@inproceedings{HandschuhStollenwerkBorchert2021,
  author    = {Handschuh, Nils and Stollenwerk, Dominik and Borchert, J{\"o}rg},
  title     = {Operation of thermal storage power plants under high renewable grid penetration},
  series = {NEIS 2021: Conference on Sustainable Energy Supply and Energy Storage Systems},
  booktitle = {NEIS 2021: Conference on Sustainable Energy Supply and Energy Storage Systems},
  publisher = {VDE Verlag},
  address   = {Berlin},
  isbn      = {978-3-8007-5651-3},
  pages     = {261 -- 265},
  year      = {2021},
  abstract  = {The planned coal phase-out in Germany by 2038 will lead to the dismantling of power plants with a total capacity of approx. 30 GW. A possible further use of these assets is the conversion of the power plants to thermal storage power plants; the use of these power plants on the day-ahead market is considerably limited by their technical parameters. In this paper, the influence of the technical boundary conditions on the operating times of these storage facilities is presented. For this purpose, the storage power plants were described as an MILP problem and two price curves, one from 2015 with a relatively low renewable penetration (33 \%) and one from 2020 with a high renewable energy penetration (51 \%) are compared. The operating times were examined as a function of the technical parameters and the critical influencing factors were investigated. The thermal storage power plant operation duration and the energy shifted with the price curve of 2020 increases by more than 25 \% compared to 2015.},
  language  = {en}
}
@article{HoffstadtCheenakulaNikolauszetal.2023,
  author    = {Hoffstadt, Kevin and Cheenakula, Dheeraja and Nikolausz, Marcell and Krafft, Simone and Harms, Hauke and Kuperjans, Isabel},
  title     = {Design and construction of a new reactor for flexible biomethanation of hydrogen},
  series = {Fermentation},
  volume    = {9},
  journal   = {Fermentation},
  number    = {8},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2311-5637},
  doi       = {10.3390/fermentation9080774},
  pages     = {1 -- 16},
  year      = {2023},
  abstract  = {The increasing share of renewable electricity in the grid drives the need for sufficient storage capacity. Especially for seasonal storage, power-to-gas can be a promising approach. Biologically produced methane from hydrogen produced from surplus electricity can be used to substitute natural gas in the existing infrastructure. Current reactor types are not or are poorly optimized for flexible methanation. Therefore, this work proposes a new reactor type with a plug flow reactor (PFR) design. Simulations in COMSOL Multiphysics ® showed promising properties for operation in laminar flow. An experiment was conducted to support the simulation results and to determine the gas fraction of the novel reactor, which was measured to be 29\%. Based on these simulations and experimental results, the reactor was constructed as a 14 m long, 50 mm diameter tube with a meandering orientation. Data processing was established, and a step experiment was performed. In addition, a kLa of 1 h-1 was determined. The results revealed that the experimental outcomes of the type of flow and gas fractions are in line with the theoretical simulation. The new design shows promising properties for flexible methanation and will be tested.},
  language  = {en}
}
@article{HoffstadtPohenDickeetal.2020,
  author    = {Hoffstadt, Kevin and Pohen, Gino D. and Dicke, Max D. and Paulsen, Svea and Krafft, Simone and Zang, Joachim W. and Fonseca-Zang, Warde A. da and Leite, Athaydes and Kuperjans, Isabel},
  title     = {Challenges and prospects of biogas from energy cane as supplement to bioethanol production},
  series = {Agronomy},
  volume    = {10},
  journal   = {Agronomy},
  number    = {6},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2073-4395},
  doi       = {10.3390/agronomy10060821},
  year      = {2020},
