Solar Plant Performance Assessment

Copyright © 2013 Mahindra EPC. All rights reserved.

Copyright © 2013 Mahindra EPC. All rights reserved.

Analysis Team Project Developer

EPC

Panel Cleaning

String Monitoring Inverter & LT Panel

Transformer & HT Switchgear

Control Room, SCADA, HT Panels, Auxiliary

Power

Weather Monitoring Station

General PV Plant Layout

Evacuation Structure

The solar asset management post commissioing is generally done by a dedicated Operations & Maintenance (O&M) team.

Prime Objectives of O&M team is to operate plant safely with minimum impact to environment & occupational health, while maximizing generation of the plant and minimizing downtime.

Solar Asset Management

Environmental Impact Analysis

Occupational Health & Safety Equipment Safety

Safety Trainings

Hazard Identification and Risk Analysis

Emergency Management Plan

Water Conservation

Minimize Downtime• Plant Monitoring

• Predictive Maintenance• Breakdown Maintenance

• Spares Management

Maximize Generation• Soiling Impact Analysis• Module Cleaning• Periodic Reporting • Benchmarking

Layout Processes for Plant, Personnel and Planet safety

Maximize Return on Investment

4

Maximizing Generation

Maximize Generation

Plant overview as seen through a PV Monitoring

solution

The current values should be within prescribed deviations. For e.g. 10% of max

•Cables to be checked for any fault / loose connection.•The string modules to be cleaned if dust layer is found

DC combiner

box output

Should be as per individual installed DC capacity

Module cleaning to be initiated if dust is found on the serving PV field

Equipment Standards & Limits Action plan in case of deviations

Transformer

parameters

Should not exceed standard design capacity

• Load to be monitored.• Shutdown to be taken for further checking

Plant Performance of individual cluster(s) may be affected due to underperforming string/combiner box

Impact

Due to deviation in parameters transformer will trip & lead to higher generation losses

Maximize Generation

Track Actual V/s Predicted values and take corrective action as per triggers

Summary of instantaneous power and cumulative energy generated at a single glance

Hourly performance ratio reporting for better generation tracking w.r.t peak hours

Power evacuation status

Monitoring of all relevant data in single window

Parameters Action Plan in case of deviation

Should be according to the prescribed performance ratio

Data from inverter and irradiation sensors to be checked.; In case of abnormality, individual equipments to be checked

Generation v/s actual Irradiation

Cluster wise PR values

Should be identical for all the clusters

Individual inverters and combiner boxes to checked for abnormalities if any

Standards & Limits

Impact

Performance of individual cluster(s) may be affected due to underperforming equipment

Maximize Generation

Summary of equipment parameters

Device Health

Real Time Monitoring of energy flow as per AC SLD

Parameters Action Plan in case of deviation

Energy Flow

Voltage & current should be balanced and normal.

Individual equipment to be checked for any abnormality.

Standards & Limits

Impact

•Abnormal values may lead to major breakdown of the respective equipment.•Warranties of the equipments will be at risk

Maximize GenerationReal Time Monitoring of graphs

Historical analysis of collected data. Plant performance evaluation. User-defined formulas to calculate efficiencies, trends, performance ratios,

estimation of losses and alarm notifications. Analysis tool to explore and detect errors and energy production losses. Fast and reliable access to large amounts of captured data. Remote monitoring and control enabled.

Performance Analysis

Case Study : Soiling LossCurent and Power Deviation for the Month plotted

Shows module o/p power losses by ≈ 7.5% in eleven days due to dust accumulation on PV module surface

Module power drop by 0.7% per day due to dust/soil accumulation on PV module surface

Performance Analysis

Case Study : Soiling LossCurent and Power Deviation for the Month plotted

Shows module o/p power losses by ≈ 7.5% in eleven days due to dust accumulation on PV module surface

Module power drop by 0.7% per day due to dust/soil accumulation on PV module surface

Performance Analysis

11

Minimizing Downtime

Activity Frequency

Impact Action Plan

•Oil filtration to be carried out.

