1. Technical and Economic Characteristics
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS
PHOTOVOLTAIC SYSTEMS
Technical and Economic Characteristics
Prof.dr.sc. Damir Šljivac
Josip Juraj Strossmayer University of Osijek, Croatia
Faculty of Electrical Engineering
Department of Power Engineering
phone:
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

2. Average value is called solar constant: E0sr=1367.7 W/m2
Sun Energy
Sun radiation energy E0 coming to the other edge of Earth athmosphere depending on the Sun-Earth distance:
E0 = W/m on optimal angle surface (vertical to Sun radiation direction)
Average value is called solar constant: E0sr= W/m2
For different Sun-Earth distances:
where: r – average Sun-Earth distance
R - real Sun-Earth distance (regarded constant in a day)
Photovoltaic Systems as Actuators
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3. Sun radiation is calculated approximately as: [W/sqm]
where: ε ellipse eccentricty, n day in a year
Total daily energy in [J/sqm] by irradiation of horizontal surface:
ωs hour angle of the Sun (12h=00, 13h=150, 15h=450);
Φ geographical width of the regarded microlocation;
δ Sun declination (angle between lines passing center of the Earth, Equator and Center of the Sun)
Photovoltaic Systems as Actuators
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4. δ Sun declination ωs hour angle
Photovoltaic Systems as Actuators
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5. Passing the athmosphere:
Losses in direct Sun radiation energy
depending on atmospheric conditions:
- clear/cloud sky, pollution (dust), ozone, vapor layers, above sea level…
Maximal Sun radiation on Earth surface vertical to radiation: 920 W/sqm daily
Due to Earth rotation: in average up to 230 W/sqm daily, which is resulting in average of
5.52 kWh/m2 of energy, depending on the insolation duration (geo. width, season, atmosphere…)
Photovoltaic Systems as Actuators
of Regional Development
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6. Annual Energy from Sun Radiation vs. Energy Reserves and Needs
Total Earth surface: 510.1x106 sqkm resulting in average annual Sun radiation energy over 109 (billion!!!) TWh/yr (Enormous!!!)
Annual Energy from Sun Radiation to Earth
Direct Usage of Sun Energy
(3) Overall Natural Gas Reserves
(4) Overall Coal Reserves
(5) Overall Oil Reserves
(6) Overall Uranium Reserves
(7) Annual World Energy Consumption
Photovoltaic Systems as Actuators
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7. Big problems in Sun radiation usage (in electricity production)
1. Small density of energy flow, Oscillation in radiation intensity during the day, season,… Dependance on climate conditions, Radiation intesity (noon) is not coincident to electicity consumption intensity (evening), Impossible or very expensive storage, High specific investment costs (PV particularly) compared to conventional (fossil, nucler, big hydro) or even non-conventional (wind, biomass, geothermal) energy technologies
Result: photovoltaic (PV) electricity production is very expensive, unefficient and still very small compared (even) to other RES in electricity, but high incetives are resulting in the fastes incerase!
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

8. Share of RES in final (total) energy consumption in 2011
Source:
REN21 Renewable 2012 Global Status Report
Photovoltaic Systems as Actuators
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Share of RES in Electricity Production in 2011

9. Trends in technology and usage of RES 2009 - 2011
1 USD (2011) = EUR
Source: REN21 Renewable 2012 Global Status Report
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

10. Average increase in RES capacities and biofuels production
Sun radiation based technologies for heat and electricity with highest increse! PV particularly!!!
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS
Source: REN21 Renewable 2012
Global Status Report

11. How to determine Sun radiation on a location?
Option 1: Measure with Pyranometer (thermic or semiconductor) of global (total), direct and diffuse(scattered) radiation on horizontal surface on location
Energy density H in [Wh/sqm]
direct
diffuse
Scattered
Direct
Global
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

