Project Report of Grid Connected Rooftop Solar PV Power Plant at East Calcutta Girls College, Kolkata Total Capacity: 25kWp

Transcription

1 Project Report of Grid Connected Rooftop Solar PV Power Plant at East Calcutta Girls College, Kolkata Total Capacity: 25kWp

2 1. Salient Features 1. Location of the Solar PV Power plant I. Locality & Address East Calcutta Girls College P-237, Block-B, Laketown Link Road, Kolkata, West Bengal II. Latitude N III. Longitude E 2. Details of the climatic data i. Average Ambient temperature 25.7 C i. Average Wind speed 1.7m/s ii. Average Humidity 70.9% 3. Area for proposed SPV Plant (Sq. Mtrs.) 275Approx.) 4. SPV Power Plant i Output 25 kwp ii No. of modules to be installed Technical details of SPV Module i. PV Module type Polycrystalline Silicon Electrical Parameter Maximum Power ii. Rating 250Wp 6. Mounting Arrangement i Mounting Fixed Type on roof shed ii Surface azimuth angle of PV Module 180 o iii Tilt angle (slope) of PV Module (approx) 22 o 7. Inverter/ Power Conditioning Unit (PCU) I. Number of units 1 II. Rated Capacity 25kW III. Frequency 50 Hz IV. Efficiency >95% 8. Grid Connection Details Electrical parameters for interconnection 415 V, 3Ph, 50 Hz 9. Expected annual Energy Generation 34428kWh 1. Installation Time 30days

3 Introduction The world fossil energy source is rapidly depleting. The massive use of nuclear and fossil energy resources endangers the basic existence of human beings. Many people suffer from direct health damages. The predicted climate change, possible nuclear contamination and insoluble risks from plutonium production in nuclear reactors, pose even bigger dangers. Due to inequitable regional concentration of fossil and nuclear energy resources, a large share of the world population has no direct access to the benefits of contemporary energy supply. In India total domestic energy production of million tons of oil equivalent (MTOE) will be reached by and 844 MTOE by This will meet around 71% and 69% of expected energy consumption, with the balance to be met from imports, projected to be about MTOE by and MTOE by India s energy basket is blessed with a mix of all resources available including renewable. According to the Energy Statistics, 2013, 54% of the total installed electricity generation capacity is coal based. Over 70% of the electricity generated is from coal based power plants. Currently, renewable energy comprising of wind, geothermal, solar and hydroelectricity represent a 2% share of the Indian fuel mix. The Energy Statistics, 2013, states that import of coal has steadily increased from MTs during to MTs during There was an increase of 49.24% in gross import and 56.29% in net imports of coal in over the previous year. However, there was a decline of 53.91% in export of coal during the same period. The statistics puts a serious question mark over India s approach towards attaining energy security. It is very important to put considerable stress on clean and renewable sources of energy to achieve energy security, which is largely being hampered due to considerable import of coal and other fossil fuels. There are no physical and technological limitations to continuing the present distortions. Major benefits of grid connected solar power plants are furnished below: Power from the sun is clean, silent, limitless and free Photovoltaic process release no CO2, SO2 or NO2 gases which are normally associated with burning finite fossil fuel reserves and do not contribute to global warming Photovoltaics are now a proven technology which is inherently safe as opposed to other fossil fuel based electricity generating technologies Reduces or avoids the necessity to build new transmission/ distribution lines or upgrade existing ones Solar Powered Grid Connect Plants can act as tail-end energizers, which in turn reduces the transmission and distribution losses Provides a potential revenue source in a diverse energy portfolio Assists in meeting renewable portfolio standards

