distribute solar modules on the municipality's rooftops and land areas in order to maximize the power output, while at the same time satisfying preferences of how the goal should be met [3]. This bachelor thesis examines how the municipality, by own means, could arrange solar modules in order to reach the milestone of 30 MWp by 2020.

1.1 Purpose

The purpose of this study is to analyze how Uppsala municipality can reach the goal of 30 MWp installed solar power by 2020. Uppsala municipality wish to investigate the

possibility to reach this goal solely by installations on municipality owned rooftops, or if an additional solar park is required. An economical evaluation is also made considering

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1.1.1 Research questions

Following research questions are investigated:

1. Which municipality owned buildings are suitable for solar power installations? 1

2. What is the solar power potential of the municipality-owned rooftops?

3. If a solar park is required, what would the installed power be in order to reach the goal and what land area would be needed?

4. What would be the cost of the installation?

1.2 Delimitations

One delimitation in this study is to only consider existing buildings, not planned ones. The effects of the installation on the local electrical grid are not studied and already existing solar power systems are not considered when proposing possible locations for new solar power installations. _{Diversity of rooftop-materials or smaller aggravating obstacles on} rooftops are not considered. Another delimitation made in this study is that if some part of a building is protected due to historical or cultural values, the whole building is seen as such. The walls of a building are not considered as possible for module installation and an assumption is made that all modules implemented are fully functional. Finally, the

individual installation cost for every building will not be examined but rather an estimated mean cost for the whole installation.

1.3 Report outline

The report begins in section 2 with a background section where the goals of the municipality are presented as well as a description of how solar irradiation is measured. Thereafter a section about what constitutes a suitable building is presented and information about what to keep in mind when placing solar modules on rooftops or land areas. In section 3 the

methodology that is used in this study is presented as well as how the data was obtained and used. In section 4 the results of our findings are presented including the results from the sensitivity analysis. The report ends with a discussion in section 5 including the sensitivity analysis and sources of error, along with a short conclusion in section 6.

2 Background

This section presents relevant background information in order to investigate the research questions. In section 2.1 the municipality’s solar power goal is presented together with their preferences of how it should be achieved. In the next section, 2.2, different models that can be used to determine solar irradiation are introduced. The significance of the orientation of a building is explained in section 2.3 together with an explanation of albedo. The definition of

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what constitutes a suitable building is presented in section 2.4 and lastly, in section 2.5, different types of photovoltaics and their varying efficiency are presented together with information on how to install modules on rooftops and land areas.

2.1 Solar power milestone

Uppsala municipality has set goals in order to reduce greenhouse gas emissions and is aiming to reach these goals partly by expanding their use of renewable energy. Uppsala municipality aspires to have 30 MWp solar power by 2020 and 100 MWp solar power by 2030 (see _{Figure 1) [3].}

Figure 1. Illustration of goals (blue) for installed PV power in Uppsala municipality and actual installed power (yellow)[3].

Uppsala municipality has today 5 MWp installed solar power, which means it has yet to install 25 MWp until 2020 [3]. This can according to the municipality be achieved by installing modules on rooftops or if necessary by also installing a solar park [3]. Besides reaching the 30 MWp goal, the municipality have some preferences on how this goal should be reached. It would rather make installations on rooftops than setting up a solar park [5]. If possible, the municipality would also like the solar modules to have an even spread

throughout the city, be placed on the largest rooftop areas and be visible to the public [5].

2.2 Tools to measure solar irradiation

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2.2.1 Geographic Information System

Geographic Information System (GIS) is a system for capturing and presenting data relative to geographical locations. GIS makes it possible to combine and compare georeferenced data. For example, election results, landscapes and locations of different types of buildings [6].

2.2.2 Solar map

Solar maps are constructed to present the potential solar power generation on buildings in urban environments with the help of GIS. The solar map could potentially be combined with either map layers for instance showing buildings protected due to historical or cultural values. The maps serve the purpose to advise citizens of how and where they can install photovoltaics. Also, the map function as a tool for city planners in their work to increase solar power in the city [7].

Uppsala municipality has ordered a map containing the solar irradiation on all rooftops in the county, (see _{Figure 2). The solar map visualizes irradiation on rooftops and takes into} consideration shadows from chimneys, other buildings, vegetation etc [8].

Figure 2. Residential neighbourhood from Uppsala solar map showing irradiation. Red colour of the rooftop means good-, yellow ok- and blue not good irradiation. 2

2.2.3 Irradiation model

Irradiation on rooftop surfaces can also be computed through a program created by Dr David Lingfors [9]. With the help of Light Detecting And Ranging-data (LiDAR-data), the program categorizes spatial information about different buildings [10]. This program sample surface-characteristics of buildings, e.g. area of buildings, tilt of rooftops, irradiance on the

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rooftops and number of modules recommended to be installed on the rooftops [9]. The program could run LiDAR-data of various resolution. High-resolution data have typically around 6-8 measure points per square meter and low-resolution data around 0.5-1 measure points per square meter, but these values could vary [9].

The program simplifies each building polygon in the property map, from the swedish land survey [11], into rectangles by removing protrusions, (see _{Figure 3). Each structure consists} of five to eight facets and each facet represents a wall or rooftop segment of the building, (_{see Figure 3). For every facet, the program provides a grid of points called facet points, at} which the irradiation is calculated. The suitability of installing modules on a facet is determined from a chosen level of irradiation required, for example 900 kWh per m2_and

year. Where this is achieved, standard modules with a size of 1.6 m2_{are placed [9].}

Figure 3. Building that is simplified to a structure with six facets. The Facet points (blue) are situated along the facets. The LiDAR points (red) overlap the entire map area.

Around 60% out of 3970 studied buildings in Uppsala have rectangular shape and close to 80% have an area of the simplified (rectangular) footprint that is at least 80% of the original [9]. Residential buildings are commonly built in rectangular shapes, which buildings owned by the municipality more often are not.

2.3 Azimuth

When placing solar modules, the orientation towards the sun have to be taken into

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Figure 4. Illustration of a house with cardinal directions as well as an azimuth angle.

