• Indigenously manufactured PV modules should be used.
• The PV module should have crystalline silicon solar cells and must have a certificate of testing conforming to IEC 61215 Edition II / BIS 14286 from an NABL or IECQ accredited Laboratory.
• The power output of the module(s) under STC should be a minimum of 100 Wp at a load voltage* of 16.4 ± 0.2 V. Vnom 12V.
• The open circuit voltage* of the PV modules under STC should be at least 21.0 Volts.
• The module efficiency should not be less than 14 %.
• The terminal box on the module should have provision for opening to replace the cable, if required.
• PV modules must be warranted for their output peak watt capacity which should not be less than 90 % at the end of 10 years and 80% at the end of 25 years.
• Identification and Traceability

Each PV module used in any solar power project must use a RF identification tag. The following information must be mentioned in the RFID used on each module (This should be inside the laminate and must be able to withstand harsh environmental conditions.)

• Name of the Manufacturer of PV module
• Name of the manufacturer of Solar Cells.
• Month and year of the manufacture (separately for solar cells and module).
• Country of origin (separately for solar cells and module).
• I-V curve for the module.
• Peak wattage, Im ,Vm and FF for  the module.
• Unique serial no and model no of the module.
• Date and year of obtaining IEC PV module qualification certificate.
• Name of test lab issuing IEC certificate
• Other relevant information on traceability of solar cells and module as per ISO  9000 series.

 

2. Battery

 

• Tubular Lead Acid battery having minimum rating of 2 V 200Ah &12V, 150 Ah & higher capacities at C/10 discharge rate.
• 75% of the rated capacity of the battery should be between fully charged and load cut off conditions.
• Battery should conform to the latest BIS/ International standards.

 

3. Balance of system (BOS)

• Cables should confirm to applicable standards i,e IEC 60189, IS 694/ IS1554, IS/IEC 69947.
• Switches / Circuit Breakers / Connector should confirm to IS/IEC 60947 part I,II,III, EN 50521 standards.
• Junction Boxes should confirm to IP 65 for outdoor / IP 21 for indoor use and IEC 62208 standards.
• SPV system design should  confirm to IEC 62124 standards
• Installation of systems  should confirm to IEC 60364-7-712  standards

 

4. Power Conditioning Unit (PCU)

The PCU should convert DC power produced by SPV modules, in to AC power and adjust the voltage & frequency levels  to suit the local grid conditions. The inverter shall interconnect and feed power to the LT power supply of the building and also shall have the provision to power critical loads.

Common Technical Specification :

Control Type : Voltage source, microprocessor assisted ,  output regulation

Out put voltage : Single Phase, 230 V ac ( +12.5 %, - 20 % V ac)

                       : 3 phase, 415 V ac ( +12.5 %, - 20 % V ac)

Frequency:  50 Hz ( +3 Hz, -3 Hz)

Total Harmonic Distortion : less than 3%

Operating temperature Range : 0 to 55 deg C

Inverter standards :

Inverter should comply with IEC 61683/IS 61683 for efficiency and Measurements and should comply IEC 60068-2 (1, 2, 14, 30) / Equivalent BIS Standard for environmental testing. Inverter should supervise the grid condition continuously and in the event of grid failure (or) under voltage (or) over voltage, Solar System should be disconnected by the circuit Breaker / Auto switch provided in the inverter.                

Power Control : MPPT

Other important Features/Protections required in the INVERTER

• Automatic morning wake-up and nightly shutdown
• Mains (Grid) over-under voltage and frequency protection
• Fool proof protection against ISLANDING.
• Included authentic tracking of the solar array’s maximum power operation voltage (MPPT).
• Array ground fault detection.
• LCD and piezoelectric keypad operator interface Menu driven
• Automatic fault conditions reset for all parameters like voltage, frequency and/or black out.
• Surge arresters on AC and DC terminals for over voltage protection from lightning-induced surges.
• INVERTER should be rated to operate at 0 –55 deg. Centigrade unless provision for air conditioning is included in INVERTER
• All parameters should be accessible through an industry standard communication link.

• Overload capacity (for 10 sec) should be 150 % of continuous rating

 

Harmonics Standard :

As per the standard of IEEE 519, the permissible individual harmonics level shall be less than 3% (for both voltage and current harmonics) and Total Harmonics Distortion (THD) for both voltage and current harmonics of the system shall be less than 5%.

Technical and interconnection requirements