performance optimization of solar pv plant through micro inverter

25
Performance optimization of Solar PV plant Through Micro Inverter Ashish Verma M.Tech (Energy System) 500022066 University of Petroleum and energy studies

Upload: ashish-verma

Post on 20-May-2015

980 views

Category:

Technology


1 download

TRANSCRIPT

Page 1: performance optimization of Solar pv plant through Micro inverter

Performance optimization of Solar PV

plant Through Micro Inverter

Ashish VermaM.Tech (Energy System)500022066

University of Petroleum and energy studies

Page 2: performance optimization of Solar pv plant through Micro inverter

Power scenario in India Growing scenario of Renewable energy

UPES

► Renewable energy accounts for approximately 12.04% of a total 214.86 GW of power generation capacity installed in India.

► Demand for power in India has been increasing due to the rising population, growing economy, and changing lifestyles.

► Despite substantial capacity additions, the power sector is still in shortage of energy.

► Peak demand shortage averages around 9%.

► Renewable energy installed capacity was grown at a healthy CAGR of 19% over FY07-FY12

Source: MNRE, CEA & Economic survey of India 2012

58%

9%

1%

2%

18%

12% CoalGasDieselNuclearHydroRES

FY07 FY08 FY09 FY10 FY11 FY12

10.2 12.3 14.4 16.820

24.5

Growth of Renewable energy installed capacity in India

CAGR 19%

Page 3: performance optimization of Solar pv plant through Micro inverter

India is largest EPC sector in renewable energy

in the World

Installed capacity of 27.29 GW(up to feb2013)

various mission and state policies for

enhancing the power generation capacity

through renewable energy(NSM,NBMMP ,Gujrat Solar

policy2009 etc.)

Target of Renewable energy mix of 15 %

upto2017

Total installed capacity of Solar PV was 10 MW

before 2009 and now its reached up to 1440MW (feb2013)

Expected CAGR of installed capacity of Solar

PV is 47 % during the 2011-16

Source :EFYtimes, MNRE,PV- Magazine, NAPCC

Break Up of Renewable Energy

Growth rate of Solar PV UPES

68.27%

13.01%

4.63%

8.43%

0.35%5.30%

Grid Interactive Installed capacity (In MW)

Wind

Small Hydro power

Biomass Power

Bagasse Cogenera-tionWaste to power

Solar PV

Page 4: performance optimization of Solar pv plant through Micro inverter

Different type of Solar PV plant and his component UPES

Grid Connected System & Component 1. Module

2. Inverter

3. Transformer

4. Distribution panel

Off grid System & Component 5. Module

6. PCU ( Charger controller /Inverter )

7. Battery

8. Distribution Panel

Decentralized System Suitable for where grid connectivity is poor or grid is not viable

Best option for Rural Electrification

Page 5: performance optimization of Solar pv plant through Micro inverter

Grid connected Solar PV plant cost is 8

Cr/MWp

Land according to technology used

(Crystalline & Thin film)

Highest cost sharing by PV module is

around 43%

Source: CERC

Break up Cost of Solar PV plant UPES

43%

7%2%12%

13%

13%

10%

% Sharing of Cost/MW

Module

PCU

Land Cost

Civil and General Work

Mounting Structure

Evacuation cost up to Inter connection point

IDC & Con-tingency cost

Page 6: performance optimization of Solar pv plant through Micro inverter

CUF which is ratio of actual energy produced from the plant to maximum possible output during the year

Radiation of the Site - Responsible of energy generation through solar PV Primary requirement for design of power plant Data me be instant(Irradiance) or integrated(irradiation )Comparable result found the inaccuracy of 20-25%

Losses in PV system Which cause the power actually delivered to the grid to be lower than the power produced from PV moduleCable loss Power Inverter Dust on the Module surface Ambient temperatureVarying insolation level

Performance parameter of Solar PV plant UPES

Page 7: performance optimization of Solar pv plant through Micro inverter

Reflection lossdata show that the module faced toward the equator with tilt angle of latitude ,yearly reflection losses is 1 % relative to STC

Soiling LossOccur due to dust and dirt particles Losses are generally 1%Reduce the power capability

Mismatch Effect Losses due to series and parallel connection of Module Module don’t have identical property

MPPT LossExtract the max power from Solar PV

Inverter Efficiency Stand alone ,Grid tied Efficiency measure how well it convert the dc voltage into AC voltage Efficiency of 95-98 % Less efficiency at low power

Page 8: performance optimization of Solar pv plant through Micro inverter

Temperature and climate conditionPower decrease according to temperature coefficient

Typical value for Crystalline module is -0.4- 0.45%/°C

Typical value for thin film module is -0.24-0.25%/°C

Design parameter of Plant Minimization of ohmic losses

Selection of efficient transformer and Inverter

Mounting position –proper air ventilation required

Inclination angle –max radiation can be obtained by optimum tilt angle which is

determine by the latitude of location

Module power degradation due to ageing-0.50% reduction of power Per year

90% of the max power up to 10 years and 80% of the max power next 15 years

Page 9: performance optimization of Solar pv plant through Micro inverter

Ensure continuous and reliable operation

Generating maximum energy

Maximize the economic performance

Ensure better PR

Life expectancy

Long term commercial utilization of plant

Need of optimization and evaluation of the Performance ? UPES

Page 10: performance optimization of Solar pv plant through Micro inverter

It build into or attached to each PV module

Each micro inverter convert Dc from each module to AC ,ready for grid connection

directly

Allow Each module to be an independent ,standalone , Solar AC grid connected

system with optimized energy production output

Less space for installation

No handling to high DC voltage

No Issue of single point failure

Life is more 20-30 % than String inverter

Market Growth is around $14.8Billion*

Source: Bloomberg Energy ,NREL, Enphase

Micro Inverter -Technology

Page 11: performance optimization of Solar pv plant through Micro inverter

Activation Process

Array Gun

Center feed – separate the individual branch circuit current for protection with

OCPD(over current protection device )