12. Option 2: Use analytic data from available measurements data bases
Examples:
European Centre for Medium Range Weather Forecast
NASA Surface Meteorology and Solar Energy ( )
Most compresensive and recent from Joint Research Centre (IET) of EU:
Photovoltaic Geographical Information System (PVGIS) with 1-2 km resolution, public and available on:
Sufficient for basic preliminary analysis and Sun radiation potentials calculation
More detailed for Croatia: Energy Institute Hrvoje Požar: Zdeslav Matić: “Sun Radiation on Area of Republic of Croatia – Handbook for Energy Usage of Sun Radiation”, 2007
In REGPHOSYS PV system installed at ETFOS mesurements of Sun Radiation intensity (and cell temperature) will be available
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

13. PVGIS map of Croatia

14. PVGIS map of Hungary

15. Example of Sun radiation estimation
in PVGIS, August,Osijek
Fixed system, 33o (annual optimum for OS)
“Sunflower” in 2 axes
(25-40% more energy)
Photovoltaic Systems as Actuators
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REG-PHOSYS

16. Example of daily radiation and optimal angle estimation
in PVGIS, by months for Osijek
Optimal angle for OS during entire year is 33o
Average daily radiation by months for OS
Optimal angle by months for OS
Mar 43o, Jun 12o, Sep 41o, Dec 62o
Photovoltaic Systems as Actuators
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18. Photon energy: E = h·ν where
Photovoltaic effect
Direct transformation of Sun light (radiation) in electric energy (electricity).
Sun light (radiation) consists of photons (particles containing different amounts of energy related to different wave lenghts of solar spectrum.
Photon energy: E = h·ν where
h is Planck constant = 6.625·10-34 Js v photon frequency (inversly proportional to wave lenght)
When photons hit the PV cells (p-n layer of semiconductor) they can be reflected, pass directly through the cell or be apsorbed in the cell.
Only those photons apsorbed results in energy needed to free the electrons and hence produce electricity (photovoltaic effect).
Teorethical efficiency max. 33% (losses due to semiconductor characteristics 23%, PV cell response 31%, limitation of cell voltage up to 0.8V 12%, thermodynamic losses 3%).
Photovoltaic Systems as Actuators
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19. Spectral distribution of solar radiation and solar cell response
ULTRAVIOLET
INFRARED
Solarn radiation W/m2,m
Wave lenght m
Photovoltaic Systems as Actuators
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20. Similar to batteries (but mostly constant current source)
Special preparation of n-layer surface of the PV cell results in electrons (negative charges) moving there naturally.
By leaving their position in the p-layer the holes are being created as positive charges.
Imbalance of negative charges of n-layer surface and positive charges of p-layer surface = voltage (potential).
When connected with outer circuit (through load) free electrons starts to flow (current).
Similar to batteries (but mostly constant current source)
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

21. Basic structure of PV cell
Photovoltaic Systems as Actuators
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22. PV cell technologies comparison
Photovoltaic Systems as Actuators
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23. PV technologies – price vs efficiency
Photovoltaic Systems as Actuators
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24. PV from cell to system (cell, module/panel, array, system)
PV cell is basic part of PV system. Individual cells vary from cm.
One cell produces only 1-2 W, with max. voltage of 0,6-0.7 V, insufficient in most uses: they are being connected electrocally to form module/panel:serial-paralel junction of cells protected from athmosperic influences.
Modules are further connected to arrays (serial-paralel junction of modules) from several up to thousands (depending on the size of the system).
PV system: overall electricity production facility (power plant).
PV array
Photovoltaic Systems as Actuators
of Regional Development
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25. Current/voltage characteristic
Electrical characteristics of PV cells (and modules)
PV cell current
Open ciruict voltage
Diode current
Current/voltage characteristic
Short cicuit current = Photo (light) current
Photovoltaic Systems as Actuators
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26. Serial junction of modules: Increase of voltage and power
Modularity of PV arrays (of modules)
Modular characteristic of PV enabling gradual increase in power
Serial junction of modules:
Increase of voltage and power
with constant current.
Paralel junction of modules:
Increase of current and power
with constant voltage.
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

27. Influence of sun radiation Influence of temperature
Electrical performance of PV cells and modules
Influence of sun radiation
Influence of temperature
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

