Concentrated Solar Power Course - Session 1 : Fundamentals

transcript

By Manuel A. Silva Pérezsilva@esi.us.es

March 3, 2010

Concentrated Solar Thermal PowerTechnnology Training

Session 1

http://www.leonardo-energy.org/csp-training-course-5-lessons

Session 1

• Introduction to Leonardo ENERGY• Fundamentals of Thermal Concentrating Systems• Solar Thermal Power Plants

Leonardo ENERGY:Education, Training and Advocacy on Sustainable Energy

170 partners from industry and academia contribute to Leonardo ENERGY

Leonardo ENERGY’s coordination is done by a team of professionals from the European Copper Institute and its European network of 11 offices

5,000 visitors/day, 69,000 e-mail subscribers, weekly webinars, monthly courses

What can you expect from us?

Global Solar Thermal Energy Council REEGLE

Estela Solar

Protermosolar

Seville University

Today’s webinar partners

CSP Today

SOLAR THERMAL POWER

Manuel A. Silva Pérez

silva@esi.us.es

Fundamentals of solar thermal concentrating systems

Solar Thermal Concentrating Systems

Systems that make use of solar energy by first concentrating solar radiation and then converting it to thermal energy

• Uses:– Electricity (Solar Thermal Power)– Industrial Process Heat– Absorption cooling– Chemical processes– …

Solar energy

• Abundant• High-quality energy

• Variable (on time)• Unevenly distributed (on space)• Low density

Excelent Very good Good Inappropriate

Solar resource availability. The solar belt

3000 km

90 % of the total electricity demand could be supplied from STP plants covering 300x300 km2.

Effcient transmission via HVDC would allow electricity supply to remote areas with moderate losses.

DESERTEC project: STP plants in the Magreb Area to supply electricity for Europe and Africa

Solar resource availability. The Desertec project

Why high temperature?

Beam Irradiance

Radiative losses (emitted by receiver)

Difuse Irradiance

The sun as a heat source

Why concentrate solar radiation?

Beam Irradiance

Radiative losses (emitted by receiver)

Difuse Irradiance

Ideal concentrating system

• The receiver (or absorber) converts concentrated solar radiation to thermal energy (heat)

• An ideal receiver may be characterized as a blackbody, which has only radiative losses

CONCENTRADORCONCENTRATOR

RECEIVER

ThermalEngine

Beam Irradiance

Receiver losses

Concentrationlosses Concentrated

Solar radiation

Work / Electricity

HeatRejected

Geometrical concentration ratio

• The geometrical concentration ratio, Cg, is defined as

Where Aabs is the receiver (or absorber) area and Ac is the collection area.

Absorption area

Concentrator

Collection area

Optical efficiency of the receiver

Ideal concentrator

• The maximum theoretical optical efficiency (when Tabs≥TSky) is the effective absorptivity of the receiver.

• The higher the concentrated solar flux (C*I), the better the optical efficiency.

• The higher the absorber temperature, the higher the radiative loss and, therefore, optical efficiency is lower.

• The higher the effective emissivity, ε, the lower the optical efficiency.

Global efficiency of the ideal concentrating system

Ideal concentrating system

• For each value of the geometrical concentration ratio, there is an optimum temperature.

• The higher the geometrical concentration ratio, the higher the optimum temperature and the global efficiency.

Concentration limits

• The Sun is not a point light source. Seen From the Earth, is a disk of apparent diameter θS ≈ 32’.

• The maximum concentration ratio is given by

Where n and n’ are the refractive indices of the media that the light crosses before and after the reflection on the concentrator surface

Other factors affecting real concentrators. Non ideal concentrator surface

2222cspSD

Ideal curvature

Spherical curvature, with waviness

Other factors affecting real concentrators. Sunshape

Types of concentrating systems

• Line focus (2D)– Parabolic troughs; CLFR

• Point focus (3D)– Central receiver systems,

parabolic concentrators (dishes)

SDmáxC 23, sin/1

SDmáxC sin/12,

Real concentrating systems

Theoretical

3D: < 46200

2D: < 215

Manuel A. Silva Pérez

silva@esi.us.es

Solar Thermal Power Plants

Solar thermal power

• 100 % renewable• Based on well known technologies:

– Materials• Steel• Mirrors• Water• Thermal oil• Molten salts• …

– Engineering• Electrical• Mechanical• Thermal…

Solar thermal power

• The “fuel” is beam solar radiation– Predictable within certain limits

• Storage and hybridization provide aditional basis for dispatchability

• Centralized or distributed generation

Solar thermal power has a very high potential of contribution to the

electricity system during the next decades

Solar Thermal Power Plant. Basic configuration

Beam irradiance

Concentrator

Receiver

Thermal Storage

Concentrated irradianceElectricity

Power conversion system

Thermal energy

BoilerFossil fuel Biomass

Main Concentrating Technologies

Central Receiver / Heliostats

Parabolic troughs

Parabolic dishes

Linear Fresnel Reflectors

Solar thermal power plants

Solar Thermal Concentrating systems for electricity (energy) generation

CSP in the Ancient times…

CSP in the modern times

CETS. Breve historia –Años 80: plantas de demostración

Recent history of CSP

Pontevedra, UNED, julio 2007

Other (unrealized) projects…

Solgas (1993-1996). Hybrid solar-gas cogeneration plant

Colón Solar (1997-1998). Integration of solar energy in a conventional power plant

Nevada Solar One (Boulder City, NV), 2006.

PS10 and PS20 (Seville, Spain). 2007 and 2009

Kimberlina (Bakersfield, CA), 2008.

Calasparra (Murcia, Spain) 2009.

Andasol 1 (Granada, Spain), 2009

Puertollano (Ciudad real, Spain), 2009

Sierra Sun Tower (California, USA) 2009

Maricopa Solar (Arizona, USA) 2009

…and many more to come during the next years

Concentrated Solar Power Course - Session 1 : Fundamentals

Technology