THE PHOTOVOLTAIC THE PHOTOVOLTAIC TECHNOLOGY TECHNOLOGY

Ing. S. Castellocastello@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

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 TECHNOLOGY

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 (1-10kW)

• 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

PV MODULES

DC LOADS

CHARGE CONTROLLER

BATTERY

REMOTE DWELLINGS

GENERATOR

CHARGE CONTROLLER

DC/ACINVERTER

PVGENERATOR

BATTERY

COMMERCIAL AC LOADS

DC LOADS

VILLAGE ELECTRIFICATION

GENERATOR

CHARGE CONTROLLER

DC/ACINVERTER

PVGENERATORE

BATTERY RECTIFIER

DIESEL

LOADS

WATER PUMPING

GENERATOR

PUMP(CENTRIFUGAL

OR RECIPROCATING)

DC/ACINVERTER

(FREQUENCY VARIABLE)

PVGENERATORE

CATTLE WATERING

TANK

SPRINK

TANK

GENERATOR

DC PUMP

PVGENERATORE

WATER

GRID CONNECTED SYSTEMS• Not competitive yet, but potentially able to make a substantial contribution

to sustainable electricity production in industrialized countries.

• Applications: – Diffuse generation 1 – 50 kW– Power stations > 1 MW– Grid support (weak feeder lines) 0,5 – 2 MW– Small grid support (islands) 100 – 500 kW

DC/ACINVERTER

PVGENERATORE

LOADS

GRID

GRID CONNECTED PLANTPV MODULES

DOUBLECOUNTER

COMMERCIAL AC LOADS

INVERTER

GR

ID

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 PLANTSIN 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

Delphos, 600 kWPower station

Lamezia, 600 kWPV-Wind

Vasto, 1000 kWPower station

Leonori, 86 kWCar parkig

Altanurra, 100 kWGrid-connected

Carloforte, 600 kWPV-Wind Mandatoriccio, 216 kW

Grid-connectedVulcano, 180 kW

Grid support

Serre, 3300 kWPower station

LOCATION OF SOME DEMO PLANTS

Casaccia, 100 kWCar parking

Zambelli, 70 kWWater pumping

Giglio, 450 kWCold store

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)

• 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

ANIT PROJECT

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

PROCESS PHASES

ENERGETIC OCCURRENCE

kWh/m2

Modules

m-si wafer production 175

Cells formation 400

Module assembly 45

BOSSupporting 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

ENERGY PAY BACK TIME

FUEL SAVING• Plant life time 30 years• Energy pay back time 5 years• Plant useful life 25 years• Yearly energy production 1 300 kWh/kW• Energy produced in 25 years 32 500 kWh/kW• 1 kg of fuel 4 kWhe• Fuel saving 8 000 kg/kW

• CO2/kWh 0.77 kg• Emissions avoided 25 000 kg/kW

Experience conducted by ENEA on 80 modules installed in 1980

Results:Declared efficiency 10,6% Measured efficiency - at acceptance tests: 9,54%, (-10%) - after 11 years: 9,14%. - after 25 years: 8,6%.

Efficiency degradation: 10% in 25 years Mean degradation rate: 0,4% /year

MODULE EFFICIENCY DEGRADATION

Tedlar detachment or delamination

module browning

Defects detected after 25 years don’t have caused further efficiency degradation with respect to the natural degradation (0,4%/year)

This experience demonstrate that the life time of “old generation”, “glass-tedlar” can be considered around 30 years.

MODULE FAILURES

Tedlar leak

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

0,000

0,200

0,400

0,600

0,800

1,000

Jan1992

Jan1993

Jan1994

Jan1995

Jan1996

Jan1997

Jan1998

Jan1999

Jan2000

Jan2001

PR

Inve

rter

fai

lure

Inve

rter

fai

lure

Efficiency degradation

strin

g fa

ilure

TIPICAL SEQUECE OF EVENTS

0

2

4

6

8

10

12

14

0 5 10 15 20 25 30 35

Years

pla

nt

effi

cien

cy (

%)

Inve

rter

sub

stit

utio

n

Module efficiency degradation (0,4%/a)

Module failure

(infiltration, ossidation,

delamination)

fail

ure

(PV

gen

or in

vert

er)

