Wilfried van Sark, Utrecht University: No data, no performance - the importance of monitoring

IEA INTERNATIONAL ENERGY AGENCY

PHOTOVOLTAIC POWER SYSTEMS PROGRAMME

No data, no performance the importance of monitoring

Wilfried van Sark, Utrecht University Solar Event

7 October 2014, Den Bosch, NL



Content •! Motivation •! Work from IEA-PVPS-Task 13

–! Example: performance Italy –! Example: data from web scraping

•! Specific yield determination in the Netherlands

•! Task 13 reports



Motivation

•! PV is becoming a mainstream energy harvesting option 135 GWp power, end 2013

1 GWp in the Netherlands

•! Optimal performance is required

•! But, do we know

“How well is PV serving the world?”

Without DATA we cannot address PERFORMANCE

Task 13: Performance and Reliability of PV systems



International Energy Agency of the PV Power Systems Programme •! 29 members: 24 countries, EC, EPIA,

SEPA, SEIA, Copper Alliance •! Most recent member: Thailand •! Activities are carried out collaboratively on

a country basis along a number of technical and non-technical subjects

•! Currently, 6 Tasks are active

www.iea-pvps.org



Present IEA PVPS Tasks •! Task 1 - Exchange and dissemination of information on PV power systems

•! Task 2 - Operational performance, maintenance and sizing of PV power systems and subsystems (concluded 2008)

•! Task 3 - Use of PV power systems in stand-alone and island applications (concluded 2004)

•! Task 5 - Grid interconnection of building integrated and other dispersed PV systems (concluded 2001)

•! Task 6 - Design and operation of modular PV plants for large scale power generation (concluded 1997)

•! Task 7 - PV power systems in the built environment (concluded 2001)

•! Task 8 - Very large scale PV power generation systems

•! Task 9 - Deployment of PV technologies: co-operation with developing countries

•! Task 10 - Urban Scale PV Applications (concluded 2009)

•! Task 11 - PV hybrid systems within mini-grids (2013: combined with Task 9)

•! Task 12 - PV environmental, health & safety activities

•! Task 13 - PV performance, quality and reliability (2014 - 2017) •! Task 14 - High-penetration of PV systems in electricity grids (2014 - 2017)



Relevant PVPS Issues •! Scenario work •! Market development and trends •! Policy framework •! Business models •! New technologies and applications •! Urban and rural implementation •! Large scale deployment •! Environmental aspects •! Quality and reliability •! Grid integration



Task 13: Performance and Reliability of Photovoltaic Systems

ST 1: Economics of PV System Performance

and Reliability

ST 2: System Performance and Analysis

ST 3: Module Characterisation and Reliability

ST 4: Dissemination



Task 13: Analysis of PV System Performance

DATABASE



Task 13: Performance Ratio over Time

Installed Location Range of PR Avg. PR

1980s Worldwide 0.50 - 0.75 Individual estimates

1990s Worldwide 0.25 - 0.90 0.66

1990s Worldwide 0.50 - 0.85 0.65 - 0.70

1990s Germany 0.38 - 0.88 0.67 2000s France 0.52 - 0.96 0.76 2000s Belgium 0.52 - 0.93 0.78 2000s Taiwan <0.3 - >0.9 0.74 2000s Germany 0.70 - 0.90 0.84



Performance is going up Performance ratio IEA – PVPS Task 2 [Nordmann, 2007] PR from ~60% to >80% [Reich, 2012] 90% max?!



Motivation •! Performance has been increasing in the past decades

•! Still, reasons for lower performance than expected (or promised) are difficult to detect, due to insufficient monitoring (in particular 1-5 kWp residential systems)



Statistical analysis Italy •! Example size bin: 10-100 kWp, installed in 2007, full year

measurements for 2008-2012 (5 years) •! Courtesy: Francesca Tilli (GSE)



Italy All years averaged Larger systems somewhat better performing

# systems North: 58 Central: 48 South: 48



Data mining •! Market is introducing web

tools for system owners to share monitor data, e.g., SolarLog

•! Objective is to analyze PV performance data obtained by web scraping techniques that collect and organize these data automatically in databases

•! “What you see, is what you can extract”

•! Developed Python scripts (Panos Moraitis)



Results

Country Samples System Size kWp

Netherlands 728 11.1 Germany 764 15.6 Italy 532 13.1 France 325 15.1 Belgium 565 6.5

GER ITA NL FRA BEL

P

M

A



Results •! Yearly variation between 2011-2013 from 2-11%

NL GER BEL ITA FRA

2011

20

12

2013



Country 2011

2012 2013

Germany North 979±153 937±126 882±109

South 1081±154 1044±121 992±125

France North 1030±362 993±201 959±154

South 1099±96 1092±224 1103±166

Italy North 1219±170 1177±157 1094±148

South 1352±113 1337±199 1288±203

South: +6-18%

FRA GER ITA

Annual yield (kWh/kWp) ±(stdev)



Results: NL Geographical Variation

Region PR Annual Yield kWh/kWp

Irradiation kWh/kWp

Coast 79.3+/-2% 895+/-21 1165 Mainland 77.1+/-2% 833+/-19 1021

Temperature, wind ?



Task 13: Statistics on the Operation of PV Systems

AIM: Energy Yield-GIS or PR-GIS?



Determination of standard specific yield in the Netherlands •! Statistics Netherlands (CBS) annually publishes the

amount of installed capacity of photovoltaic systems: 722 MWp, end 2013 [1 GWp, mid september 2014]

•! PV generated electricity is calculated from the installed capacity using a full-load-hours model: the average capacity of the year is multiplied with 700 h, equivalent with specific annual yield: 700 kWh/kWp

•! Renewal of protocol is necessary: PV systems in the Netherlands now are producing much than 700 kWh/kWp according to market stakeholders

! DATA needed to prove that

•! Expert work group advice, open source data, installer data (representing ~2% of installed capacity)



Dutch performance data

Advice: 875 kWh/kWp (25% increase!), starting from 2011

! Presently, PV contributes 0.5% to electricity supply in the Netherlands (and increasing)

2012 877 kWh/kWp

2013 874 kWh/kWp



Conclusions •! Obviously, without DATA one

cannot say anything on PERFORMANCE

•! IEA PVPS Task 13, subtask 2 •! Collecting and analyzing data

–! From all participating countries –! Statistical analysis, web scraping

•! Want to contribute?



Thank you for listening!

Q&A

http://www.iea-pvps.org/index.php?id=57



Part 2: IEA PVPS Task 13 http://www.iea-pvps.org/index.php?id=57

1.! Review of Failures of Photovoltaic Module, Report IEA-PVPS T13-01:2014 2.! Analytical Monitoring of Grid-connected Photovoltaic Systems - Good Practices for

Monitoring and Performance Analysis, Report IEA-PVPS T13-03: 2014

3.! Characterisation of Performance of Thin-film Photovoltaic Technologies, Report IEA-PVPS T13-02:2014

4.! Degradation Behaviour of PV Modules under Different Accelerated Stress Conditions Based on Stress Conditions Evaluated from Real-time Outdoor Testing, Report IEA-PVPS T13-04: 2014

5.! Analysis of Long-Term Performance of PV Systems - Different Data Resolution for Different Purposes,, Report IEA-PVPS T13-05:2014



9th Task 13 Expert Meeting in Freiburg, Germany, April 2014

Global co-operation towards sustainable deployment of PV power systems



Documents

Wilfried van Sark, Utrecht University: No data, no performance - the importance of monitoring