28. Integrated set of PV modules (arrays) and other components:
PV systems
Integrated set of PV modules (arrays) and other components:
- structure for installation
- maximal power tracker and other devices for regulation
- storage components (batteries, chargers...)
- DC/AC converters (inverters)
- cables, connectors , etc.
General types:
1. Off-grid PV systems for individual production and use of electricity (rural areas, space programs, traffic signals…)
2. On-grid PV systems usually installed (on the roofs or ground, small to large scale)for selling electricity to the network with incentive (priviledged) tarriff prices (most of the PV systems today)
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

29. PV SYSTEMS OFF grid ON grid
Without energy storage
With energy storage
Hybrid systems
Directly on grid (with inverters and measurement point)
With wind generator
With inverters
Connected to the public grid through the installation facility (connecting line, transformer station…)
With fuel cells
Without inverters
With fuel generator
Photovoltaic Systems as Actuators
of Regional Development
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30. Comparison of PV system development Europe/rural
Photovoltaic Systems as Actuators
of Regional Development
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31. On-grid PV system in pricipal
Photovoltaic Systems as Actuators
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32. On-grid PV system electric scheme
Photovoltaic Systems as Actuators
of Regional Development
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33. Off-grid PV system in principal
Photovoltaic Systems as Actuators
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34. PV systems integrated tobussiness building
Coincidence of intensity of PV production and bussines building consumption
Doxford Int. PLC ured: First commercial building with integrated PV system
Passive building Vienna, Austria

35. Centralized large - scale PV power plants
Example: Agua Caliente Solar Project First Solar, Inc.
290 MW ( )
modules on ground (non-integrated)
tCO2-equ./yr ( cars)
400 jobs on construction site
Source: Agua-Caliente-Solar-Project

36. Power Plants Technologies and Economics
Levelised Cost of Electricity (LCOE) 2008.!!!
Source: IEA/NEA Projected Cost of Generating Electricity 2010
Wind electricity is coming to commerical. Load factor of only 26% + wind speed variation - major power system stability problem!
Solar PV (Photo-Voltaic) electricity still needs HUGE incentives. Load factor 13% + efficiency up to 16% - major electricity market competitiveness problem.
Photovoltaic Systems as Actuators
of Regional Development
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37. PV modula prices [USD/W]
PV modules specific investments, 2011.
In EUR/W or USD/W
In average 50% of on-grid PV systems
PV modules in avg: 1,38 US$ (1,07 €/W) (pad od 50% drop 2010./2011.,20% od 2009./2010.)
PV modula prices [USD/W]
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

38. Specifiv investment costs of FN systems, 2011.
On-grid, in average: 2,6-4,4 $/W (2,0 - 3,4 €/W), cabels,converter, measurements, control)
Off-grid, in average: 3,7 -7,2 $/W (2,9-5,6 €/W) additional: batteries and chargers)

39. Convertes for PV applications
Converter is a critical component, converting DC to AC current, supplying the load or connecting to the network.
Currently, most products are focused to PV systems on houses and buildings. Typicall rated power: 1 do 10 kW. Single-phase connection in Europe, three-phase in USA.
Last years significant increas in rated power of DC/AC inverters, typically : 10, 30 i 100 kW instaled in three-phase connection. Sbut even up to 2 MW (particularlly in Spain, Italy and USA) for large-scale ground PV power plants.
Increased production resulted in continuous decreas in specific investment costs: from 0,20 €/W for larger to 0,50 €/W for smaller units.
Photovoltaic Systems as Actuators
of Regional Development
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40. Cables and constructions
Part of the investment costs other than capital equipment are content-related equipment construction structure, cables, cable connectors and wiring box.
In pricipal, such costs could be elaborated and costs assessed only after the general project.
Typical speciffic costs of this auxilliary equipment ranges between 0,20 - 0,40 €/W depending on the size of the PV system.
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS

