The Polish Experience in PV Applications on the Example of 6 Years 1.1 kW System Operation at the Szczecin University of Technology ANNA MAJCHRZYCKA, ZBIGNIEW ZAPAŁOWICZ, AGNIESZKA KUCZYNSKA Department of Heat Engineering Szczecin University of Technology POLAND

Goal Observation Yearly electrical energy production by PV- system located on the roof of Department of Heat Engineering (DHE) of Szczecin University of Technology systematically decreased Evaluation of PV- system exploited in DHE building (Poland)

POLAND SZCZECIN Poland is situated in the Middle Europe on the Northern European Plain, with the northern border at the Baltic Sea and Carpathian Mountains in the south. Poland is located between 49º and 54º30’ N latitudes in a moderate climate zone influenced by both the Atlantic and Continental climate.

Poland

Poland geographic location Middle Europe Latitude: 49°00’ and 54°50’ N Longitude: 14°08’ and 24°09’ E Moderate climate zone

Western Pomeranian Province and Szczecin geographic location Latitude: 52°30’ and 54°30’ N Longitude: 14° and 17° E

Mean yearly irradiation in Poland Mean yearly temperature t=7.9 o C, Mean solar hours =1600 h

Sun irradiance Summer solstice Winter solstice II&III quater I&IVquater Hours Radiation intensity, kW/m 2

Polish regions with different conditions for solar energy utilization

Data of commissioned: February 1999 Location Direction S Angle of inclination44°

Grid connected PV system at Szczecin University of Technology G R I D INVERTER Photovoltaic panel Data monitoring and collecting Data monitoring and collecting

Description of PV installation 10 solar modules type M110 (Simens) Modules are connected in two parallel series Total power of PV system 1100 W p System PV co-operated with the Sunny- Boy inverter

Technical parameters of solar module type M110 (Siemens) Solar moduleValueUnit Maximum power [PMAX]110W Open circuit voltage [UOC] 43,5V Short-circuit current [ISC]3,45A MPP voltage [UMPP]35,0V MPP current [AMPP]3,15A Length/width [l/w]1307/652mm Weight [m]9,5kg Source:

The basic characteristic of the system : Industrial grade modules made by well known German corporation, Siemens. Covered with 3mm highly transparent glass to deliver more power and ensures high impact resistance and protection against hail, snow, ice and storms. Siemens M110- Monocrystal, with frame, no lead, 1316x 660x 35, 12V, 110W. The module contains two parallel strings of 72 connected 103x103 mm mono- crystalline silicon solar cells. Siemens M110 solar module has been designed for 12V grid connected applications. The junction box provides a high quality, dust protected and splash proof housing. The housing contains a rigid connection block with cage clamps and by-pass diodes providing “hot spot” protection for the solar cells.

Technical parameters of inverter type Sunny-Boy SWR 850 InverterValueUnit Nominal power [PNOM]850W Input voltage [UDC] V Output voltage [UAC] V Frequency [fAC]49,8-50,2Hz Max. efficiency [  MAX]  93 % Height/width/thickness [h/w/t]290/322/180mm Weight [m]18,5kg Source: Sale Price: $1,779.0

Inverter type: Sunny-Boy SWR 850

„Sunny Data” main window

Acquisition system

Measurement parameters Direct voltage and current generating by PV modules Voltage and power transmitted to grid Operating time Energy production in fixed time Other electrical parameters

Meteorological stations Stations of IMiGW in Western Pomeranian Province

Mean monthly sun irradiation – data from meteorological station IMiGW in Kołobrzeg

Meteorological station in DHE View of station

Parameters measure by the meteorological station Measurements: direct and diffuse solar radiation, pressure, temperature and relative humidity of air, power and direction of wind, surface PV module temperature.

Wind velocity sensor Measuring range - 0 –50 m/s Accuracy – discrimination threshold 0,5 m/s Impulse output 20 imp/s = 1 m/s

Wind direction sensor Resolution - 11,5° Accuracy - discrimination threshold 0,5 m/s

Sensors of solar radiation Pyranometrs CM11 produced by Kipp&Zonen According to the ISO 9060/WMO standards Secondary standard, high quality Spectral range (50% points) – 2800 nm Sensivity - 4 – 6 μV/W/m 2 Response time (95%) - 12 s

Atmospheric pressure sensor Measuring range –1100 hPa Accuracy - 1 hPa Resolution - 0,1 hPa

Sensors of solar radiation Zero offsets: thermal radiation (200 W/m 2 ) – ±7 W/m 2 temperature change (5 K/h) – ±2 W/m 2 Non stability (change/year) - ±0,5% Non linearity ( W/m 2 ) - ±0,6% Directional error (at 1000 W/m 2 ) - ±10 W/m 2 Temperature dependence of sensitivity - ±1% ( °C) Tilt response (at 1000 W/m 2 ) - ±0,2%

Sensors of solar radiation View of sensor and shadow ring

Relative air humidity sensor Measuring range - 30 –98% Accuracy – 2% in range 30-85% 3% in range 85-98% Resolution - 0,1%

Meteorological station in DHE View of station

Breakdowns of PV installation PV – system out of order Damage of inverter in following periods: from to from to Electrical energy was not produced. Breakdowns of acquisition system. Data was not collected in short time. Electrical energy was produced.

Yearly electrical energy production from 1.1 kW PV generator

Measurement parameters Direct voltage and current generating by PV modules Voltage and power transmitted to grid Operating time Energy production in fixed time other electrical parameters

Recorder Type RC12 Data storage 176 kB of memory Measurement period 2-60 min RS connection directly to computer

„Sunny Data” window

Monthly electrical energy production from 1.1 kW PV generator

Monthly electrical energy production by pV module in exploitation time

Reasons Variable weather conditions Breakdowns Ageing process of semiconductor elements

Daily electrical production on Daily electrical production on ,15 kWh 5,87 kWh 5,20 kWh 3,73 kWh 5,53 kWh 5,34 kWh 1,90 kWh 5,83 kWh

Daily electrical production on Daily electrical production on ,10 kWh 1,73 kWh 5,70 kWh 3,69 kWh 6,35 kWh 3,01 kWh 4,70 kWh 5,12 kWh 5,69 kWh

Daily electrical production on ,49 kWh 4,16 kWh 2,37 kWh

Daily electrical production on summer cloudless days ,35 kWh 6,00 kWh 6,02 kWh 6,08 kWh

Observation : Systematically decrease of yearly electrical energy production by PV- system located on the roof of Department of Heat Engineering (DHE) of Szczecin University of Technology

Relative electrical energy production: ,39 kWh100,0% 0,0% ,68 kWh91,4% 8,6% ,92 kWh89,1%10,9% ,40 kWh87,8%12,2% 2003not analysed

The average electrical energy production regarding to the months and 1m 2 of PV panel Februar 1999 – Februar 2003

Efficiency of PV modules

Average production of electrical energy and average solar irradiance

Monthly electricity consumption per capita

Municipal household’s electricity consumption per capita and energy production by 1.1 kW PV modules

Electrical energy production per 1m 2 of PV panel as the function of solar irradiation and average module’s efficiency

Annual electrical energy production from 1W p of installed power PV cell

It was observed that the amount of produced electrical energy systematically decreased. The rate of PV panels ageing was estimated by analysis of the parameters aquired during the operation of the system. It was found out, that based only of daily energy production, it is not possible to estimate this value in a reliable way. Approximate ageing rate of PV generator was estimated by verification of annual data concerning electrical energy production. Ageing rate of installation decreased asymptotically. Close to the end of operation of the installation, 15% decrease of electrical energy produced in photovoltaic cells was observed. Conclusions