REtopia 2015Troubleshooting Renewable Energy Industry Problems

(TREP)

Problem Statement 1:

• Company name: GSES India Sustainable Energy Pvt. Ltd.• Current installed capacity of large grid connected solar

power plants in India is more than 4GW. The sudden scaling up of grid connected PV market in India has created an unhealthy competition among the various stakeholders leading to compromised quality standards. PV system failures occur primarily due to erroneous procedures and inexperience in design, installation and O&M of a plant; which could easily be controlled by adhering to best practices and applicable standards.• What could be the best practices for the above stated issue?

Design

Site Survey

Civil Structure

Mechanical Structure

Module Selection

Cable Selection

Electrical Equipmet

Implementation

Civil

Mechanical

Electrical

Project Management

Site Supervision

O&M

Module Level Monitoring

Inverter Level Monitoring

Soiling Losses

Seasonal Tilt

Design• Site Survey• Shade Analysis• Solar Resource Measurements

• Irradiance• Sunny Days• Temperature

• Site Topography and Contour Study• For designing the foundations

• Soil Testing• As per procedures under IS 2720

• pH analysis of soil• Alkaline soils causes more corrosion

• Civil Structure• Concrete mix ratio (for foundation works)

• Follow IS 456-2000• Foundation Design

• Mark the true North• WRT marked North, mark the foundations and structures.

• Cable Trenches• Separate for AC and DC cables

• Earthing Pits• Separate System and Structure earthing provisions.

• Mechanical Structure• Array Design

• Wind Load• Dead Load• Seismic Load• Packing Density• Tilting/Tracking Systems( Single Axis, Double Axis)

• Cable Trays• Separate for AC and DC cables

• Material Selection• Weather History• Soil pH

• Module Selection• Type

• Temperature coefficients• Performance under diffused light• Efficiency• Cost• Module Vmp

• Manufacturer• Previous track record• STC record of modules• Frame Design

• Water Resistant, dust layer, drain provisions• PID Characteristics

• Certified PID Free • IEC 61215• IEC61270-1&2

• Electrical Equipment• DC Protection

• Fuses, Surge Protection Device, terminal blocks( IS 12729- 2004)• AC Protection

• Circuit Breakers• Inverters

• Grid Tie Inverter• Metering System

• Bi Directional Meter(IS 12346 -1999, IEC 60736)

• Cable Selection• AC

• Use of copper cables for short distance laying.• Use of steel reinforced high strength aluminum stranded cables for long

distance laying.• Using standard cable selection process.( IS 694-2010)• UV protected, TUV Certified. IEC 60364- 712.

• DC

• Proper Crimping. Heat Shrinkable sleeves must be used at Junction Box end up to lugs.

• Good Quality MC4 connectors• TUV Certified. IEC 60364- 712.

Implementation• Civil• Constantly verify each stub/foot for accurate alignment• Constantly check and measure the distance (Horizontal and

vertical) between stubs is as per drawing or not• Ensure proper water curing with specific frequency

• Mechanical• Ensure the structure is properly galvanized

• Use Alcometer • Refer BS 4652

• Fasteners • As per design• Ensure proper torque( use torque Wrench)

• PV Module tilt angle and alignment• Ensure Using Inclinometer

• Diagonal alignment of PV array structure

• Electrical• Cables

• Ensure that the designed cables and instruments are used• Free flow of cables should not be restricted

• Equipment• Ensure the designed equipment are used

• Earthing• Ensure separate system and structure earthing( IS 3043- 1987)

• Connectors• Ensure usage of correctly rated connectors( IS 8804-1993)• Proper crimping process

• Site Supervision• Certified and Competent supervision team.

• Project Management• Maintaining the schedules.• Knowledge Management

Operations and Maintenance• In the light of growth in the PV Market, the industry

must focus on operating and maintaining systems• PV installation lifetimes are expected to be 25 years or

more.• Installation of Weather monitoring system .• Finding out the performance ratio.• Feasibility of Module level online monitoring.• Module Cleaning

Operation and Maintenance• WMS• Pyranometer

• Insolation measurement• Humidity • Ambient Temperature Sensing• Module Temperature Sensing• Wind Speed measurement

• Module Level online monitoring system• Used for PID analysis• Module Performance analysis• Soiling Losses Analysis• Performance Ratio Analysis

• Inverter Level online monitoring system• Used for PR analysis

• Soiling Losses• Availability of water• Cleaning schedules depending upon cities.

• Seasonal Tilt• Manual seasonal tilting for optimal performance.

• WMS for plants more than 1 MW.• Module level monitoring data analysis for

troubleshooting.• Third party auditor/ auditing mechanism.