Photovoltaïc kit Study and projects concerning the production of photovoltaic solar energy

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1 The Photovoltaïc kit in a nutshell Strengths & Key activities : Ideal support for student projects around photovoltaïcs (ex: Sizing of an energy-autarchic site) provided with an example of didactic scenario Solar panels with adjustable inclination (Mobile by default with the possibility to fix them on the ground or a wall) Monitoring of the system data Software of sizing of a photovoltaïc system Study of the transformation (Polycristallin panels), storage (Battery and battery controller) and transportation of energy (Very Low Voltage switchgear and Inverter) Study of the energetic efficiency and of the inclination impact on the efficiency Activities of measuring, wiring and connecting, energetic balance, sizing and validation of selections of components, communication, technical, economical and environmental analysis Various possibilities of measuring for diagnosis (Voltages, Currents, Temperatures, Insolation ) Optional connection of a 400W/2V wind turbine to complete the activities related to renewable energies Possible evolution to a communicating structure (Ethernet, Gsm ) Main components 2 polycristalline photovoltaïc panels (80Wp) with insolation sensor electric cabinet including notably: PLC with data acquisition and digital display functions 2V/230W 200W inverter battery 2V 75Ah with temperature sensor and tight cabinet Data acquisition and processing software References : CH5: Photovoltaïc kit (Photovoltaïc components only: 2 panels (80Wp) and metal frame, Inverter, PLC and associated software, Battery and tight cabinet, Mercury relay, Shunts et cables) CH5-CH6: Photovoltaïc kit (All components - Cabinet to be wired by students) CH5-CH6-CH7: Photovoltaïc kit (All components Wired cabinet) CH8: Option Battery loader for the simulation of an auxiliary power source EO: Option Wind turbine (400W 2V)

2 System architecture Insolation sensor Local PC Photovoltaïc source (In CH5, CH6 and CH7) BATTERY BATTERY LOADER CONTROL and COMMUNICATION PLC Temperature sensor 230V INVERTER Option Loader (In CH8) Electric Grid VLV (dc) 230V 0A protection Distribution on terminal board 6A protection with 30mA differential circuit breaker Distribution on terminal board Electric protection and distribution (In CH6 and CH7) Functional description This product is sized to allow the study of the generation of electricity with photovoltaïc techniques and its storage It implements a complet chain of production, storage and distribution of energy With its modularity, it is the ideal support to run student projects around photovoltaïcs Examples of usage scenarii Power supply of a telecom antenna Power supply of a sail boat Solar panels subset It allows the conversion of solar energy in electricity. It is dedicated to an external usage and includes mainly : A frame mounted on 4 casters supporting 3 solar panels (2V - 80Wc - 2.6% of efficiency) An insolation sensor A connecting cable between the panels and the electric cabinet 2V 400W wind turbine subset (Option) It allows convertingthe wind energy in electricity It is dedicated to an external usage and includes mainly a 400W 2V wind turbine (Diameter:.5m) on a mast with the following characteristics: Internal load controller for all types of batteries Carbon-made blades Permanent magnet alternator Voltage electronic control

3 System architecture Wind turbine specifications Rotor Diameter: 46" (.4 meters) Weight: 3 lbs (6 kg) Start up wind speed: 7 mph (3 m/s) Voltage: 2 & 24 VDC (36/48 VDC available soon) Output: 400 watts at 28 mph (2.5 m/s) Electric cabinet subset It allows controlling the generation, distribution and convertion of power. It mainly includes : An electric cabinet with transparent door (000 x 750 x 320mm) An inverter 2V 230V, 200VA, 94% of efficiency A PLC (Load control,acquisition and communication of data) with shunts and mercury relay Circuit breakers and electric distribution relay Security management system Optional battery loader with two functions: Simulating the usage of an auxiliary source (ex: electric generating set) in addition to photovoltaïc panels Perform the battery load in case of a long period of non-exposure to sun rays (In order to maximise the battery lifetime) Power storage subset It allows the storage of the electricity generated by the photovoltaïc panels It mainly includes: A battery (2V, 75Ah) A battery cabinet with aerations A temperature sensor Main components PLC functions The PLC performs: The simple or double load control (Normal load or equalization load) and the compensation in temperature of the load control steps The limitation of unload by load shedding The acquisition of system data: Battery voltage Input current for battery Output current for battery Output DC current for panels DC current of the auxiliary electric generating set (ex: Battery loader) DC currents (Consumption outputs and 2) Battery temperature Insolation (W/m²) The processing of the system data (Averages, Sums ) The storage of production data (6 months of hour values, 4 years of day values) The communication of data to a computer (RS232 protocol) and their processing with the Datapex software (Provided with the PLC) or to an external modem (Please contact us for this configuration) The PLC includes a LCD display (2 lines of 6 digits) with the possibility to view measures and the state parameters of the system

