THE PHOTOVOLTAIC
TECHNOLOGY
Ing. S. Castello
castello@casaccia.enea.it
ENEA, Renewable Sources Sector
July 2006
SUMMARY
• PV plants features
• Applications
– Stand alone plants
– Grid connected systems and Distributed
generation
• Demonstrative projects
• Tracking and concentrating systems
• Market
• PV industry
• Plant and kWh costs
• Diffusion programmes
PV TECHNOLOGY
The technology is relatively recent:
• Foundation was laid in the early 50’: first modern c-Si
cell discovery (Bell Telephone Laboratories)
• 1958: first application successful used in space
(Vanguard I)
• late 70’: starting of terrestrial application and
development of market.
From then on the technology has shown a steady
progress, the costs have recorded a constant reduction
but remain still high in comparison to the other
renewable sources
PV ENERGY ADVANTAGES
• Use of an inexhaustible and free fuel
• Environmentally friendly
• Good reliability, higher than wind turbines or diesel
– lasts more than 30 years
– low maintenance cost
• Fully automated operation
• Low risk
– capital intensive but low O&M costs
• Modularity
– the required power is obtained using a number of the same
building blocks
• Exploitation of not utilized surfaces capability
– PV can be mounted on roofs, integrated in building skin or
installed in marginal areas (deserts)
THE PV PLANTS
• Systems able to collect and convert light into useful
electricity to be delivered to specific appliances or into
the electric grid
• 2 main categories
– Stand-alone: to supply isolated users (from
consumer to decentralized rural electrification)
– Grid-connected: to fed power to the electric grid
(from small roofs to power stations)
• plant components
– PV array and power conditioning unit (PCU) or
– modules and balance of system (BOS)
THE COMPONENTS
• PV array (Pnom, Vw)
– A number of PV modules
– Cables and protection devices
– Structure (to support and to expose the module for maximum
light capture)
• PCU
– Stand-alone plants
• Matches the array output to the load requirements
• Manages the storage system
– Grid-connected plants
• Convert the dc array output to standard ac power
• Fit the PV array output to the grid (MPPT)
• Control the quality of the energy supplied to the grid
(distortion and power factor correction)
THE COMPONENTS
• PV modules
– The smallest electrical unit of PV plants, formed with solar cells
• assembled in series/parallel configuration
• encapsulated
– Mechanical and corrosive protection of cells and their
interconnection (long operation life)
– Electrical isolation of the voltages generated
• material used for encapsulation: glass tempered glass or plastic
• frame: metal or plastic
– features required
• ultraviolet stability
• tolerance to temperature and heat dissipation ability
• self cleaning ability
THE COMPONENTS
• BOS
– Cabling
– Switching and protection devices
– Battery
– Charge controller
– Dc/ac inverter
– Module supporting structures
– Engineering
– Labour to install a turn-key system
STAND ALONE PLANTS
• When well suited:
– Remote site far from the grid
– Maintenance and fuel expensive (transport)
– Reliability is paramount (tlc, signaling)
– Simplicity required (remote houses, schools)
– Transportability (navigation laps, laptop computers)
– Intermittent power acceptable (fans, pumps)
– Noise and pollution-sensitive environments (parks)
– Reducing fuel consumption (small grids)
STAND ALONE PLANTS
• Already competitive with diesel generator for load
lower than few kWh/day
• Preferred option for high value applications
• Key technology for off-grid application, but further
decrease of cost is essential to facilitate their use
• Costs higher then grid connected systems (batteries)
but already with its own nicks market
• Applications:
– Domestic
– Industrial
– Electrification in Developing Countries
DOMESTIC APPLICATIONS
•
Remote users (economic alternative to utility grid at distance > 1 – 2 km)
– Rural electrification (0,5 – 1,5 kW). light, refrigeration and other low power
loads
– Lighting of isolated areas with PV lamps (100 W) or centralized systems (110kW)
•
Consumer
– Watches, calculators (mW), lamps (10 W)
INDUSTRIAL APPLICATIONS
• First terrestrial high value applications (PV costs negligible in
comparison to the service provided)
• Competitive with other small generating systems
– Telecommunication
0,5 – 10 kW
– Cathodic protection
0,5 – 5 kW
– Signaling and data acquisition
0,1 – 1 kW
– Park-meter or Emergency telephones (highway) 10 – 20 W
ELECTRIFICATION IN DEVELOPING COUNTRIES
• 1.7 billion people is aimed to:
– Basic needs: refrigeration and lighting for sanitary use, potable water
– Quality of live improvement: lighting in houses streets and schools,
telephone, radio and TV services
– Small scale economic development: water for irrigation and livestock,
motorization for small craft and mills
IEA Source
SMALL STAND ALONE PLANTS
CHARGE
CONTROLLER
PV MODULES
DC LOADS
BATTERY
REMOTE DWELLINGS
DC LOADS
PV
GENERATOR
GENERATOR
CHARGE
CONTROLLER
BATTERY
DC/AC
INVERTER
COMMERCIAL
AC LOADS
VILLAGE ELECTRIFICATION
PV
GENERATOR
GENERATORE
CHARGE
CONTROLLER
BATTERY
DC/AC
INVERTER
RECTIFIER
LOADS
DIESEL
WATER PUMPING
PV
GENERATOR
GENERATORE
PV
GENERATOR
GENERATORE
DC/AC
INVERTER
(FREQUENCY
VARIABLE)
DC PUMP
PUMP
(CENTRIFUGAL
OR
RECIPROCATING)
WATER
TANK
CATTLE
WATERING
TANK
SPRINK
GRID CONNECTED SYSTEMS
• Not competitive yet, but potentially able to make a substantial contribution
to sustainable electricity production in industrialized countries.