Syst

em tu

ning

IMPACT ON LAND• Land occupation

– Plant power 1 MW– Yearly energy production 1.300 MWh– Domestic users supplied 600 (in Italy) – Land required 1.5 hectares

• Energy consumption in Italy 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

Tilt=latitude

ONE AXIS TRACKING

north-south axis tracking flat plate

Fixed flat plate (tilt = latitude)

Incident energy > 20%- 25% with respect to fixed plated

TWO AXIS TRACKING

Tilt = latitudine

Sistema piano ad inseguimento su due assi

TWO AXIS TRACKING

2 axis tracking flat plate

Incident energy > 30%- 35% with respect to fixed plated

Fixed flat plate (tilt = latitude)

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

• The efficiency of cells is higher (30% - 40%)– high concentration factors: 100X – 1.000X (Irr*logIrr)– smaller cells

Solar radiation Solar radiation

PV cell

PV cell

Lens

• PV material (high cost), is partially substituted with mirrors or lenses (lower cost)

CONCENTRATING PVThe 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

Dishes

Central tower

Trough system

CONCENTRATORS

- 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

Heat sink

PV cells

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

inverter efficiency

82

84

86

88

90

92

94

Vulc1 Delp1 Casac Delp2 Vasto Serre Altan

effic

ienc

y (%

)

PV genearator efficiency

4

6

8

10

Vulc1 Delp1 Casac Delp2 Vasto Serre Altan

effic

ienc

y (%

)

0,6

0,7

0,8

0,9

mea

n ef

f. /

nom

inal

eff.

84 85 91 91 93 94 96

0

5

10

15

20

25

Vulc1 Delp1 Casac Delp2 Vasto Serre Altan

Spec

ific

cost

s (E

uro/

Wp)

plant

module

Costs

INDICES OF PERFORMANCE

0

1

2

3

4

5

1992 1993 1994 1995 1996 1997 1998 1999 2000

Yie

ld a

nd lo

sses

(h/d

)

Ls

Lc

Yf

0

0,2

0,4

0,6

0,8

1992 1993 1994 1995 1996 1997 1998 1999 2000

Per

form

ance

ra

tio

0

2040

6080

100

Ava

ilab

ility

(%)

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

0

500

1000

1500

2000

2500

3000

3500

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

MW

Grid-connected centralisedGrid-connected distributedOff-grid non-domesticOff-grid domestic

- IEA countries: 2.8 GW- Total: 3.3 GW

- 1.2 MW in 2004- Growth rate: 42%

- Projections for 2005: 4,5 GW

- applications: 70% of small grid connected systems

INSTALLED POWER

Worldwide

IEA countries

IEA source

CUMULATIVE POWER IN THE COUNTRIES(end 2004)

52 19 13 23

794

39 26,30 8,2 31

1132

10 18 496,9

365

0

200

400

600

800

1000

1200

AUS

AUT

CAN

CHE

DEU

ESP

FRA

GBR ITA

JPN

KOR

MEX

NLD

NOR

USA

MW

94% in JPN, USA and DEU

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

IEA source

TRENDS IN SOME COUNTRIES

Annual rate growth:

- DEU: 137%Sustained by feed-in tariffs (0.5 €/kWh)

- constant in JPN: 22%, net metering at 0.2 €/kWh + low subsidy on capital costs (10%)

0

50

100

150

200

250

300

350

400

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

inst

alle

d po

wer

(MW

)

JPN

DEU

USA

NLD

AUS

FRA

AUT

ITA

IEA source

DISTRIBUTION OF APPLICATIONAS

- PV roofs : CHE, DEU, GBR, JPN, NLD

- Vacation cottages: SWE NOR, FIN

-Rural electrification: MEX, FRA

- Commercial applications: USA e AUS

0%

20%

40%

60%

80%

100%

AU

S

AU

T

CA

N

CH

E

DN

K

DE

U

FIN

FRA

GB

R

ISR

ITA

JPN

KO

R

ME

X

NLD

NO

R

PR

T

SW

E

US

AInst

alle

d po

wer

by

appl

icat

ion

(%)

Grid-connected centralizedGrid-connected distributedOff-grid non-domesticOff-grid domestic

