@inproceedings{SchulteSchwagerFrantzetal.2022,
  author    = {Schulte, Jonas and Schwager, Christian and Frantz, Cathy and Schloms, Felix and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Control concept for a molten salt receiver in star design: Development, optimization and testing with cloud passage scenarios},
  series = {SolarPACES 2022 conference proceedings},
  booktitle = {SolarPACES 2022 conference proceedings},
  number    = {1},
  publisher = {TIB Open Publishing},
  address   = {Hannover},
  issn      = {2751-9899 (online)},
  doi       = {10.52825/solarpaces.v1i.693},
  pages     = {9 Seiten},
  year      = {2022},
  abstract  = {A promising approach to reduce the system costs of molten salt solar receivers is to enable the irradiation of the absorber tubes on both sides. The star design is an innovative receiver design, pursuing this approach. The unconventional design leads to new challenges in controlling the system. This paper presents a control concept for a molten salt receiver system in star design. The control parameters are optimized in a defined test cycle by minimizing a cost function. The control concept is tested in realistic cloud passage scenarios based on real weather data. During these tests, the control system showed no sign of unstable behavior, but to perform sufficiently in every scenario further research and development like integrating Model Predictive Controls (MPCs) need to be done. The presented concept is a starting point to do so.},
  language  = {en}
}
@inproceedings{LahrsKrisamHerrmann2023,
  author    = {Lahrs, Lennart and Krisam, Pierre and Herrmann, Ulf},
  title     = {Envisioning a collaborative energy system planning platform for the energy transition at the district level},
  series = {ECOS 2023. The 36th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems},
  booktitle = {ECOS 2023. The 36th International Conference on Efficiency, Cost, Optimization, Simulation and Environmental Impact of Energy Systems},
  publisher = {Procedings of ECOS 2023},
  doi       = {10.52202/069564-0284},
  pages     = {3163 -- 3170},
  year      = {2023},
  abstract  = {Residential and commercial buildings account for more than one-third of global energy-related greenhouse gas emissions. Integrated multi-energy systems at the district level are a promising way to reduce greenhouse gas emissions by exploiting economies of scale and synergies between energy sources. Planning district energy systems comes with many challenges in an ever-changing environment. Computational modelling established itself as the state-of-the-art method for district energy system planning. Unfortunately, it is still cumbersome to combine standalone models to generate insights that surpass their original purpose. Ideally, planning processes could be solved by using modular tools that easily incorporate the variety of competing and complementing computational models. Our contribution is a vision for a collaborative development and application platform for multi-energy system planning tools at the district level. We present challenges of district energy system planning identified in the literature and evaluate whether this platform can help to overcome these challenges. Further, we propose a toolkit that represents the core technical elements of the platform. Lastly, we discuss community management and its relevance for the success of projects with collaboration and knowledge sharing at their core.},
  language  = {en}
}
@inproceedings{SauerbornLiebenstundRaueetal.2017,
  author    = {Sauerborn, Markus and Liebenstund, Lena and Raue, Markus and Mang, Thomas and Herrmann, Ulf and Dueing, Andreas},
  title     = {Analytic method for material aging and quality analyzing to forecast long time stability of plastic micro heliostat components},
  series = {AIP Conference Proceedings},
  volume    = {1850},
  booktitle = {AIP Conference Proceedings},
  number    = {1},
  doi       = {10.1063/1.4984388},
  pages     = {030045-1 -- 030045-8},
  year      = {2017},
  language  = {en}
}
@inproceedings{SchornWeisAnthrakidisetal.2016,
  author    = {Schorn, Christian and Weis, Fabian and Anthrakidis, Anette and Schwarzer, Klemens and Schmitz, Mark and Herrmann, Ulf},
  title     = {Entwicklung und Bewertung eines Parabolrinnenkollektors zur Prozessw{\"a}rmebereitstellung},
  series = {26. Symposium Thermische Solarenergie, 20.-22.04.2016 in Bad Staffelstein},
  booktitle = {26. Symposium Thermische Solarenergie, 20.-22.04.2016 in Bad Staffelstein},
  pages     = {1 -- 13},
  year      = {2016},
  language  = {de}
}
@article{SchwagerFleschSchwarzboezletal.2022,
  author    = {Schwager, Christian and Flesch, Robert and Schwarzb{\"o}zl, Peter and Herrmann, Ulf and Teixeira Boura, Cristiano Jos{\´e}},
  title     = {Advanced two phase flow model for transient molten salt receiver system simulation},
  series = {Solar Energy},
  volume    = {232},
  journal   = {Solar Energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0038-092X (print)},
  doi       = {10.1016/j.solener.2021.12.065},
  pages     = {362 -- 375},
  year      = {2022},
