CIVITAS MODERN. Deliverable / Working Document No. Deliverable impact. Date

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1 CIVITAS MODERN Deliverable / Working Document No. Document title Deliverable Renewable energy production to feed buses with low environmental impact Date Dissemination level Responsible author(s) Contributing author(s) Public (PU) Claudio Garatti (ML) Mariangela Pacchieni CIVITAS MODERN Page 1 /12

2 Index 1 Summary 3 2 Main step of the project implementation - First step: analysis and evaluation of the existing system 4 - Second step: feasibility new system/ authorisation 6 - Third step: purchase process 7 - Fourth step: executive design of the photovoltaic system 8 - Fifth step: implementation of the photovoltaic system 12 Attachment: - Authorization to the municipality of Brescia - Analysis of the offers received - Technical report of the project CIVITAS MODERN Page 2 /12

3 1. SUMMARY Brescia Trasporti Policy has defined the environmental improvement as a fundamental strategic orientation with particular involvement in the choice of technologies available suitable for the mitigation of environmental impacts arising from transport. Brescia Trasporti has decided to implement the measure the according with the specific MODERN objective to reduce the dependency on traditional fuels using renewable power generation plant for electrical vehicles and improving the energetic efficiency of the existing transport system. The measure apply actions based on the application of new photovoltaic technologies to charge the battery of all hybrid busses. Substantially the main targets of the measure is to supply all the energy required to the hybrid busses of BST fleet with the energy produced by the new plant. Brescia Trasporti fleet has been equipped with four innovative busses, 8 meters long, EPT (Eco Power technology Ltd). They gives numerous advantages over electric propulsion pure thanks to a generator of electrical power connected to a micro-turbine powered by natural gas (Horus). This type of hybrid machine is characterized by extreme quietness and by the very low emission level. For this innovation Brescia Trasporti in 2003 has received the prize Innovation friendly environment. In 2009 Brescia Trasporti proposed to extend the existing (realized in 2008) photovoltaic system to reach a capacity of 100KWp in order to produce enough energy to feed the 4 busses within the fleet. The existing photovoltaic system of power to 50 KWp was built on a part of the roof covering bus depot, they have been installed in parallel to the surface of the roof 252 polycrystalline silicon modules. In February 2010, after the formal approval by the EC, Brescia Trasporti started with the first step, the research activity (task ) based on the improvement of the performances of existing system in order to define the executive design of a new plant. The preliminary project of a new plant was designed taking into the account: - The roof available space - The roof sun exposition - The shadow factors due to the chimneys and skylights - The space required for maintenance In august 2010 the Municipality of Brescia concessed a licence to extend the operating photovoltaic system; in this time Brescia Trasporti started the purchase process of the components (PVmodules and inverters). Because the tender showed that since 2008 the price of modules decreased significatively and the available budget was more than enough Brescia Trasporti decided to increase the peak power up to 76,8 KWp So it was decided to purchase the following configuration: - n. 4 inverter Refusol 17 K photovoltaic modules Heckert Solar PXL 200 In November 2010 the definitive project of the Photovoltaic system was completed; the plant will product around KWh/year, energy required for charging battery of four hybrid bus within the available fleet and two new buses upcoming in CIVITAS MODERN Page 3 /12

4 During january and february 2011 the new photovoltaic system was installed in according to the executive project; its testing and consequent entry into operation is expected within april 2011, time due to the entities involved (such as network manager or department of customs) for the plant/equipment trials. 2. MAIN STEP OF THE PROJECT IMPLEMENTATION FIRST STEP - ANALYSIS AND EVALUATION OF THE EXISTING SYSTEM The first stage began with the analysis and evaluation of the existing system. It has got a capacity of 50 kwp and it has been working since may It was realized on a part of the covering of the building, used as garage for the busses; in particular it is composed by 252 modules of multicristalline silicium, that are installed parallely to the covering surface: 216 of them are positioned on the south-east side of the roof over the shed number 1 and the other 36 modules are on the east side of the roof over the shed number 2; a covering of about 430 mq. The fotovoltaic generator consists of 21 strings, each of them has got 12 modules and it is connected to the only inverter that is present. The projectual solution chosen, didn t absolutely change the building, while it has made up a whole, without interfering with the activities that take place there. You can see the location of the installation in the following pictures: Figure 1 Lay-out existing system 50 KWp CIVITAS MODERN Page 4 /12

5 M Figure 2 Pitched roof n.1 before installation Figure 3 Pitched roof n.1 after installation The system has got an annual average production that is equivalent to approximately kwp, and that has got an energy-saving of 10 tep and a reduction of the emission in atmosphere equivalent to 24 tco2 every year. The production is about ten per cent of the total energy used by the electric loads connected that are present in that place. The first graphic shows the energy production cumulated after two years since the entry into operation of the system (may 2008-may 2010) The production is good if we consider the every-day sun radiations and the return of every components, there are anyway some possibilities to improve it: - Reducing the shadows of the chimneys and the balaustrades placed along the perimeter; - Using components that can get better results; - Connecting directly to the framework service in order to obtain a reduction of losses; the actual system is connected to the power center and from this to the framework services; - Using better cables and connectors to reduce losses. CIVITAS MODERN Page 5 /12