• Applications:
– Diffuse generation
– Power stations
– Grid support (weak feeder lines)
– Small grid support (islands)
PV
GENERATORE
1 – 50 kW
> 1 MW
0,5 – 2 MW
100 – 500 kW
DC/AC
INVERTER
LOADS
GRID
GRID CONNECTED PLANT
GRID
PV MODULES
INVERTER
DOUBLE
COUNTER
COMMERCIAL AC LOADS
DISTRIBUTED GENERATION
• Small size plants (1 – 50 kW) connected to the LV grid (without battery)
• Suited to be installed on buildings or other infrastructures (absence of
noise, moving parts, emissions)
• Huge potential: south oriented roofs covered with PV could supply
electricity needs in many countries.
• PV energy cost: still double with respect to the electricity cost paid by
users
DISTRIBUTED GENERATION
ADVANTAGES
– Distributed exploitation of a diffused source
– Production at the place of utilization (transmission
losses avoided)
– Easy grid connection (battery)
– User contribution in technology diffusion
– Promotion of energy saving and more efficient
appliance
– Exploitation of not utilized surfaces
– Positive architectural valence in the urban contest
– Possibility to combine energy production with building
envelop functions (saving of traditional building
components)
DISTRIBUTED GENERATION IN ITALY
• First installations realised and monitored by ENEA and
ENEL (preliminary actions of the Italian Roof-top
Programme)
• Aims
– to check how proper the identified technical solution
were
– to test new components and new design criteria
– set up the monitoring network
• Site: Major Italian Universities and Municipalities
• In operation since 1999
• Long term performance analysis in progress
• Typical plant size: 2 - 3 kW
• Applications: roof integration, façade, sunshade
DISTRIBUTED GENERATION
SOUND BARRIERS
• Marginal spaces utilization
• Use of noise barrier as
supporting structure
• Use of PV module as noise
barrier element
• Zig-zag structures to combine
noise absorption and production
maximization
• Bifacial modules in north-south
highway direction
IEA source
POWER STATIONS
– Typically from hundreds kW to several MW
• Based on flat plate, tracking structures or concentration systems
• To be utilized for electricity feeding into the grid
• Hydrogen production (in future)
• Electricity cost still high 20 – 40 c€/kWh with respect to the one of
conventional electricity (2 – 6 c€/kWh, depending on externalities)
GRID SUPPORT
– Large size distribution grids
• Medium size systems (0,5 – 2 MW) to strength weak feeder
– Small grids (few MW) of small islands (33 in Italy)
• small – medium size plants (100 – 500 kW) to provide a
significant contribution (10-30%) to energy production
– Almost cost effective
– Fuel saving
– Respect of environmental constraints
DEMONSTRATION PLANTS
IN ITALY
• Promoted by ENEA, ENEL, PV Industry, Municipalities
• Major projects
– PLUG (ENEA)
– Serre (ENEL)
– Vasto (ANIT)
• First prototypes in operation since 1984 (long term
performance analysys still ongoing)
• Typical power: 10 kW – 3 MW
• Application: Power stations (0.6-3.3 MW), Small grid
support (200 kW), Water punping (70 kW), Desalination
(100 kW), Cold store (45 kW)
PLANT
LOCATION
LOCATION
OF SOME
DEMO PLANTS
Zambelli, 70 kW
Water pumping
Casaccia, 100 kW
Car parking
Leonori, 86 kW
Car parkig
Giglio, 450 kW
Cold store
Altanurra, 100 kW
Grid-connected
Carloforte, 600 kW
PV-Wind
Vasto, 1000 kW
Power station
Delphos, 600 kW
Power station
Serre, 3300 kW
Power station
Vulcano, 180 kW
Grid support
Mandatoriccio, 216 kW
Grid-connected
Lamezia, 600 kW
PV-Wind
PLUG PROJECT
• Development of a 100 kW standard plant for medium size applications
• Aim: cost minimization
– Standardization and preassembling of components
– Modular architecture of systems
– Civil works absence
• Applications
– Casaccia
(preexisting structures exploitation)
– Delphos
(modular concept)
– Alta Nurra
(combined use of PV and wind)
– Vulcano
(high penetration of PV in small grid)
SERRE PROJECT
Development of a modular segment to be used in large size plants
operated by Utilities
• Objectives
– Verify of the projectual criteria adopted
– Evaluation of scale effects on costs
• Application
– Serre plant: 9 fixed units + 1 tracking unit (horizontal north-south axes)
ANIT PROJECT
• Development of large grid connected and hybrid systems
• Aim
– gather experience in design, construction and operation on large
scale PV plants
– verify the degree of availability
• Applications
– Vasto plant
2 segments of 500 kW
– Carloforte
2 x 300 kW PV + 3 x 320 kW Wind
– Lamezia
2 x 300 kW PV + 3 x 320 kW Wind
ENVIRONMENTAL IMPACT
•
Negligible pollution during plant operation:
– Chemical: total absence of fumes or emissions (COx, SOx NOx)
– Thermal: maximum temperatures < 60°C
– Acoustic and electromagnetic : acceptable (if inverter within norm limits
are adopted)
•
Complete absence of:
– moving parts
– waste (components can be recycled)
– radiation or scories
– circulation of high temperature or pressure fluids
•
Emission comparison
– PV
30 gCO2 /kWh
– Gas
400 gCO2 /kWh
– Oil
800 gCO2 /kWh
•
CO2 emission avoided = emission avoided for electricity production –
emissions related to the construction of the PV plant
ENERGY PAY BACK TIME
PROCESS PHASES
m-si wafer production
Modules Cells formation
BOS
ENERGETIC OCCURRENCE
kWh/m2
175
400
Module assembly
45
Supporting structures
50
Cabling + inverter
30
Transport + installation + operation +
decommissioning
200
TOTAL OCCURRENCE
900
YEARLY ENERGY PRODUCTION
190
EPBT = Total occurrence/yearly E.P.