  abstract  = {In order to realistically predict and optimize the actual performance of a concentrating solar power (CSP) plant sophisticated simulation models and methods are required. This paper presents a detailed dynamic simulation model for a Molten Salt Solar Tower (MST) system, which is capable of simulating transient operation including detailed startup and shutdown procedures including drainage and refill. For appropriate representation of the transient behavior of the receiver as well as replication of local bulk and surface temperatures a discretized receiver model based on a novel homogeneous two-phase (2P) flow modelling approach is implemented in Modelica Dymola®. This allows for reasonable representation of the very different hydraulic and thermal properties of molten salt versus air as well as the transition between both. This dynamic 2P receiver model is embedded in a comprehensive one-dimensional model of a commercial scale MST system and coupled with a transient receiver flux density distribution from raytracing based heliostat field simulation. This enables for detailed process prediction with reasonable computational effort, while providing data such as local salt film and wall temperatures, realistic control behavior as well as net performance of the overall system. Besides a model description, this paper presents some results of a validation as well as the simulation of a complete startup procedure. Finally, a study on numerical simulation performance and grid dependencies is presented and discussed.},
  language  = {en}
}
@incollection{HebelHerrmannRitzetal.2022,
  author    = {Hebel, Christoph and Herrmann, Ulf and Ritz, Thomas and R{\"o}th, Thilo and Anthrakidis, Anette and B{\"o}ker, J{\"o}rg and Franzke, Till and Grodzki, Thomas and Merkens, Torsten and Sch{\"o}ttler, Mirjam},
  title     = {FlexSHARE - Methodisches Framework zur innovativen Gestaltung der urbanen Mobilit{\"a}t durch Sharing- Angebote},
  series = {Transforming Mobility - What Next?},
  booktitle = {Transforming Mobility - What Next?},
  publisher = {Springer Gabler},
  address   = {Wiesbaden},
  isbn      = {978-3-658-36429-8},
  doi       = {10.1007/978-3-658-36430-4_10},
  pages     = {153 -- 169},
  year      = {2022},
  abstract  = {Das Ziel des INTERREG-Projektes „SHAREuregio" (FKZ: 34.EFRE-0300134) ist es, grenz{\"u}berschreitende Mobilit{\"a}t in der Euregio Rhein-Maas-Nord zu erm{\"o}glichen und zu f{\"o}rdern. Dazu soll ein elektromobiles Car- und Bikesharing- System entwickelt und in der Stadt M{\"o}nchengladbach, im Kreis Viersen sowie in den Gemeinden Roermond und Venlo (beide NL) zusammen mit den Partnern Wirtschaftsf{\"o}rderung M{\"o}nchengladbach, Wirtschaftsf{\"o}rderung f{\"u}r den Kreis Viersen, NEW AG, Goodmoovs (NL), Greenflux (NL) und der FH Aachen implementiert werden. Zun{\"a}chst richtet sich das Angebot, bestehend aus 40 Elektroautos und 40 Elektrofahrr{\"a}dern, an Unternehmen und wird nach einer Erprobungsphase, mit einer gr{\"o}ßeren Anzahl an Fahrzeugen, auch f{\"u}r Privatpersonen verf{\"u}gbar gemacht werden. Die Fahrzeuge stehen bei den jeweiligen Anwendungspartnern in Deutschland und den Niederlanden. Im Rahmen dieses Projektes hat die FH Aachen „FlexSHARE" entwickelt - ein methodisches Framework zur innovativen Gestaltung urbaner Sharing- Angebote. Das Framework erm{\"o}glicht es, anhand von messbaren Kenngr{\"o}ßen, bedarfsgerechte und auf die Region abgestimmte Sharing-Systeme zu entwickeln.},
  language  = {de}
}
@inproceedings{AnthrakidisHerrmannSchornetal.2015,
  author    = {Anthrakidis, Anette and Herrmann, Ulf and Schorn, Christian and Schwarzer, Klemens and Wedding, Philipp},
  title     = {Weiterentwicklung und Erprobung eines neuartigen Verfahrens zur Bestimmung der Effizienz von konzentrierenden solarthermischen Kollektoren},
  series = {25. OTTI Symposium Thermische Solarenergie},
  booktitle = {25. OTTI Symposium Thermische Solarenergie},
  pages     = {15 Seiten},
  year      = {2015},
  language  = {de}
}
@incollection{HerrmannKearneyRoegeretal.2017,
  author    = {Herrmann, Ulf and Kearney, D. and R{\"o}ger, M. and Prahl, C.},
  title     = {System performance measurements},
  series = {The Performance of Concentrated Solar Power (CSP) Systems : Modelling, Measurement and Assessment},
  booktitle = {The Performance of Concentrated Solar Power (CSP) Systems : Modelling, Measurement and Assessment},
  publisher = {Woodhead Publishing},
  address   = {Duxford},
  isbn      = {978-0-08-100448-7},
  doi       = {https://doi.org/10.1016/B978-0-08-100447-0.00005-5},
  pages     = {115 -- 165},
  year      = {2017},
  abstract  = {This chapter introduces performance and acceptance testing and describes state-of-the-art tools, methods, and instruments to assess the plant performance or realize plant acceptance testing. The status of the development of standards for performance assessment is given.},
  language  = {en}
}
@inproceedings{AnthrakidisHerrmannMirzaetal.2014,
  author    = {Anthrakidis, Anette and Herrmann, Ulf and Mirza, M. F. and Schorn, Christian and Schwarzer, Klemens and Wedding, Philipp and Weis, Fabian},
  title     = {Parabolrinnenentwicklung und Qualifizierung am Solar-Institut J{\"u}lich},
  series = {Thermische Solarenergie : 24. Symposium ; 7. bis 9. Mai 2014, Kloster Banz, Bad Staffelstein},
  booktitle = {Thermische Solarenergie : 24. Symposium ; 7. bis 9. Mai 2014, Kloster Banz, Bad Staffelstein},
  publisher = {OTTI},
  address   = {Regensburg},
  organization    = {Ostbayerisches Technologie-Transfer-Institut},
  isbn      = {978-3-943891-35-5},
  pages     = {242 -- 243},
  year      = {2014},
  language  = {de}
}
@inproceedings{MayBreitbachAlexopoulosetal.2019,
  author    = {May, Martin and Breitbach, Gerd and Alexopoulos, Spiros and Latzke, Markus and B{\"a}umer, Klaus and Uhlig, Ralf and S{\"o}hn, Matthias and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Experimental facility for investigations of wire mesh absorbers for pressurized gases},
