Modelling and standardization of yield analysis for …sfera.sollab.eu/...and_Standardization_Tobias_Hirsch_SFERA2013.pdf · Modelling and standardization of yield analysis for solar

Modelling and standardization of yield analysis forsolar thermal power plants

Tobias Hirsch, DLR Institute of Solar [email protected]

SFERA Summer School 2013, May 16, Hornberg, Germany

www.DLR.de/SF • Slide 2 > Modelling and standardization of solar thermal power plants > Tobias Hirsch > May 16, 2013

Contents

Why do we need standards?

The SolarPACES guiSmo project

Some illustrating examples

First a guideline then a standard

Conclusions and outlook

WP-2: Structural framework- Quality requirements

- pre-feasibility - project development- acceptance tests

- Solar technologies consid.trough, tower, dish …

- Nomenclature- technical terms- characteristic numbers

- Common framework- definition of sub-systems- definition of interfaces- basic requirements






WP-3: Component modeling- Description of physical effects- Modeling approaches- Default parameter sets


WP-8: Meteorological input- Interface to SolarPACES tasks- Meteo input data structure- Required temporal resolution


WP-4: Operation strategies- Methods to consider OP strat.- Reference OP strategies- Market boundary conditions


WP-9: Validation and Benchmarking- Validation of methods against operational data- Definition of benchmark standards (reference configurations)


WP-1: Coordination - founding of international working group- project definition (objectives, structure, schedule, finance)- official representation of the task


WP-7: Financial evaluation - Common methods- Collection of methods


WP-10: Communication infrastructure - WIKI system for day-to-day work- Way of publication for final hand book


WP-6: Uncertainties- CSP applicable methods- Relevant inputs


WP-5: Transient effects- Methods to tune steady-state

simulations- Default parameters




CSP plants world-wide

Estela World Map of CSP plantsLarge number of plants realized– without any standards for electricity yield estimation


A typical CSP plant

Andasol-TypeElectric power 50 MWStorage 7.5 hSolar field size 500.000 m2

Invest costs ~300 Mio €Financial structure

- Equity, possibly of different owners- Debt- (federal subsidies)

The sponsor of a 300 Mio € projectexpects a secure investment!


A thesis derived from daily practice …

Expected electricity production of a CSP plant determined by two independent experts based on the same meteo data varies by

+/- 10% if plant configuration is roughly defined+/- 5% after adjustment of the main components+/- 2% after a fine tuning

155 GWh 150 GWh

=1 Mio. € / year !With a tariff of 20 € ct/kWh


Reasons for the deviations

Different understanding of input and result figures Different modelling approaches

- Degree of model detail and accuracy- Choice of component parameters- Consideration of transient processes- Operation strategy

User errors, code errors

Up to now there is no accepted calculation procedure forthe yield estimation of solar thermal power plants!


Status in CSP project development today

All players have to cope with a certain level of uncertainty:- Try to fix parameters and input data as good as possible - Increase confidentiality by involving consultants - Foresee safety margins- Financial risk surcharges

The last three measures unnecessarily increase the cost of CSP plants!

Standardized yieldcalculation

Reducedelectricity costs


SolarPACES project guiSmoGuidelines for CSP Performance Modeling

- Founded in 2010 as a SolarPACES project- 115 registered participants from all over the world- Work in the project is based on voluntary contributions from research,

industry and banks

We will develop, document and publish guidelines for CSP performance modeling in international collaboration!


Who will benefit from a standard?

Investors Higher reliabilityComparability of projectsReduction of overall costs

EPC ContractorsAccuracy of results, reduced uncertaintyApplication of quality standard as a sales argumentReduced effort for development of proprietary methods

Project DevelopersMake use of best method available for yield analysisSpeed up development and marketing of projectsAssess different technological approaches

INABENSAInstalaciones Abengoa, S.A.

-…


Who will benefit from a standard?