•If after oil filtration the value of BDV is not improving then it should be completely changed.

•Yearly / Half yearly,

•Samples to be sent to authorised testing agency

•May lead to winding failure of transformer due to degradation of oil.

•This would lead to higher generation losses as transformer need to be sent to factory location for repairs.

CHARACTERISTIC TESTING OF

TRANSFORMER OIL

• BDV : > 60 KV• DENSITY : 0.89 gm / cc • APPEARANCE : Clear and Transparent• ACIDITY : 0.03 mg KOH/ gm (Max)• WATER CONTENT : 20 PPM (Max)

Minimizing Plant Downtime

BDV Test kit

FREQUENCY IMPACTS ACTION PLAN

•Proper connection tightness and cleanliness to be ensured.• preventive maintenance to be carried out in case of abnormalities.

Monthly

• Fire hazards due to overheating of cables due to loose connections if any.

PHYSICAL CHECKING OF COMBINER BOXES

PLOTTING OF I-V CURVES USING HIGH PRECISION ARRAY TESTER TO TRACE PERCENTAGE DEGRADATION

OVER A PERIOD OF TIME

Yearly

The activity helps in keeping the track of performance of modules and its degradation with time.

•If the set of modules found underperforming. Same can be informed to the manufacturers and new modules can be claimed under warranty

ACTIVITY

Minimizing Plant Downtime

ACTIVITY FREQUENCY IMPACTS ACTION PLAN

• Fresh air fan filters to washed for effective air flow.• Fan motors to be checked for free movement.

Fortnightly, Values should be greater

than 4 m/sec.

Under performance (Deration) of inverters subjected to higher temperatures

Monthly, the indicators

should be green in colour.

The inverters may be subjected to heavy voltage surges and would further develop into major fault.

•The surge arrestors should be immediately replaced if ”end of life” indication is ON

Airflow monitoring at inlets of inverter panel

Green Indication

Status of surge arrestors

Minimizing Plant Downtime

Annual PPM Tracker

EQUIPMENT FREQUENCY TO BE DONE BY

Switchyard equipments

HT Panel

Inverters

LT DB’s

UPS

Battery Charger

Motors

Earth Pits

Yearly

Yearly

Quarterly

Quarterly

Quarterly

Quarterly

Quarterly

Yearly

ACTIVITY

• Detailed servicing and checks to be carried out as per annual PPM tracker.

• Periodic testing of equipments to be carried out for proper functioning

Breakers Yearly

MEPC team in consultation with OEM

MEPC team

OEM/MEPC team in consultation with OEM

MEPC team

OEM/MEPC team in consultation with OEM

OEM/MEPC team in consultation with OEM

MEPC team

MEPC team

OEM

The preventive maintenance is carried out periodically and based on feedbacks on predictive maintenance depending on the priority

The equipments to be identified for action to be done onsite or by vendor.

Transformer Yearly

MEPC team in consultation with OEM

MEPC team in consultation with OEM

Combiner boxes Yearly

Annual PPM Tracker

Preventive Maintenance Schedule for minimizing plant downtime

Use of Specialized Testing Equipments for Maximization of Generation & Minimization of plant downtime.

Stocking of critical equipments for minimizing plant downtime

Array Tester Thermal Imager for checking any hot

spot/loose connectionsPower Analyzer for equipment efficiency

measurement

Transformer Oil BDV Test kit

Cable Fault Locator for fast identification & restoration of cable

faults

Cumulative Data

5 MW Rawra (Aug,12-Jul,13) 5 MW Rawra (Aug,13-Dec,13) 2 MW Lucknow (9 Aug,12-8 Aug,13)

2 MW Lucknow (9 Aug,13-Dec,13)-40.00%

-20.00%

0.00%

20.00%

40.00%

60.00%

80.00%

100.00%

73.1

0%

73.6

0%

79.7

0%

78.5

5%

79.6

0%

75.4

8%

82.4

0%

81.4

2%

-3.7

9%

-3.5

9%

-14.