4 3. Solar Energy: A Way Forward The sun is the source of energy and life for us. Most of the energy we use has undergone various transformations before it is finally utilized, but is also possible to tap this source of solar energy as it arrives on the earth s surface. There are many applications for the direct use of solar thermal and photovoltaic energy. It is a technology which is well understood and widely used in many countries throughout the world. The most common use for solar photovoltaic technology is generating power for lighting, pumping water, generating grid quality power etc. As world oil prices vary, it is a technology which is rapidly gaining acceptance as it results in an energy saving measure in both domestic and commercial sector. Solar radiation arrives on the surface of the earth at a maximum power density of approximately 1 kilowatt per meter 2 (kw/m 2 ). The actual usable radiation component varies depending on geographical location. Cloud cover, hours of sunlight each day, etc. in reality, the solar flux density (same as power density) varies between 250 and 2500 kilowatt hours per meter square per year. As might be expected the total solar radiation is highest at the equator, especially in sunny, desert areas. Solar radiation arrives at the earth s outer atmosphere in the form of a direct beam. This light is then partially scattered by cloud, due or other atmospheric phenomenon. We therefore, receive solar radiation either as direct radiation or scattered or diffuse radiation, the ratio depending on the atmospheric conditions. Both direct and diffuse components of radiation are useful, the only distinction between the two being that diffuse radiation cannot be concentrated to use. Solar radiation arriving from the sun reaches the earth s surface as short wave radiation. All of the energy arriving from the sun is eventually re-radiated into deep space otherwise the temperature of the earth would be constantly increasing. This heat is radiated away from the earth as long-wave radiation. The art of extracting the power from the solar energy source is based around the principle of capturing the short wave radiation and preventing it from being re-radiated directly to the atmosphere. Solar photovoltaic power generation can be seen to have the following specific advantages: It is based on an inexhaustible and perennial resource (that has time scales of millions of years). The resource is more equitably distributed globally, thereby putting countries like India in an advantageous position vis-à-vis most of the developed countries. Local availability of the resource removes constraints like transportation of fuel (as in case of coal), transmission losses (as in case of electricity) etc. Increased use of solar radiation resource is likely to contribute positively to improvement of the environment (reducing pollution etc.) as also reduce the threat of climatologically disasters like global warming.

5 In terms of implementation, the power plants can be set up within a time scale of a couple of months, gestation periods that are much shorter compared to conventional options like coal based thermal power stations, hydroelectric power stations, nuclear power plants etc. Almost the entire power output is available during peak demand hours (and the matching could be made ideal with limited storage to extend operating hours in the evening), thus meeting a key requirement of the state electricity boards in India. Once installed, solar photovoltaic power plants provide an excellent hedge against price escalations, particularly in various fossil fuel resources. Concept diagram of the Solar module installed on the Roof & Connection diagram

6 4. Working principle of Solar PV System Solar Photovoltaic technology (SPV) enables direct conversion of Sun light into electricity. Photovoltaic cells, commonly known as Solar cells, are used to convert light into electricity. A number of Solar cells joined together make a Solar Photovoltaic module. The electrical output of a PV module is rated in terms of peak watt, which is the maximum power output that the PV module could deliver under standard test conditions of incident solar radiation of 1000 watts per square meter area, Air mass 1.5 and ambient temperature 25 C. A combination of few Solar Modules makes a Solar Array. Solar modules made of solar cells produce Direct Current electricity from light, which can be used to power equipment or to recharge a battery. An inverter is required to convert a direct current (DC) into an alternating current (AC). These systems can be grid connected or off grid power for remote. Most parts of India have about 285 sunny days. Average Solar radiation incident over the land is in the range of 4-7 KWh per square meter per day. Solar Photovoltaic power plant can be installed in land, on roof tops or even in water as a floating body. Floating solar power plant is a recent development initiated by NBIRT, Kolkata. The PV power plant can be grid connected or off grid power station for remote places. In grid connected plant, power generated from the plant is exported to the grid through inverter and export-import meter. Power generated from solar module is DC power which is converted to AC power using Inverter before feeding it to grid. Following diagram will explain the Grid connected SPV power generation system. Concept diagram of the Grid connected SPV system