4 Main components Functions of the Datapex software Datapex is the software associated to the PLC. It allows to get back the data stored in the PLC and to parameterize the PLC It is possible to control in real time the parameters and the behavior of the system It performs three main functions: Parameterization of the PLC (Possible also with the PLC pull-down menu) Adjustment of the control parameters (Voltage steps, time-lag) Viewing and control of the power flows of the system in real time Download and processing of the production data Knowledge of the different alarms Monthly and yearly automatic analysis of the minimum, average and maximum battery voltages Repartition of the power generation between the panels and the auxiliary source (ex: electric generating set) Consumption / Production balance compared to the consumption planned during the system sizing phasis All the data can be exported to Excel for complementary data processing. Examples of graphics downloaded from the PLC and the Datapex software Battery balance graphic Production / Consumption graphic

5 Main lines of the bill of materials Main components Polycristallin photovoltaïc panels BP 380U 65W 2V Qty CH5 2 CH5-CH6 CH5-CH6-CH7 Metal frame 3 positions 30, 45 and 60 degrees PLC: BP-GM 2V Cable: RS232 DB9/jack BPGM 2m Insolation sensor PT000 temperature sensor 5m Datapex software Battery: SB 2V 75Ah Battery cabinet 70L Sinus Inverter AJ W 2V Single phase Shunt Insulant shunt base Fuse varistor Mercury relay 35NC-2V Cabinet IP65 000x750x320 Bearing plate for cabinet No No 40A bipolar disconnecting switch Control switch 2V DC 2 2 No No Emergency circuit breaker Circuit breaker: Single phase 2A No No Circuit breaker: Single phase 0A Circuit breaker: Single phase 20A 2 No No Differential circuit breaker: 6A 30mA Power relay 30A 2Vcc No No Plastic compression gland, Nuts, Labels, Colliers, Bands, Terminal ends, Cables, Wires, Buttons, Raceway, Screws, Lamps, Ground bus No Mounting No No

6 Training approach Possible training activities Sizing & Energetic balances Functional analysis Sizing of a photovoltaïc system and evaluation of the energy generation Determination of the solar mask Estimation of electric consumptions Determination of the photovoltaïc field, the batteries, the inverter Usage of a software to size a photovoltaïc system Checking of the sizing data (Photovoltaïc power, Cable sections, Inverter power, Battery capacity, Types of protections Economical and environnmental anaylisis Economical and environnemental analysis (Case of an individual, of a company ) Return on investment depending on grants Comparison of a photovoltaïc investment with a connection to the network grid Production of power in developping countries Environnemental analysis Avoided CO2 emissions Question of a centralized electric production compared to a decentralized one (Network losses ) PLC & Communication Programmation parameterization of a PLC (ex: Download and parameterization of the production data) Study of the load shedding Study and set-up of the communication architecture depending on the chosen protocol Study of communication protocols (ISDN, Ethernet, GSM ) Intervention & Commissionning Wiring of the electric cabinet, connection of the panels, the batteries Commissionning of the system Set up of the data acquisition (Temperature, Insolation ) Set up of a power back-up (Real or simulated by the battery loader) Measuring Measuring and data analysis (Current, Voltage, Load, Temperature, Insolation) Determination of the optimal inclination Global efficiency of the system, Efficiency of the inverter Maintenance Diagnosis (Introduction of defaults: Disconnected cable...) Planning and organisation of maintenance works (Checking wire connections, Cleaning up the panels, Watching the batteries...) Replacement of a faulty component Training activities proposed by ERM Automatismes (Vocational training) Activity : Analysis and commissioning of the system Objective: Run the first commissionning in order to deliver the system to the customer Time line: Preparation of the commissionning work (Reading of the documentation, Functional analysis, Operating mode) On-site checking of the system conformity Parameterization and commissionning of the system Explanation of the working mode to the customer Writing of a report of first commissionning

