Bulk Solar Electricity Generation

June 08

Fernando Nuño

European Copper Institute

[email protected]

Bulk Solar Power Generation :CSP and CPV technologies

www.leonardo-energy.org

Index

Solar energy : why should it make sense? Definitions CSP review

– Technology– Project Development Issues– Generation costs – Market perspectives – Support

schemes

CPV review– Technology– Generation costs – Market perspectives

Ratios and comparisons


Solar resource available : much more than we need

The Earth receives from solar radiation in 10 days as much energy as the known fossil reserves

The Earth receives from solar radiation in 10 days as much energy as the known fossil reserves


Solar roadmap – Increasing role in the coming years


Where does concentration technology make sense?

Annual Direct Normal IrradiationAnnual Direct Normal Irradiation

Source : NASA


Where does concentration technology make sense?

Source : Schott Solar


The potential of Mediterranean basin

North Africa has an enormous potential. Interconnections with Europe could be then developed

Sources : Eurelectric 2007

German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety


Why solar energy fits well in hot climates

Spanish average load profile vs average irradiationSpanish average load profile vs average irradiation

Sou

rce

: R

ed E

léct

rica

de E

spañ

a


Index



schemes




Solar technologies and market share


Utility scale technologies

CSPCSP

CPVCPV

CONCENTRATION SOLAR POWER : thermal process– Heating a fluid– Generating mechanical power through a thermodynamic cycle (rankine, brayton, stirling…)– Converting mechanical power into electrical power (alternator)

CONCENTRATION PHOTOVOLTAICS : photovoltaic process– Concentrate solar radiation on the PV cell– Direct generation of electrical power

Solar Field

Power Block

Solar Field

Power Block


Index



schemes




CSP Technology overview

Parabolic TroughsParabolic Troughs

Parabolic Dishes with Stirling Engine

Parabolic Dishes with Stirling Engine

Central TowerCentral Tower

Fresnel ConcentratorsFresnel Concentrators


CSP Technology review Parabolic TroughsParabolic Troughs

Structure Parabolic Mirror

Receiver


CSP Technology review Parabolic TroughsParabolic Troughs

Solar Field

Power Block


CSP Technology review

Melted Salts

Hot Storage

Sol

ar F

ield

Melted Salts

Cold Storage

Steam Generator

Steam Turbine

Superheated Steam (100 bar, 380ºC)

Reheated Steam (17 bar, 371ºC)

Condenser

Pre-heater

Re-heater

Oil Expansion Tank

Deaerator

Oil 395ºC

Oil 295ºC

HFT (Heat Transfer Fluid)Technology in commercial operation

HFT (Heat Transfer Fluid)Technology in commercial operation



CSP – Technology review

Steam is generated directly in the collecting solar field, so no need for heat exchange, reducing costs and increasing efficiency


DSG (Direct Steam Generation)Coming soon…

DSG (Direct Steam Generation)Coming soon…


CSP : Project Development – Site issues

Meteorological compliance

Meteorological compliance

DNI > 1800 kWh/m2/year Measurement campaign required

Access to electricity and

gas grid

Access to electricity and

gas grid

Access to waterAccess to water

Flat land available

Flat land available

No special interest zone (urban, industrial, environmental protection)

Absolutely flat for parabolic troughs

Local authoritiesLocal authorities Should accept and support the project

In sunny places there is strong competition for water use!

Impact of cost of building a dedicated electrical line to reach the main grid Gas : required to maintain temperatures during the night (other fuels can

be considered for isolated zones)


CSP : Project Development – Site issues

Typical configurationsTypical configurationsSolar Field

Power Block


CSP : Project Development – Administrative issues

Request for Administrative Authorisation

Request for Administrative Authorisation

Environmental impact analysis

Environmental impact analysis

Public Information

Public Information

Obtaining Administrative Authorisation

Obtaining Administrative Authorisation

Consultation to affected entities

Consultation to affected entities

Responses to this publication

Reply to responses

Request for Project Approval

Request for Project Approval

Construction permits

Construction permits

Maturing period : 18 months


CSP : Project Development – Engineering, Procurement & Construction

Preliminary Basic

Engineering

Preliminary Basic

Engineering

Basic Equipment Purchase

Basic Equipment Purchase

Construction contracts

Construction contracts

In-Depth Engineering

In-Depth Engineering

Supply of equipment - Construction

Supply of equipment - Construction

Commissioning and test period

Commissioning and test period

Execution period : 24 months

Maturing + Execution period : 36 - 44 months


CSP : Project Development – Grid Access

Guarantee:20 €/kW

Guarantee:20 €/kW

Request to recognition of dispatchability

RE – PO 08/2007(see next slide)

Request to recognition of dispatchability

RE – PO 08/2007(see next slide)

Request for Access to the grid

Request for Access to the grid

TSO provides the conditions for grid

access

TSO provides the conditions for grid

access

Spanish SystemSpanish System

Project Developer presents its project

Project Developer presents its project

Project Developer asks for

connection point

Project Developer asks for

connection point

TSO provides connection point

TSO provides connection point


CSP : Project Development – Grid Access

Dispatchability RE – PO 08/2007Dispatchability RE – PO 08/2007 Spanish SystemSpanish System

Installation controlled from the dedicated TSO dispatching center

Program reliability:90% at 24 h horizon95% at 6h horizon

Required conditionsRequired conditions

Storage ability: 4h Energy restitution

efficiency : 60%

Voltage dip ride-through ability (voltage dip up to 1 second)

BenefitsBenefits

Less requirements and more guarantees to obtain access to the grid

Participation in ancillary services markets

Project Developper can make the choice to go for storage or not, so making its installation dispatchable or not.