  series = {AIP Conference Proceedings},
  volume    = {2126},
  booktitle = {AIP Conference Proceedings},
  issn      = {0094243X},
  doi       = {10.1063/1.5117547},
  pages     = {030035-1 -- 030035-9},
  year      = {2019},
  language  = {en}
}
@article{HerrmannSchwarzenbartDittmannGabriel2019,
  author    = {Herrmann, Ulf and Schwarzenbart, Marc and Dittmann-Gabriel, S{\"o}ren},
  title     = {Speicher statt Kohle. Integration thermischer Stromspeicher in vorhandene Kraftwerksstandorte},
  series = {BWK : Das Energie-Fachmagazin},
  volume    = {71},
  journal   = {BWK : Das Energie-Fachmagazin},
  number    = {4},
  publisher = {Springer-VDI-Verl.},
  address   = {D{\"u}sseldorf},
  issn      = {1436-4883},
  pages     = {42 -- 45},
  year      = {2019},
  language  = {de}
}
@inproceedings{SchwagerTeixeiraBouraFleschetal.2019,
  author    = {Schwager, Christian and Teixeira Boura, Cristiano Jos{\´e} and Flesch, Robert and Alexopoulos, Spiros and Herrmann, Ulf},
  title     = {Improved efficiency prediction of a molten salt receiver based on dynamic cloud passage simulation},
  series = {AIP Conference Proceedings},
  volume    = {2126},
  booktitle = {AIP Conference Proceedings},
  number    = {1},
  isbn      = {978-0-7354-1866-0},
  doi       = {10.1063/1.5117566},
  pages     = {030054-1 -- 030054-8},
  year      = {2019},
  language  = {en}
}
@article{KearneyHerrmannNavaetal.2003,
  author    = {Kearney, D. and Herrmann, Ulf and Nava, P. and Kelly, B. and Mahoney, R. and Pacheco, J. and Cable, R. and Potrovitza, N. and Blake, D. and Price, H.},
  title     = {Assessment of a Molten Salt Heat Transfer Fluid in a Parabolic Trough Solar Field},
  series = {Journal of Solar Energy Engineering},
  volume    = {125},
  journal   = {Journal of Solar Energy Engineering},
  number    = {2},
  issn      = {1528-8986},
  doi       = {10.1115/1.1565087},
  pages     = {170 -- 176},
  year      = {2003},
  language  = {en}
}
@inproceedings{TeixeiraBouraNiederwestbergMcLeodetal.2016,
  author    = {Teixeira Boura, Cristiano Jos{\´e} and Niederwestberg, Stefan and McLeod, Jacqueline and Herrmann, Ulf and Hoffschmidt, Bernhard},
  title     = {Development of heat exchanger for high temperature energy storage with bulk materials},
  series = {AIP Conference Proceedings},
  volume    = {1734},
  booktitle = {AIP Conference Proceedings},
  number    = {1},
  doi       = {10.1063/1.4949106},
  pages     = {050008-1 -- 050008-7},
  year      = {2016},
  language  = {en}
}
@inproceedings{SchulteSchwagerNoureldinetal.2023,
  author    = {Schulte, Jonas and Schwager, Christian and Noureldin, Kareem and May, Martin and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Gradient controlled startup procedure of a molten-salt power-to-heat energy storage plant based on dynamic process simulation},
  series = {SolarPACES: Solar Power \& Chemical Energy Systems},
  booktitle = {SolarPACES: Solar Power \& Chemical Energy Systems},
  number    = {2815 / 1},
  publisher = {AIP conference proceedings / American Institute of Physics},
  address   = {Melville, NY},
  isbn      = {978-0-7354-4623-6},
  issn      = {1551-7616 (online)},
  doi       = {10.1063/5.0148741},
  pages     = {9 Seiten},
  year      = {2023},
  abstract  = {The integration of high temperature thermal energy storages into existing conventional power plants can help to reduce the CO2 emissions of those plants and lead to lower capital expenditures for building energy storage systems, due to the use of synergy effects [1]. One possibility to implement that, is a molten salt storage system with a powerful power-to-heat unit. This paper presents two possible control concepts for the startup of the charging system of such a facility. The procedures are implemented in a detailed dynamic process model. The performance and safety regarding the film temperatures at heat transmitting surfaces are investigated in the process simulations. To improve the accuracy in predicting the film temperatures, CFD simulations of the electrical heater are carried out and the results are merged with the dynamic model. The results show that both investigated control concepts are safe regarding the temperature limits. The gradient controlled startup performed better than the temperature-controlled startup. Nevertheless, there are several uncertainties that need to be investigated further.},
  language  = {en}
}
@inproceedings{RendonDieckmannWeidleetal.2018,
  author    = {Rendon, Carlos and Dieckmann, Simon and Weidle, Mathias and Dersch, J{\"u}rgen and Teixeira Boura, Cristiano Jos{\´e} and Polklas, Thomas and Kuschel, Marcus and Herrmann, Ulf},
  title     = {Retrofitting of existing parabolic trough collector power plants with molten salt tower systems},
  series = {AIP Conference Proceedings},
  volume    = {2033},
  booktitle = {AIP Conference Proceedings},
  number    = {1},
  doi       = {10.1063/1.5067030},
  pages     = {030014-1 -- 030014-8},
  year      = {2018},
  language  = {en}
}
@inproceedings{SattlerAlexopoulosChicoCaminosetal.2019,
  author    = {Sattler, Johannes Christoph and Alexopoulos, Spiros and Chico Caminos, Ricardo Alexander and Mitchell, John C. and Ruiz, Victor C. and Kalogirou, Soteris and Ktistis, Panayiotis K. and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Dynamic simulation model of a parabolic trough collector system with concrete thermal energy storage for process steam generation},