4.7 years
FUEL SAVING
•
•
•
•
•
•
•
Plant life time
Energy pay back time
Plant useful life
Yearly energy production
Energy produced in 25 years
1 kg of fuel
Fuel saving
• CO2/kWh
• Emissions avoided
30 years
5 years
25 years
1 300 kWh/kW
32 500 kWh/kW
4 kWhe
8 000 kg/kW
0.77 kg
25 000 kg/kW
MODULE EFFICIENCY DEGRADATION
Experience conducted by ENEA on 80
modules installed in 1980
Results:
Declared efficiency
Measured efficiency
- at acceptance tests:
- after 11 years:
- after 25 years:
9,54%, (-10%)
9,14%.
8,6%.
Efficiency degradation:
Mean degradation rate:
10% in 25 years
0,4% /year
10,6%
MODULE FAILURES
Defects detected
after 25 years don’t
have caused further
efficiency
degradation with
respect to the natural
degradation
(0,4%/year)
Tedlar detachment or delamination
module browning
Tedlar leak
This experience
demonstrate that the
life time of “old
generation”, “glasstedlar” can be
considered around
30 years.
Grid oxidation
ARRAY DEGRADATION
• Array degradation factors
– Natural degradation
• power degradation
• life-limiting wear-out
• BOS component failures
– Accidental degradation
• due to single-module failure (which does not involve failures of
entire strings)
• data on efficiency and module failures have been collected for many
years from 2 arrays (at ENEA research centre)
• the influence of module failure on efficiency degradation was found to
be very low if module failure occurs at rate <0.1 %/year
• In this case module replacing could be not urgent
– especially in BIPV or remote systems
– unless the module failure (such as low-insulation loss) cause
chained failure of entire strings
PLANT EFFICIENCY DEGRADATION
PR
1,000
0,800
0,200
0,000
Jan
1992
Jan
1993
Jan
1994
Jan
1995
Inverter failure
0,400
string failure
Inverter failure
0,600
Jan
1996
Jan
1997
Jan
1998
Jan
1999
Jan
2000
Jan
2001
plant efficiency (%)
10
8
6
4
2
0
5
Inverter substitution
failure
(PVgen or inverter)
TIPICAL SEQUECE OF EVENTS
14
12
0
10
15
20
Years
25
30
35
IMPACT ON LAND
• Land occupation
– Plant power
– Yearly energy production
– Domestic users supplied
– Land required
• Energy consumption in Italy
1 MW
1.300 MWh
600 (in Italy)
1.5 hectares
300 millions of MWh
(land required: 3.000 km2)
• Possibility of using marginal lands or not utilzed areas (20.000 km2
in Italy)
• Integration into existing structures
PV POTENTIAL
• Total amount of solar energy on earth surface: 15 thousand times
the world energy consumption
• Technical potential: 4 times the world energy consumption
– Unrealistic due the mismatch generation/demand
– Unless PV energy utilized for H2 production (in future)
• South oriented roofs in Europe: electricity needs in Europe
PV AND ARCHITECTURE
• Typologies integrated into architectural structures
– Roofs (sloped, horizontal, curved)
– Facades
– Sun shadings (fixed and mobile)
– Glass roofs and curtains
– Covering elements
– Balustrade
• Typologies integrate into urban infrastructures
– shelters (car, bus stop, train station)
– Industrial buildings
– Noise barriers
BIFACIAL MODULES
- applications with
architectural constraints
- solar radiation
exploitation on both
sides of module
- larger energy
production (>10-20%)
with respect to standard
modules
- ease maintenance
against snow, dust and
bird dropping
TRACKING SYSTEMS
ONE AXIS TRACKING FLAT PLATE
ONE AXIS TRACKING
Incident
energy > 20%25% with
respect to fixed
plated
Fixed flat plate
(tilt = latitude)
north-south
axis tracking
flat plate
Tilt=latit
ude
TWO AXIS TRACKING
TWO AXIS TRACKING
Sistema piano
Incident
energy
ad
> inseguimento
30%- 35%
with
respect
su due
assito
fixed plated
Fixed
plate
Tiltflat
= latitudine
(tilt = latitude)
2 axis
tracking
flat plate
STRUCTURES COMPARISON
• FIXED
– No maintenance
– Simple mounting and
transport
– content cost
– Modest foundations
– Less energy collected
– modest aesthetical
result
• TRACKING
– Maintenance necessity
– Exacting transport and
installation
– Higher costs
– Larger areas required
– More energy collected
– Harmonious
aesthetical result
CONCENTRATING PV
• PV material (high cost), is partially substituted with mirrors or
lenses (lower cost)
Solar radiation
Solar radiation
Lens
PV cell
PV cell
• The efficiency of cells is higher (30% - 40%)
– high concentration factors: 100X – 1.000X (Irr*logIrr)
– smaller cells
CONCENTRATING PV
The incident energy is
almost the same with
respect to fixed plates
