Generalised Technical Specifications for Grid Tie …

1 Generalised Technical Specifications for grid Tie solar power plants The grid tie solar power plants without battery may be installed for any office buildings. As the office buildings have day time energy consumption, solar System without battery is suggested, as the battery is the weak link in the system and requires regular maintenance as well as replacement in every 2-3 years. Also the efficiency of the battery based system is less due to loss in the battery (around 15%). The shadow free area required for installation of solar plant is appx 150 (14 ) per KW. The solar panels may be installed on the roof of the building.

2 Sufficient area shall be available for servicing the system. The minimum clearance required from the parapet wall & in between row of panels is min 2 feet for cleaning the panels & servicing. In between the row of solar panels sufficient gap need to be provided to avoid falling of shadow of previous row on the next row. The Inverter / power Conditioning Unit (PCU) shall be placed indoor in a safe and easily accessible place. The bench mark cost fixed by Ministry of New and Renewable Energy (MNRE) for solar power plants without battery is as below: Upto 5 kWp > 5 kWp to 100 kWp MNRE provides 30% of the benchmark cost (or) 30% of actual cost whichever is less as capital subsidy for a maximum capacity of 100 KWp per system.

3 The details on how to decide the capacity of the solar system required for a particular building is enclosed as Annexure -I The detailed Technical Specifications , Standards & suggested Tender Eligibility Criteria are enclosed as Annexure IIA, IIB & IIC respectively. ANNEXURE I grid tie solar power Plant consists of following main components: 1. solar Photo Voltaic (SPV) Array 2. power Conditioning Unit (PCU) The SPV array & PCU may be sized as below: 1. solar Photo Voltaic (SPV) Array The Capacity of the solar power Plant (Wp) ie., Wattage of the SPV array, required for a particular building, may be calculated in following 3 steps.

4 The minimum of the 3 values may be taken as the capacity of plant. Step I: Capacity of solar Plant (Wp) = 50% of the connected load of the building For example: Sl. Connected Wattage of Number of Total Connected No Loads each load (W) Load Load (W) (4 * 5) 1 2 3 4 5 1. Tube Lights 4010 400 2. CFLs 185 90 3. Fans 705 350 4. Computers 1502 300 5. Printer 7001 700 6. Air Conditioner 22501 2250 ( ton split AC) Total Connected Load 4090 50% of the Connected Load = 4090/2 =2045 W (Value I) Hence recommended capacity of solar Plant in the building with total connected load of 4090 W is 2 KWp. Step II: Capacity of solar Plant (Wp) may be such that it generates 25% of the energy requirement of connected loads in the building in a day.

5 For example Sl. Connected Wattage of Number Total Connected Hours of Energy Required No Loads each load of Load Load (W) operation (Kwhr)* (W) (4 * 5) in a day (5*6) /1000 1 2 3 4 5 6 7 Lights 40 10 18 5 70 5 150 2 700 1 Conditioner 2250 1 ( ton split AC) Total Energy Consumption in a of 35 Units = Units 1 KWp solar Plant generates approximately 4 units a day. Hence 2 KWp (Value II) plant may be installed. Step III: Capacity of solar Plant (Wp) may be such that, the maximum energy generated by the plant in an hour is 50% of the energy consumption of the building in an hour. Energy consumption during 10 am to 3 pm (good sunshine period) may be taken for this calculation.

6 For example the energy consumption may be calculated as below: 1 2 3 4 5 Date Energy meter Energy meter Difference Average consumption Reading @ Hrs Reading @ (3-2) in an hour in Units Hrs (4/(15 Hrs- 10 Hrs)) 7456 7466 10 10/5 = 2 50% of the energy consumption in an hour = 2/2 = 1 unit Hence 1 KWp (Value III) solar plant which generates maximum 1 Unit in an hour may be installed. The minimum among the 3 values is 1 KW. Hence 1 KW SPV array may be selected. 2. power Conditioning Unit (PCU) The PCU / Inverter capacity, mentioned in KVA, shall be equal to SPV array capacity. Eg., 1 KWp PV array shall have PCU of 1 KVA capacity & 5 KWp PV array shall have PCU of 5 KVA capacity.

7 ANNEXURE-IIA Technical specification FOR grid TIE SPV power plants solar PV Array (KWp) To be filled based on the capacity of plant power Conditioning Unit (KVA) ---- do----- DEFINITION A grid Tie solar Photo Voltaic (SPV) power plant consists of SPV array, Module Mounting Structure, power Conditioning Unit (PCU) consisting Maximum power Point Tracker (MPPT), Inverter, Controls & Protections, interconnect cables and switches. PV Array is mounted on a suitable structure. grid tie SPV system is without battery and should be designed with necessary features to supplement the grid power during day time. Components and parts used in the SPV power plants including the PV modules, metallic structures, cables, junction box, switches, PCUs etc.

8 , should conform to the BIS or IEC or international Specifications , wherever such Specifications are available and applicable. I. Technical Specifications of Major Components of solar PV power Plant 1. solar PV modules and array 2. Module mounting structure 3. Junction Boxes 4. power Conditioning Unit 5. DC & AC Switches 6. Cables and installation accessories 7. Earthing and lightning protection 1. solar PV MODULES AND ARRAY (i) Only indigenous modules shall be used in the project. solar module shall be Crystalline (Mono/Poly) (or) Thin Film (or) Concentrator PV modules type. The peak power output of the PV Module shall be min 100Wp under STC.

9 Module Voc shall be minimum 21V. The total array capacity shall not be less than _____ KWp (to be filled based on the capacity of the plant) and this shall be operating at the DC voltage of ____V (to be selected based on capacity of the plant). The power output of the PV module must be reported under standard test conditions (STC). I_V curve of the sample module should be submitted. (ii) The mechanical structure shall withstand gusts of wind / cyclonic wind up to 150km/hr from back side of the panel. (iii) The offered modules must conform to the latest edition of any of the following IEC/ equivalent BIS Standards for PV module design qualification and type approval: Crystalline Silicon Terrestrial PV Modules : IEC 61215/IS14286 Thin Film Terrestrial PV Modules : IEC 61646/ Equivalent IS (Under Dev.)

10 Concentrator PV Modules & Assemblies : IEC 62108 (iv) In addition, the modules must conform to IEC 61730 1- requirements for construction & Part 2 requirements for testing, for safety qualification or Equivalent IS ( Under Dev.) (v) PV modules must also qualify Salt Mist Corrosion Testing as per IEC 61701/IS61701. (vi) SPV modules shall be certified by NABL/IECQ accredited test centre. The bidder shall submit appropriate certificates. (vii) Protective devices against surges at the PV module shall be provided. Low voltage drop bypass diodes shall be provided. (viii) Module Junction box (weather proof), where the module terminals shall be interconnected and output taken, shall be designed for long life out door operation in harsh environment as per the relevant BIS Specifications and protected against surges.