2.4 Albedo

The ratio of incident light that is reflected by a surface is referred to as the albedo of the surface [13]. Most natural, surfaces have an albedo of about 5 to 30% where exceptions may occur when snow covers the ground which increases the albedo [13]. Ground usually have an albedo of around 20% [14].

2.5 Definition of suitable buildings

In this section a definition of what is considered a suitable building is presented. This is important in order to recognize which buildings are suitable for placement of PV modules. A building is defined as suitable if the following constraints are met:

1. The building is owned by the municipality

2. The building does not have a rooftop with the colour red 3. The building is not protected due to historical values

To install solar modules on a rooftop in Sweden, a building permit is required. Building permits are handled by the planning commission which means that they approve or reject building permit applications [15]. Common reasons for rejection of a building permit application for solar module installations are either that the building has a rooftop with the colour red or is protected due to historical or cultural values [15].

2.5.1 Buildings with red rooftops

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and the colour stated in the building specification in reality do not always match [15]. For example, a building could have a black rooftop in the building specification but in reality have a red rooftop. In that case, a building permit to install solar power could be granted even though the rooftop in reality is red. The reason for building permit rejection is that an installation of a solar power system could damage the aesthetics of the house when black modules are installed on a red rooftop [15]. An alternative is to install red solar modules which would not change the aesthetics of the house as much. Red solar modules have both lower efficiency and are more expensive than black solar modules, which is why the municipality prefer to avoid red rooftops for solar power installations [3].

2.5.2 Buildings protected due to cultural and/or historical values

Buildings and environments with cultural and/or historical values are commonly protected by law. The protections are not always binding but serves as guidelines and support for future construction plans [16]. Two types of protections with legal status are k and q. k-marked protection gives directions of awareness and caution when changing or

maintaining a building or an environment [17]. When changes are about to be made around this area, specific characteristics must be preserved. This protection can be arranged for parts or subproperties of a building or an environment. q-marked protection includes features of areas or buildings that needs to be preserved [17]. Uppsala today has 69 buildings protected by the cultural act (KML) [18]. k- and q-marked buildings are in this report not considered as suitable for solar module installations.

2.6 Photovoltaics (PV)

Section 2.6.1 contains general information about solar modules as well as costs for different kinds of installations. In section 2.6.2 a system performance measure used in this study is presented.

2.6.1 Solar power modules and systems

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Table 1. Efficiency for crystalline-silicon modules [20-21] and thin-film modules[22].

Type of PV Efficiency (%)

Crystalline-silicon 15 - 25

Thin-film 15 - 17

Table 2. Prices for different types of systems [23].

Type of system Average price (SEK/Wp)

Ground-mounted PV park > 500kW 9.2

Roof-mounted commercial system 11.6 - 12.3 3

2.6.2 Energy per Rated Power (ERP)

A way to measure how well a photovoltaic system performs is Energy per Rated Power (ERP) which compares the energy yield of a system with peak power. Energy yield here represents the AC output of the system, which means that system losses in cables,

converters and shading are included [24]. In Sweden, the ERP for a well placed solar power system is about 1000 kWh/kWp [25].

2.6.3 Standard test conditions

Standard test conditions (STC) makes it possible to compare different types of PV modules between manufactures. STC tests different modules with the same parameters: solar cell temperature is set to 25 degrees Celsius, irradiance to 1000 W per m2_{and air mass}

(thickness of the atmosphere) to 1.5 [26].

2.7 Installations on tilted rooftops

Solar modules are normally mounted directly onto tilted rooftops. The recommendation for gabled rooftops is to place the solar modules on the rooftop side towards the south, (see

Figure 5)_{. If the building is placed with the gable towards the south, modules could}

preferrably be placed on both sides of the rooftop, both in east and west [27]. In Sweden, a rooftop with a tilt of around 40° directed towards the south gives the optimal production [27].

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Figure 5. Illustration of solar modules placed on a tilted rooftop facing south.

2.8 Installations on flat areas

Solar power installations on flat areas in Sweden require a tilt of the modules in order to optimize power production and to avoid accumulation of dirt and snow, (see _{Figure 6 a and}

b)_{. A module placed in the horizontal plane have about 20% less yield than an unshaded}

module with maximum yield orientation in Sweden [28].

Figure 6. a) Sketch illustrating solar modules in tilted rows. The system could be mounted either on flat rooftops or on the ground. b) Sketch illustrating solar modules in a) seen from the side with tilt 𝛾.

2.8.1 Optimal tilt and limit angle

Mounting solar modules in tilted rows will result in internal shading, meaning that when the sun is at a low position, the first row of modules will cast a shading onto the second row and so on. To minimize these losses due to internal shading, rules of thumb for mounting solar modules are often used, see _{Table 3 below [28]. These rules of thumb state values of angles} used in the dimensioning of the installation. The limit angle, 𝜽, represents the lowest angle the sun can have without causing any internal shading on the modules, (see _{Figure 7).}

Figure 7. Illustrating sketch over the shading each row of modules result in. The limit angle, 𝜽, is the minimal

angle of the sun which do not result in internal shading and the tilt angle, 𝛾 is the angle of which the modules

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Different rules of thumb are used for rooftop- and solar park installations. Because of the limited space, available area is the crucial factor of a rooftop installation. This means that losses can be allowed to be bigger if the occupied area is smaller [28]. Solar park

installations often result in lower losses but a greater occupied area, (see values for rules of thumb in _{Table 3 [28]).}

Table 3. Rules of thumb for angles used for installations on flat rooftops and solar park. Limit angle is the lowest angle the sun can have without causing any internal shading on the modules and tilt angle is the tilt of the modules. The losses are based on the shading of the modules when they are placed in rows [28].

crystalline - silicon thin - film

Rules of thumb Flat rooftops Solar park Flat rooftops Solar park Limit angle, 𝜽 13° 10° 25° 15° Tilt angle, γ 15° 25° 20° 25°

Maximum annual losses 10% 5% 10% 5%

2.8.2 Flat rooftops

Modules installed on flat rooftops are ordinarily placed along the side oriented towards the south. Because of the relatively easy module installations on flat rooftops, this alternative is often considered more economically favorable than mounting solar modules on tilted rooftops. Another advantage of installing solar modules on a flat rooftop is that the

mounting system is adjustable and can therefore be optimized to get higher power output. A rooftop is often considered flat when the tilt is equal or lesser than 5 degrees [27].