7 5. What is a Solar Rooftop system? Solar Rooftop System is an arrangement of interconnected components installed on the roof of a building or work-shed with the purpose of converting sunlight into electricity. The installed Solar Panels absorb and covert solar energy directly into electricity. The DC electric current generated is converted into AC with the inverter. Solar Roof Top PV systems have been widely accepted worldwide. Major Indian cities, such as Kolkata, Chennai, Delhi, Mumbai, Bangalore, Hyderabad have introduced grid-connected roof-top systems. Roof top systems are also being installed in some of the educational and community institutions for reaping benefits of electricity saving. Roof-top Solar Systems Benefits: Reduce your electricity bills Earn benefits on electricity generation Contribute to the environment by reducing harmful emissions Natural cooling of the top floor 6. Background: East Calcutta Girl's Collage Lake Town is the fruitful outcome of a long struggle of some local residents who are committed to provide appropriate facilities for Higher Education among girls. After establishing and running the Govt. Sponsored Girls' High School in Lake Town successfully for several years, the Managing Committee of the school, in order to fulfil its long cherished goal and the local demand for setting up a Girl's Collage for the higher education of women, took up the matter with the

8 Education department of the Govt. of the West Bengal during the year Maenwhile a Society for Education, Health and Welfare was registered during the year with members comprising of eminent Educationists, Administrator, professionals, Retired Govt. Servants and industrialists. To expedite achievement of this noble objective, an Ad-hoc Committee was formed. Late Amiya Kumar Sen, the then Chief Secretary to the Goverment of West Bengal, became a member of the Ad-hoc Committee. With his initiative and active participation the committee pursued the matter in right earnest and convinced the Govt. about the necessity of the Girl's Collage in Lake Town. The University of Calcutta also granted affiliation to the "East Calcutta Girls' Collage, Lake Town". Accordingly with the approval of the Metropolitan Development Department and the Education Department of the Govt. of West Bengal, a collage building was construction on the Govt. land contiguous to the building of the Lake Town Govt. Sponsored Girls' High School. The Electricity bill of the College is become significantly high. In order to reduce the electricity bill the College has initiated some Renewable Energy Programme which comprise of installation of Roof top Solar Power Plant on College building. College has a large number of sunny roof shad area is available, where solar power plant may be installed. It is expected with the installation of the Solar Power Plant the Electricity bill of the College will reduce significantly.

9 7. College Location: Google Map location Google Earth Location 8. Site Visit Observations:- College Building has 4 Storied building The space is available at college Roof shed Top (Approx. 275sq.m) True South direction is about 15 toward with East The angle of inclination of the Shed is 14 with the horizontal DG Set 15kVA available to provide power during power cut CESC Power supply 440V, 3Phase, and 50c/s one 3phase meter.

10 9. Photographs of the proposed SPV Modules Installation area at college rooftop PHOTO 1 PHOTO 2

11 PHOTO 3 PHOTO 4 Total Sunny Space available on the Roof Shed 275Sq.Meter for 25kWp SPV Power Plant Angle of inclination with horizontal of the Roof Shed 14 Degree. Total distance from SPV Module to Net meter connection 20m(approx.)

12 10. NASA Meteorological data of the site:

13 11. Existing Power Supply Arrangements: Present approximate power demand of East Calcutta Girls College is being catered by local grid of CESC distribution system as a commercial consumer. There is a 3 phase CESC meter connections, which are supplying power to the different load areas. One 15 kva D.G. set provides power during failure of grid or during breakdown. The DG set is owned by College and run by them. 12. Existing Yearly Energy Consumption details: CESC Consumer No.: A/C Month & Year Billed Units (kwh) Gross Bill Amount (INR) Source: CESC Jul Jun May Apr Mar Feb Jan Dec Nov Oct Sep Aug Total Yearly energy consumption of the college 40016kWhr Yearly billing amount Rs. 2, 89, 009/- (Likely to be increased in future years) 13. Proposed Features of the Grid connected SPV power plant: It is proposed to install 25kWp Roof Top Solar Power Plants Likely energy generation on annual basic from 25kWp SPV Power Plant is 34428kWhr as per PVsyst simulation (PVsyst analysis is given in Annexure A).However, actual generation may be less assuming the local climatic condition. Average Savings of electricity per year Rs.2, 58,210/- (Assume cost of Electricity per unit is Rs. 7.5/-) Payback period is 7 years.(approx.)