7 Training approach Training activities proposed by ERM Automatismes (Vocational training) Activity 2: Preventive maintenance Objective: Replacing a defective component with the batteries delivering current to the electric receivers Time line: Identify the characteristics of the component, find a reference and prepare the purchase order Realize the work authorization demand Disconnect the solar panels and replace the defective component Re-establish the electric connections and control the behavior Establish the maintenance report and update the maintenance book Activity 3: Performing a modification of the system behavior and associated wiring Objective: The PLC has to control the load of the batteries with the back-up power source (ex: Battery loader option) Tile line: Modification of the control and power schematics in order to answer to the specification Selection of the new components to be used Checking of the circuit protections adapted to the new components Siting of the material in the cabinet and wiring Parameterization of the PLC, tests and commissionning of the new function Establish the maintenance report and update the maintenance book Training activities proposed by ERM Automatismes (Technological training) Activity : Compare and date (5h) Module.: Knowledge of the photovoltaïc kit Research of the elementary process used in the photovoltaïc kit Measure the insolation on one day to estimate the available energy Measure the powers and energies required by the electric receivers Module.2: Comparative study of electric sources Compare 2 autonomous systems of energy generation : Photovoltaïc kit and electric generating set Represent the functional organisation of the photovoltaïc kit Draw the electrical schematics of the Photovoltaïc kit (CAD) Activity 2: Analyse and validate the process (h) Module 2.: Analyse and validate the energy transformation Measure and modelize the characteristics of a solar panel Measure the energetic balance of an inverter Module 2.2: Analyse and validate the energy storage Identify the working point of the battery Study the characteristics of the battery: working point, capacity Check the circulation direction of the energy : reversibility of the battery Control the energy: control the load, load shedding Module 2.3: Analysis and validation of the energy distribution Protect the people and the materialsl Measure the power factor on the AC grid Module 2.4: Analyse and validate the transformation of information Modelize the characteristics of a current and voltage source Parameterize the PLC BPGM Activity 3: Design (2h) Module 3.: Sizing and choice of the components Size the main components of the system (Number of panels, System voltage, Battery capacity ) Select the relay of load control, its characteristics and technology: electro-mechanical or static Select an electr-pump: characteristics, low consumption

8 Information on the photovoltaic Transformation of luminous energy: photovoltaics and PN junction A photovoltaic cell is mainly made from silicon (Semiconductor: junction p-n). When a cell is exposed to electromagnetic solar radiations, light photons transmit their energy to the atoms of the junction. This energy allows the electrons to free the atoms, thus generating electrons (N charges) and holes (P charges). These charges are kept separated by and electrical field form a «potential barrier». Once the P and N charges are isolated, there is only to close the circuit between these 2 areas (P and N) to set the electrons in motion and thus create and electrical current. Contact front side Photons Transmitter Electrons Holes Collector Contact back side Current Efficiency of photovoltaic modules The efficiency of the modules depending on the different technologies shows a major differences. Technology Monocrystalline Polycrystalline Thin layer: Amorphous Typical efficiency Maximum efficiency obtained (laboratory) Calculating the efficiency: Radiation power on entering the atmosphere (Solar constant): 350W/m² Radiation power at ground level: 000W/m² Power obtained through photovoltaic conversion: 0 to 50W/m² Efficiency: to 5% Peak watt (Wc) Reference power unit which allows the comparison of cells and modules Maximum power released under standard testing conditions (Radiation on the ground: 000W/m² - Temperature: 25 C) Current-Voltage Characteristics The Current-Voltage characteristic of a crystalline module shows a maximum peak in power where tension nears 7/8Volts at 25 C and 000W/m2. The evolution depending on temperature shows that voltage decreases and the current increases when the temperature rises.

9 Information on photovoltaics (Continued) Average insolation in France Marseille Toulouse Nantes Lyon Paris Mulhouse Average insolation for a 30 South orientation The impacts of orientation and angle ( = South Orientation, Angle 30 ) Orientation South: Horizontal 0.93, Angle , Angle Angle 30 : Orientation East 0.9, Orientation South-east 0.96 Potential for the production of photovoltaic electricity on the French territory For information, the installation of a kwc demands 8m² of solar panels Production map by installed kwc: The three principal applications of the photovoltaic solar Autonomous system The module charges a battery which allows to use energy whenever is convenient. The charging and discharging of the battery is controlled and managed by an energy managing device. On some systems a data acquiring device allows to watch the working of the system Usually energy converting equipments are also included: Inverter : to provide the user with a conventional alternative voltage (230Vac) Charger : to provide a complementary charge from an auxiliary source (Emergency generating unit, Wind Turbine) This type of system necessitates a size that takes into account the location of the system, the need and the autonomy of the battery. Sun line The electrical energy produced by the solar modules is used directly by the receivers. There is no electrochemical storing. Usually the «sun line» generators are intended to power electrical motors with continuous or alternating current (for the latter an energy converting device is required). The main applications are those for which we can consider storing energy under a form other than electrical energy (for example : storing water, storing cold ) Other applications : applications for which the service rendered does not have special requirements linked to supplying energy: aeration, ventilation Connecting to the grid All or a part of the energy produced is injected in the electric distribution grid. There are two main variations : «Simple injection» : all of the energy produced is injected into the grid. «Emergency injection», with battery, allows to supply energy in an autonomous manner in case the public grid is not available (Power outage due to climatic or technical mishaps). Thus the distribution of electricity is guaranteed.