@article{RuppRiekeHandschuhetal.2020,
  author    = {Rupp, Matthias and Rieke, Christian and Handschuh, Nils and Kuperjans, Isabel},
  title     = {Economic and ecological optimization of electric bus charging considering variable electricity prices and CO₂eq intensities},
  series = {Transportation Research Part D: Transport and Environment},
  volume    = {81},
  journal   = {Transportation Research Part D: Transport and Environment},
  number    = {Article 102293},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1361-9209},
  doi       = {10.1016/j.trd.2020.102293},
  year      = {2020},
  abstract  = {In many cities, diesel buses are being replaced by electric buses with the aim of reducing local emissions and thus improving air quality. The protection of the environment and the health of the population is the highest priority of our society. For the transport companies that operate these buses, not only ecological issues but also economic issues are of great importance. Due to the high purchase costs of electric buses compared to conventional buses, operators are forced to use electric vehicles in a targeted manner in order to ensure amortization over the service life of the vehicles. A compromise between ecology and economy must be found in order to both protect the environment and ensure economical operation of the buses. In this study, we present a new methodology for optimizing the vehicles' charging time as a function of the parameters CO₂eq emissions and electricity costs. Based on recorded driving profiles in daily bus operation, the energy demands of conventional and electric buses are calculated for the passenger transportation in the city of Aachen in 2017. Different charging scenarios are defined to analyze the influence of the temporal variability of CO₂eq intensity and electricity price on the environmental impact and economy of the bus. For every individual day of a year, charging periods with the lowest and highest costs and emissions are identified and recommendations for daily bus operation are made. To enable both the ecological and economical operation of the bus, the parameters of electricity price and CO₂ are weighted differently, and several charging periods are proposed, taking into account the priorities previously set. A sensitivity analysis is carried out to evaluate the influence of selected parameters and to derive recommendations for improving the ecological and economic balance of the battery-powered electric vehicle. In all scenarios, the optimization of the charging period results in energy cost savings of a maximum of 13.6\% compared to charging at a fixed electricity price. The savings potential of CO₂eq emissions is similar, at 14.9\%. From an economic point of view, charging between 2 a.m. and 4 a.m. results in the lowest energy costs on average. The CO₂eq intensity is also low in this period, but midday charging leads to the largest savings in CO₂eq emissions. From a life cycle perspective, the electric bus is not economically competitive with the conventional bus. However, from an ecological point of view, the electric bus saves on average 37.5\% CO₂eq emissions over its service life compared to the diesel bus. The reduction potential is maximized if the electric vehicle exclusively consumes electricity from solar and wind power.},
  language  = {en}
}
@article{DotzauerPfeifferLaueretal.2019,
  author    = {Dotzauer, Martin and Pfeiffer, Diana and Lauer, Markus and Pohl, Marcel and Mauky, Eric and B{\"a}r, Katharina and Sonnleitner, Matthias and Z{\"o}rner, Wilfried and Hudde, Jessica and Schwarz, Bj{\"o}rn and Faßauer, Burkhardt and Dahmen, Markus and Rieke, Christian and Herbert, Johannes and Thr{\"a}n, Daniela},
  title     = {How to measure flexibility - Performance indicators for demand driven power generation from biogas plants},
  series = {Renewable Energy},
  journal   = {Renewable Energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0960-1481},
  doi       = {10.1016/j.renene.2018.10.021},
  pages     = {135 -- 146},
  year      = {2019},
  language  = {en}
}
@article{RuppHandschuhRiekeetal.2019,
  author    = {Rupp, Matthias and Handschuh, Nils and Rieke, Christian and Kuperjans, Isabel},
  title     = {Contribution of country-specific electricity mix and charging time to environmental impact of battery electric vehicles: A case study of electric buses in Germany},