14 14. Special Structure for installation of SPV Modules: During inspection of the roof shed NBIRT engineer has found that some parts of the roof shed are structurally weak. As the corrugated shed structure of the college is very old. It is suggested that to avoid direct load of the SPV module and mounting structure (Load Kg approx.) on the existing corrugated shed a Special type structure is proposed to be fixed with the existing structure and column. SPV modules and walk way will be installed on it. The Special Structure and the existing roof shed structure should be vetted by an experienced reputed structural Engineer before installation.

15 15. Description of the Main Plant Equipment: A solar photovoltaic module is constructed from individual solar cells. The power output of a single module shall be 250Wp. In order to enhance the power output a number of Solar modules are to be connected. Higher system voltage is created by connecting the solar PV modules in series. The modules connected in series are known as strings. The strings are connected to the String Junction Boxes (SJBs) and the SJBs are connected to the inverters. The inverter converts the Direct Current generated from the SPV system to Alternating Current. The AC power from the inverters are fed into LT panel and then to the transformer through isolators and circuit breakers. The grid connected SPV power plant will consist mainly of the following components, but will not be restricted to the same: Solar Photo Voltaic Modules Module Mounting Structures Inverters(Grid tied) Grid Connect Arrangements (Net Energy Meter) Cables and Connectors Lightning Protection and other protection devices Earthing Monitoring Systems It may be noted that the design parameters like ratings, type, quantities etc. described in this report are indicative. Necessary changes could occur as the detailed engineering of the plant progresses, as these depend very much on the availability of the same at the time of placement of order. However, the performance of the system will not have any major deviation.

16 15.i) Solar PV Modules Each of the PV modules to be supplied should have minimum declared output of 300Wp or more. The modules should be IEC and IEC certified. Modules to be supplied for the power plant should be made of crystalline silicon Solar cells. The SPV Modules should be tested & certified by an independent international testing laboratory. The module frames shall be made of corrosion resistant material, which shall be electrically compatible with the structural material used for mounting the modules. The module shall be provided with a junction box with provision of external screw terminal connection and with arrangement for provision of by-pass diode. The box should have hinged, weather proof lid with captive screws and cable gland entry points. 250Wp OF SOLAR PV MODULE SELECTED FOR THIS PROJECT Parameter Specification PV Module Capacity Certified by SPV Module type Mounting arrangement on SPV Module SPV module frame materials Cable Gland at module Junction box Max. Temperature rise of cells under severe working condition over max. working Temperature Voltage at Pmax Current at Pmax Open circuit Voltage (Voc)@STC Short circuit Current (Isc)@STC 250 Wp IEC Edition II & EIC I & II Mono/Multi-Crystalline On Module mounting structure Anodised Aluminium with corrosion resistant preferable. Yes 85 C V (approx.) 8.18 Amp (approx.) V 8.7 A Efficiency Above 15.5% Tolerance +/- 3 Front Cover High Transparent, low iron solar glass (tempered)- 4 mm (0.157 ) glass

17 Encapsulation Back cover EVA White Polyester Weather Resistance Junction Box IP 65 Cable Dimension Weight Junction box with mc plug connector cables, 1x4 Sq.mm, length 900 mm 1640mm X 982mm X 36mm(approx.) 17.45kg(approx.) Name of the some PV module manufacturers:- Vikram Solar, Sova Power,Sunshine Power,TATA power & Rene solar 15. ii)a) Module Mounting Structure The main challenge of designing the structure is to maintain the stability of the same while maintaining the aesthetic view. The mounting structure should be so designed to hold suitable number of modules in series. The frames and leg assemblies of the array structures are to be made of mild steel hot dip galvanized of suitable sections of angle, channel or any other section confirming to IS Stainless steel make nuts and bolts should be used. Most photovoltaic modules are designed to last for 25 years or longer. It is important that the other components in the system, including mechanical components, have lifetime equivalent to those for the PV modules. It is also important that the mechanical design requirements of the system be consistent with the performance requirements as well as with the operational requirements of the system. More specifically, the mechanical design should involve: Determining the mechanical forces acting on the system. Selecting, sizing and configuring structural members to support these forces with an adequate margin of safety. Selecting and configuring materials that will not degrade or deteriorate unacceptably over the life of the system. Locating, orienting and mounting the photovoltaic array so that it has adequate access to the sun s radiation, produces the required electrical output and operates over acceptable PV cell temperature ranges. Designing an array support structure that is aesthetically appropriate for the site and application and provides for ease of installation and maintenance.