2.8.3 Solar park

Uppsala municipality are investigating the possibility of installing a solar park. Uppsala is growing rapidly and all land area close to the city is therefore of high value [3]. There is also a possibility that a solar park has to occupy an area of significant size. Furthermore, high buildings, trees or other vegetation may cast shadows upon the area which makes it less suitable for a solar park installation [3].

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There are two main ways in which this is done: fixed-angle system and sun-tracking-system, which may be either single- or dual-axis [29].

Fixed-angle structures are tilted to maximize the irradiation. The system has fixed tilt- and azimuth angle which are decided before installation. The benefits of a fixed-angle system are that they are not as complex, often cheaper and require lower maintenance than sun-tracking systems [20]. An example of a fixed angle system is illustrated below, (see

Figure 8_).

Figure 8. Illustration of fixed angle systems.

A sun-tracking system traces the sun, like a sunflower, across the sky; either in one

dimension by changing tilt- or azimuth angle, or in two dimensions by changing both, (see an example in _{Figure 9). One of the reasons to install a sun-tracking system is the increase} of irradiation on the modules. A sun-tracking system provides up to 27% higher annual energy output than fixed-angle systems for changes in one dimension and up to 45% higher for changes in two dimensions [29]. A sun-tracking system has higher costs than a

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Figure 9. Illustration of a sun-tracking system.

3 Methodology and data

The research questions in this study were investigated through a number of interviews, calculations, programming, literature studies and guidance from the supervisor. Kristina Starborg, head of solar power development at Uppsala municipality, has been interviewed to provide an understanding of how and why Uppsala municipality have set their climate goals. The municipality has through Starborg provided crucial data (see section 3.2). Supervisor David Lingfors has throughout the project been a helping hand.

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Figure 10. Schematic sketch of the methodology which illustrate the four steps that will be taken to reach the purpose of the study. The coloured boxes illustrate the values that will be changed in the sensitivity analysis.

Buildings suitable for solar power installations were identified through creation and usage of scripts in Matlab. One type of geographical information system software is QGIS, which were used to visualize the results as layers. Five QGIS layers were created containing real estates owned by Uppsala municipality, buildings owned by Uppsala municipality, buildings with red rooftops, all flat rooftops suitable for installations and potential placement of

module installations.

Besides the fact that installations are only proposed on suitable buildings, a further

limitation was made to only propose installations on rooftops with at least 40 m2_irradiation

greater than 900 kWh per m2_{and year; the configuration in which the modules are placed}

were however not considered. Besides losses stated by the rules of thumbs, (see section 2.8.1), system losses including losses in cables and converters were assumed to be 10% [30]. Crystalline-silicon modules with an efficiency of 15% were assumed in this study, this since crystalline-silicon modules are dominant on the market [31].

The installed power of the system was calculated with the STC method, which do not

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internal shading, losses due to shading from close by vegetation and buildings as well as the azimuth of the buildings and albedo of the panels. Temperature dependence of the modules was however overlooked in this calculation due to the limited time of this study, a

delimitation which could result in a slightly higher calculated annual energy yield than the system would generate in reality. The calculation was made through a script simulating solar irradiance data from the solar resource database _{Meteonorm for Stockholm from 2014,} which lies relatively close geographically and is therefore assumed to be representative for Uppsala [9].

Since no specific area was examined in order to install a solar park, an assumption had to be made in order to decide the geometry of the park. In this study, the park was assumed to have an equal amount of modules widthwise as lengthwise. The type of mounting system was decided as a fixed-angle system, this since a previous study had made the conclusion that sun-tracking systems are to this day not economically favourable (see section 2.8.3), even though they provide higher power output.

The total cost of the system was decided through standard values presented in _National

survey report of PV power applications in Sweden_{which takes both installation- and}

module costs into account. Since the prices differ between different sizes of rooftop installations, a mean value of the price for installations of approximately 15 kW and approximately 100kW was calculated, the cost of the park is regarding ground-mounted solar parks larger than 500 kW [24].

A sensitivity analysis was conducted to examine how different variables would affect the final result. In this report the type of module is changed which in turn affect cost of module, rules of thumb and efficiency.

3.1 Solar power calculations

In this section equations used in this study are presented. Section 3.1.1 describes how the azimuth angle and the length and width of a building is calculated. In section 3.1.2 equations formulated to calculate how many modules that can be mounted on a flat rooftop or land area are presented. Lastly, in section 3.1.3 equations to calculate the installed power of the system are defined.

3.1.1 Calculation of azimuth

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Figure 11. Illustration of a building seen from above to explain the calculations of azimuth (α), the dark grey dots represent the positions of the building’s coordinates.

To calculate the azimuth angle of a building, equations (1) - (3) are used. The height _{h of the} triangle in _{Figure 11 is calculated as;}

y y

h = ₂ − ₁ , (1)

where y₂ is the latitude coordinate of one of the edges of the building, (see _{Figure 11), and} y₁ is the latitude coordinate of the edge of the building which faces south the most. The length _{l of the triangle is calculated as;}

, x x

l = ₂ − ₁ (2)

where x₂ is the longitude coordinate corresponding to y₂and x₁is the longitude coordinate corresponding to y₁. The azimuth angle is calculated as;α

,

arctan( )

α = h _l ₍₃₎

where _{h is the height of the triangle in Figure 11 calculated in equation (1) and l is the} length of the same triangle calculated in equation (2). The length and width of the building are both calculated with following equation;

,

s =

√

h 2+ l2 (4)

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3.1.2 Solar modules on flat rooftops

The potential number of solar modules on a flat rooftop is derived in this section. As seen in

Figure 12, _{the width of the solar modules is W}₁ and the length of the flat area is L_R.

Figure 12. Illustration of two rows of solar modules including their internal shading. The modules fully covers the length of the roof and no more rows can be installed, situation 1.