Communication domain

Engage cable – connecting the Micro Inverter

LCF – when more than one communication domain is installed ,for reducing the

noise level

Micro Inverter- Inverter automatic detect the utility scale voltage and export power

the utility services , connected with CB

Micro inverter Sub panel

PLC

Transformer –use to connect the commercial PV project to utility grid

Micro Inverter Component

Page 12: performance optimization of Solar pv plant through Micro inverter

Micro inverter operate similarly to central inverter System

Connected on each individually module

Handle much less power than central inverter

Yes ,Micro inverter are better option for optimization

Improve the energy harvest

Increase reliability

Simplify design ,installation

Better monitoring of Individuals

Dynamic MPPT efficiency is around 99.3%

Integrated with PLC

Micro Inverter

Is micro inverter best option to optimize the performance ? UPES

Page 13: performance optimization of Solar pv plant through Micro inverter

Connection of Micro inverter Integrated with Solar PV Module UPES

Source :Enphase Energy

Page 14: performance optimization of Solar pv plant through Micro inverter

Deliver design flexibility

Integrated intelligence 24/7 monitoring analysis Quick and simple design ,installation and management Increase energy harvestDue to minimization of system losses due to DC-AC conversion

Cost effective Cost is 10-12% high comparable to Central or String InverterEnergy production 18-20% high , so cost effectiveness is justified

Limitless scalability Include main panel board of PV load center that feeds multiple micro inverter sub panel distributed across the system

Benefits of Micro Inverter over other Inverter

Page 15: performance optimization of Solar pv plant through Micro inverter

Isolating Communication devices Reduce the communication noise

Better individual Monitoring

Reliable

System availability greater than 99.8%

No single point failure of system

Safe Low voltage DC

Reduce fire risk

Source: Enphase energy, NREL

Page 16: performance optimization of Solar pv plant through Micro inverter

PV module with String & Central Inverter

PV module with Micro Inverter

Micro Inverter V/S String ,Central Inverter UPES

Page 17: performance optimization of Solar pv plant through Micro inverter

Buyers wants to know what would be the PBP of investment

Saving and PBP is vary according to location

Dependent on various factor like cost of electricity from the grid

Feed in Tariff

Subsidy

Capital cost

Unpredictable factor , like radiation that affect the amount generation of electricity

LCOE (Levelelized cost of Electricity) – best option to comparing the

lifetime system cost with total power harvested over the period of time help to

determine the ROI

Economics behind installing Micro Inverter UPES

Page 18: performance optimization of Solar pv plant through Micro inverter

LCOE takes account of

1. Capital Cost- module cost , cost of power conversion electronics, Installation

2. Power harvesting –the total power harvested from the system ,through its life

time and monetary value of each harvested kWh ,determine the financial return

3. Operation & Maintenance – Directly proportional to the system reliability ,if it

is difficult to locate the source of problem ,the time spent on locating the fault will

increase the cost

Low LCOE show that RE power production is cheep and close to achieving GRID parity

Power optimizer are also used for extracting the max power from Module ,but cost is

increase $200 per module and need of central inverter same

Page 19: performance optimization of Solar pv plant through Micro inverter

Capital Cost :System Rating -7kWp

Module cost per Watt-$2 ($14,000)

String Inverter Cost per Watt - $0.5($3,500) Micro Inverter Cost per Watt- $0.75($5,250)

Total =$17,500 Total=$19,250

Cost is 10% more than String inverter

Installation CostNo high voltage DC switch and wire

No need to allocate area for inverter in building

According to market survey installation cost for String inverter is $16,500 and for Micro

inverter is $12,500 for 7kWp plant

Offer saving of 24% in installation cost

Enecsys Case Study : Architecture Cost Evaluation

Page 20: performance optimization of Solar pv plant through Micro inverter

PV Evaluation Lab (PVEL), in association with NREL ,recently performed a series of

field test to measure the shade impact on solar array output.

Solar Micro inverter shows the higher output than a string inverter in certain cases

Perform in Light ,Medium and Highly shade – 4%,8%,12% increased energy harvested

by Micro Inverter

Solar power electronics ,Inverter ,Micro Inverter ,Power converter have a range of

obtaining Max power curve

NREL developed different type of standard test procedure for simulating PV

performance under shade

Source: NREL , PVEL, Enphase energy

Shade impact On Power Generation Through Solar PV

Experimental Case study - String & Micro inverter

Page 21: performance optimization of Solar pv plant through Micro inverter

Characteristics Curve of System with Shade effect

Source: NREL , PVEL, Enphase energy

Page 22: performance optimization of Solar pv plant through Micro inverter

Adopted MethodologyPerformance tested on two identical 8kWp Array

One connected with String inverter and another is with Micro Inverter

Tested under different 78 shaded test condition

Semi Transparent mess in Module

Page 23: performance optimization of Solar pv plant through Micro inverter

Mesh with transparency of 36%

Shade configuration time is around 20 Minutes

Performance is measured with the RGM (Revenue grade meter )

Result

Micro Inverter perform better in shading

String inverter stuck in the a local MPP causing current limited operation of the

system

NREL’s result show that the approximately 50% of the energy lost due to shading by

string inverter ,specially in light shade condition

Micro inverter increase the harvested energy 4%,8% and 12% in light , medium and

high shade condition

Page 24: performance optimization of Solar pv plant through Micro inverter

Result Summary with Graph

Inverter output V/S Shade area

Page 25: performance optimization of Solar pv plant through Micro inverter

Question & Answers

Thank You….