  series = {Applied Energy},
  volume    = {237},
  journal   = {Applied Energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0306-2619},
  doi       = {10.1016/j.apenergy.2019.01.059},
  pages     = {618 -- 634},
  year      = {2019},
  language  = {en}
}
@article{RuppSchulzeKuperjans2018,
  author    = {Rupp, Matthias and Schulze, Sven and Kuperjans, Isabel},
  title     = {Comparative life cycle analysis of conventional and hybrid heavy-duty trucks},
  series = {World electric vehicle journal},
  volume    = {9},
  journal   = {World electric vehicle journal},
  number    = {2},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2032-6653},
  doi       = {10.3390/wevj9020033},
  pages     = {Article No. 33},
  year      = {2018},
  abstract  = {Heavy-duty trucks are one of the main contributors to greenhouse gas emissions in German traffic. Drivetrain electrification is an option to reduce tailpipe emissions by increasing energy conversion efficiency. To evaluate the vehicle's environmental impacts, it is necessary to consider the entire life cycle. In addition to the daily use, it is also necessary to include the impact of production and disposal. This study presents the comparative life cycle analysis of a parallel hybrid and a conventional heavy-duty truck in long-haul operation. Assuming a uniform vehicle glider, only the differing parts of both drivetrains are taken into account to calculate the environmental burdens of the production. The use phase is modeled by a backward simulation in MATLAB/Simulink considering a characteristic driving cycle. A break-even analysis is conducted to show at what mileage the larger CO2eq emissions due to the production of the electric drivetrain are compensated. The effect of parameter variation on the break-even mileage is investigated by a sensitivity analysis. The results of this analysis show the difference in CO2eq/t km is negative, indicating that the hybrid vehicle releases 4.34 g CO2eq/t km over a lifetime fewer emissions compared to the diesel truck. The break-even analysis also emphasizes the advantages of the electrified drivetrain, compensating the larger emissions generated during production after already a distance of 15,800 km (approx. 1.5 months of operation time). The intersection coordinates, distance, and CO2eq, strongly depend on fuel, emissions for battery production and the driving profile, which lead to nearly all parameter variations showing an increase in break-even distance.},
  language  = {en}
}
@article{RiekeStollenwerkDahmenetal.2018,
  author    = {Rieke, Christian and Stollenwerk, Dominik and Dahmen, Markus and Pieper, Martin},
  title     = {Modeling and optimization of a biogas plant for a demand-driven energy supply},
  series = {Energy},
  volume    = {145},
  journal   = {Energy},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0360-5442},
  doi       = {10.1016/j.energy.2017.12.073},
  pages     = {657 -- 664},
  year      = {2018},
  abstract  = {Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60\%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process. This paper provides a new model of a biogas plant, which is as accurate as the standard ADM1 model. The advantage compared to ADM1 is that it is based on only four parameters compared to 28. Applying this model, an optimization was installed, which allows a demand-driven supply by biogas plants. Finally the results are confirmed by several experiments and measurements with a real test plant.},
  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}
}
@article{KuperjansWeitzel2015,
  author    = {Kuperjans, Isabel and Weitzel, J.},
  title     = {Energiedesign 2020 : Sichere Strom- und W{\"a}rmeversorgung f{\"u}r die Industrie},
  series = {TAB: das Fachmedium der TGA-Branche},
  journal   = {TAB: das Fachmedium der TGA-Branche},
  number    = {3},
  publisher = {Bauverlag},
  address   = {G{\"u}tersloh},
  issn      = {0341-2032},
  pages     = {105 -- 107},
  year      = {2015},
  language  = {de}
}
@article{Kuperjans1996,
  author    = {Kuperjans, Isabel},
  title     = {Exergetische und exergo{\"o}konomische Analyse thermischer Prozesse},
  series = {Arbeitsbericht / Institut f{\"u}r Wirtschaftswissenschaften, Rheinisch-Westf{\"a}lische Technische Hochschule Aachen},