ConsultantsIncreased credibilityReduced effort for development of proprietary methods

„Capacity Building“Methods easy to apply for engineersSimplifies start-up of new companies

ResearchEarly comparability of new technological approachesReduce non-research due diligence activities


SolarPACES project guiSmoWorkpackageStructure































Work in progress


Definition of quality levels

Hirsch et al. Standardization of CSP Performance Model Projection-Latest Results from theStamp Project. Proc. ASME Energy Sustainability conference 2011, Washington, D.C.


Definition of sub-systems

Input(e.g. DNI)

Output(e.g. Electricity/y)


Definition of Sub-Systems

Input(e.g. DNI)

Output(e.g. Electricity/y)

1. Traceability → Transparency2. Reduced complexity → Sub-systems3. User Guidance → Conventions

(interfaces, parameters,…)


Definition of Sub-Systems


Interfaces between Sub-Systems

fixed inputs:parameters

Results:Characteristic variables

model equations

technology specific

model specific

sub-systemspecific

technology specific

Interface variablessub-systemspecific

model specific

defined bystructuralframework

defined in the individualmodelingwork packages

Data exchange with the other sub-systems only via interface variables


Having a common understanding of terms …Example: Azimuth angle

Azimuth angle defines orientation of collector

Various definitions are used today:- Use collector axis or aperture normal

as reference?- Count angle from north or from south?- Different on northern and southern

hemisphere?

A standard is not just a project report!


Having a common understanding of terms …Example: Net aperture area

How to define a net aperture area?- Projection of reflective surface into aperture plane

(without gaps between mirror facets)- Shadow of absorber tube to be subtracted?- Directly irradiated side of absorber to be added?

This is a definition for a parabolic trough system but what about …


Having a common understanding of terms …Example: Net aperture area

- Projection into horizontal plane, but under whichmirror facet position?

- tracked mirrors for sun in zenith- mirrors looking vertically upwards (virtual!)

- Shadow of receiver on reflective surfacechanges with sun position

- Back side of receiver is not directly irradiated.

Agreement under experts can be easily found for one technology, butit should be consistent with other CSP technologies, too!


Giving flexibility to different modelling approachesExample: Heat losses of a PT system

Approach 1:Detailed physical

heat transfer model

Approach 3:Performance curve

for a whole loop

Approach 2:Heat loss curvefor a collector


Giving flexibility to different modelling approachesConclusions for the guidelines- What the handbook should provide:

- Clear definition of input and output variables- Definition of important intermediate results - One or more detailed modelling approach(es) including a discussion- Default parameters for modelling approaches (reference for model

comparisons)- Support for quality check

(typical curves, typical errors, benchmark data)


Definition of operation strategy

Electricity yield and especially financial revenues are influenced by the operation strategy

One plantconfiguration = One output


Definition of operation strategyConclusions for the guidelines- What the handbook should provide:

- Definition for default operation strategies (solar driven, 24 h, …)- Methodology to document alternate operation strategies in a yield

calculation report- Estimation of the difference between operation strategies


Uncertainties in parameters and inputs

Sources of uncertainties:- Parameters of components not fixed in early project development- Materials and manufacturing tolerance of components- Uncertainties in operating strategies

Probability density functions- type of distribution?- parameters?


Uncertainties in parameters and inputsExample: 64 MW parabolic trough plant in USA

00.1

0.2

0.30.4

0.5

0.60.7

0.8

0.9

1

80,000 90,000 100,000 110,000 120,000Annual Electric generation (MWh/yr)

Cum

ulat

ive

Pro

babi

lity

113,409 MWh/yr(deterministic)

91,150 to 115,550 MWh/yr

90 %

con

fiden

ce

Example by Cliff Ho, SolarPACES task I meeting, Granada, February 22, 2011


Uncertainties in parameters and inputsConclusions for the guidelines- Methodology to determine uncertainties is required- Uncertainty distributions of at least the key parameters- Uncertainty distributions of the inputs (especially irradiance data)- Method to estimate the uncertainty of the model itself


SolarPACES project guiSmoWorkpackageStructure































Work in progress


First a handbook – then a standard

Founding ofInternational

Working Group

Autumn 2010

Handbook of CSP Yield Analysis

1st draft

2014?

