Concentrated Solar Power Technologies: Current status · PDF fileInternational Workshop on: DESIGN OF SUBSYSTEMS FOR CONCENTRATED SOLAR POWER TECHNOLOGIES 19-22 December 2013. Jodhpur

International Workshop on:

DESIGN OF SUBSYSTEMS FOR CONCENTRATED SOLAR POWER TECHNOLOGIES19-22 December 2013. Jodhpur (India)

Concentrated Solar Power Technologies:

Current status and R&D Opportunities

Eduardo Zarza Moya

CIEMAT-Plataforma Solar de Almería

E-mail: [email protected]

International Workshop: “Design of Subsystems for CSTP Technologies”19-22 December 2013, Jodhpur (India)

Contents

1. Current status of CSTP Technologies

2. A major issue: Cost Reduction

3. Important R+D topics

4. Final remarks

Concentrating Solar Thermal Power Technologies


Contents




4. Final remarks



State-of-the-art of CSTP Plants

What is a Concentrating Solar Thermal Power (CSTP) plant ?

There are four different technologies:

Technologies available for CSTP plants:

Central receiver technology

A STP plant is a system where direct solar radiation is concentrated and then converted into thermal energy at medium/high temperature (300ºC – 800ºC). This thermal energy is then converted into electricity by a thermodynamic cycle.


100 m

Heliostat field

Receiver

Power Conversion

System

Tower

Central Receiver Plants


State-of-the-Art

• Depending on the fluid delivered by the receiver there are three different

technologies: a)saturated steam, b) superheated steam, and c) molten salts

View of the tower

Aerial view of PS-10 and PS-20 plants (saturated steam)


Liquid water

Saturated steam (40 bar)

Condenser

GeneratorTurbine

Steam storage

system

Receiver Saturated-steam plant


State-of-the-Art




The IVANPAH Project (377 Mwe, 150bar/555ºC steam)IVANPAH Unit 1 in operation (125 MWe)


State-of-the-Art




Molten-salt plant

Aerial view of the 19 MWe plant GEMASOLAR (Spain)


State-of-the-Art




• The technology of central receiver using air is under development, with small

experimental plants already available

Scheme of a central receiver plant using atmospheric airScheme of a central receiver plant using compressed air



Parabolic trough collectors







Parabolic Trough Collector

Receiver Tube

Parabolic trough concentratorStructure

A typical parabolic trough collector


Solar field

Power Conversion System

Solar Power Plant with Parabolic Trough Collectors



State-of-the-Art

Scheme of a typical HTF plant with parabolic trough collectors

• The technology fully proven is the HTF (Heat Transfer Fluid) technology, with or

without molten-salt storage systems


295 ºC Oil

395 ºC Oil

Steamgenerator

Deaerator

Reheater

Oil expansion vessel

Steam turbine

CondenserG

So

lar

Fie

ld

Preheater

Superheated Steam (104bar/380ºC)

Reheated steam 17bar/371ºC

G(hot tank)

(385ºC)

Molten salts

(Hot tank)

Molten salts

(Cold tank)

(285ºC)


• Three plants have been put into operation in Morocco, Argelia and Egypt with a HTF

solar field integrated into a CC plant. This is an hybrid concept called ISCCS plant

(integrated solar combined cycle solar plant)

State-of-the-Art• The technology fully proven is the HTF (Heat Transfer Fluid) technology, with or

without molten-salt storage systems






Stirling dishes






ConcentratorReceiver

Estructure

Stirling Dish

Stirling engine


State-of-the-Art

• Several designs have been developed (the 3-kWe and 25-kWe American

designs and the 10 kWe European design). However, no commercial plan

is in operation

Stirling Dish

The 10kWe Envirodish designThe 25kWe design by SESDisco Stirling de 3 kWe (EEUU)





Stirling dishes



Compact Linear Fresnel reflectors




Receiver pipe

Rectangular reflectors

Compact Linear Fresnel Reflector (CLFR)


State-of-the-Art

• Two different designs promoted by AREVA and ABB-Novatec are competing

at commercial scale. The main difference is the receiver tube design.

CLFR design promoted by AREVA CLFR promoted by ABB-Novatec

Compact Linear Fresnel Reflector (CLFR)


Contents




4. Final remarks



A significant commercial deployment of the CSTP plants is takingplace, specially in Spain.

A Major Issue of CSTP Plants: Cost Reduction

2

In operation:

(September, 2013

46 plants / 2103,8 MW

Under construction:3 plants/ 200 MW

- 41 PT PTC

(2022,5 MWe)

- 3 CR

(49,9 MWe)

- 2 CLFR

(31,4 MWe)




(Information given by CSP Today)


Current CSTP plants are profitable because of the publicsubsidies (feed-in tariff, tax credits, ..)

A significant reduction of public incentives can be expectedduring next years

CONCLUSION

A significant R+D effort is required to improve the technology ofCSTP plants and make it more cost effective, because this will be theonly way to keep a significant commercial deployment and thus becomea key pillar of a more sustainable energy market.

Most of the current CSTP plants are using very conservativedesigns with a little degree of innovation




Source: ESTELA / ATKearney, June 2010

Expected cost reduction

Cost reduction achieved

by PV and wind

PV: 70% cost reduction, dromv5$/W (1998) to 1.4$/W (2010)

Wind: 60% cost reduction, from 4.3$/W (1984) to 1.4$/W (2010)

All the technology assessments performed so far have shown that there is a

great potential for cost reduction:



Contents




4. Final remarks



Relevant Topics for R+D in CSTP Plants

Suitable R+D+i programs have to be defined and developed to tackle the technical challenges associated to these requirements and to continue the commercial deployment of CSP plants.