18 The mechanical system to be provided should affect the array performance in several ways: Increasing the amount of incident solar radiation Avoiding shading Allowing the array to operate at lower cell temperatures Based on the above mentioned criteria the module mounting structure should be designed with a state of the art technology which describes the withstanding capacity of 200Km/hr wind speed and gathering maximum sun light with a tilt angle of 22 with the horizontal surface. A single structure will hold all the modules. The modules will be sited on the structure in landscape basis and one upon another. 15.ii) b) Fitting fixing arrangement on the shed The Modules shall be fitted on the roof shed with angle iron structure as shown. The Module will face true south as far as possible. At present only provision of modules on the roof shed shall be kept.

19 15.iii) Inverter The heart of the system is the inverter. The inverter converts the DC power to AC power to facilitate feeding into the grid. In addition it performs many other functions. The system exports power to the grid when the DC output from solar array is available. The 3 Ph output voltages and current are sinusoidal with low total harmonic distortion meeting IEC & IEC standards. Inverter should be having efficiency levels of 95% and above. The inverter capacity should be derived by the vendor after proper permissions from the competent authority. The output power factor of the inverter should be of suitable range to supply or sink reactive power. The inverter shall have internal protection arrangement against any sustained fault in feeder line and lightning in feeder circuit. The inverter should be three phase static solid state type power conditioning unit. Both AC & DC lines shall have suitable fuses and contactors to allow safe start up and shut down of the system. Fuses used in the DC circuit should be DC rated. The inverter shall have provision for input & output isolation. Inverter shall have arrangement for adjusting DC input current and should trip against sustainable fault downstream and shall not start until the fault is rectified. Inverter front panel shall be provided with display (LCD or equivalent) to monitor the following: DC power input DC input voltage DC current AC power output AC voltage (all the 3 phases and line) AC current (all the 3 phases and line) Power factor Provision should be available in the inverter for Remote Monitoring of all the parameters mentioned under paragraph above and other important data. As the application is grid connected, the three Phase inverter should be synchronized with Grid frequency of 50 Hz at 400 V AC voltages with more than 90% efficiency. Name of the some Inverter manufacturer:-abb, KACO, SMA

20 15. iv) Grid Connect Arrangements A special energy meter shall be installed in between the solar grid inverter and the building distribution board to measure gross solar AC energy production (the Solar Generation Meter ). A bidirectional (import kwh and export kwh) meter should be used for the purpose of net-metering. This net meter will be supplied by DISCOM. 15.v) Cables and Connectors Cables used in DC side should have the following characteristics: Insulation resistance: when 20 C >4.6100Ω.KM Nominal voltage: 1100V Without melting and flow at high temperature. Conforming IS1554 Conductors are insulated with XLPE. Resistant for heat, temperature, abrasion, UV, Ozone and hydrolysis With high mechanical strength water oil and chemical resistance. AC cable of 4 cores, 10 sqmm is to be used. Cables used in AC side must have the following characteristics. Temperature range -15 C to +70 C Voltage rating 1100 V Conductors are electrolytic grade copper which provides maximum conductivity. Conductors are insulated with XLPE. Flame retardant. Full fills IS vi) Lightning Protection The SPV Power plant should be provided with Lightning and over voltage protection. The main aim of over voltage protection is to reduce the over voltage to a tolerable level before it reaches the PV or other sub-system components. The source of over voltage can be lightning or other atmospheric disturbance. The Lightning Conductors should be made as per applicable Indian Standards in order to protect the entire Array Yard from Lightning stroke. Necessary concrete foundation for holding the lightning