InternationalStandards

Beyond 2015Handbook of CSP Yield Analysis

2015?


What is a technical standard?

A technical standard is an established norm or requirement in regard to technical systems. It is usually a formal document that establishes uniform engineering or technical criteria, methods, processes and practices.

A technical standard may be developed privately or unilaterally, for example by a corporation, regulatory body, military, etc. Standards can also be developed by groups such as trade unions, and trade associations. Standards organizations often have more diverse input and usually develop voluntary standards: these might become mandatory if adopted by a government, business contract, etc.

excerpt from wikipedia.org


International standardization bodies

IEC, Geneva

TC 117Solar thermal electric plants

AHG 1 AHG 2 AHG 3

International ElectrotechnicalCommission

ISO, Geneva

International Organisation for Standardization

ITU, Geneva

International Telecommunication Union

e.g. ISO 9001

All issues in the field ofelectro-technics

All issues in the field oftelecommunication

All remaining fields


Standardization bodies

Aenor(span. standardization

institution)

IEC*, Geneva

VDE-DKE(german standard. instit.)

CENELEC


AEN/CTN 206Production de energia

electrica

DKE/K 374Solarthermische Anlagen

zur Stromerzeugung

Workinggroup

Workinggroup

AHG 1 AHG 2 AHG 3

Working groups

CLC/SR 117Solar thermal electric plants

International Electrotechnical Commission, „IEC“

Germany „DIN“

e.g. DIN EN ISO 9488 „Solar energy vocabulary“

Spain „UNE“

Working groups

National translations

European Committeefor ElectrotechnicalStandardization „EN“


IEC/TC 117 “Solar thermal electric plants“

Mrs Begoña Barnechea ESMr Chris Flueckiger USMr Matthias Gommel DEMs Lourdes González Martínez ESMr Eckhard Lüpfert DEMr Oliver Mayer DEMr Richard Meyer DEMr Gabriel Morin DEMr Kazuo Shibata JPMr Kazuo YOSHIDA JPMr Eduardo Zarza Moya ES

AHG 1: General subjects

AHG 2: Systems and components

Mr Hagai Aran ILMr Héctor Barroso ESMr Tommy Carlsson SEMr Ehud Epstein ILMr Kazuaki Ezawa JPMr Rami Ezer ILMs Aránzazu Fernández García ESMr Jesús Fernández Reche ESMr Eduardo García Iglesias ESMr Matthias Gommel DEMr Miguel Herrador Moreno ESMr Stefan Hiemer DEMr Eckhard Lüpfert DEMr Gabriel Morin DEMr Kenji Oda JPMr Miguel Palomo ESMs Yafit Zoltak Raz ILMr Frank Rodríguez ESMr Fabienne Sallaberry ESMs Gema San Vicente Domingo ESMr Marcelino Sánchez ESMrs Patricia Santamaria ESMr Enrique Serrano ESMr Kazuo Shibata JPMs Loreto Valenzuela Gutiérrez ESMr Kazuo YOSHIDA JP


Co-operation between guiSmo and IEC etc.


AEN/CTN 206Production de energia

electrica

DKE/K 374Solarthermische Anlagen

zur Stromerzeugung

SolarPACESguiSmo

Nationalactivities

Nationalactivities

Liaisons

SolarPACES guiSmo is the scientificexpert group working out proposals.


Standards for electricity yield calculationsSummary and conclusions

- Elaborate technologies require standards- Yield estimation for CSP plants is key aspect in project development- Guidelines or standards are required by the different players- SolarPACES guiSmo is the starting point for activities in this field- Standardization organizations are open for new proposals

- There is a lot of work ahead …

Documents

Modelling and standardization of yield analysis for …sfera.sollab.eu/...and_Standardization_Tobias_Hirsch_SFERA2013.pdf · Modelling and standardization of yield analysis for solar