LCOE reduction (lower costs and or higher efficiency)

CSTP plants must become more competitive with conventional power

plants and more feasible for arid zones with lack of water. Three of

the main requirements to achieve these objectives are:

Better dispatchability

Better environmental sustainability


Technical Challenges for LCOE reduction

Production process and technology improvement for key components

Topics and associated items that would bring costs down are:

• New heliostat, parabolic trough and parabolic dish designs specially conceived

to reduce the amount of manpower for both manufacture and on-site assembly

Diseño EuroTrough (Europa) Diseño SenerTrough (España) Diseño AlbiasaTrough (España) Diseño SkyFuel (EEUU)


1 m2 Heliostat developed by E-Solar (EEUU)14,3 m2 Heliostats developed by BrightSource (Israel)







O&M cost reduction• New working fluids (e.g.,water/steam, compressed CO2 or N2, .) allowing higher

temperatures in parabolic trough collectors

The PSA DISS test facility

B.O.P. buildingRow of collectors







The PSA test facility using compressed CO2 and N2 as working fluids

• New working fluids (e.g., water/steam, compressed CO2 or N2, .) allowing higher






O&M cost reduction



• Development of more durable components (reflectors, receiver pipes, ball-joints, ..)

with lower maintenance costs

• Development of innovative Stirling engines with better reliability and lower

maintenance costs





O&M cost reduction• New working fluids (e.g., water/steam, compressed CO2 or N2, .) allowing higher




• Development of improved volumetric receivers with porous metallic matrix to use

atmospheric air as working fluid

• New working fluids (e.g., water/steam, compressed CO2 or N2, ..) allowing higher


• New materials for higher solar radiation fluxes (1 MW/m2) that would achieve

higher thermodynamic efficiencies, mainly in central receiver plants

• Development of turbo-machinery specially designed for CSTP plants, in a wide

power range

Items that would increase the efficiency of CSTP Plants are:



Increase the number of hours of operation

• Development of cost-effective thermal storage systems for both sensible and

latent heat storage

Topics and associated items that would improve dispatchability are:

400 kWh-prototype of thermal storage system using concrete

Tube bundle

1,7 m

1,3 m

Technical Challenges for Better Dispatchability


200 kWh PCM prototype testeed at PSA(Project DISTOR)

700 kWh PCM prototypetested in Spain in 2011(Project REALDISS)




latent heat storage



• Development of thermo-chemical storage concepts




latent heat storage


H = 100 kJ/mol , Teq. =507ºC


Better predictability for the electricity production

• Development of good plant simulation models

• Development of accurate weather forecasting and nowcasting tools


• Development of thermo-chemical storage concepts



latent heat storage



Development of systems with lower water needs

Sites with high solar radiation usually have a shortage of water resources, thus

demanding CSTP plants with a low water consumption. Additionally, thermal oils

currently used in parabolic trough plants can have a significant environmental impact

in case of fire or leaks

• Dual cooling systems (wet for Summer time and dry for Winter time)

• Dry-cooling systems with higher efficiency

Technical Challenges for Lower Environmental Footprint



Cooling water tower

Air-cooled condenser

TURBINE

Tube-bundle condenser

Condensate

steam

Scheme of a dual cooling system (Dry for Winter and Wet for Summer)


Development of systems with lower water needs

Sites with high solar radiation usually have a shortage of water resources, thus

demanding CSTP plants with a low water consumption. Additionally, thermal oils

currently used in parabolic trough plants can have a significant environmental impact

in case of fire or leaks

• Dual cooling systems (wet for Summer time and dry for Winter time)

• Dry-cooling systems using the advantage of a “negative thermal storage” using

lower ambient temperatures at night time

• Dry-cooling systems with higher efficiency

New working fluids for parabolic troughs with lower environmental impact than

thermal oil



Contents




4. Final remarks



Final Remarks

CSTP Plants are a feasible option to achieve a more sustainable

energy market

Although the current cost of solar thermal electricity is still high,

there is a great potential for cost reduction and thus become more

competitive

A significant R+D effort is required to accomplish the expected cost

reduction

There are already outstanding R+D infrastructures available

Current technical challenges involve many different industrial

sectors (chemical, metallurgy, electronics, …).


The largest R+D centre in the World for Solar Thermal Concentration:

Plataforma Solar de Almería (PSA)

1. Central Receiver Plants

3. Parabolic troughs with DSG

7. Stirling dishes

2. Parabolic troughs with thermal oil

1

1

2

4

3

5. Compact Linear Fresnel Concentrator

56

6. Thermal storage with molten salts

4. Parabolic troughs with pressurized CO2

7

Spanish R+D Infrastructures for CSTP Plants

International Workshop on:

DESIGN OF SUBSYSTEMS FOR CONCENTRATED SOLAR POWER TECHNOLOGIES19-22 December 2013. Jodhpur (India)

Concentrated Solar Thermal Power (CSTP) Technologies:

Current Status, Technology Gaps and R&D Opportunities

Eduardo Zarza Moya

CIEMAT-Plataforma Solar de Almería

E-mail: [email protected]

End of the Presentation

Thank you very much for your attention !!

Development of new thermal storage systems (reliable, cheap and efficient)

Stirling engines with better reliability and lower maintenance costs

Higher-priority technical challenges

New working fluids for parabolic trough collectors (with higher operating

temperatures and environmentally friendly)

New receivers for parabolic trough and tower plants (cheaper and durable)

New cooling systems with lower water consumption

Documents

Concentrated Solar Power Technologies: Current status · PDF fileInternational Workshop on: DESIGN OF SUBSYSTEMS FOR CONCENTRATED SOLAR POWER TECHNOLOGIES 19-22 December 2013. Jodhpur