21 conductor in position is to be made after giving due consideration to maximum wind speed and maintenance requirement at site in future. Each Lightning Conductor should be fitted with individual earth pit as per required Standards including accessories, and providing masonry enclosure with cast iron cover plate having locking arrangement, watering pipe using charcoal or coke and salt as per required provisions of IS. Shall ensure adequate lightning protection to provide an acceptable degree of protection as per IS for the array yard. If necessary more numbers of Lightning conductors may be provided. 15. vii) Earthing The earthing for array & LT power system shall be as required as per provisions of IS 3043:1987. Necessary provision should be made for bolted isolating joints of each earthing pit for periodic checking of earth resistance. Each Array structure of the SPV Yard must be grounded properly. The complete earthing system is to be mechanically and electrically connected to provide independent return to earth. All three phase equipment should have two distinct earth connections. An Earth Bus shall be provided to connect the individual equipment. For each earth pit, necessary Test Point shall have to be provided. All non-current carrying metal parts are to be earthed with two separate and distinct earth continuity conductors to an efficient earth electrode. 15.viii) Monitoring Systems Computer Aided Data Acquisition Unit shall have features for simultaneous monitoring and recording of various parameters of different sub-systems, power supply of the Power Plant at the DC side and AC side. The unit shall be a separate & individual system comprising of different transducers to read the different variable parameters, A/D converter, Multiplexer, De-multiplexer, and Interfacing Hardware & Software. Reliable sensors for Solar Radiation, Temperature and other Electrical Parameters are to be supplied with the data logger unit. The data acquisition system shall perform the following operations, which include the measurement and continuous recording of: Inverter Output Energy delivered to the GRID on local network in kwh Day / Week/ Month

22 Solar Radiation Pattern of the day / week/ month All data must be recorded chronologically date wise. The data logger shall have internal reliable battery backup to record all sorts of data simultaneously round the clock. All data are to be stored in a common work sheet chronologically. Representation of monitored data in graphics mode or in tabulation form will be displayed on the computer screen or can be printed out. All instantaneous data can be shown in the Computer Screen Provision should be available for Remote Monitoring through GPRS system. An internal connection shall be recognised to monitor the data from the remote location. Typical monthly data and power curve through remote monitoring system

23 16. Proposed Electrical Design of Solar PV power plant The design of 25 kwp solar PV array, each string will contain 20nos. of modules of capacity 250Wp. Such 5 parallel strings are connected to the 25kW inverter. The output of the inverter is connected to the LT panel. Output of the Inverters shall be connected to the Grid Interfacing panel. The LT panel is then connected to the local grid through net metering system. The complete Single Line Diagram is attached as Annexure-B. 17. System BOQ SR. NO. Description Qty. 1 25kWp PV Array 1Set 2 Module Mounting Structure 1Set 3 25kW Inverter 1Set 4 DC & AC Junction Box 1Set 5 DC & AC Cables 1Set 6 Earthing & Lightening Material 1Set 8 Cable laying, Termination & Fixing 1Set 9 SCDA Monitoring System 1Set 10 Integration and Installation 1Set 11 Connection with Grid with Net meter 1Set 12 Commissioning & Testing 1Set