IEA source

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

0

5

10

15

20

25

30

35

40

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

inst

alle

d p

ow

er (

MW

)

on-grid distributed

on-grid centralised

off-grid domestic

off-grid industrial

Law 308: rural electrification

Rooftop Programme

DemonstartionProjects (UE)

INDUSTRIAL PRODUCTION

0

200

400

600

800

1000

1200

1400

1993 1994 1995 1995 1997 1998 1999 2000 2001 2002 2003 2004

Mo

du

le p

rod

uct

ion

(M

W)

Module production

Production capacity

IEA source

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)

0

100

200

300

400

500

600

700

Japan USA Europe Rest

mod

ule

prod

uctio

n (M

W)

Othera-Si

c-Si

IEA source

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

0

50

100

150

200

250

300

350

400

BP

So

lar

Q c

ell

SO

LO

N A

G,

Sh

ell S

ola

rS

ola

rwat

tS

ola

ra A

GA

lfas

ola

r F

lab

eg S

ola

rG

SS

Gm

bH

S.M

.D. S

ola

r-A

nT

ec S

ola

rIs

ofo

ton

BP

So

lar

Ate

rsa

Ph

oto

wat

tIC

PH

elio

sE

uro

sola

reS

har

pK

yoce

raM

SK

San

yoM

itsu

bis

hi

Kan

eka

Sh

ow

a S

hel

lS

hel

l So

lar

Sh

ell S

ola

rG

PV

Art

ic S

ola

rS

hel

l So

lar

BP

So

lar

Ast

roP

ow

erR

WE

Sch

ott

Un

ited

So

lar

AU DEU ESP F GB IT JPN NL P SW USA

Mo

du

le p

rod

uc

tio

n (

MW

/ye

ar)

MODULE MANUFACTURERS

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)

0%

20%

40%

60%

80%

100%

1998 1999 2000 2001 2002 2003 2004

other

a-Si

c-Si

p-S

i

- 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)

TECHNOLOGY PRODUCTION

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 EXPECTATIONSTUDY COMPARISON

0

200

400

600

800

1000

1200

1400

1600

1800

2000

2000 2002 2004 2006 2008 2010

year

mo

du

le p

rod

uc

tio

n (

MW

)

Bayer (15%)

Kyocera (18%)

Strategies Unlimited (23%)

+60%

+40%

Growth rate)

MODULE PRICES EVOLUTION

19

11,37

53,2 3,2 1,40

5

10

15

20

1970 1980 1990 2000 2010 2020year

(€/W)

- Modules prices 3.5 €/W- Module prices increased:

- tightening of Si supply- more order in the books of manufacturers than they could fill in

- 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

0,1

1

10

0,1 1 10 100 1000

Cumulated power (GW)

Price

s of m

odul

es (€

/W)

thin film

c-Si

2000

2010

2020

Growth rate in the past: 20%

- 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%)

- 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 C-Si limit (less material and energy in the process, simpler and highly efficient process

PRICES OF MODULES AND SYSTEMS IN SOME COUNTRIES

0

5

10

15

20

25

30

35

40

45

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

Indi

cativ

e pr

ices

(€/W

)

systems

modules

- Module prices: 3-4,5 €/W

- GCS: 5-7 €/W

- slight increase in prices over the previous year - learning curve of systems: shows a 15%-20% cost decrease (BOS cost decrease is along with module cost reduction)IEA Source

SYSTEM PRICES

0

2

4

6

8

10

12

14

16

18

AUSAUT

CHEDNK

DEUFIN

FRAGBR

ITA

JPN

MEX

NLDNO

RPRT

SWE

USA

Inst

alle

d s

yste

ms

pri

ces

($/W

)

<1 kW S.A.

<10 kW G.C.