The length occupied by one solar module without shading is calculated with following equation;

,

cos(γ)

L₁ = W₁· (5)

where W₁is the width of a solar module and is the tilt angle of the modules. The lengthγ of the internal shading from a module is calculated as;

,

os(θ) W os(θ)

L₂ = c · ₂ = c · sin(γ)· W_sin(θ) 1 ₍₆₎

whereW₁is the width of a solar module, is the tilt angle of the module and is the limitγ θ angle. Total length occupied by a solar module and the internal shading is;

,

( cos(γ) )

L = L₁+ L₂ = W₁ + cos(θ)· sin(γ)_sin(θ) (7)

where L₁ and L₂ are described in equations (5) and (6). The amount of module rows

lengthwise when shading of the solar modules extends to the end of the rooftop is calculated as;

,

floor( )

Nrow = _{L +L}LR

1 2 (8)

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final row of modules could fit on the rooftop, (see _{Figure 13). The part of the the roof that is} not shaded ( L ₃) is derived from the equation below;

,

(L )

L₃ = L_R− N_row ₁ + L₂ (9) where _N_row is derived from equation (8), L_Ris the length of the rooftop and L₁ and L₂ are described in equations (5) and (6).

Figure 13. Illustration of two rows with its internal shading which not fully cover the length LR. If L3≥ L1 one

more row of modules could be placed on the rooftop.

The amount of rows that can fit the rooftop will then be; if L

Nrow + 1 3 ≥ L1

otherwise

N_row

where L₁is the length needed to install a module and L ₃is the space left on the rooftop as seen in _{Figure 11.}

3.1.3 Calculations of installed power output

To calculate the installed power output from a PV module with the STC method, the efficiency and area of the module have to be known along with the irradiation level at standard test conditions. The installed power output is calculated from;

,

P_installed= η_modul · A · I (10)

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3.1.4 Energy per Rated Power

The Energy per Rated Power (ERP) of the system can be calculated from; , RP E = _P installed E_DC· η_System (11) where ηsystem is the system efficiency, _EDC is the DC energy output and Pinstalledis the

installed capacity of the system.

3.2 Data

Data in this study were collected primarily from Uppsala municipality which provided a list of municipality owned real estates and also a shapefile with buildings in Uppsala protected due to historical and cultural values. Shapefiles of buildings and real estate polygons in Uppsala were collected from Lantmäteriet. Information about red rooftops were retrieved manually using Google Earth in QGIS. Irradiation data from the STRÅNG [32] model for 2014 was used in the _{Irradiation model (see section 2.2.3).}

3.2.1 Municipality owned buildings

Real estate ID numbers provided by the municipality which matched with real estate ID numbers in the Lantmäteriet data set. All buildings located within the borders of a municipality owned real estate could thereafter be categorized as a municipality owned building.

3.2.2 Red rooftops

Due to the limited time given, the process of_{deciding if a building has a red rooftop or not} had to be simplified. The proper way to do this is to investigate every building individually using the building specification. In this study this was determined by usage of Google Earth. Google Earth was opened in QGIS and by manually evaluating the colour of each

municipality owned rooftop, a layer visualizing buildings with red rooftops was created.

3.2.3 Buildings protected due to historical and/or cultural values

Information about k- and q-marked buildings in Uppsala was provided by the municipality. This layer includes all buildings protected due to historical and cultural values in Uppsala, not only municipality-owned.

3.2.4 Suggestions for module installation on tilted rooftops

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low-resolution LiDAR-data was used (0.5-1 points per square meter) as input to the Irradiation model.

3.2.5 Flat rooftops

By using the same method as in the section above, suggestions for module installation on flat rooftops were decided. This layer contains georeferenced flat rooftop areas with annual irradiation as the main attribute. The amount of modules for a suitable flat rooftop were determined by area and calculations with equations described in section 3.1.2. These rooftops are assumed to be without shading from close vegetation and/or buildings, which may not always be true.

3.3 Sensitivity analysis

A sensitivity analysis was made to investigate how one or several different parameters would affect the final result. The parameter investigated in this study is _{type of module, from} the more common crystalline-silicon modules to thin-film modules. Changing the type of module also affect the parameters cell efficiency, and rules of thumb for flat area

installations. Because efficiency can vary significantly between the same type of modules, this parameter was also changed individually, keeping all other parameters fixed.

4 Results

This section presents the results of the study. Firstly, section 4.1 presents examples of buildings suitable for PV installation. Thereafter, in section 4.2, the solar power potential of municipality owned rooftops is shown together with figures illustrating how the installations could be made. In section 4.3, the dimensions and power output of a solar park is presented and a cost evaluation is presented in section 4.4. Section 4.5 describes the results from the sensitivity analysis and_{in section 4.6 the ERP of the system is presented.}

4.1 Suitable buildings

Suitable buildings for solar power installations have been determined and illustrated as a layer in QGIS. Municipality owned buildings are illustrated below, (see _{Figure 14 and}

Figure 15_{). The buildings not suitable for solar power installations, buildings protected due}

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Figure 14. Map in QGIS illustrating municipality owned buildings possible for PV installations in blue, and municipality owned buildings with red rooftops illustrated in red. This means that only the building illustrated

with blue are suitable in this area.

Figure 15. Map illustrating suitable buildings. Buildings owned by the municipality shown in blue and buildings protected due to historical and/or cultural values shown with dots. This means that only blue

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4.2 Solar power of rooftop installations

The solar power potential of suitable rooftops is derived from simulations in Matlab. The result shows that 24.1 MWp could be installed on the municipality owned rooftops which means that a solar park is required to reach the goal of 30 MWp to 2020. These numbers are calculated for a crystalline-silicon module installation with a module efficiency of 15%. The suitable locations for rooftop based modules are spread throughout Uppsala, which is in line with the municipality’s preferences on how the installations should be made. The spread throughout the city also provides visibility for the public in different areas. The positions of these installations are illustrated in a GIS layer (see _{Figure 16). Exact positions for flat} rooftop installations were due to the limited time given not illustrated with a layer, instead the flat rooftops suitable for installation were marked, (see _{Figure 17).}

Figure 16. The potential placements of solar module installation on tilted rooftops. Buildings where no solar

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Figure 17. Illustration of the potential placement of solar module installations on flat rooftops. In the map, the

flat rooftops suitable for installation are illustrated with a blue lining around the edges of the house.