6 Graphic 1 Energy production (kwh); period: may april 2010 Electricity production (kwh) photovoltaic existing period from May 2008 to April mag-08 giu-08 lug-08 ago-08 set-08 ott-08 nov-08 dic-08 gen-09 feb-09 mar-09 apr-09 mag-09 giu-09 lug-09 ago-09 set-09 ott-09 nov-09 dic-09 gen-10 feb-10 mar-10 apr-10 SECOND STEP - FEASIBILITY NEW SYSTEM/ AUTHORISATION After having considered the availability of the existent spaces and the economic and financial possibilities for the expansion of the system, it has been presented a project to make bigger the existent system, in order to reach a capacity of 100 KWp. As you can see in the following figure, the project has got the same lay-out of the previous one, occupying the free surfaces on the south-east side of the roof. On July 7,2010 the preliminary project has been approved by resolution n 20 of Brescia Trasporti board of direction; in the same time the cda has also approved the purchase of other two hybrids busses (electric gas turbine), these will be part of the corporate fleet during 2011, improving the percentage of the hybrids of the fleet. On August 24,2010 we have received the authorization for the expansion by the Municipality, because it is the owner of the place where the company acts. CIVITAS MODERN Page 6 /12

7 Figure 4 - Preliminary layout of the new system THIRD STEP PURCHASE PROCESS After a market analysis of the existent technologies we have drawn up the technical specifications for the purchasing tender of the photovoltaic modules and the inverter. The offers received have been read through a technical economic analysis, that is contained in a document called technical economic evaluation for purchasing tender of photovoltaic modules and inverter. After the analysis of the offers, considering the decrease of the modules market prices compared to 2008 and the availability in terms of budget, Brescia Trasporti has opted for a raise of the total power of the new system, that will have a capacity of 76,16 KWp with the following lay-out: - N 4 inverters Refusol 17 k - N 384 photovoltaic modules Heckert Solar PXL 200 CIVITAS MODERN Page 7 /12

8 Policristalline Modules Heckert solar Maximum power : 200 Wp Maximum guaranteed tolerance: 0/+2% Efficiency of the module : 12,65% Maximum system voltage Pmax: 1000 V Current at maximal load: 8,02 A Voltage at maximal load: 24,95 V Open circuit voltage: 31,95V Short circuit current: 8,52 A Dimensions of the module (mm) : 990x1480x38 Weight of the module (kg) : 19 Cells (156x156) :54 Inverter Refusol 17 K Max PV-Power: 18,1 KW MPPT range: V Max DC voltage: 1000 V Max DC current: 37 A Max efficiency: 98% Efficiency : 97,8% FOURTH STEP EXECUTIVE DESIGN OF THE PHOTOVOLTAIC SYSTEM After having defined the components and their features, it has been defined the executive project for the realization of a photovoltaic system with a nominal capacity of 76,8 kwp ( AS SUM OF THE PLATE OR NOMINAL POWERS OF EACH MODULE IN CONTINUOUS CURRENT, MEASURED IN STANDARD CONDITIONS) intended to produce electricity in connection to the electricity distribution network at high voltage and with alternate current three-phase. The system, such as the existent one, will be installed on the covering with the exposition S-E as you can see in Figure 5 and as describe below. It will be electrically connected to the part of the property network downstream of the point of the energy delivery and the energy produced will be totally assimilated by a passive system of load CIVITAS MODERN Page 8 /12

9 M distribution. The new system will be directly connected to the electric power of the take charge of the hybrids buses Figure 5 - Lay-out photovoltaic system 76,8 KWp CIVITAS MODERN Page 9 /12

10 TECHNICAL REPORT OF PHOTOVOLTAIC SYSTEM Dati generali Generatore fotovoltaico Moduli fotovoltaici Strutture di sostegno Inverter (n 4) Connessione Rete Identificativo dell impianto: Soggetto responsabile: Ubicazione: Latitudine: Longitudine: Altitudine: Inclinazione e orientamento piano moduli: Percentuale annua d ombra sui moduli: Radiazione solare annua sul piano orizzontale: Radiazione solare annua sul piano inclinato: Temperatura ambiente media mensile: Zona vento: Velocità media del vento: Direzione prevalente vento: Potenza nominale (1) P n : Tensione alla massima potenza V m : Corrente alla massima potenza I m : Tensione massima (circuito aperto) V oc : Corrente massima (corto circuito) I sc : N moduli totale/in serie N stringhe complessive Tipo: Potenza nominale (2) P n : Tensione alla massima potenza V m : Corrente alla massima potenza I m : Tensione massima (circuito aperto) V oc : Corrente massima (corto circuito) I sc : Tipo di celle fotovoltaiche: Rendimento minimo garantito (3) : N celle Materiale: Posizionamento: Integrazione architettonica: Tipo: Tecnologia: Potenza nominale in c.c. P n : Corrente massima in c.c.: Tensione ammessa in c.c.: Potenza nominale in c.a. P n : Tensione nominale in c.a.: Corrente nominale in c.a.: Corrente massima erogata in c.a.: Rendimento di picco: Rendimento europeo: Rendimento minimo garantito (4) : Presenza trasformatore Distorsione, TDH lato c.a.: Fattore di potenza: Tipo Potenza Max in immissione BRESCIA TRASPORTI 2 Ing. Marco Medeghini BRESCIA via S. Donino, N E 158 m 8 [Tilt] ; - 70 S [Azimut] 0,5 % 1371,9 kwh/m ,3 kwh/m 2 1,7:25,1 C 1 2,0 m/s N-E 76,80 kwp 598,8 V 128,3 A 766,8 V 136,3 A 384/24 16 Heckert Solar HS-PXL Wp 24,95 V 8,02 A 31,95 V 8,52 A Silicio policristallino 13,65 % 54 Struttura in acciaio zincato e traversi in alluminio. In copertura Parz. Integrato Refusol 17 K PWM 18,1 kwp 37 A 850 V 16,5 kw 3x400 V 24,0 A 29,0 A 98 % 97,8 % 94 % No < 2,5 % 1 Trifase MT 60kW Prestazioni Energia elettrica producibile Circa kwh/anno CIVITAS MODERN Page 10 /12