systems:
only the direct
component of light is
exploited
Concentrating
system
Fixed flat plate
(tilt = latitude)
CONCENTRATOR MODULES
- Concentration factor: 100X –
400X
- Lens efficiency: 80% - 85%
- cell cooling difficulty
- Inexpensive polymer lens
- lifetime not verified
CONCENTRATORS
Central tower
Dishes
Trough system
- Concentration factor: 1.000X
- Mirror efficiency: 85% - 92%
- currently high costs
- Cooling challenge
PHOCUS PROJECT
(PV Concentrators for Utility Scale)
– Aim: assessment of technical and economical feasibility of PV
concentration for centralised generation
– Ongoing activities
• Optimisation of the most appropriate technologies for solar
cells, optical devices, concentrator modules, tracking system
• Development of a 5 kW standard unit
– c-Si cells optimised at 100-400 suns
– refractive prismatic lenses
• Experimentation on 5 units
– Planned activities
• Development of high efficiency cells
• Investigation on optical devices based on Fresnel lenses and
Compound Parabolic Concentrators
CONCENTRATOR MODULE
Optical system
(prismatic
lenses)
Structure with
separators
PV cells
Heat sink
IEA-TASK 2 PERFORMANCE DATABASE
• Contains information on the technical performance, reliability and
costs of 431 monitored PV plants located worldwide. Germany
(118), Japan (95), Switzerland (64), Italy (35), France (31),…
• Applications: Stand alone, hybrids, grid connected
• Plant size: from 1 to 3300 kW
• Mounting typologies: facades, flat and sloped roofs, integrated
roofs, sound barriers, free-standing
• Performance data collected from 1986 (Japan)
IEA-TASK 2 PERFORMANCE DATABASE
• For each plant provide
– General information
– Component data and system configuration
– Data collected (Irr, Pdc, Pac,..)
– Costs
– Calculated data (index of performance)
• The user can
– select PV system, present monitoring data, calculated results
– export these data into spreadsheet programs
– check the operational behavior of existing PV plants
– get a report on performance results
• Can be downloaded from www.iea-pvps-task2.org
IEA source
EFFICIENCIES AND COSTS
0,9
8
0,8
6
0,7
4
0,6
Vulc1 Delp1 Casac Delp2 Vasto Serre Altan
84
85
91
91
93
94
96
inverter efficiency
efficiency (%)
94
92
90
88
Specific costs (Euro/Wp)
10
mean eff. /
nominal eff.
efficiency (%)
PV genearator efficiency
25
Costs
20
module
15
10
5
0
Vulc1
86
84
82
Vulc1
Delp1
Casac
Delp2
Vasto
Serre
Altan
plant
Delp1 Casac Delp2 Vasto Serre
Altan
5
4
3
Ls
2
Lc
1
Yf
0
Performance
ratio
1992
1993
1994
1995
1996
1997
1998
1999
2000
0,8
100
80
60
40
20
0
0,6
0,4
0,2
0
1992 1993 1994 1995 1996 1997 1998 1999 2000
Availability (%)
Yield and losses (h/d)
INDICES OF PERFORMANCE
GLOBAL ECONOMIC SURVEY
• aimed to collect worldwide:
– Costs of systems, components, maintenance (during their life
cycle)
– Production data and maintenance information
• will allow to:
– compare costs of system for different markets in different
countries as well as different sizes of installations
– know the true LCA
– predict performance life expectancy, mean time between
failure and costs to service and replace parts
• accessible on http://iea.tnc.ch
IEA source
INSTALLED POWER
- IEA countries: 2.8 GW
- Total: 3.3 GW
3500
- 1.2 MW in 2004
- Growth rate: 42%
2500
2000
IEA
countries
1500
1000
500
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
IEA source
1993
0
1992
- applications: 70% of
small grid connected
systems
Grid-connected centralised
Grid-connected distributed
Off-grid non-domestic
Off-grid domestic
3000
MW
- Projections for 2005:
4,5 GW
Worldwide
CUMULATIVE POWER IN THE COUNTRIES
(end 2004)
1132
1200
94% in JPN, USA and
DEU
1000
794
MW
800
600
365
400
200
52 19 13 23
49
10 18
6,9
39 26,30 8,2 31
USA
NOR
NLD
MEX
KOR
JPN
ITA
GBR
FRA
ESP
DEU
CHE
CAN
AUT
IEA source
AUS
0
Impact of market support
in terms of installed
capacity per capita:
- DEU: 10 W/c
- JPN: 9 W/c
- CHE: 3 W/c
- NLD: 3 W/c
- ITA: 0,5 W/c
TRENDS IN SOME COUNTRIES
400
Annual rate growth:
JPN
350
installed power (MW)
DEU
300
- DEU: 137%
Sustained by feed-in
tariffs (0.5 €/kWh)
USA
NLD
250
AUS
200
FRA
150
AUT
- constant in JPN: 22%,
net metering at 0.2
€/kWh + low subsidy
on capital costs (10%)
ITA
100
50
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
IEA source
1993
0
Grid-connected centralized
Grid-connected distributed
Off-grid non-domestic
Off-grid domestic
- PV roofs : CHE, DEU,