  abstract  = {Innovative breeds of sugar cane yield up to 2.5 times as much organic matter as conventional breeds, resulting in a great potential for biogas production. The use of biogas production as a complementary solution to conventional and second-generation ethanol production in Brazil may increase the energy produced per hectare in the sugarcane sector. Herein, it was demonstrated that through ensiling, energy cane can be conserved for six months; the stored cane can then be fed into a continuous biogas process. This approach is necessary to achieve year-round biogas production at an industrial scale. Batch tests revealed specific biogas potentials between 400 and 600 LN/kgVS for both the ensiled and non-ensiled energy cane, and the specific biogas potential of a continuous biogas process fed with ensiled energy cane was in the same range. Peak biogas losses through ensiling of up to 27\% after six months were observed. Finally, compared with second-generation ethanol production using energy cane, the results indicated that biogas production from energy cane may lead to higher energy yields per hectare, with an average energy yield of up to 162 MWh/ha. Finally, the Farm²CBG concept is introduced, showing an approach for decentralized biogas production.},
  language  = {en}
}
@article{JablonowskiKollmannNabeletal.2016,
  author    = {Jablonowski, Nicolai David and Kollmann, Tobias and Nabel, Moritz and Damm, Tatjana and Klose, Holger and M{\"u}ller, Michael and Bl{\"a}sing, Marc and Seebold, S{\"o}ren and Krafft, Simone and Kuperjans, Isabel and Dahmen, Markus and Schurr, Ulrich},
  title     = {Valorization of Sida (Sida hermaphrodita) biomass for multiple energy purposes},
  series = {GCB [Global Change Biology] Bioenergy},
  volume    = {9},
  journal   = {GCB [Global Change Biology] Bioenergy},
  number    = {1},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1757-1707 (online)},
  doi       = {10.1111/gcbb.12346},
  pages     = {202 -- 214},
  year      = {2016},
  abstract  = {The performance and biomass yield of the perennial energy plant Sida hermaphrodita (hereafter referred to as Sida) as a feedstock for biogas and solid fuel was evaluated throughout one entire growing period at agricultural field conditions. A Sida plant development code was established to allow comparison of the plant growth stages and biomass composition. Four scenarios were evaluated to determine the use of Sida biomass with regard to plant development and harvest time: (i) one harvest for solid fuel only; (ii) one harvest for biogas production only; (iii) one harvest for biogas production, followed by a harvest of the regrown biomass for solid fuel; and (iv) two consecutive harvests for biogas production. To determine Sida's value as a feedstock for combustion, we assessed the caloric value, the ash quality, and melting point with regard to DIN EN ISO norms. The results showed highest total dry biomass yields of max. 25 t ha⁻¹, whereas the highest dry matter of 70\% to 80\% was obtained at the end of the growing period. Scenario (i) clearly indicated the highest energy recovery, accounting for 439 288 MJ ha⁻¹; the energy recovery of the four scenarios from highest to lowest followed this order: (i) ≫ (iii) ≫ (iv) > (ii). Analysis of the Sida ashes showed a high melting point of >1500 °C, associated with a net calorific value of 16.5-17.2 MJ kg⁻¹. All prerequisites for DIN EN ISO norms were achieved, indicating Sida's advantage as a solid energy carrier without any post-treatment after harvesting. Cell wall analysis of the stems showed a constant lignin content after sampling week 16 (July), whereas cellulose had already reached a plateau in sampling week 4 (April). The results highlight Sida as a promising woody, perennial plant, providing biomass for flexible and multipurpose energy applications.},
  language  = {en}
}
@incollection{JordanKatzPieper2021,
  author    = {Jordan, Frank and Katz, Christiane and Pieper, Martin},
  title     = {Online-Kollaboration in der Mathematik: Ein Design-Based-Research-Projekt},
  series = {Forschungsimpulse f{\"u}r hybrides Lehren und Lernen an Hochschulen},
  booktitle = {Forschungsimpulse f{\"u}r hybrides Lehren und Lernen an Hochschulen},
  publisher = {TH K{\"o}ln},
  address   = {K{\"o}ln},
  url       = {http://nbn-resolving.de/urn:nbn:de:hbz:832-cos4-9465},