4.3 Solar park dimensions and power output

Since the municipality’s goal of installing an additional 25 MWp cannot be reached solely through rooftop installations, an investigation of a solar park has been made, see _{Table 4.} The size of the solar park needs to be at least 2.01 hectare with the installed power of 0.893 MWp to complement the modules installed on rooftops.

Table 4. Results linked to the dimensioning of a solar park. Assumptions have been made that the modules of the park are oriented toward the south and that the same amount of modules are put width- and lengthwise.

Result Value

Solar power (MWp) 0.893

Type of module crystalline-silicon

Module efficiency (%) 15

Area of park (ha) 2.01

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4.4 Cost of installation

The cost of the implementation consider both installations on rooftops and a solar park. It takes both installation and module costs into account. The price for the rooftop installation is based on a mean value and for the park typical costs are assumed to ground-mounted solar parks greater than 500 kW (see section 3). The total cost for the installation is 296 MSEK , 4

where the majority of the investment goes to rooftop installations.

Table 5. Costs for installing a PV system of crystalline-silicon modules with an efficiency of 15% on both rooftops and in a solar park.

Cost of installations on rooftops (MSEK) 288

Cost of installation of solar park (MSEK) 8.22

Total cost (MSEK) 296

4.5 Sensitivity analysis

The results of the sensitivity analysis are presented in _{Table 6 and is conducted through} changing the parameter _{type of module, which in turn affect the parameters efficiency, limit} angle and tilt angle. Since the efficiency vary significantly for within the same type of module, this parameter is also changed separately. The lower limit of efficiency is the average value for the specific type of module and the higher limit represents a value that has been successfully tested outside laboratories.

The sensitivity analysis indicates that changing PV technology affects the installed power on rooftops and also the demanded size for a solar park due to specific construction

characteristics and span of efficiency levels. For crystalline-silicon modules, an efficiency of 15.6% would mean that a solar park is no longer required, the same value for thin-film modules is 14.6%. This means that in order to reach the goal of 30 MWp a solar park is only required in the case of crystalline-silicon modules with an efficiency of 15% for the cases tested in the sensitivity analysis. This also shows that thin-film modules demands a smaller installation area to achieve the same potential power output at the same efficiency level, because the rows can be put closer together. It should be mentioned that crystalline-silicon modules usually have higher efficiency levels than thin-film modules. Because of this, crystalline-silicon modules have the potential to be more area efficient than thin-film_.

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Modules with higher efficiency are more expensive but demand a smaller total area for installations. This could be a preferable alternative since area for installations is a valuable resource, but without an estimation of exactly how valuable the land area is, this question will be left unanswered.

Table 6. The table presents crystalline-silicon and thin-film modules and its respective results for different efficiency levels (see section 2.5).

crystalline-silicon thin-film

Efficiency (%) 15 25 15 17

Cost Park (MSEK) 8.22 0.00 0.00 0.00

Cost Rooftop (MSEK) 288 480 306 347

Total cost (MSEK) 296 480 306 347

Area Park (ha) 2.01 0.00 0.00 0.00

Installed power Rooftop (MWp) 24.1 40.2 25.6 29.0

Installed power Park (MWp) 0.893 0.00 0.00 0.00

Total amount of modules (tpcs ) 5 ₁₀₄ ₁₀₀ ₁₀₇ ₁₀₇

4.6 Energy per Rated Power

The _{Energy per Rated Power is the ratio between energy yield of the system and the} installed power and is a measure of how well a system is performing. The results of this analysis are presented in _{Table 7. The ERP ratio of the total installation is lower than} expected, since the ERP for a well placed solar power system in Sweden typically is around 1000 kWh/kWp. This means that the installations (especially on the tilted rooftops since this ERP ratio is particularly low), do not generate as much energy as a typical solar power system in Sweden when comparing with the amount of installed power. This could indicate that it would be wise to choose especially the_{tilted rooftops more carefully than to make all} the installations proposed in this study. To reach the goal of 30 MWp installed until 2030 a larger solar park would be needed in this case.

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Table 7. Results of energy yield and ERP.

ERP tilted rooftops (kWh/kWp) 860

ERP flat rooftops (kWh/kWp) 994

ERP solar park (kWh/kWp) 992

ERP total installation (kWh/kWp) 902

Total energy yield (GWh/year) 22.0

5 Discussion

To reach Uppsala municipality’s solar energy goal, investments in both rooftop-installed modules and a solar park are required when assuming standard modules. The aim to install 30 MWp solar power until 2020 demands installations on all suitable buildings owned by the municipality with more than 40 m2_{irradiation level of at least 900 kWh per m}2_{and year.}

The municipality’s preferences to arrange solar power installations on rooftops in visible locations and with an even distribution across Uppsala, can therefore not be considered when proposing rooftop installations. A notion should be made that this still could be seen as fulfilled since installations are proposed on all municipality owned buildings that meets the installation requirements.

A solar park is needed in order for the municipality to reach their goal. The size of 10 ha is required in order to accomplish this, which correspond to around 19 regular-sized soccer fields. Land areas of this size will be visible for the public if placed close to areas where people are passing by frequently. For instance, the solar park could be placed close by European highway 4 (E4) where many people travel daily. This will further satisfy the municipality's wishes to make the public awareness of investments made in solar energy. If a solar power system would be installed as suggested in this study it would probably not only contribute significantly to the solar power locally but also in a national perspective [24]. The solar park Solsidan_{in Varberg is currently the largest solar park in Sweden and} has an installed power of 2.70 MWp and installation cost of 24.0 MSEK [33]. The cost of Solsidan was 8.89 SEK per W whereas in this study 9.21 SEK per W is assumed, (see _Table

2_{) [33]. Due to Solsidans size, the installation cost lies 20% lower than the IEA statistics in}

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When comparing with other solar parks internationally, larger installations have already been completed successfully. In Denmark, a solar park of 61 MWp has been installed, which today is the largest park in Scandinavia [35]. The park covers over 80 hectares, consists of 248 730 solar modules and are estimated to supply up to 30 000 private households with electricity [35]. In perspective, Uppsala municipality would need less than half of this amount (104 000 on both rooftops and in the solar park) to reach their goal. However, there is another aspect of importance to mention, merely how this solar park would help the municipality to achieve the greater goal to lower emissions. The solar park would require land area that could be used for other purposes, for example growing crops or building apartments for the rapidly expanding city. One could argue that it would be better to use solar modules with high efficiency even though they are more expensive, this to save land area that could be used for other purposes.