  journal   = {Arbeitsbericht / Institut f{\"u}r Wirtschaftswissenschaften, Rheinisch-Westf{\"a}lische Technische Hochschule Aachen},
  number    = {06},
  year      = {1996},
  language  = {de}
}
@article{KuperjansEsserMeyeretal.2000,
  author    = {Kuperjans, Isabel and Esser, J. and Meyer, J{\"o}rg and Donner, O.},
  title     = {Gestaltung und Bewertung von Energieanlagen unter {\"o}kologischen, wirtschaftlichen und technischen Gesichtspunkten},
  series = {Umweltwirtschaftsforum : UWF},
  volume    = {8},
  journal   = {Umweltwirtschaftsforum : UWF},
  number    = {3},
  issn      = {0943-3481},
  pages     = {53 -- 58},
  year      = {2000},
  language  = {de}
}
@article{KuperjansStarkeEsseretal.2000,
  author    = {Kuperjans, Isabel and Starke, M. and Esser, J. and [u.a.],},
  title     = {Analyse und Konzeption von Energieanlagen unter {\"o}kologischen, wirtschaftlichen und technischen Gesichtspunkten},
  series = {WLB : Umwelttechnik f{\"u}r Industrie und Kommune},
  volume    = {44},
  journal   = {WLB : Umwelttechnik f{\"u}r Industrie und Kommune},
  number    = {11/12},
  issn      = {0341-2679},
  pages     = {26 -- 29},
  year      = {2000},
  language  = {de}
}
@article{PauksztatKuperjansMeyer2005,
  author    = {Pauksztat, Anja and Kuperjans, Isabel and Meyer, J{\"o}rg},
  title     = {Produktbezogene Referenzwerte f{\"u}r Energieeffizienz und CO2-Emissionen},
  series = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  volume    = {55},
  journal   = {Energiewirtschaftliche Tagesfragen : et ; Zeitschrift f{\"u}r Energiewirtschaft, Recht, Technik und Umwelt},
  number    = {6},
  issn      = {0013-743X},
  pages     = {374 -- 376},
  year      = {2005},
  language  = {de}
}
@article{KuperjansGuerzenichRoosen2005,
  author    = {Kuperjans, Isabel and G{\"u}rzenich, D. and Roosen, P.},
  title     = {Kostenfunktionen im WWW : Unterst{\"u}tzung der Auslegung energietechnischer Anlagen und deren Verschaltungen},
  series = {Gasw{\"a}rme international (GWI)},
  volume    = {54},
  journal   = {Gasw{\"a}rme international (GWI)},
  number    = {1},
  issn      = {0020-9384},
  pages     = {19 -- 21},
  year      = {2005},
  language  = {de}
}
@article{PauksztatKuperjansMeyer2005,
  author    = {Pauksztat, Anja and Kuperjans, Isabel and Meyer, J{\"o}rg},
  title     = {Formeln statt Zahlen : Referenzwerte Formeln zur energetischen Bewertung von Produktionsanlagen},
  series = {BWK : das Energie-Fachmagazin},
  volume    = {57},
  journal   = {BWK : das Energie-Fachmagazin},
  number    = {12},
  issn      = {0006-9612},
  pages     = {52 -- 55},
  year      = {2005},
  language  = {de}
}
@article{AugensteinHerbergsKuperjans2006,
  author    = {Augenstein, Eckardt and Herbergs, S. and Kuperjans, Isabel},
  title     = {TOP-Energy : ein Werkzeug zur Optimierung der Geb{\"a}udeenergieversorgung},
  series = {KI : K{\"a}lte, Luft, Klimatechnik},
  journal   = {KI : K{\"a}lte, Luft, Klimatechnik},
  number    = {5},
  issn      = {1865-5432},
  pages     = {198 -- 201},
  year      = {2006},
  language  = {de}
}
@article{Kuperjans2011,
  author    = {Kuperjans, Isabel},
  title     = {Gute Planung ist alles : Energieeffizienz in der Pharmaproduktion},
  series = {Pharma + Food},
  volume    = {2011},
  journal   = {Pharma + Food},
  number    = {2},
  publisher = {H{\"u}thig},
  address   = {Heidelberg},
  issn      = {1434-8942},
  pages     = {8 -- 10},
  year      = {2011},
  language  = {de}
}
@article{WernerGroebelKrumbeetal.2012,
  author    = {Werner, Frederik and Groebel, Simone and Krumbe, Christoph and Wagner, Torsten and Selmer, Thorsten and Yoshinobu, Tatsuo and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {Nutrient concentration-sensitive microorganism-based biosensor},
  series = {Physica Status Solidi (a)},
  volume    = {209},
  journal   = {Physica Status Solidi (a)},
  number    = {5},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1862-6319},
  doi       = {10.1002/pssa.201100801},
  pages     = {900 -- 904},
  year      = {2012},
  language  = {en}
}
@article{WernerGroebelWagneretal.2011,
  author    = {Werner, Frederik and Groebel, Simone and Wagner, Torsten and Yoshinobu, Tatsuo and Selmer, Thorsten and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {{\"U}berwachung der metabolischen Aktivit{\"a}t von Mikroorganismen zur Kontrolle des biologischen Prozesses im Biogasfermenter},