GBR, JPN, NLD
100%
- Vacation cottages: SWE
NOR, FIN
80%
60%
-Rural electrification:
MEX, FRA
40%
- Commercial applications:
USA e AUS
20%
USA
SWE
PRT
NLD
MEX
KOR
JPN
ITA
ISR
GBR
FRA
FIN
DEU
DNK
CHE
CAN
NOR
IEA source
AUT
0%
AUS
Installed power by application (%)
DISTRIBUTION OF APPLICATIONAS
PV SYSTEM MARKET IN ITALY
Primary applications
• Off Grid domestic: 5,3 MW
– rural electrification (5000 isolated households promoted
through 80% incentives in the early 80’)
– lighting
• Economic industrial applications: 7 MW
– telecommunication
– signaling
– cathodic protection
• Demonstration (sharply increasing in the 90’): 6,7 MW
• Distributed generation, growing over the last year (rooftop
Programme): 17 MW
• TOTAL: 36 MW
CUMULATIVE POWER IN ITALY
40
on-grid distributed
on-grid centralised
30
off-grid domestic
25
off-grid industrial
Rooftop
Programme
Demonstartion
Projects (UE)
20
15
10
Law 308: rural
electrification
5
2004
2002
2000
1998
1996
1994
1992
1990
1988
1986
0
1984
installed power (MW)
35
INDUSTRIAL PRODUCTION
Module production (MW)
1400
1200
1000
Module production
Production capacity
800
600
400
200
0
IEA source
1993 1994 1995 1995 1997 1998 1999 2000 2001 2002 2003 2004
INDUSTRIAL PRODUCTION
• World module production in 2004 : 1200 MW (700 in 2003). Only
IEA countries: 1070 MW
• Average growth : 60%
– JPN: 70 % (50% of the world production)
– DEU: 66% (second producer)
– CHI: 400% (100 MW in 2004)
– ESP: second producer in Europe
– FRA and ITA: continue to lose market shares
• Production capacity growth: 17%
– DEU: awaited expansion not fulfilled yet
– USA: capacity reduction (abroad production)
MODULE PRODUCTION BY REGIONS
(year 2004)
module production (MW)
700
Other
a-Si
c-Si
600
500
400
300
200
100
0
Japan
IEA source
USA
Europe
Rest
THE PV INDUSTRY STRUCTURE
Producers:
– ingots and wafers
• USA (4 companies + Elken based in NOR): 5100 t
• DEU (Wacker): 2800 t
• JPN (Tokuyama) : 1000 t
– cells and modules
• C-Si: 850 MW
• a-Si: 40 MW
• Others: 280 MW
– BOS components (inverter)
• EU: 30 companies (SMA)
• USA and JPN: 20 companies (Xantrex, Sharp)
THE PV INDUSTRY STRUCTURE
– Vertically integrated companies (from ingots to cells)
• Kyocera (JPN), BP Solar, Shell Solar, Photowatt
– Company attempting to commercialize new processes
• Silicon ribbon: RWE Schott
• String ribbon: Evergreen Solar
• Micro spherical silicon tech.: Canadian Spheral Solar Power
• Silver cells: Australia Origin Energy
Module production (MW/year)
400
350
300
250
200
150
100
50
0
BP Solar
Q cell
SOLON AG,
Shell Solar
Solarwatt
Solara AG
Alfasolar
Flabeg Solar
GSS GmbH
S.M.D. SolarAnTec Solar
Isofoton
BP Solar
Atersa
Photowatt
ICP
Helios
Eurosolare
Sharp
Kyocera
MSK
Sanyo
Mitsubishi
Kaneka
Showa Shell
Shell Solar
Shell Solar
GPV
Artic Solar
Shell Solar
BP Solar
AstroPower
RWE Schott
United Solar
MODULE MANUFACTURERS
AU
DEU
ESP
F GB IT
JPN
NL P SW
USA
ITALIAN PV INDUSTRY
• 2 major module manufacturer
– Enitecnologie (ENI, Italy’s oil and gas giant)
• Mono and multi-crystalline silicon cell and module production
• Production capacity: 9 MW/year (4.2 MW last year)
– Helios Technology
• Fabrication of cells and modules from mono-crystalline silicon
wafers
• Production capacity: 10 MW/year (7 MW last year)
• Some small companies assembling and encapsulating tailor-made
modules (facades, windows, coloured cells). Capacity: 10 MW/y
• 5 companies manufacturing small and medium size inverters, for
on-grid and off-grid applications
• 100 specialist PV companies offering consultancy, design,
installation services and component delivery (some of them
constituting “GIFI”, the Italian PV Firm Group)
TECHNOLOGY PRODUCTION
100%
80%
60%
other
p-Si
a-Si
40%
c-Si
20%
0%
1998
1999
2000
2001
2002
2003
2004
- Limited availability of C-Si feedstock (electronic industry):
- necessity of a specific production: solar grade silicon
- increase of a-Si market share (has remained at a modest level from 5% to 15%)
- Material reduction (Si utilization is still relatively low) and efficiency increase
- Concentration (use small area, high efficiency cells)
PV INDUSTRY
• Actions to be taken:
– Development of a sustainable market driven by incentives
(implementation of deployment measures)
– Rules clear and appropriate (overcome barriers related to
regulations, standards, safety)
– budget adequate for R&D and activities coordination