24 ANNEXURES

25 PVSYST V /09/16 Page 1/6 Grid-Connected System: Simulation parameters Project : Rooftop Solar PV Power Plant at East Calcutta Girls' College Geographical Site Kolkata Country India Situation Latitude 22.5 N Longitude 88.3 E Time defined as Legal Time Time zone UT+5.5 Altitude 13 m Albedo 0.10 Meteo data: Kolkata MeteoNorm 7.1 station - Synthetic Simulation variant : Simulation parameters New simulation variant Simulation date Simulation for the 01/09/16 13h48 5th year of operation Collector Plane Orientation Tilt 14 Azimuth -15 Models used Transposition Perez Diffuse Perez, Meteonorm Horizon Average Height 15.0 Near Shadings No Shadings PVsyst TRIAL PV Array Characteristics PV module Si-poly Model YL250P-29b Original PVsyst database Manufacturer Yingli Solar Number of PV modules In series 20 modules In parallel 5 strings Total number of PV modules Nb. modules 100 Unit Nom. Power 250 Wp Array global power Nominal (STC) kwp At operating cond kwp (50 C) Array operating characteristics (50 C) U mpp 540 V I mpp 41 A Total area Module area 162 m² Cell area 146 m² Inverter Model Powador 30.0 TL3 XL Custom parameters definition Manufacturer Kaco new energy Characteristics Operating Voltage V Unit Nom. Power 25.0 kwac Inverter pack Nb. of inverters 3 * MPPT 33 % Total Power 25 kwac PV Array loss factors Array Soiling Losses Loss Fraction 3.0 % Jan. Feb. Mar. Apr. May 3.0% 3.0% 3.0% 3.0% 3.0% 3.0% 3.0% 3.0% 3.0% 3.0% June July Aug. Sep. Oct. Nov. 3.0% Dec. 3.0% Thermal Loss factor Uc (const) 29.0 W/m²K Uv (wind) 0.0 W/m²K / m/s Wiring Ohmic Loss Global array res. 219 mohm Loss Fraction 1.5 % at STC Serie Diode Loss Voltage Drop 0.7 V Loss Fraction 0.1 % at STC LID - Light Induced Degradation Loss Fraction 2.0 % Module Quality Loss Loss Fraction -0.8 % Module Mismatch Losses Loss Fraction 1.0 % at MPP Module average degradation Year no 5 Loss factor 0.4 %/year Mismatch due to degradation Imp dispersion RMS 0.4 %/year Voc dispersion RMS 0.4 %/year Incidence effect, ASHRAE parametrization IAM = 1 - bo (1/cos i - 1) bo Param System loss factors Wiring Ohmic Loss Wires: 3x10.0 mm² 100 m Loss Fraction 2.9 % at STC PVsyst Evaluation mode

26 PVSYST V6.47 Grid-Connected System: Simulation parameters (continued) 01/09/16 Page 2/6 Unavailability of the system 10.9 days, 5 periods Time fraction 3.0 % User's needs : Unlimited load (grid) PVsyst TRIAL PVsyst Evaluation mode

27 PVSYST V /09/16 Page 3/6 Grid-Connected System: Horizon definition Project : Simulation variant : Rooftop Solar PV Power Plant at East Calcutta Girls' College New simulation variant Simulation for the 5th year of operation Main system parameters System type Grid-Connected Horizon Average Height 15.0 PV Field Orientation tilt 14 azimuth -15 PV modules Model YL250P-29b Pnom 250 Wp PV Array Nb. of modules 100 Pnom total kwp Inverter Model Powador 30.0 TL3 XL Pnom kw ac User's needs Unlimited load (grid) Horizon Average Height 15.0 Diffuse Factor 0.93 Albedo Factor 30 % Albedo Fraction 0.21 Height [ ] Azimuth [ ] PVsyst TRIAL 11h 10h Horizon line Legal Time Plane: tilt 14, azimuth h 13h h 5 14h Sun height [[ ]] 45 8h h 30 7h 16h 15 Behind the plane 6h 1: 22 june 2: 22 may - 23 july 3: 20 apr - 23 aug 4: 20 mar - 23 sep 5: 21 feb - 23 oct 6: 19 jan - 22 nov 7: 22 december Azimuth [[ ]] 17h Behind the plane PVsyst Evaluation mode

28 PVSYST V /09/16 Page 4/6 Grid-Connected System: Main results Project : Simulation variant : Rooftop Solar PV Power Plant at East Calcutta Girls' College New simulation variant Simulation for the 5th year of operation Main system parameters System type Grid-Connected Horizon Average Height 15.0 PV Field Orientation tilt 14 azimuth -15 PV modules Model YL250P-29b Pnom 250 Wp PV Array Nb. of modules 100 Pnom total kwp Inverter Model Powador 30.0 TL3 XL Pnom kw ac User's needs Unlimited load (grid) Main simulation results System Production Produced Energy kwh/year Specific prod kwh/kwp/year Performance Ratio PR % Normalized Energy [kwh/kwp/day] Normalized productions (per installed kwp): Nominal power kwp Lc : Collection Loss (PV-array losses) 1.13 kwh/kwp/day Ls : System Loss (inverter,...) 0.26 kwh/kwp/day Yf : Produced useful energy (inverter output) 3.77 kwh/kwp/day PVsyst TRIAL Performance Ratio PR Performance Ratio PR PR : Performance Ratio (Yf / Yr) : Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 0.0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec New simulation variant Balances and main results GlobHor T Amb GlobInc GlobEff EArray E_Grid EffArrR EffSysR kwh/m² C kwh/m² kwh/m² kwh kwh % % January February March April May June July August September October November December Year Legends: GlobHor Horizontal global irradiation T Amb Ambient Temperature GlobInc Global incident in coll. plane GlobEff Effective Global, corr. for IAM and shadings EArray E_Grid EffArrR EffSysR Effective energy at the output of the array Energy injected into grid Effic. Eout array / rough area Effic. Eout system / rough area PVsyst Evaluation mode