05%

-16.

72%

11.9

6%

5.88

% -4.3

3%

-6.5

1%

6.37

%

0.58

%

-11.

32%

-13.

46%

Cumulative Data for Project Commissioned in 2012

Target PR Actual PR Change in Weather Change In Generation w.r.t. Guaranteed Change In Generation w.r.t. Target

5 MW Gajner (Feb,13-Dec,13) 15 MW Gajner (Feb,13-Dec,13) 10 MW Rawra (May,13-Dec,13) 20 MW Rawra (May,13-Dec,13)0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

80.00%

90.00%

82.0

0%

82.0

0%

78.3

4%

78.3

4%

84.1

5%

85.3

6%

84.5

8%

84.1

6%

6.33

%

6.18

%

11.3

3%

11.1

5%

14.8

7%

10.5

3%

26.3

4%

24.8

3%

9.13

%

44.7

1%

20.0

2%

18.5

9%

Cumulative Data for Project Commissioned in 2013

Target PR Actual PR Change in Weather Change In Generation w.r.t. Guaranteed Change In Generation w.r.t. Target

Cumulative data for Plant Up Time & CUF

*Plant Up Time for 5MW Rawra is low due to failure of one 1.25 MVA transformer.

2 MW Lucknow (9th Aug-12 to Dec-13)

5 MW Rawra (Aug-12 to Dec-13)

10 MW Rawra (Oct-13 to Dec-13)

20 MW Rawra (Oct-13 to Dec-13)

5 MW Gajner (April-13 to Dec-13)

15 MW Gajner (April-13 to Dec-13)

98.20%

98.40%

98.60%

98.80%

99.00%

99.20%

99.40%

99.60%

99.80%

100.00%

99.38%

98.78%

99.87%99.68%

99.86% 99.90%

Plant Up Time

15.00%

16.00%

17.00%

18.00%

19.00%

20.00%

21.00%

22.00%

23.00%

24.00%

25.00%

15.72%

20.78%

19.01% 18.73%

20.61% 21.05%

15.84%

20.93%21.63% 21.37%

21.04% 21.30%

CUF CUF with 100% grid availability

20

Intricacies in a typical 20 MW Solar PV Plant

20Copyright © 2013 Mahindra EPC. All rights reserved.

3

250,000 photovoltaic modules

2

Total Surface Area:

140 Acres

4

30 Inverters

Remote area

550 Transformers

6

350 KMs of Cable

7

8

240 Combiner Boxes

6 Km of Plant Perimeter

Remote Monitoring & Control is CRITICAL for solar plants

7,800,000 Data Points stored every day

1

9

Traditional Monitoring &

Control Solutions

Evolution of Monitoring & Control Solutions

21Copyright © 2013 Mahindra EPC. All rights reserved.

Manual Monitoring1 Basic Equipment

Monitoring

2Basic SCADA system

3M

ahin

dra

Sola

r PV

SCA

DA S

oluti

on

Complete Equipment Monitoring (Module to DB) – CB, Inverters, Transformers

Equipment Control Options Integrated Solution – Security & Surveillance, Access Control, Module cleaning, spares management, license management, billing & reporting

Vendor Agnostic – Any equipment, any make

Comprehensive data monitoring -- 150 parameters on inverters

Customizable to user preferences – Trends, Reporting

Scalable – for same plant and across multiple plants

Intuitive User Interfaces

Dynamic Dashboards

Cloud based – Real time data access anytime, any where

Events & Alarms Management – SMS notifications Predictive Analytics –

Real time Generation forecast; early fault detection

Mahindra Solar SCADA Solution

Domestic & International Clientele

Over 8,000,000 data points monitored daily. Consistently being analyzed using advanced analytics to deliver

•Business reporting•KPI evaluation •Plant indexation and

benchmarking •Preventive maintenance•Resource Monitoring •ERP •Operations and

Maintenance

85 MW

MONITORED