– Strengthen joint initiatives between research and industry
– Adopt instruments to encourage investment
– Promote BIPV through the development of PV components to be
used in buildings
– Ensure the Si availability matter at acceptable costs
– Optimize the recycling process
– Cooperation with other high tech sectors (flat panel display, micro
electronics, nanotechnologies
MARKET EXPECTATION
STUDY COMPARISON
2000
module production (MW)
1800
1600
Bayer (15%) Growth rate)
Kyocera (18%)
Strategies Unlimited (23%)
1400
1200
1000
800
+60%
+40%
600
400
200
0
2000
2002
2004
2006
year
2008
2010
MODULE PRICES EVOLUTION
(€/W)
20
15
10
5
- Modules prices 3.5 €/W
- Module prices increased:
- tightening of Si supply
- more order in the books of
manufacturers than they could
fill in
19
11,3
7
5
3,2 3,2
1,4
0
1970 1980 1990 2000 2010 2020
year
- Cost reduction (to 1.5-2 €/ in 2010)
can be achieved by
- market growth (scale effect)
- research efforts (new materials,
manufacturing process
optimization)
LEARNING CURVE OF MODULES
- Historic learning curve shows a
18% cost decrease for every
doubling of the cumulative
installed power
- The cumulated power has
doubled 4 times in the last 10
years (prices reduction: 70%)
Prices of modules (€/W)
10
2000
c-Si
2010
1
thin film
2020
Growth rate in the past: 20%
0,1
0,1
1
10
Cumulated power (GW)
100
1000
- The learning curve for C-Si and
is expected to continue for the
next 10 years till C-Si will reach
its saturation value: 1€/W
- thin films have the potential to
extend learning curve beyond CSi limit (less material and energy
in the process, simpler and highly
efficient process
PRICES OF MODULES AND SYSTEMS
IN SOME COUNTRIES
- Module prices: 3-4,5 €/W
40
35
- GCS: 5-7 €/W
30
25
- slight increase in prices
over the previous year
20
15
systems
10
5
2004
2003
2000
1999
1998
1997
1996
1995
1994
1993
IEA Source
1992
0
2002
modules
2001
Indicative prices (€/W)
45
- learning curve of systems:
shows a 15%-20% cost
decrease (BOS cost
decrease is along with
module cost reduction)
18
16
<1 kW S.A.
14
<10 kW G.C.
12
10
8
6
4
2
FR
A
G
B
R
IT
A
JP
N
M
EX
NL
D
NO
R
PR
T
SW
E
US
A
N
FI
DE
U
K
DN
E
CH
AU
AU
T
0
S
Installed systems prices ($/W)
SYSTEM PRICES
IEA Source
System prices depend on
- application (S.A or G.C.), size, location and mounting typology
- dedicated design, technical specification
PRICES IN ITALY
Modules
Year
2002
2003
2004
2005
€/W
3.5 – 4.3
3.1 – 3.9
2.9 – 3.7
3.2 - 4
Systems
Category
Off-grid (< 1 kWp)
Application
Lamps,
Rural electrification,
Industrial applications
On grid (< 10 kWp)
Rooftops
On-grid (>10 kWp)
Distributed generation
€/Wp
10 - 13
6–8
5.5 - 7
COST DISTRIBUTION
small G.C. plants
inverter (900 €/kW)
12%
engineering (700
€/kW)
9%
cables and
accessories (400
€/kW)
5%
supporting
structures (400
€/kW)
5%
manpower (1400
€/kW)
18%
PV modules (4000
€/kW)
51%
65% in large size
plants
COSTS IN S.A. SYSTEMS
• COSTS PROPORTIONAL TO THE SIZE OF THE PLANT
– PV modules
3,6 €/W
– Cables and accessories
0,4 €/W
– Supporting structures
35 €/m2
– Site preparation
10 €/m2
– dc/dc converter (charge controller)0,3 – 0,6 €/W
• COSTS PROPORTIONAL TO THE SIZE OF THE BATTERY
– Battery housing
80 €/kWh
– battery
200 €/kWh * N° of replacements
• COSTS PROPORTIONAL TO THE SIZE OF THE MAXIMUM LOAD
– inverter
400 - 700 €/kW
THE PV ENERGY COST
CkWh = (Ci*A + Cm) / E
• Ci: investment cost
– 6 - 7 €/W (grid-connected)
– 10 – 12 €/kW (stand alone)
• A: capital recovery factor = r / (1- (1+r)-T)
– r: interest rate (3 %)
– T: system life span (30 years)
• Cm: annual maintenance cost (50 – 200 €/kW)
• E: yearly energy production (1000 – 1300 kWh/kW)
•
CkWh:
– 0,3 – 0,35 €/kWh (grid-connected)
– 0,5 – 0,7 €/kWh) (stand alone)
kWh cost ($)
COST OF THE kWh
0,45
0,40
0,35
0,30
2010
0,25
0,20
0,15
0,10
0,05
0,00
1,00 2,00 3,00 4,00 5,00 6,00 7,00
PV plant cost ($/W)
For typical system prices (6 €/W)
corresponds 0,3 to 0,34 €/kWh,
depending on location (Solar
radiation)
Analysis show that system prices
may reduce to 3.5 €/W (0,17-0,2
€/kWh), comparable with the
price of energy paid by the end
user
COST OF THE kWh
Small G.C. systems (<5 kWp)
• Plant cost: 6 €/W
• maintenance : 1%
• interest rate: 4%
• optimal exposition
• kWh cost:
• 30 c€ in Sicily
• 40 c€ in North Italy
• 55 c€ in Germany
Energy cost
Electricity
cost($/kWh)
($/kWh)
For SAS the comparison is done with diesel generator or grid extension.