  series = {AIP Conference Proceedings},
  volume    = {2126},
  booktitle = {AIP Conference Proceedings},
  issn      = {0094243X},
  doi       = {10.1063/1.5117663},
  pages     = {150007-1 -- 150007-8},
  year      = {2019},
  language  = {en}
}
@inproceedings{AnthrakidisHerrmannSchornetal.2015,
  author    = {Anthrakidis, Anette and Herrmann, Ulf and Schorn, Christian and Schwarzer, Klemens and Wedding, Philipp and Weis, Fabian},
  title     = {Development and Testing of a Novel Method for the Determination of the Efficiency of Concentrating Solar Thermal Collectors},
  series = {Conference Proceedings Solar World Congress 2015, Daegu, Korea, 08 - 12 November 2015},
  booktitle = {Conference Proceedings Solar World Congress 2015, Daegu, Korea, 08 - 12 November 2015},
  pages     = {9 Seiten},
  year      = {2015},
  language  = {en}
}
@inproceedings{HerrmannWorringerGraeteretal.2006,
  author    = {Herrmann, Ulf and Worringer, S. and Graeter, F. and Nava, P.},
  title     = {Three Years of Operation Experience of the SKAL-ET Collector Loop at SEGS V},
  series = {13th International Symposium Concentrated Solar Power and Chemical Energy Technologies, June 20 - 23, 2006, Seville, Spain},
  booktitle = {13th International Symposium Concentrated Solar Power and Chemical Energy Technologies, June 20 - 23, 2006, Seville, Spain},
  editor    = {Romero, Manuel},
  publisher = {SolarPACES [u.a.]},
  address   = {[s.l.]},
  isbn      = {84-7834-519-1},
  pages     = {1 CD-ROM},
  year      = {2006},
  language  = {en}
}
@inproceedings{HerrmannGraeterNava2004,
  author    = {Herrmann, Ulf and Graeter, F. and Nava, P.},
  title     = {Performance of the SKAL-ET Collector Loop at KJC Operating Company},
  series = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12},
  booktitle = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12},
  editor    = {Ramos, C.},
  publisher = {Instituto de Investigaciones Electricas},
  address   = {[s.l.]},
  isbn      = {968-6114-18-1},
  year      = {2004},
  language  = {en}
}
@inproceedings{SchulteFischedickTammeHerrmann2009,
  author    = {Schulte-Fischedick, Jan and Tamme, Rainer and Herrmann, Ulf},
  title     = {CFD Analysis of the Cool Down Behaviour of Molten Salt Thermal Storage Systems},
  series = {ASME 2008 2nd International Conference on Energy Sustainability collocated with the Heat Transfer, Fluids Engineering, and 3rd Energy Nanotechnology Conferences, ASME 2008 2nd International Conference on Energy Sustainability, Jacksonville, Florida, USA, August 10-14, 2008. - Vol. 2},
  booktitle = {ASME 2008 2nd International Conference on Energy Sustainability collocated with the Heat Transfer, Fluids Engineering, and 3rd Energy Nanotechnology Conferences, ASME 2008 2nd International Conference on Energy Sustainability, Jacksonville, Florida, USA, August 10-14, 2008. - Vol. 2},
  publisher = {ASME},
  address   = {New York, NY},
  isbn      = {978-0-7918-4320-8},
  doi       = {doi:10.1115/ES2008-54101},
  pages     = {515 -- 524},
  year      = {2009},
  language  = {de}
}
@article{HerrmannKellyPrice2002,
  author    = {Herrmann, Ulf and Kelly, Bruce and Price, Henry},
  title     = {Two Tank Molten Salt Storage for Parabolic Trough Solar Power Plants},
  series = {Energy : the international journal},
  volume    = {29},
  journal   = {Energy : the international journal},
  number    = {5-6 (Special Issue SolarPaces)},
  issn      = {0360-5442},
  doi       = {10.1016/S0360-5442(03)00193-2},
  pages     = {883 -- 893},
  year      = {2002},
  language  = {en}
}
@article{HerrmannSchwarzenbartDittmannGabrieletal.2019,
  author    = {Herrmann, Ulf and Schwarzenbart, Marc and Dittmann-Gabriel, S{\"o}ren and May, Martin},
  title     = {Hochtemperatur-W{\"a}rmespeicher f{\"u}r die Strom- und W{\"a}rmewende},
  series = {Solarzeitalter : Politik, Kultur und {\"O}konomie erneuerbarer Energien},
  volume    = {31},
  journal   = {Solarzeitalter : Politik, Kultur und {\"O}konomie erneuerbarer Energien},
  number    = {2},
  issn      = {0937-3802},
  pages     = {18 -- 23},
  year      = {2019},
  language  = {de}
}
@article{DerschGeyerHerrmannetal.2004,
  author    = {Dersch, J{\"u}rgen and Geyer, Michael and Herrmann, Ulf and Jones, Scott A. and Kelly, Bruce and Kistner, Rainer and Ortmanns, Winfried and Pitz-Paal, Robert and Price, Henry},
  title     = {Trough integration into power plants—a study on the performance and economy of integrated solar combined cycle systems},
  series = {Energy : the international journal},
  volume    = {29},
  journal   = {Energy : the international journal},
  number    = {5-6 (Special Issue SolarPaces)},
  issn      = {0360-5442},
  doi       = {10.1016/S0360-5442(03)00199-3},
  pages     = {947 -- 959},
  year      = {2004},
  language  = {en}
}
@inproceedings{AringhoffGeyerHerrmannetal.2002,
  author    = {Aringhoff, R. and Geyer, Michael and Herrmann, Ulf and Kistner, Rainer and Nava, P. and Osuna, R.},
  title     = {AndaSol : 50MW Solar Plants with 9 Hour Storage for Southern Spain},
  series = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  booktitle = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  editor    = {Steinfeld, Aldo},
  publisher = {Paul Scherrer Inst.},
  address   = {Villingen},
  isbn      = {3-9521409-3-7},
  pages     = {37 -- 42},
  year      = {2002},
  language  = {en}
}
@inproceedings{HerrmannKellyPrice2002,
  author    = {Herrmann, Ulf and Kelly, Bruce and Price, Henry},