41. Investicijski troškovi Tipična cijena energije
Characteristics, investment costs and price of electricity from PV systems
Dramatic increase in PV system installation (2005./ %), economic crisis, limitations in incetive schemes for PV resulted in strong drop of specific investment costs. The price of electricity from PV still very high.
Proizvodnja električne energije
Tipične
karakteristike
Investicijski troškovi
(€/kW)
Tipična cijena energije
(€cent/kWh)
FN sustavi na mreži
integrirani
(na krovovima kuća/zgrada…)
Vršna snaga:
3-5 kW (domaćinstva)
100 kW (komercijalno)
500 kW (industrija)
Iskorištenje vršne snage: 12-20%
17, ,0 (Europa)
FN sustavi na mreži neintegrirani
(na tlu, FN elektrane)
Vršna snaga: MW
Iskorištenje vršne snage: 15-27%
15,5 – 28,6 (Europa)
1 USD (2011) = EUR
Source: REN21 Renewable 2012 Global Status Report

42. Power Plants Technologies and Economics
Source: European Commission – “ExternE Project”: External Costs, Research results on socio-environmental damages due to electricity and transport”, 2003.

43. Power Plants Technologies and Economics
External (Environmetal) Costs - Germany

44. Instaled capacities in PV systems 2011 only IEA PVPS countries
Source: IEA Photovoltaic Power System Programme, Task 8: Trends in PhotoVoltaic Application, 2011
Currently (different to world global REN21) total of 63,6 GW, out of which 28,0 GW instaled during 2011 (INCREASE OF 78%TO 2010!)
On-grid: 62,4 GW, Off-grid: 1,2 GW (only 1.9%)
Instalirana snaga [MW]
u zemljama IEA PVPS

45. Instaled capacities in PV systems 2011
in [MW]
Only IEA PVPS countries

46. Largets producers of PV modules and cells 2011 in IEA PVPS countries
PV module market share in IEA PVPS countries
Total: 34 GW in 2011
30 GW wafer-based p-n junction
3,9 GW thin-film – increase in last 4 years
PV cells produced in PVPS countries in 2011 in [MW]
Total: 29,9 GW (Philipines, Singapur, India… misssing)

47. Global PV system market 2011
Total instaled: 70 GWe
Increase 2011: 74%
Increase 2006/2011: 58%
PV cell production
(top 15)
Total:
> 40 GWe
Source: REN21 Renewable 2012 Global Status Report

48. Example of investment costs (2013) for 10 kW PV Power plant in Croatia
PV-Moduls 0,65-0,75€/W ( HUF/W)
AC/DC Inverters ~ 0,24-0,30€/W ( HUF/W)
Construction structure ~ 0,12-0,17 €/W (36-51 HUF/W)
Electrical equipment, cable, connectors,...~ 0,25-0,30€/W (75-90 HUF/W)
Electrical projects and necessary permits ~2000€ ( HUF/W)
Electrical work ~1000 € (0,10 €/W)
Measurement of power quality~1000€ (0,10 €/W)
Other expenses (electrical testing, ...) ~ 1000€ (0,10 €/W)
Total investment: app € ( HUF) + insurance and taxes
Specific investment: app 1,85 €/W (558 HUF/W) + insurance and taxes

49. Current incentive tariffs for solar (PV) power plant in Croatia
0,42 €/kWh
0,32 €/kWh
0,22 €/kWh

50. 10 kW PV electr. production estimation
for Osijek in PVGIS

51. Cost/benefit analysis of 10 kW PV for Osijek (and Novi Sad, SRB)
Investment:
16.400,00
EUR
Equity:
Own interest rate:
8,00%
Interest rate of Own share
0,00%
NPV:
34.079,52
IRR Operative Income:
21,89%
IRR Cash Flow:
20,98%
NPV Equity
56.783,13
Difference NPV - Equity:
40.383,13
Difference NPV - Investment
17.679,52

52. Technical and Economic Characteristics
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS
PHOTOVOLTAIC SYSTEMS
Technical and Economic Characteristics
Prof.dr.sc. Damir Šljivac
Josip Juraj Strossmayer University of Osijek, Croatia
Faculty of Electrical Engineering
Department of Power Engineering
phone:
Photovoltaic Systems as Actuators
of Regional Development
REG-PHOSYS