System prices depend on- application (S.A or G.C.), size, location and mounting typology- dedicated design, technical specification

IEA Source

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 Application €/Wp

Off-grid (< 1 kWp) Lamps, Rural electrification,Industrial applications

10 - 13

On grid (< 10 kWp) Rooftops 6 – 8

On-grid (>10 kWp) Distributed generation 5.5 - 7

COST DISTRIBUTIONsmall G.C. plants

PV modules (4000 €/kW)51%

manpower (1400 €/kW)18%

supporting structures (400

€/kW)5%

cables and accessories (400

€/kW)5%

engineering (700 €/kW)

9%

inverter (900 €/kW)12%

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)

COST OF THE kWh

0,000,050,100,150,200,250,300,350,400,45

1,00 2,00 3,00 4,00 5,00 6,00 7,00

PV plant cost ($/W)

kWh

co

st (

$) 2010Rome

Palermo

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

0

0,2

0,4

0,6

0,8

1

1,2

1,4

0,3 3 5 10 20 50 100 300

Daily load (kWh/day)

Elec

trici

ty c

ost (

$/kW

h)

PV 10 $/W

PV 2 $/W

PV 5 $/W

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

Diesel 0.75 $/LDiesel 0.5 $/L

Grid ext 1 km

Grid ext 5 km

Grid ext 20 km

0,6

0,4

0,2

En

erg

y c

ost

($

/kW

h)

Daily load (kWh/day)

GRIDPV PV/DIESEL

PV VS DIESEL AND GRID EXTENTION

0

0,2

0,4

0,6

0,8

1

1990 2000 2010 2020 2030 2040

years

Co

st o

f kW

h (

€)

Price payd by end user (including taxes)

Bulk cost

900 h/a

1800 h/a

Grid connected rooftop

systems

GENERATION COSTS

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 TIMETime necessary to have NVA = 0Net value (actualized): NVA = CFA – (Ci – Contribution on c.c.)

Cashflow (actualized): CFA = Pi * (1+r)-i

Proceed: Pi = Ep*CkWh – Cm (1+r)-i : actualization factorr: interest rate

-2.500

-2.000

-1.500

-1.000

-500

-

500

1.000

1 3 5 7 9 11 13 15 17 19

anni

VA

N (

€/k

W) Payback time

yearsNet

val

ue a

ctua

lized

(€/

kW)

0

5

10

15

20

25

10 15 20 25 30 35 40 45 50 55 60

feed-in tariffs (c€/kWh)

Pa

y b

ack

tim

e (

yea

r)

c.c.=75% c.c.= 60%

c.c.= 0%

c.c.= 20%

Feed-in tariff

Rooftop programme

MIXED INCENTIVES

-8.000

-6.000

-4.000

-2.000

0

2.000

4.000

6.000

1 3 5 7 9 11

13

15

17

19 21

23

25

27

29

years

VA

N

3 kW

30 kW

300 kW

plant size (kW) 3 30 300

cost of plant (€/kW) without 10%VAT 6.500 6.000 5.500

feed-in tariff + net metering or sale(c€/kWh) 44,5+15 46,0+8 49,0+8

maintenance cost (€/kW/y) 35 20 10

interest rate (%) 2 2 2

energy produced (kWh/y/kW) 1.100 1.100 1.100

PAY BACK TIME (year) 12 13 11

Net

val

ue a

ctua

lized

(€/

kW)

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

-40

-20

0

20

40

60

80

100

120

kWh

co

st

added value

incentivs

effective cost

present future

conventional energy

appa

rent

cos

t

appa

rent

e co

st

incentives

42

28

14

0

-14

kWh

cost

(c€

/kW

h)

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

INCENTIVESCountry 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

0

200

400

600

800

1000

1200

1400

1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004

MU

SD

Market Stimulation

Demonstration

R & D

Public budget• 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

IEA source

ECONOMIC BENEFITS

0

2.000

4.000

6.000

8.000

10.000

12.000

JPN

DEU

USA

AU

S

NLD

FRA

CA

N

ITA

CH

E

GB

R

NO

R

KO

R

PRT

SWE

FIN

DN

K

Per

sons

Installer, distributer

Manufacturer

R&D

-In the last years there has been a significant growth in employment (DEU, USA)

- Persons employed in R&D, industry and installation reach in 2004 about 30 000 unit.

- most new jobs are on installation and marketing

- component production tend to move towards low cost base economy

Year 2004

IEA Source

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 R&D areaENEA (Casaccia, Portici) 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 ITALYDecree 28/7/05 and 6/2/06

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)

50 <> 1000 0,49 max. Self consumption or sale(9,5 – 7 c€/kWh)

Requirements of plants who can benefit of feed-in tariffs: 1 kW - 1 MW

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