  title     = {Two Tank Molten Salt Storage for Parabolic Trough Solar Power Plants},
  series = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  booktitle = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  editor    = {Steinfeld, Aldo},
  publisher = {Paul Scherrer Inst.},
  address   = {Villingen},
  isbn      = {3-9521409-3-7},
  pages     = {517 -- 524},
  year      = {2002},
  language  = {en}
}
@inproceedings{JanotteFecklerKoetteretal.2014,
  author    = {Janotte, N. and Feckler, G. and K{\"o}tter, Jens and Decker, Stefan and Herrmann, Ulf and Schmitz, Mark and L{\"u}pfert, E.},
  title     = {Dynamic performance evaluation of the HelioTrough® collector demonstration loop : towards a new benchmark in parabolic trough qualification},
  series = {SolarPACES International Conference 2013, Las Vegas, Nevada, USA, 17 - 20 September 2013 : [proceedings]. - Pt. 1. - (Energy procedia ; 49)},
  booktitle = {SolarPACES International Conference 2013, Las Vegas, Nevada, USA, 17 - 20 September 2013 : [proceedings]. - Pt. 1. - (Energy procedia ; 49)},
  publisher = {Curran},
  address   = {Red Hook, NY},
  isbn      = {978-1-63266-904-9},
  issn      = {1876-6102},
  doi       = {10.1016/j.egypro.2014.03.012},
  pages     = {109 -- 117},
  year      = {2014},
  language  = {en}
}
@inproceedings{KoetterDeckerDetzleretal.2012,
  author    = {K{\"o}tter, Jens and Decker, Stefan and Detzler, Raphael and Sch{\"a}fer, Jochen and Schmitz, Mark and Herrmann, Ulf},
  title     = {Cost Reduction of Solar Fields with HelioTrough Collector},
  publisher = {FLAGSOL},
  address   = {K{\"o}ln},
  pages     = {9 S. : Ill., graph. Darst.},
  year      = {2012},
  language  = {en}
}
@inproceedings{AjonaHerrmannSperdutoetal.1996,
  author    = {Ajona, J. I. and Herrmann, Ulf and Sperduto, F. and Farinha-Mendes, J.},
  title     = {Main Achievements within ARDISS (Advanced Receiver for Direct Solar Steam Production in Parabolic Trough Solar Power Plants) Project},
  series = {Components, tools, facilities and measurement techniques. - (Solar thermal concentrating technologies : proceedings of the 8th international symposium, October, 6 - 11, 1996, K{\"o}ln, Germany ; Vol. 2)},
  booktitle = {Components, tools, facilities and measurement techniques. - (Solar thermal concentrating technologies : proceedings of the 8th international symposium, October, 6 - 11, 1996, K{\"o}ln, Germany ; Vol. 2)},
  editor    = {Becker, Manfred},
  publisher = {M{\"u}ller},
  address   = {Heidelberg},
  isbn      = {3-7880-7616-X},
  pages     = {733 -- 754},
  year      = {1996},
  language  = {en}
}
@phdthesis{Herrmann2004,
  author    = {Herrmann, Ulf},
  title     = {Untersuchungen zur Rohrwandbenetzung bei der Dampferzeugung in horizontalen und geneigten Parabolrinnen-Solarkollektoren. - (FLAGSOL Forschungsbericht)},
  publisher = {FLAGSOL},
  address   = {K{\"o}ln},
  isbn      = {3-9804901-2-2},
  pages     = {IX, 145 S. : Ill., graph. Darst.},
  year      = {2004},
  language  = {de}
}
@inproceedings{BlakeMoensHaleetal.2002,
  author    = {Blake, D. and Moens, L. and Hale, M.-J. and Price, Henry and Keaney, David W. and Herrmann, Ulf},
  title     = {New heat transfer and storage fluids for parabolic trough solar thermal electric plants},
  series = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  booktitle = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  editor    = {Steinfeld, Aldo},
  publisher = {Paul Scherrer Inst.},
  address   = {Villingen},
  isbn      = {3-9521409-3-7},
  pages     = {63 -- 66},
  year      = {2002},
  language  = {en}
}
@inproceedings{KellyHerrmannHale2001,
  author    = {Kelly, Bruce and Herrmann, Ulf and Hale, M.-J.},
  title     = {Optimization Studies for Integrated Solar Combined Cycle Systems},
  series = {Solar engineering 2001 : proceedings of the International Solar Energy Conference ; presented at the 2001 International Solar Energy Conference, a part of Forum 2001 - Solar energy: the power to choose, April 21 - 25, 2001, Washington, D.C.},
  booktitle = {Solar engineering 2001 : proceedings of the International Solar Energy Conference ; presented at the 2001 International Solar Energy Conference, a part of Forum 2001 - Solar energy: the power to choose, April 21 - 25, 2001, Washington, D.C.},
  publisher = {ASME},
  address   = {New York, NY},
  isbn      = {0-7918-1670-2},
  pages     = {393 -- 398},
  year      = {2001},
  language  = {en}
}
@inproceedings{DerschGeyerHerrmannetal.2002,
  author    = {Dersch, J{\"u}rgen and Geyer, Michael and Herrmann, Ulf and Jones, Scott A. and Kelly, Bruce and Kistner, Rainer and Ortmanns, Winfried and Pitz-Paal, Robert and Price, Henry},
  title     = {Trough integration into power plants : a study on the performance and economy of integrated solar combined cycle systems},
  series = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  booktitle = {Proceedings of the 11th SolarPACES International Symposium on Concentrated Solar Power and Chemical Energy Technologies : September 4 - 6, 2002, Zurich, Switzerland / Paul Scherrer Institut, PSI; ETH, Eidgen{\"o}ssische Technische Hochschule Z{\"u}rich},
  editor    = {Steinfeld, Aldo},
  publisher = {Paul Scherrer Inst.},
  address   = {Villingen},
  isbn      = {3-9521409-3-7},
  pages     = {661 -- 671},
  year      = {2002},
  language  = {en}
}
@inproceedings{HahneHerrmannRheinlaender1997,
  author    = {Hahne, E. and Herrmann, Ulf and Rheinl{\"a}nder, J.},