Large investments are needed for both the rooftop- and the solar park installations, The budget of the municipality is 782 MSEK for 2018 of which 5% are devoted to technological and environmental development [36]. This corresponds to approximately 39.1 MSEK the year 2018. Since the calculated cost of this installation is 295 MSEK it would be difficult for the municipality to manage this investment by themselves. Important to remember is that the municipality does not plan to achieve this goal only by own means. Depending on solar power investments by local private and public actors in Uppsala, the actions of the

municipality could be adapted thereafter.

5.1 Sources of error

In this section sources of errors are discussed to provide a greater understanding of how this study is conducted and how it could be improved.

5.1.1 Deciding municipality owned buildings in QGIS

When deciding if a building is owned by the municipality or not, there is a source of error that has to be mentioned and taken into consideration. The script created investigates if all coordinates of a building are located inside, or on the edge of a municipality owned real estate. A problem arose when coordinates of a building partly were located inside, and partly outside a municipality owned real estate. In these cases, manual decisions were made to decide if a building could be seen as inside the municipality owned real estate. This factor could mean that buildings which in reality are municipality owned were not marked as such in the layer and therefore not investigated as suitable, and vice versa. The were

approximately 30 out of 3720 buildings that were hard to decide on.

5.1.2 Red rooftop identification

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buildings has a red rooftop or not, they do so by checking the rooftop colour in the building specification. This means that the shapefile containing buildings with red rooftops have a margin of error and it is hard to determine the impact of this error on the results. The selection depends on how the colour of the rooftops are perceived in Google Earth. In other words, a building which in reality have a black rooftop but red rooftop-colour stated in the building specification, is not categorized as having a red rooftop in the shapefile but would be by the planning committee. However, if the building has a red rooftop in reality but not this colour stated in the building specification, the building is viewed as having a red rooftop in the shapefile but not by the planning committee. Also, to decide the colour of a rooftop through Google Earth is sometimes difficult due to shading and dust covering the rooftop, (see _{Figure 18).}

Figure 18. Illustration that shows buildings through Google Earth. Some rooftops have clearly a red shade, for instance, the one illustrated in the red box. Others are harder to determine the color of, for example, the

buildings illustrated with yellow boxes.

5.1.3 Low resolution LiDAR data

The calculations of this report are based on low resolution LiDAR data with 0.5-1 measurement points per square meter. This means that the outcome could become more accurate by using high resolution data. For instance, this would increase the identification accuracy of different building types and thereby the irradiation would be more accurate. Using high-resolution LiDAR data would be preferable demands computational

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5.1.4 Losses in removed protrusions

When simplifying the buildings to rectangular shapes, sometimes a significant part of the building is removed. This often happens when the largest simplified rectangular part does not constitute the majority of the building, (see _{Figure 19).}

Figure 19. Example of a building of which, the largest simplified rectangle (grey) do not constitute the majority of the building. Therefore, the area losses are high. The dashed rectangles represent protrusions that

have been removed during the simplification.

This approach results in rooftop-area losses which could have been suitable locations for solar modules. Also, a larger amount of unconventional buildings belong to the municipality in comparison to the residential buildings. However, removed protrusions are often areas where installation of solar modules would not be suitable due to their limited amount of space or because of their obscure geometry. This implies that the losses in potential area for module-installation due to removed protrusions might not be as high as presented in _Figure

19_above.

5.1.5 Flat rooftop irradiation

A flat rooftop were considered suitable if at least one module placed on it has an irradiation greater than 900 kWh per m2_{and year and then assuming that the whole rooftop has the}

same irradiation. This is a potential source of error due to the fact that an unknown section of the flat rooftops could have a lower irradiation than 900 kWh per m2_{per year because of}

shading. This assumption results in an overestimation of suitable areas were solar modules could be installed, and by extension, an overestimation of the total installed PV capacity on the rooftops.

5.1.6 Cost approximation

Cost calculations are made with values from the _{National survey report of PV power}

applications in Sweden _{where the values are presented in SEK/Wp. This means that the cost}

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5.2 A future outlook

The municipality is constantly working towards building a city where climate aspects are of high value. One of these aspects is to increase the potential for renewable energy in order to decrease the amount of greenhouse gas emissions. To accomplish this the municipality wants to expand investments in solar energy by continuing to collaborate with both private companies and public actors to invest in solar energy. This is essential in the pursuance of their goals set for 2020 and 2030 given the limited rooftop area for solar power within the municipalities own building stock as identified in this study. The municipality is more willing to accept new building proposals if the building is designed to have implementation of solar energy of some kind. This could mean that future buildings will be designed to help the municipality reach their goal for solar energy [3].

The market of solar energy is rapidly changing. Worldwide investments drives the technology forward which makes the solar modules cheaper. The efficiency of the solar modules is also expected to improve in the coming years due to the technical development and the amount of research taking place today [37]. Therefore, the municipality´s efforts in the area of solar energy may prove to be more favourable than expected in coming years. An increase in efficiency affects both the installation costs and the power output from it (see section 4.5). As mentioned before, if the efficiency of the solar modules with PV technology crystalline-silicon is 15.6%, a solar park is not needed to reach the municipality´s milestone. When using thin-film modules, a larger amount of modules could fit in a specific area.

Crystalline-silicon modules often have a higher efficiency which in turn could decrease the need of installation area. Depending on the circumstances of the implementation, these factors should be regarded. In order to be able to not only reach the goal of 2020 but also 2030, further investigations are required to decide which module type that is most suitable for the installations.