  pages     = {245 -- 261},
  year      = {2021},
  abstract  = {Die Studie er{\"o}rtert anhand eines Fallbeispiels aus der Mathematik f{\"u}r Ingenieur*innen, wie didaktische Gestaltungsprinzipien f{\"u}r Soziale Pr{\"a}senz, Kollaboration und das L{\"o}sen von praxisnahen Problemen mit mathematischem Denken in einer Online-Umgebung aussehen k{\"o}nnen. Hierf{\"u}r zieht der Beitrag den forschungsmethodologischen Rahmen Design-Based Research (DBR) hinzu und berichtet {\"u}ber Zwischenergebnisse. DBR wird an dieser Stelle als eine systematische Herangehensweise an kurzfristige Lehrver{\"a}nderungen und als Chance auf dem Weg zu einer neuen Hochschullehre nach der COVID-19-Pandemie dargestellt, die theoretische und empirische Erkenntnisse mit Praxisverkn{\"u}pfung und -relevanz vereint.},
  language  = {de}
}
@inproceedings{KasparGroebelKuperjansetal.2013,
  author    = {Kaspar, K. and Groebel, Simone and Kuperjans, Isabel and Dielmann, Klaus-Peter and Selmer, Thorsten},
  title     = {Charakterisierung der Bioz{\"o}nose von Biogasfermentern in Abh{\"a}ngigkeit verschiedener Substrate},
  series = {Biogas 2013 : 6. Innovationskongress, 23. - 24.05.2013, Osnabr{\"u}ck, Tagungsband},
  booktitle = {Biogas 2013 : 6. Innovationskongress, 23. - 24.05.2013, Osnabr{\"u}ck, Tagungsband},
  publisher = {Profair Consult+Project},
  address   = {Hildesheim},
  issn      = {978-3-9813776-3-7},
  pages     = {69 -- 74},
  year      = {2013},
  language  = {de}
}
@inproceedings{KasperSchiffelsKrafftetal.2016,
  author    = {Kasper, Katharina and Schiffels, Johannes and Krafft, Simone and Kuperjans, Isabel and Elbers, Gereon and Selmer, Thorsten},
  title     = {Biogas Production on Demand Regulated by Butyric Acid Addition},
  series = {IOP Conference Series: Earth and Environmental Science. Bd. 32},
  volume    = {32},
  booktitle = {IOP Conference Series: Earth and Environmental Science. Bd. 32},
  issn      = {1755-1315},
  doi       = {10.1088/1755-1315/32/1/012009},
  pages     = {012009/1 -- 012009/4},
  year      = {2016},
  language  = {en}
}
@incollection{KnocheKruskaWeberetal.2001,
  author    = {Knoche, K. F. and Kruska, Martin and Weber, P. and Kuperjans, Isabel},
  title     = {Energiemanagement},
  series = {Lexikon Nachhaltiges Wirtschaften. - (Lehr- und Handb{\"u}cher zur {\"o}kologischen Unternehmensf{\"u}hrung und Umwelt{\"o}konomie)},
  booktitle = {Lexikon Nachhaltiges Wirtschaften. - (Lehr- und Handb{\"u}cher zur {\"o}kologischen Unternehmensf{\"u}hrung und Umwelt{\"o}konomie)},
  editor    = {Schulz, Werner F.},
  publisher = {Oldenbourg},
  address   = {M{\"u}nchen [u.a.]},
  isbn      = {3-486-24523-6},
  pages     = {88 -- 92},
  year      = {2001},
  language  = {de}
}
@inproceedings{KreyerEsch2017,
  author    = {Kreyer, J{\"o}rg and Esch, Thomas},
  title     = {Simulation Tool for Predictive Control Strategies for an ORCSystem in Heavy Duty Vehicles},
  series = {European GT Conference 2017},
  booktitle = {European GT Conference 2017},
  pages     = {16 Seiten},
  year      = {2017},
  abstract  = {Scientific questions - How can a non-stationary heat offering in the commercial vehicle be used to reduce fuel consumption? - Which potentials offer route and environmental information among with predicted speed and load trajectories to increase the efficiency of a ORC-System? Methods - Desktop bound holistic simulation model for a heavy duty truck incl. an ORC System - Prediction of massflows, temperatures and mixture quality (AFR) of exhaust gas},
  language  = {en}
}
@incollection{KruskaKuperjans1999,
  author    = {Kruska, Martin and Kuperjans, Isabel},
  title     = {An{\´a}lisis Thermodin{\´a}micos : [Cap{\´i}tulo 3.3]},
  series = {Uso racional de energ{\´i}a : eficiencia energ{\´e}tica y energ{\´i}as renovables. - (Manual para consultores y expertos)},
  booktitle = {Uso racional de energ{\´i}a : eficiencia energ{\´e}tica y energ{\´i}as renovables. - (Manual para consultores y expertos)},
  publisher = {Ministerio de Energ{\´i}a y Minas},
  address   = {Lima},
  pages     = {3.3-1 -- 3.3-15},
  year      = {1999},
  language  = {es}
}