  title     = {The Effect of Tilt on Flow Pattern of Water/Steam Flow Through Heated Tubes},
  series = {Experimental heat transfer, fluid mechanics and thermodynamics 1997 : proceedings of the 4th World Conference on Experimental Heat Transfer, Fluid Mechanics and Thermodynamics, Brussels, June 2 - 6, 1997. - Vol. 2},
  booktitle = {Experimental heat transfer, fluid mechanics and thermodynamics 1997 : proceedings of the 4th World Conference on Experimental Heat Transfer, Fluid Mechanics and Thermodynamics, Brussels, June 2 - 6, 1997. - Vol. 2},
  editor    = {Girot, Michel},
  publisher = {Ed. ETS},
  address   = {Pisa},
  isbn      = {88-467-0014-7},
  pages     = {925 -- 934},
  year      = {1997},
  language  = {en}
}
@inproceedings{DerschGeyerHerrmannetal.2002,
  author    = {Dersch, J{\"u}rgen and Geyer, Michael and Herrmann, Ulf and Jones, Scott A. and Kelly, Bruce and Kistner, Rainer and Ortmanns, Winfried and Pitz-Paal, Robert and Price, Henry},
  title     = {Solar Trough Integration Into Combined Cycle Systems},
  series = {Solar engineering 2002 : proceedings of the International Solar Energy Conference ; presented at the 2002 International Solar Energy Conference, a part of Solar 2002 - Sunrise on the Reliable Energy Economy, June 15 - 20, 2002, Reno, Nevada},
  booktitle = {Solar engineering 2002 : proceedings of the International Solar Energy Conference ; presented at the 2002 International Solar Energy Conference, a part of Solar 2002 - Sunrise on the Reliable Energy Economy, June 15 - 20, 2002, Reno, Nevada},
  editor    = {Pearson, J. Boise},
  publisher = {ASME},
  isbn      = {0-7918-1689-3},
  doi       = {doi:10.1115/SED2002-1072},
  pages     = {351 -- 359},
  year      = {2002},
  language  = {en}
}
@inproceedings{SattlerSchneiderAngeleetal.2022,
  author    = {Sattler, Johannes Christoph and Schneider, Iesse Peer and Angele, Florian and Atti, Vikrama Naga Babu and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Development of heliostat field calibration methods: Theory and experimental test results},
  series = {SolarPACES 2022 conference proceedings},
  booktitle = {SolarPACES 2022 conference proceedings},
  number    = {1},
  publisher = {TIB Open Publishing},
  address   = {Hannover},
  issn      = {2751-9899 (online)},
  doi       = {10.52825/solarpaces.v1i.678},
  pages     = {9 Seiten},
  year      = {2022},
  abstract  = {In this work, three patent pending calibration methods for heliostat fields of central receiver systems (CRS) developed by the Solar-Institut J{\"u}lich (SIJ) of the FH Aachen University of Applied Sciences are presented. The calibration methods can either operate in a combined mode or in stand-alone mode. The first calibration method, method A, foresees that a camera matrix is placed into the receiver plane where it is subjected to concentrated solar irradiance during a measurement process. The second calibration method, method B, uses an unmanned aerial vehicle (UAV) such as a quadrocopter to automatically fly into the reflected solar irradiance cross-section of one or more heliostats (two variants of method B were tested). The third calibration method, method C, foresees a stereo central camera or multiple stereo cameras installed e.g. on the solar tower whereby the orientations of the heliostats are calculated from the location detection of spherical red markers attached to the heliostats. The most accurate method is method A which has a mean accuracy of 0.17 mrad. The mean accuracy of method B variant 1 is 1.36 mrad and of variant 2 is 1.73 mrad. Method C has a mean accuracy of 15.07 mrad. For method B there is great potential regarding improving the measurement accuracy. For method C the collected data was not sufficient for determining whether or not there is potential for improving the accuracy.},
  language  = {en}
}
@inproceedings{ChicoCaminosSchmitzAttietal.2022,
  author    = {Chico Caminos, Ricardo Alexander and Schmitz, Pascal and Atti, Vikrama Naga Babu and Mahdi, Zahra and Teixeira Boura, Cristiano Jos{\´e} and Sattler, Johannes Christoph and Herrmann, Ulf and Hilger, Patrick and Dieckmann, Simon},
  title     = {Development of a micro heliostat and optical qualification assessment with a 3D laser scanning method},
  series = {SOLARPACES 2020},
  booktitle = {SOLARPACES 2020},
  number    = {2445 / 1},
  publisher = {AIP conference proceedings / American Institute of Physics},
  address   = {Melville, NY},
  isbn      = {978-0-7354-4195-8},
  issn      = {1551-7616 (online)},
  doi       = {10.1063/5.0086262},
  pages     = {8 Seiten},
  year      = {2022},
  abstract  = {The Solar-Institut J{\"u}lich (SIJ) and the companies Hilger GmbH and Heliokon GmbH from Germany have developed a small-scale cost-effective heliostat, called "micro heliostat". Micro heliostats can be deployed in small-scale concentrated solar power (CSP) plants to concentrate the sun's radiation for electricity generation, space or domestic water heating or industrial process heat. In contrast to conventional heliostats, the special feature of a micro heliostat is that it consists of dozens of parallel-moving, interconnected, rotatable mirror facets. The mirror facets array is fixed inside a box-shaped module and is protected from weathering and wind forces by a transparent glass cover. The choice of the building materials for the box, tracking mechanism and mirrors is largely dependent on the selected production process and the intended application of the micro heliostat. Special attention was paid to the material of the tracking mechanism as this has a direct influence on the accuracy of the micro heliostat. The choice of materials for the mirror support structure and the tracking mechanism is made in favor of plastic molded parts. A qualification assessment method has been developed by the SIJ in which a 3D laser scanner is used in combination with a coordinate measuring machine (CMM). For the validation of this assessment method, a single mirror facet was scanned and the slope deviation was computed.},