If not dispatchable, grid access seems more difficult to obtain and would be subject to curtailments when in operation

Project Developper can make the choice to go for storage or not, so making its installation dispatchable or not.

If not dispatchable, grid access seems more difficult to obtain and would be subject to curtailments when in operation


CSP : Project Development – Technological issues

MirrorsMirrors Some companies developing solar projects are developing

its own technology, or buying mirror manufacturers

Absorber TubeAbsorber Tube

Support Structure

Support Structure

Thermal storageThermal storage

Manufacturers oligopoly Extremely critical and technical product (lasting vacuum, layers stability, high

transmissivity of glass, high absorptivity and low emissivity of absorber, junctions metal/glass, dilatation management…)

Several structures available in the market Continuous evolution to comply with alignment requirements at

the lowest cost

Liquid salts is the technology used for the moment, but many other are in development


CSP - Project Development – Storage optimisation


CSP - Project Development – Contractual structure and Project Finance

CONTRACTSCONTRACTS

Engineering Procurement & Construction (EPC)

Engineering Procurement & Construction (EPC)

Turn Key ContractTurn Key Contract

Separated Packages negotiated by Project

Developer

Separated Packages negotiated by Project

Developer

Operation & MaintenanceOperation & Maintenance

Grid ConnectionGrid Connection

Fuel ProcurementFuel Procurement



Turn Key ContractTurn Key Contract

One Main Contractor assumes the whole project and outsource the various packages to other companies

Price is negotiated ex-ante and is firm

Deadline is negotiated ex-ante and is firm (penalty otherwise)

Responsibility : only one visible head

One Main Contractor assumes the whole project and outsource the various packages to other companies

Responsibility : only one visible head

The Main Contractor assumes the work of supervision and coordination

20% more expensive than the option “separated packages negotiated by project developer”

To be financed by banks, it is the only contract structure acceptable

Financing Entity will obtain from Main Contractor the required guarantees



Contractual StructureContractual Structure

Project Developer

Financial Entity

Legal Advisor

Technical Advisor

Insurance Advisor

Environmental Advisor

Turn Key Main Contractor

Solar Field

Thermal Storage

Power Block

Civil Work Electrical Systems

PROJECTFuel

O&M Insurance

Electricity Sales



Main risks associated to CSP seen by Financial Entities

Main risks associated to CSP seen by Financial Entities

Melted Salts Storage Expected generation : – Availability and Quality of

solar radiation data– Thermal storage– Hybridizing with NG or

biomass

Availability of main components (mirrors, absorber tubes)

Experience of Main Contractor

Regulatory risk: once reached the targets set by the Ministry, no more support is available


CSP - Some ratios

50 MW - Without storage

50 MW - Without storage

Investment : 3000 €/kW

50 MW - With storage

50 MW - With storage

Annual production : 2050 hours for South Spain

Water consumption : 6m3/MWh

Gas consumption : 60 GWh /year

Collecting surface : 287000 m2, 52 linear km

Investment : 4500 €/kW up to 6000 €/kW

Annual production : 3000 to 4000 hours – South Spain

Collecting surface : increased according to the storage capability

Water consumption : 6m3/MWh - 1600 m3/day

Gas consumption : > 60 GWh / year


CSP - Support Schemes

SpainSpain CSP :

– Target : 500 MW in 2010– Tariff : 278 €/MWh or market price + 262 €/MWh lasting : 25 years

• After 25 years : 222 €/MWh or market price + 210 €/MWh

CPV : integrated to general PV– Target of 371 MW reached in 2007 (waiting for provisions for the period up to 2010)– Tariff : up to 2007 431 €/MWh – expected 300 €/MWh from September 2008. Lasting : 25 years + reduced tariff after that period– Expectations to discriminate CPV from general PV

Feed-in tariffs have provided the required confidence to carry out huge investments up to 6000 €/kW



North AfricaNorth Africa

Call to bid from national electricity agencies

ISCC : Integrated Solar Combined Cycle– Excellent way to recover solar energy and optimize its thermodynamic efficiency thanks to

higher temperatures reached by burning natural gas– ISCC by Abengoa Solar : Morocco 470 MW, Algeria 150 MW



USAUSA

State requirements RPS (Renewable Portfolio Standards) + remuneration based on PPA negotiation (Power Purchase Agreements) + pluri-annual Federal ITC application (Investment Tax Credit)

April 2008 : Pacific Gas & Electric Company (PG&E) subscribes a firm contract to buy electricity generated by solar plants in Mojave Desert : 500 MW + 400 MW optional