By implementing these installations Uppsala municipality might set an example for both local public, private actors and other municipalities. It would also take a step in the right direction towards the goal of being the leading municipality in Sweden in terms of installed solar power capacity.

6 Conclusion

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estimated to be 296 MSEK. Rooftop installations will in total cost 288 MSEK. The rest of the cost is linked to the solar park installation (8.22 MSEK).

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References

[1] NASA, (2018), _{The consequences of climate change, available online:} https://climate.nasa.gov/effects/ (2018-05-17).

[2] Sweden, (2018), _{Sweden tackles climate change, available online:} https://sweden.se/nature/sweden-tackles-climate-change/ (2018-05-17).

[3] Starborg, K., head of solar power department at Uppsala municipality, Interview 2018-03-27.

[4] Uppsala kommun, (2015), _{Miljö- och klimatprogram 2014-2023, available online:} https://www.uppsala.se/contentassets/5d36faebce83404888c3a4677bad5584/Miljo-och-klim atprogram-2014-2023.pdf (2018-05-17).

[5] Starborg, K., head of solar power department at Uppsala municipality, Mail correspondence, 2018-04-04.

[6] National Geographic, (2018), _{GIS(geographic information system), available online:} https://www.nationalgeographic.org/encyclopedia/geographic-information-system-gis/ (2018-05-22).

[7] Kanters, J., Kjellsson, E., Wall, M., (2013), _{The solar map as a knowledge base for solar}

energy use,_{available online:}

https://www.sciencedirect.com/science/article/pii/S1876610214004421 (2018-05-22). [8] Uppsala kommun, (2018), _{Installera solceller, available online:}

https://www.uppsala.se/boende-och-trafik/din-bostad/installera-solceller/ (2018-05-17). [9] Lingfors, D., (2017), _{Solar variability assessment in the built environment - model}

development and application to grid integration.,_{Kph Trycksaksbolaget AB, Uppsala.}

[10] ARCMAP, (2018), _{What is lidar data?, available online:}

http://desktop.arcgis.com/en/arcmap/10.3/manage-data/las-dataset/what-is-lidar-data-.htm (2018-05-17).

[11] Lantmäteriet, (2017), _{GSD-property map, vector, available online:}

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[12] PVEDUCATION.ORG, Bowden, S., Honsberg, C., (2018), _{Azimuth angle, available} online: http://pveducation.org/pvcdrom/properties-of-sunlight/azimuth-angle (2018-05-17). [13] SMHI, (2017), _{Solstrålning, available online:}

https://www.smhi.se/kunskapsbanken/meteorologi/solstralning-1.4186 (2018-05-25). [14] Widén, J., (2013), _{Solar radiation computer lab instructions, Uppsala University.} [15] Starborg, K., head of solar power department at Uppsala municipality, Mail correspondence, 2018-04-18.

[16] Länsstyrelsen Uppsala län, (2018), _{Vad är ett byggnadsminne?, available online:} http://www.lansstyrelsen.se/uppsala/Sv/samhallsplanering-och-kulturmiljo/byggnadsvard/va d-ar-ett-byggnadsminne/Pages/default.aspx (2018-05-17).

[17] Ängelholms kommun, (2018), _{q och k märkning, available online:}

https://www.engelholm.se/Bygga-bo-miljo/byggande-och-lantmateri/Bevarandefragor/q-och -k-markning/_{/ (2018-05-17).}

[18] Länsstyrelsen Uppsala län, (2018), _{Byggnadsminnen i Uppsala län, available online:} http://www.lansstyrelsen.se/uppsala/Sv/samhallsplanering-och-kulturmiljo/byggnadsvard/b m/Pages/default.aspx (2018-05-17).

(2018-05-17).

[19] International finance corporation, (2015), _{Utility-scale solar photovoltaic power plants,} available online:

https://www.ifc.org/wps/wcm/connect/f05d3e00498e0841bb6fbbe54d141794/IFC+Solar+R eport_Web+_08+05.pdf?MOD=AJPERES (2018-05-21).

[20] Energimyndigheten (2018), _{Solceller, available online:}

http://www.energimyndigheten.se/fornybart/solenergi/solceller/ (2018-05-17).

[21] Harnesk, T., (2015), _{Dramatisk ökning av verkningsgrad hos solceller, available} online:

https://www.nyteknik.se/energi/dramatisk-okning-av-verkningsgrad-hos-solceller-6395849 (2018-05-17).

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[23] Lindahl, J., (2016), _{National survey report of PV power applications in sweden,} available online:

http://www.energimyndigheten.se/globalassets/fornybart/solenergi/national_survey_report_ of_pv_power_applications_in_sweden_-_2016.pdf (2018-05-17).

[24] Green rhino energy, (2018), _{Energy yield and performace ratio of photovoltaics}

systems,_{available online:}

http://www.greenrhinoenergy.com/solar/technologies/pv_energy_yield.php (2018-05-24) [25] Lingfors, D., Postdoc at the Department of Engineering Sciences at Uppsala University, Mail correspondence, 2018-05-24.

[26] Sino voltaics, (2011), _{Standard Test Conditions(STC): definition and problems,} available online:

http://sinovoltaics.com/learning-center/quality/standard-test-conditions-stc-definition-and-pr oblems/ (2018-05-22).

[27] Malmsten, J., (2015), _{Solceller på tak., available online:}

http://belok.se/download/Solceller_pa_tak_handbok.pdf (2018-05-17).

[28] Näsvall, D., (2013), _{Development of a model for physical and economical optimization}

of distributed PV systems.,_{available online:}

http://www.diva-portal.org/smash/get/diva2:632679/FULLTEXT01.pdf (2018-05-17). [29] Stridh, B., (2016), _{Utvärdering av Sveriges första MW-solcellspark., available online:} http://www.mdh.se/polopoly_fs/1.84979!/Menu/general/column-content/attachment/Utvard ering%20av%20Sveriges%20forsta%20MW-solcellspark%20rev3%2020160126.pdf [30] Stockholm stad, (2017), _{Stockholms solkarta, available online:}

http://www.stockholm.se/ByggBo/Leva-Miljovanligt/Stockholms-solkarta/ (2018-05-23). [31] Energy and efficiency & renewable energy, (2018), _{Crystalline silicon photovoltaics}

research,_{available online:}

https://www.energy.gov/eere/solar/crystalline-silicon-photovoltaics-research (2018-05-23). [32] STRÅNG, (2017), _{A mesoscale model for solar radiation, available online:}

http://strang.smhi.se/ (2018-05-23).