  language  = {en}
}
@inproceedings{MahdiRendonSchwageretal.2019,
  author    = {Mahdi, Zahra and Rend{\´o}n, Carlos and Schwager, Christian and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf},
  title     = {Novel concept for indirect solar-heated methane reforming},
  series = {AIP Conference Proceedings},
  volume    = {2126},
  booktitle = {AIP Conference Proceedings},
  publisher = {AIP Publishing},
  address   = {Melville, NY},
  issn      = {0094-243X},
  doi       = {10.1063/1.5117694},
  pages     = {180014-1 -- 180014-7},
  year      = {2019},
  language  = {en}
}
@article{MeyerHaenelBeehetal.2020,
  author    = {Meyer, S. and H{\"a}nel, Matthias and Beeh, B. and Dittmann-Gabriel, S{\"o}ren and Dluhosch, R. and May, Martin and Herrmann, Ulf},
  title     = {Multifunktionaler thermischer Stromspeicher f{\"u}r die Strom- und W{\"a}rmeversorgung der Industrie von morgen},
  series = {ETG Journal / Energietechnische Gesellschaft im VDE (ETG)},
  volume    = {2020},
  journal   = {ETG Journal / Energietechnische Gesellschaft im VDE (ETG)},
  number    = {1},
  issn      = {2625-9907},
  pages     = {6 -- 9},
  year      = {2020},
  language  = {de}
}
@article{HerrmannKearney2002,
  author    = {Herrmann, Ulf and Kearney, David W.},
  title     = {Survey of Thermal Energy Storage for Parabolic Trough Power Plants},
  series = {Journal of Solar Energy Engineering},
  volume    = {124},
  journal   = {Journal of Solar Energy Engineering},
  number    = {2},
  issn      = {1528-8986 (Online)},
  doi       = {10.1115/1.1467601},
  pages     = {145 -- 152},
  year      = {2002},
  language  = {en}
}
@article{KearneyKellyHerrmannetal.2002,
  author    = {Kearney, David W. and Kelly, Bruce and Herrmann, Ulf and Cable, R. and Pacheco, J. and Mahoney, R. and Price, Henry and Blake, D. and Nava, P. and Potrovitza, N.},
  title     = {Engineering Aspects of a Molten Salt Heat Transfer Fluid in a Trough Solar Field},
  series = {Energy : the international journal},
  volume    = {29},
  journal   = {Energy : the international journal},
  number    = {5-6 (Special Issue SolarPaces)},
  issn      = {0360-5442},
  doi       = {10.1016/S0360-5442(03)00191-9},
  pages     = {861 -- 870},
  year      = {2002},
  language  = {en}
}
@inproceedings{LuepfertHerrmannPriceetal.2004,
  author    = {L{\"u}pfert, E. and Herrmann, Ulf and Price, Henry and Zarza, E. and Kistener, R.},
  title     = {Towards Standard Performance Analysis for Parabolic Trough Collector Fields},
  series = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12},
  booktitle = {12th International Symposium Solar Power and Chemical Energy Systems, October 6-8, 2004, Oaxaca Mexico ; SolarPACES International Symposium, 12},
  editor    = {Ramos, C.},
  publisher = {Instituto de Investigaciones Electricas},
  address   = {[s.l.]},
  isbn      = {968-6114-18-1},
  year      = {2004},
  language  = {en}
}
@inproceedings{HerrmannVorbruggNava2009,
  author    = {Herrmann, Ulf and Vorbrugg, O. and Nava, P.},
  title     = {Construction and Commissioning Process of the Andasol Solar Field},
  series = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings},
  booktitle = {SolarPACES 2009 : electricity, fuels and clean water powered by the sun ; 15 - 18 September 2009, Berlin, Germany ; the 15th SolarPACES conference ; proceedings},
  publisher = {Deutsches Zentrum f{\"u}r Luft- u. Raumfahrt},
  address   = {Stuttgart},
  isbn      = {978-3-00-028755-8},
  pages     = {1 CD-ROM},
  year      = {2009},
  language  = {en}
}
@article{DammSauerbornFendetal.2017,
  author    = {Damm, Marc Andr{\´e} and Sauerborn, Markus and Fend, Thomas and Herrmann, Ulf},
  title     = {Optimisation of a urea selective catalytic reduction system with a coated ceramic mixing element},
  series = {Journal of ceramic science and technology},
  volume    = {8},
  journal   = {Journal of ceramic science and technology},
  number    = {1},
  publisher = {G{\"o}ller},
  address   = {Baden-Baden},
  isbn      = {2190-9385 (Print)},
  issn      = {2190-9385 (Online)},
  doi       = {10.4416/JCST2016-00056},
  pages     = {19 -- 24},
  year      = {2017},
  language  = {en}
}
@article{HerrmannLippke1999,
  author    = {Herrmann, Ulf and Lippke, F.},
  title     = {The influence of transients on the design of DSG solar fields},
  series = {Journal de Physique IV : proceedings},
  volume    = {9},
  journal   = {Journal de Physique IV : proceedings},
  number    = {PR3},
  isbn      = {2-86883-402-7},
  issn      = {1764-7177 (Online)},
  doi       = {10.1051/jp4:1999377},
  pages     = {489 -- 494},
  year      = {1999},
  language  = {en}
}
@article{HerrmannNava2005,
  author    = {Herrmann, Ulf and Nava, P.},
  title     = {Die Strahlung der Sonne einfangen},
  series = {DLR-Nachrichten / Deutsches Zentrum f{\"u}r Luft- und Raumfahrt},
  volume    = {109},
  journal   = {DLR-Nachrichten / Deutsches Zentrum f{\"u}r Luft- und Raumfahrt},
  number    = {Sonderheft Solarforschung},
  issn      = {0937-0420},