  series = {Biogas 2011 : Energietr{\"a}ger der Zukunft ; 6. Fachtagung, Fachtagung Braunschweig, 08. und 09. Juni 2011 / VDI Energie und Umwelt},
  journal   = {Biogas 2011 : Energietr{\"a}ger der Zukunft ; 6. Fachtagung, Fachtagung Braunschweig, 08. und 09. Juni 2011 / VDI Energie und Umwelt},
  publisher = {VDI-Verl.},
  address   = {D{\"u}sseldorf},
  isbn      = {978-3-18-092121-1},
  pages     = {285 -- 286},
  year      = {2011},
  language  = {de}
}
@article{WernerKrumbeSchumacheretal.2011,
  author    = {Werner, Frederik and Krumbe, Christoph and Schumacher, Katharina and Groebel, Simone and Spelthahn, Heiko and Stellberg, Michael and Wagner, Torsten and Yoshinobu, Tatsuo and Selmer, Thorsten and Keusgen, Michael and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {Determination of the extracellular acidification of Escherichia coli by a light-addressable potentiometric sensor},
  series = {Physica status solidi (a) : applications and material science. 208 (2011), H. 6},
  journal   = {Physica status solidi (a) : applications and material science. 208 (2011), H. 6},
  publisher = {Wiley},
  address   = {Weinheim},
  isbn      = {1862-6319},
  pages     = {1340 -- 1344},
  year      = {2011},
  language  = {en}
}
@article{WernerGroebelSchuhmacheretal.2009,
  author    = {Werner, Frederik and Groebel, Simone and Schuhmacher, K. and Spelthahn, Heiko and Wagner, Torsten and Selmer, Thorsten and Baumann, Marcus and Sch{\"o}ning, Michael Josef},
  title     = {Bestimmung der metabolischen Aktivit{\"a}t von Mikroorganismen w{\"a}hrend des Biogasbildungsprozesses},
  series = {9. Dresdner Sensor-Symposium : Dresden, 07.-09. Dezember 2009 / Gerlach, Gerald ; Hauptmann, Peter [Hrsg.]},
  journal   = {9. Dresdner Sensor-Symposium : Dresden, 07.-09. Dezember 2009 / Gerlach, Gerald ; Hauptmann, Peter [Hrsg.]},
  publisher = {TUDpress},
  address   = {Dresden},
  isbn      = {978-3-941298-44-6},
  pages     = {201 -- 204},
  year      = {2009},
  language  = {de}
}
@article{DielmannBockSonnek2007,
  author    = {Dielmann, Klaus-Peter and Bock, Alexis and Sonnek, Frederic},
  title     = {Stand der CO2-Allokationspl{\"a}ne in Europa und Durchsetzung der Monitoring-Richtlinien},
  series = {VGB PowerTech : international journal for electricity and heat generation},
  volume    = {87},
  journal   = {VGB PowerTech : international journal for electricity and heat generation},
  number    = {3},
  isbn      = {1435-3199},
  pages     = {40 -- 46},
  year      = {2007},
  language  = {de}
}
@article{DielmannCudinaMehlkopf2003,
  author    = {Dielmann, Klaus-Peter and Cudina, Boris and Mehlkopf, Marcus},
  title     = {Einfluss der Brennstoffdaten auf die CO2-Inventarisierung : Handel mit Emissionsrechten},
  series = {Euroheat and power : Kraft-W{\"a}rme-Kopplung, Nah-/Fernw{\"a}rme, Contracting},
  volume    = {32},
  journal   = {Euroheat and power : Kraft-W{\"a}rme-Kopplung, Nah-/Fernw{\"a}rme, Contracting},
  number    = {9},
  isbn      = {0949-166X},
  pages     = {22 -- 25},
  year      = {2003},
  language  = {de}
}
@article{DielmannMehlkopf2005,
  author    = {Dielmann, Klaus-Peter and Mehlkopf, Marcus},
  title     = {National zugeteilte Emissionen},
  series = {BWK : das Energie-Fachmagazin},
  volume    = {57},
  journal   = {BWK : das Energie-Fachmagazin},
  number    = {5},
  isbn      = {0006-9612},
  issn      = {1618-193X},
  pages     = {48 -- 52},
  year      = {2005},
  language  = {de}
}
@article{DielmannMehlkopfCudina2005,
  author    = {Dielmann, Klaus-Peter and Mehlkopf, Marcus and Cudina, Boris},
  title     = {Der Handel mit Emissionsrechten : Vorbereitung auf den europaweiten Start 2005},
  series = {VGB PowerTech : international journal for electricity and heat generation},
  volume    = {85},
  journal   = {VGB PowerTech : international journal for electricity and heat generation},
  number    = {1/2},
  isbn      = {1435-3199},
  pages     = {66 -- 69},
  year      = {2005},
  language  = {de}
}
@article{DielmannMehlkopfCudina2004,
  author    = {Dielmann, Klaus-Peter and Mehlkopf, Marcus and Cudina, Boris},
  title     = {Erfahrungen mit der Software Risa-Gen},
  series = {BWK : das Energie-Fachmagazin},
  volume    = {56},
  journal   = {BWK : das Energie-Fachmagazin},
  number    = {3},
  isbn      = {0006-9612},
  issn      = {1618-193X},
  pages     = {24 -- 25},
  year      = {2004},
  language  = {de}
}