February 2008 : Arizona Public Service (APS) signs a contract with Abengoa Solar to buy electricity from a 280 MW solar power plant … SEGS series from 80’s : more than 300 MW with more than 20 years experience on parabolic trough technology


CSP – Current growth

Only in Spain, there will be confirmed firmly more than 1000 MW during 2008


CSP – Market expectations

According to German Aerospace Center (DLR), CSP has a growth potential of 40 GW by 2030


CSP – Market expectations

Much more optimistic, ESTELA, the European Solar Thermal Electricity Association, sees room for 60 GW by 2030 only in Europe…


CSP – Cost expectations

According to ESTELA, the European Solar Thermal Electricity Association, only a moderate reduction in the levelized cost of energy can be expected due to high increase of raw materials such as steel and concrete


Index



schemes




CPV - General features

In spite of its childhood (much less mature than CSP), already several MW installed around the world

The big cost reduction is still to come thanks to mass production

Doesn’t need cooling water (except some special applications)

Modular and scalable technology


CPV – The strategy

Substitution of the expensive semiconductor material with a cheap optical system and low-cost mechanics

Use of best efficiency cells


CPV - Advantages

No water needsNo water needs

Time to OperationTime to OperationLess sensitive to hot climatesLess sensitive to hot climates

Modular / ScalableModular / Scalable


CPV - Disadvantages

Sensitivity to cloudsSensitivity to clouds

No easy storage abilityNo easy storage ability

These two issues together should be solved, as TSO cannot accept sharp fluctuations in the generated power


CPV – Components: Cells - Triple junction cells

The principle is that each material operates at different wavelengths, the three covering a large spectrum


CPV – Components: Cells - Technology evolution

In 2009 an average production efficiency higher than 40% will be the rule for multijunction cells


CPV – Components: Concentrator - Technologies

LensLens MirrorMirror

Low Concentration

Cassegrain


CPV – Components: Concentrator - Technologies

Central tower CPVCentral tower CPV

Developed by Solar Systems in Australia


CPV – Components: Tracking system

Light need to be focused at the cell, not close to the cell The higher concentration ratio, the lower angle tolerance In practice, 0.1% accuracy is currently reached Solid structures are required New structural concepts are being developed

Need for increased accuracy

Need for increased accuracy


CPV – Potential for cost reduction

Flat PV : module reaches 45% of cost

share

Flat PV : module reaches 45% of cost

share

40% of remaining costs are proportional to area

40% of remaining costs are proportional to area

Reductions in module cost and required area would lead to drastic decrease of Levelized Cost of Energy

Source : Concentrix


CPV – Area reduction

For the same surface, almost 50% more installed power

For the same surface, almost 50% more installed power

To reach the same power, 30% less need

for materials

To reach the same power, 30% less need

for materials


CPV – Cost reduction expectations

Investment costs to be cut by 3 in 10 years

Investment costs to be cut by 3 in 10 years

Source : Concentrix


CPV – Cost reduction targets


CPV – Market growth – some examples

EMCOREEMCORE



GUASCOR FOTONGUASCOR FOTON



SOL 3GSOL 3G


Index



schemes




Comparative CSP - CPV

Parabolic troughs

Central tower

Stirling parabolic dish

CPV

Power Range 20 – 300 MW 20 – 100 MW 5 – 40 kW per dish. Scalable

10 kW – 20 kW per tracker. Scalable

Operating Temperature

395ºC 600ºC 700ºC PV effect, no thermal

System Efficiency (electricity / solar)

21% 23% 31% Current : 25 %Soon : > 30 %

Commercially available

Yes Soon Only prototypes

Yes, with huge amounts of MW available in coming years

Integrated Storage Thermal : Possible

Thermal : Possible

? No

Hybrid design Possible (any fuel)

Possible (any fuel)

Possible (any fuel)

No

Water consumption 6 m3/MWh Similar to parabolic trough

No water No water

Land use (Ha / MW) 2,5 – 3 (more if storage)

2 – 2,5 (more if storage)

2 2


Comparative CSP - CPV

Parabolic troughs

Central tower

Stirling parabolic dish

CPV

Current investment cost

4 – 6 €/W (according to storage size)

4 – 6,5 €/W 14 €/W 6 – 7 €/W

Current LCOE (Levelized Cost of Energy)

260 €/MWh in South Europe – 180 €/MWh in MENA

? ? 300 €/MW in Souht Europe. Lower in sunnier locations

Expected LCOE by 2020

200 €/MWh in South Europe. Lower in sunnier locations

In line with parabolic troughs

In line with parabolic troughs

120 – 150 €/MWh in South Europe. Lower in sunnier locations


References

• CSP summit – Madrid February 2008 – Intereconomía Conferencias• CPV summit, Madrid 1-2 April 2008 (http://www.cpvtoday.com/index.shtml)

• http://www.schott.com/csp/english/download/schott_memorandum_e.pdf• http://www.wbgu.de/wbgu_publications_annual.html

• http://www.eupvplatform.org/• http://www.csptoday.com/


Thank you!