In the case of small daily loads PV is not only cleaner and more reliable,
but also a cheaper option
1,4
PV VS DIESEL AND GRID EXTENTION
0,6
1,2
PV 10 $/W
1
0,4
0,8
0,6
PV 5 $/W
0,4
PV 2 $/W
0,2
0,2
PV
PV/DIESEL
GRID
0
0,3
3
5
10
20
Daily load (kWh/day)
Daily load (kWh/day)
50
100
300
GENERATION COSTS
Cost of kWh (€)
1
0,8
900 h/a
0,6
0,4
1800 h/a
0,2
0
1990
Bulk cost
2000
2010
2020
2030
2040
years
In sunny countries, GCS will reach competitiveness with retail electricity in few years.
PV generation cost will began to compete with bulk production only within 20 years
PAY-BACK TIME
VANactualized
(€/kW)
(€/kW)
Net value
Time necessary to have NVA = 0
Net value (actualized): NVA = CFA – (Ci – Contribution on c.c.)
1.000
500
Payback time
-500
1
3
5
7
9
11
13
-1.000
-1.500
-2.000
-2.500
anni
years
Cashflow (actualized): CFA = S Pi * (1+r)-i
Proceed:
Pi = Ep*CkWh – Cm
(1+r)-i : actualization factor
r: interest rate
15
17
19
MIXED INCENTIVES
Pay back time (year)
25
20
15
Feed-in
tariff
Rooftop
programme
10
5
0
10
15
20
25
30
35
40
45
feed-in tariffs (c€/kWh)
50
55
60
plant size (kW)
cost of plant (€/kW) without 10%VAT
feed-in tariff + net metering or sale(c€/kWh)
3
30
300
6.500
6.000
5.500
44,5+15
46,0+8
49,0+8
35
20
10
2
2
2
1.100
12
1.100
13
1.100
11
maintenance cost (€/kW/y)
interest rate (%)
6.000
3 kW
4.000
30 kW
2.000
300 kW
years
-4.000
-6.000
-8.000
29
27
25
23
21
19
17
15
13
9
7
5
11
-2.000
3
0
1
(€/kW)
Net value actualized
VAN
energy produced (kWh/y/kW)
PAY BACK TIME (year)
ADDED VALUE
• Electric
– Grid parameters improvement (peak, transmission losses)
– Emergency
• Environmental
– Emission reduction, acid rain prevention
• Architectural
– Building functions (heat and noise insulation water and fire
protection electromagnetic reflection)
• Socio-economic
– Induced employment
– Resource diversification
– Technological transfer
COSTS AND ADDED VALUE
42
120
added value
incentivs
incentives
effective cost
60
14
0
40
20
conventional energy
apparente cost
80
apparent cost
28
kWh cost
kWh cost (c€/kWh)
100
0
-20
-14 -40
present
future
PV PROS AND CONS
• HIGH COST
At present is not realistic to recourse to this technology for
– Energy source diversification
– Significant emission reduction
• INTRINSIC FEATURES
– Among the RES is the most attractive and promising for local and
diffuse electricity production (medium and long term)
• HIGH STRATEGIC VALUE
– National Governments have launched important Programs
increasing
• Market
• Production capacity
• R&D efforts
INCENTIVES
Country
Initiatives
ITALY
Roof top programme almost completed (17 MW). Feed-in tariff
launched in September 2005 (from 50 to 60 c€/kWh). 80 MW/year
FRANCE
Public subsidy: 57% of installed cost. Budget: 18,9 M€
GERMANY
Feed-in law amended (50 c€/kWh + soft loans). Budget in 2004: 250
M€. Installed power 1400 MW
SPAIN
Feed-in tariffs ranging from 40 to 70 c€/kWh. Total capacity 150 MW
UK
Major Demonstration Programme. Budget 31 MGBP. Grants: 50%
JAPAN
Incentives on capital cost reduced to 5-10%. Budget 40 M€. Installed
power 1400 MW. Target 5 GW by 2010
USA
Subsidy and tax credit in California, Arizona, New Jersey, New York
and North Carolina for a total budget of 180 M$
CHINA
National Township Electrification Program: 660 villages (16 MW) + 10
000 (265 MW) by 2010
INDIA
Solar PV Demonstration and Utilisation Program: 325 000 SHS
installed with grant support
NATIONAL PROGRAMS
• STRATEGY AND MOTIVATION
– Market growth (allowing companies to plan their
investments)
– Technology diffusion
– PV industries reinforcement
– Definition of continuative R&D programs
– New job opportunities
• FINAL GOAL
– Economic competitiveness achievement
• Scale factor
• Development of most competitive components
NATIONAL PROGRAMS
Public budget
1400
MUSD
• Over a decade public
spending has
increased from year to
year
• Spending initially
focused on R&D
• Spent on market
stimulation increased
in 2001
• Market stimulation
started to decrease in
2004
1200
Market Stimulation
Demonstration
1000
R&D
800
600
400
200
0
IEA source
1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
ECONOMIC BENEFITS
Year 2004
12.000
Installer, distributer
10.000
Persons
-In the last years there has
been a significant growth in
employment (DEU, USA)
Manufacturer
8.000
- Persons employed in
R&D, industry and
installation reach in 2004
about 30 000 unit.