  pages     = {34 -- 37},
  year      = {2005},
  language  = {de}
}
@article{GoebelGeskesGeyeretal.1997,
  author    = {Goebel, O. and Geskes, P. and Geyer, Michael and Henneke, K. and Herrmann, Ulf},
  title     = {Direkte Dampferzeugung in Parabolrinnen-Solarkraftwerken},
  series = {Strom aus Sonne und Wind. - (Themen / Forschungsverbund Sonnenenergie ; 96/97)},
  journal   = {Strom aus Sonne und Wind. - (Themen / Forschungsverbund Sonnenenergie ; 96/97)},
  publisher = {Forschungsverb Sonnenenergie},
  address   = {K{\"o}ln},
  issn      = {0939-7582},
  pages     = {110 -- 116},
  year      = {1997},
  language  = {de}
}
@inproceedings{HerrmannRheinlaenderLippke1997,
  author    = {Herrmann, Ulf and Rheinl{\"a}nder, J. and Lippke, F.},
  title     = {Solar Fields for Direct Steam Generation in Parabolic Trough Collectors},
  series = {Components, tools, facilities and measurement techniques. - (Solar thermal concentrating technologies : proceedings of the 8th international symposium, October, 6 - 11, 1996, K{\"o}ln, Germany ; Vol. 2)},
  booktitle = {Components, tools, facilities and measurement techniques. - (Solar thermal concentrating technologies : proceedings of the 8th international symposium, October, 6 - 11, 1996, K{\"o}ln, Germany ; Vol. 2)},
  editor    = {Becker, Manfred},
  publisher = {M{\"u}ller},
  address   = {Heidelberg},
  isbn      = {3-7880-7616-X},
  pages     = {815 -- 834},
  year      = {1997},
  language  = {en}
}
@inproceedings{SattlerAttiAlexopoulosetal.2022,
  author    = {Sattler, Johannes Christoph and Atti, Vikrama Naga Babu and Alexopoulos, Spiros and Teixeira Boura, Cristiano Jos{\´e} and Herrmann, Ulf and Dutta, Siddharth and Kioutsioukis, Ioannis},
  title     = {DNI forecast tool for the smart operation of a parabolic trough collector system with concrete thermal energy storage: Theory, results and outlook},
  series = {SolarPACES 2022 conference proceedings},
  booktitle = {SolarPACES 2022 conference proceedings},
  number    = {1},
  publisher = {TIB Open Publishing},
  address   = {Hannover},
  issn      = {2751-9899 (online)},
  doi       = {10.52825/solarpaces.v1i.731},
  pages     = {9 Seiten},
  year      = {2022},
  abstract  = {This work presents a basic forecast tool for predicting direct normal irradiance (DNI) in hourly resolution, which the Solar-Institut J{\"u}lich (SIJ) is developing within a research project. The DNI forecast data shall be used for a parabolic trough collector (PTC) system with a concrete thermal energy storage (C-TES) located at the company KEAN Soft Drinks Ltd in Limassol, Cyprus. On a daily basis, 24-hour DNI prediction data in hourly resolution shall be automatically produced using free or very low-cost weather forecast data as input. The purpose of the DNI forecast tool is to automatically transfer the DNI forecast data on a daily basis to a main control unit (MCU). The MCU automatically makes a smart decision on the operation mode of the PTC system such as steam production mode and/or C-TES charging mode. The DNI forecast tool was evaluated using historical data of measured DNI from an on-site weather station, which was compared to the DNI forecast data. The DNI forecast tool was tested using data from 56 days between January and March 2022, which included days with a strong variation in DNI due to cloud passages. For the evaluation of the DNI forecast reliability, three categories were created and the forecast data was sorted accordingly. The result was that the DNI forecast tool has a reliability of 71.4 \% based on the tested days. The result fulfils SIJ's aim to achieve a reliability of around 70 \%, but SIJ aims to still improve the DNI forecast quality.},
  language  = {en}
}
@inproceedings{DuranParedesMottaghyHerrmannetal.2020,
  author    = {Duran Paredes, Ludwin and Mottaghy, Darius and Herrmann, Ulf and Groß, Rolf Fritz},
  title     = {Online ground temperature and soil moisture monitoring of a shallow geothermal system with non-conventional components},
  series = {EGU General Assembly 2020},
  booktitle = {EGU General Assembly 2020},
  year      = {2020},
  abstract  = {We present first results from a newly developed monitoring station for a closed loop geothermal heat pump test installation at our campus, consisting of helix coils and plate heat exchangers, as well as an ice-store system. There are more than 40 temperature sensors and several soil moisture content sensors distributed around the system, allowing a detailed monitoring under different operating conditions.In the view of the modern development of renewable energies along with the newly concepts known as Internet of Things and Industry 4.0 (high-tech strategy from the German government), we created a user-friendly web application, which will connect the things (sensors) with the open network (www). Besides other advantages, this allows a continuous remote monitoring of the data from the numerous sensors at an arbitrary sampling rate.Based on the recorded data, we will also present first results from numerical simulations, taking into account all relevant heat transport processes.The aim is to improve the understanding of these processes and their influence on the thermal behavior of shallow geothermal systems in the unsaturated zone. This will in turn facilitate the prediction of the performance of these systems and therefore yield an improvement in their dimensioning when designing a specific shallow geothermal installation.},
  language  = {en}
}