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[34] Varberg Energi. (2018), _{Solsidan, available online:}

http://www.varbergenergi.se/om-oss/var-verksamhet/sol/solsidan/ (2018-05-24).

[35] WIRSOL, (2018), _{Approximately 61-MegaWatt solar park the foundation for further}

projects in Denmark, _{available online:}

https://wirsol.com/en/wirsol-opens-largest-solar-park-in-scandinavia/ (2018-05-21). [36] Uppsala kommun, (2017), _{Mål och budget 2018-2020, available online:}

https://www.uppsala.se/organisation-och-styrning/publikationer/mal-och-budget-2018-2020/ mal-och-budget-2018-2020/#investeringar (2018-05-21).

[37] Energysage, 2018, _{How solar panel cost and efficiency have changed over time,}

available online:_{https://news.energysage.com/solar-panel-efficiency-cost-over-time/}

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Attachment

Matlab Scripts

%%%%%%%%%%%% Real estates owned by the municipality %%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %

% Script to transfer all real estates owned by the municipality from an % excel file to a script handable by QGIS

%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% Collect real estate data from Excel file provided by the municipality

realEstateTxt = xlsread('Bra-tak-solenergi.xlsx', 'alla kommunala byggnader','A2:A3160');

% Erase double real estate data in following for loop realEstateWOdoubles = []; i = 1; for l = 1:length(realEstateTxt) if l+1 > length(realEstateTxt)

if realEstateWOdoubles(i-1) == realEstateTxt(l) break else realEstateWOdoubles(i) = realEstateTxt(l); break end end

if realEstateTxt(l+1) == realEstateTxt(l) else realEstateWOdoubles(i) = realEstateTxt(l); i = 1+i; end end

% Real estate data from SLU containing all real estates in Uppsala

allRealEstate = shaperead('ai_get.shp');

% Shapefile the length of the number of real estates owned by the % municipality

muniOwnedRealEstate = allRealEstate(1:length(realEstateWOdoubles));

% Shapefile with real estates owned by the municipality created in for loop % below

for i = 1:length(muniOwnedRealEstate) for j = 1:length(allRealEstate)

if allRealEstate(j).FNR_FDS == num2str(realEstateWOdoubles(i),'%09.f') muniOwnedRealEstate(i) = allRealEstate(j);

break

end

end end

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% Script to transfer all real estates owned by the municipality that have

% total more than 40 m^2 rooftop area from an excel file to a script handable by & % QGIS %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Collect building data from Excel file provided by the municipality

realEstateFromExcel = xlsread('Bra-tak-solenergi.xlsx', 'Kommunala byggnader sol','A2:D336');

% Collect real estate data from SLU containing all real estates in Uppsala

allRealEstates = shaperead('ay_get.shp');

% Shapefile the length of the number of real estates owned by the % municipality muniRealEstate = allRealEstates(1:length(realEstateFromExcel)); counter = 1; for i = 1:length(realEstateFromExcel) for j = 1:length(allRealEstates)

if allRealEstates(j).FNR_FDS == num2str(realEstateFromExcel(i),'%09.f') muniRealEstate(k) = allRealEstates(j); counter = counter + 1; end end end shapewrite(muniRealEstate, 'realEstatesOwnedByMunicipalityPolygonlayer.shp')

%%%%%%%%%%%%%%%%% Buildings owned by the municipality %%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %

% Script to determine what buildings are owned by the municipality %

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

% Collect data about buildings from SLU containing all buildings in Uppsala

allBuildings = shaperead('by_get.shp');

% Collect data about what real estates are owned by the municipality

muniRealEstate = shaperead('realEstatesOwnedByMunicipalityPolygonlayer.shp'); muniBuildings = allBuildings;

% See what buildins are situalted inside of the real estate polygones % owned by municipality k = 1; for i = 1:length(muniRealEstate) i for j = 1:length(allBuildings) in = inpolygon(allBuildings(j).X(1:end-1),allBuildings(j).Y(1:end-1),muniRealEstate(i).X(1:end-1),muniRealEstate(i ).Y(1:end-1)); if in muniBuildings(k) = allBuildings(j); k = k+1; end end end muniBuildings = muniBuildings(1:k-1);

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%%%%%%% Connect attributes to buildings owned by the municipality %%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %

% Script to connect buildings owned by the municipality to the attributes % area, red rooftop and memorial protected

% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% clear all;

% Collect data about buildings owned by the municipality % Collect data about buildings that are memorial protected % Collect data about buildings with red rooftops

muniBuildings = shaperead('area_layer.shp');

memorialProtectedBuildings = shaperead('tillfixade_byggnader1.shp'); redRooftops = shaperead('red_roofs_Uppsala-1.shp');

% Four different lists are med in the following three loops: % objectIdList: all building's object id:s

% areaList: all building's areas

% redRoofList: a list consisting of zeros (if the building in question does % not have a red roof) or ones (if the building in question does have a red % roof)

% memorialProtectedList: a list consisting of zeros (if the building in % question is not memorialprotected) or ones (if the building in question % is memorialprotected) objectIdList = []; areaList = []; redRooftopList = []; memorialProtectedList = []; counter = 0; for i = 1:length(muniBuildings) objectIdList{i} = {muniBuildings(i).OBJEKT_ID}; areaList(i) = muniBuildings(i).area; end for i = 1:length(muniBuildings) for j = 1:length(redRooftops)

if redRooftops(j).OBJEKT_ID == muniBuildings(i).OBJEKT_ID counter = 1; end end if counter == 0 redRooftopList(i) = 0; else redRooftopList(i) = 1; end counter = 0; end for i = 1:length(muniBuildings) for j = 1:length(memorialProtectedBuildings)