11 energetiche (1) Somma della potenza dei moduli fotovoltaici a STC (AM 1,5, irraggiamento sul piano dei moduli pari a 1000 W/m 2, temperatura della cella fotovoltaici pari a 25 C. (2) Caratteristiche a STC (3) Il rapporto fra la potenza nominale o di piccoo di targa del modulo fotovoltaici tipo (espressa in kwp) e l area del modulo, compresa la cornice (espressa in m 2 ) (4) Il rapporto fra la potenza Pca in uscita e la potenza Pcc in ingresso dell apparato di conversione, con Pca > 30% della potenza nominale in uscita. The average annual production is estimated in kwh more or less, considering the sun ways characteristic of the geographical area of Brescia and the shading due to the series of modules and to the position of the roof. The system will be able to produce the energy necessary to the six hybrids of the fleet. In fact their average waste is between 25 kwh and 40 kwh, according to the batteries charge level: an average annual waste of kwh for each bus. Environmentally the energy production will give a saving of 0,531 kg CO 2 per kwh, equivalent to 44,3 TCO 2 /year and an energy saving of 19 TEP/year Data 1 Productivity analysis of photovoltaic system (76,8 KWp) MONTH Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec YEAR Energy radiate on horizontal level (kwh/mq) Energy radiate on module s level (kwh/mq) Energy loss for shadows (kwh/mq) 39,61 61,21 106,78 134,17 175,67 187,50 210,11 173,94 122,50 79,22 44,17 37, ,90 42,23 64,27 110,11 135,95 176,20 187,19 210,30 175,74 125,60 82,72 46,96 40, ,28 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 Loss power (%) 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% 0,0% Energy profit (kwh/mq) 42,23 64,27 110,11 135,95 176,20 187,19 210,30 175,74 125,60 82,72 46,96 40, ,28 Efficiency of the system 85,0% 83,8% 81,4% 79,4% 77,4% 75,4% 74,3% 74,6% 76,4% 79,2% 82,1% 84,1% 77,7% Production (kwh/kwp) 35,91 53,84 89,60 107,95 136,43 141,17 156,23 131,13 95,96 65,49 38,54 33, ,89 Loss for temperature Loss for temperature 1,97% 0,45% -2,42% -4,78% -7,14% -9,56% -10,91% -10,52% -8,38% -5,06% -1.58% 0,84% Loss for reflection -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% loss for dirty -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% Loss for irradiation level -2,86% -2,86% -2,86% -2,86% -2,86% -2,86% -2,86% -2,86% -2,86% -2,86% -2,86% -2,86% Loss for mismatching 0,00% 0,00% 0,00% 0,00% 0,00% 0,00% 0,00% 0,00% 0,00% 0,00% 0,00% 0,00% Loss in cable -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% -2,00% Conversion loss -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% -3,00% Other loss -5,00% -5,00% -5,00% -5,00% -5,00% -5,00% -5,00% -5,00% -5,00% -5,00% -5,00% -5,00% Average temperature ( C) 1,97% 0,45% -2,42% -4,78% -7,14% -9,56% -10,91% -10,52% -8,38% -5,06% -1,58% 0,84% Specific annual productivity (KWh/KWp) 1.085,89 Total annual productivity (KWh) Data 2 Total productivity kwh/year CO2 (kg/kwh) TEP existing plant ,58 new plant ,181 tot ,761 CIVITAS MODERN Page 11 /12

12 M FIFTH STEP IMPLEMENTATION OF THE PHOTOVOLTAIC SYSTEM During january and february 2011 the new photovoltaic system was installed in according to the executive project; its testing and consequent entry into operation is expected within april 2011, time due to the entities involved (such as network manager or department of customs) for the plant/equipment trials. Figures 6 - Installation of the photovoltaic system 76,8 KWp CIVITAS MODERN Page 12 /12