R&D
6.000
4.000
- most new jobs are on
installation and marketing
DNK
FIN
SWE
PRT
KOR
NOR
GBR
CHE
ITA
CAN
FRA
NLD
AUS
USA
IEA Source
DEU
0
JPN
2.000
- component production
tend to move towards low
cost base economy
ITALIAN PV PROGRAMME
• Strategic goals
–
–
–
–
PV cost decrease
Development of national competitive industries
Local development
New job opportunities
• Relevant results
–
–
–
–
–
38 MW of total cumulative PV power installed
National roof-top and feed-in Programmes
Big effort in RD&D
Competitive industrial system (production capacity 30 MW/y)
Growth of popular acceptance for PV
R&D ORGANIZATIONS IN ITALY
Organisation
ENEA (Casaccia, Portici)
R&D area
c-Si, a-Si, a-Si/c-Si
heterostructures
Institute for Certification (CESI) GaAs (space/terrestrial
applications)
University of Milan
c-Si
University of Ferrara
c-Si
University of Parma
Compound films
National Council for Scientific
Research (Bari)
a-Si
National Council for Scientific
Research (Bologna)
c-Si, a-Si/c-Si heterostructures
ENEA R&D ACTIVITIES
• Systems and components
– Small grid connected plants
•
•
•
•
Characterisation of BIPV modules and ageing tests
Development of innovative inverters
Inverter characterisation and pre-qualification
Grid interface device tests
– Hybrid systems
– Medium size plants
• Experimentation and long term performance analysis
ITALIAN ROOF-TOP PROGRAMME
• Started on March 2001
• Small grid connected BIPV plants
• Economic incentives: only on investment cost (up to 75%)
• Maximum investment cost allowed: 7 – 8 €/W
• Public funds: 115 M€
• Total investments: 175 M€ (23 MW expected)
• Starting phase (tune procedures and check people consensus)
– National Programme
• 21 Regional Programmes
DECREE 387/03
• Put into effect the EU Directive 77/2001/CE in the Italian
legislation and forecasts:
– an annual increase of 0,35% in “green sources” share
obligation, from current 2%;
– procedure simplification for plant installation and grid
connection;
– advertising campaigns;
– facilitations for small renewable source plants up to 20 kW
• Forecasts dedicated support measures for PV that include:
– fixed feed-in tariffs, decreasing over time, for different
installations and a purchase obligation by the utilities.
FEED-IN TARIFFS IN ITALY
Decree 28/7/05 and 6/2/06
Requirements of plants who can benefit of feed-in tariffs: 1 kW - 1 MW
Plant size (kW)
Tariffs (€/kWh)
Further value
1 <> 20
0,445
Net metering (15 c€/kWh)
20 <> 50
0,46
Self consumption or sale
(9,5 c€/kWh)
0,49 max.
Self consumption or sale
(9,5 – 7 c€/kWh)
50 <> 1000
FEED-IN TARIFF IN ITALY
– Duration of the support : 20 years
– Maximum Power to be supported: 500 MW
• 360 MW (< 50 kWp) + 140 MWp (> 50 kWp)
– Annual limit: 80 MW
– Final target at 2015: 1 GW
– Tariff reduction:5%/year
– Tariff increased of 10% for BIPV
– Resources for the allocation of feed-in tariffs are covered by
the revenue of the A3 component of the electric tariff (3
€/Year/user)
APPLICATIONS SUBMITTED IN 2005
• Admitted applications within September: 2.914 (79% of
submitted)
– 2.868 P<50 kW (60,6 MW)
– 46
P>50 kW (27 MW)
• Admitted applications within December: 6.207 (75% of
submitted)
– 6.137 P<50 kW (134,7 MW)
– 70
P>50 kW (43,7 MW)
• Cumulated power in 2005: 266 MW
• Most active regions: Apulia, Sicily, Campania.
SUPPORT INCENTIVES COMPARISON
CAPITAL COSTS
FEED-IN TARIFFS
End user
Citizen, public
organization (limited
capital)
Investors, builders,
commercial subjects
(cash flow availability)
Management
Public Bodies (Regions,
Ministry)
Electric Utilities
Economic
consideration
To overcome economic
barrier in s.a or g.c.
applications
To internalize
externalities of
traditional sources
Problems
Don’t encourage
investment for PV
Impact on the market
depends on tariff value
CONCLUSIONS
• Although impressive progress have already been made, the early
stage of PV development indicates a large margin of growth.
In the next 10-20 years is expected:
– Efficiency 10-25% (35%: concentrators), lifetime 40 years
– Electricity cost from PV: 5-15 c€/kWh
– Components based on abundant non toxic materials
– Implementation of new concepts (III generation)
– BIPV in all new building (net producer)
– Multi MW in deserts (hydrogen production)
– Cumulated power: 200-400 GW
– Jobs created: 300 000
– Electricity to 100 million families
CONCLUSIONS
• In order to achieve the expected aims is necessary:
– Define the strategies and the goals
– Develop policy initiatives
– Balance the efforts in R&D with the PV potential
– Accelerate the transfer from research to production
– Overcome the barriers (technical, standardization, financing,
market)
– Strength the cooperation among sectors (electronics, buildings,
nanotechnologies)
– Develop sustainable support measures (decreasing)
– Foster the connection among R&D, Industry and Policy