29 PVSYST V /09/16 Page 5/6 Grid-Connected System: Loss diagram Project : Simulation variant : Rooftop Solar PV Power Plant at East Calcutta Girls' College New simulation variant Simulation for the 5th year of operation Main system parameters System type Grid-Connected Horizon Average Height 15.0 PV Field Orientation tilt 14 azimuth -15 PV modules Model YL250P-29b Pnom 250 Wp PV Array Nb. of modules 100 Pnom total kwp Inverter Model Powador 30.0 TL3 XL Pnom kw ac User's needs Unlimited load (grid) 1784 kwh/m² Loss diagram over the whole year Horizontal global irradiation +5.7% Global incident in coll. plane PVsyst TRIAL 1704 kwh/m² * 162 m² coll. efficiency at STC = 15.40% -4.5% Far Shadings / Horizon -2.4% IAM factor on global -3.0% Soiling loss factor Effective irradiance on collectors PV conversion kwh Array nominal energy (at STC effic.) -1.8% Module Degradation loss (for year #5) -0.4% PV loss due to irradiance level -8.4% PV loss due to temperature +0.7% Module quality loss kwh -2.0% LID - Light induced degradation -1.3% Module array mismatch loss (including 0.3% for degradation dispersion) -1.1% Ohmic wiring loss Array virtual energy at MPP kwh -2.2% Inverter Loss during operation (efficiency) 0.0% Inverter Loss over nominal inv. power 0.0% Inverter Loss due to power threshold 0.0% Inverter Loss over nominal inv. voltage 0.0% Inverter Loss due to voltage threshold Available Energy at Inverter Output -3.0% System unavailability -1.4% AC ohmic loss kwh Energy injected into grid PVsyst Evaluation mode

30 PVSYST V /09/16 Page 6/6 Grid-Connected System: P50 - P90 evaluation Project : Simulation variant : Rooftop Solar PV Power Plant at East Calcutta Girls' College New simulation variant Simulation for the 5th year of operation Main system parameters System type Grid-Connected Horizon Average Height 15.0 PV Field Orientation tilt 14 azimuth -15 PV modules Model YL250P-29b Pnom 250 Wp PV Array Nb. of modules 100 Pnom total kwp Inverter Model Powador 30.0 TL3 XL Pnom kw ac User's needs Unlimited load (grid) Evaluation of the Production probability forecast The probability distribution of the system production forecast for different years is mainly dependent on the meteo data used for the simulation, and depends on the following choices: Meteo data source MeteoNorm 7.1 station Meteo data Kind Monthly averages Synthetic Multi-year average Specified Deviation Climate change 1.0 % Year-to-year variability Variance 2.5 % PVsyst TRIAL The probability distribution variance is also depending on some system parameters uncertainties Specified Deviation PV module modelling/parameters 2.0 % Inverter efficiency uncertainty 0.5 % Soiling and mismatch uncertainties 2.0 % Degradation uncertainty 1.0 % Custom variability 2.0 % Global variability (meteo + system) Variance 4.4 % (quadratic sum) Annual production probability Variability 1535 kwh P kwh P kwh P kwh 0.50 Probability distribution Probability P50 = kwh E_Grid simul = kwh P90 = kwh P95 = kwh E_Grid system production kwh PVsyst Evaluation mode

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