@inproceedings{BlankeSchmidtGoettscheetal.2022,
  author    = {Blanke, Tobias and Schmidt, Katharina S. and G{\"o}ttsche, Joachim and D{\"o}ring, Bernd and Frisch, J{\´e}r{\^o}me and van Treeck, Christoph},
  title     = {Time series aggregation for energy system design: review and extension of modelling seasonal storages},
  series = {Energy Informatics},
  volume    = {5},
  booktitle = {Energy Informatics},
  number    = {1, Article number: 17},
  editor    = {Weidlich, Anke and Neumann, Dirk and Gust, Gunther and Staudt, Philipp and Sch{\"a}fer, Mirko},
  publisher = {Springer Nature},
  issn      = {2520-8942},
  doi       = {10.1186/s42162-022-00208-5},
  pages     = {1 -- 14},
  year      = {2022},
  abstract  = {Using optimization to design a renewable energy system has become a computationally demanding task as the high temporal fluctuations of demand and supply arise within the considered time series. The aggregation of typical operation periods has become a popular method to reduce effort. These operation periods are modelled independently and cannot interact in most cases. Consequently, seasonal storage is not reproducible. This inability can lead to a significant error, especially for energy systems with a high share of fluctuating renewable energy. The previous paper, "Time series aggregation for energy system design: Modeling seasonal storage", has developed a seasonal storage model to address this issue. Simultaneously, the paper "Optimal design of multi-energy systems with seasonal storage" has developed a different approach. This paper aims to review these models and extend the first model. The extension is a mathematical reformulation to decrease the number of variables and constraints. Furthermore, it aims to reduce the calculation time while achieving the same results.},
  language  = {en}
}
@article{BlankeHagenkampDoeringetal.2021,
  author    = {Blanke, Tobias and Hagenkamp, Markus and D{\"o}ring, Bernd and G{\"o}ttsche, Joachim and Reger, Vitali and Kuhnhenne, Markus},
  title     = {Net-exergetic, hydraulic and thermal optimization of coaxial heat exchangers using fixed flow conditions instead of fixed flow rates},
  series = {Geothermal Energy},
  volume    = {9},
  journal   = {Geothermal Energy},
  number    = {Article number: 19},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {2195-9706},
  doi       = {10.1186/s40517-021-00201-3},
  pages     = {23 Seiten},
  year      = {2021},
  abstract  = {Previous studies optimized the dimensions of coaxial heat exchangers using constant mass fow rates as a boundary condition. They show a thermal optimal circular ring width of nearly zero. Hydraulically optimal is an inner to outer pipe radius ratio of 0.65 for turbulent and 0.68 for laminar fow types. In contrast, in this study, fow conditions in the circular ring are kept constant (a set of fxed Reynolds numbers) during optimization. This approach ensures fxed fow conditions and prevents inappropriately high or low mass fow rates. The optimization is carried out for three objectives: Maximum energy gain, minimum hydraulic efort and eventually optimum net-exergy balance. The optimization changes the inner pipe radius and mass fow rate but not the Reynolds number of the circular ring. The thermal calculations base on Hellstr{\"o}m's borehole resistance and the hydraulic optimization on individually calculated linear loss of head coefcients. Increasing the inner pipe radius results in decreased hydraulic losses in the inner pipe but increased losses in the circular ring. The net-exergy diference is a key performance indicator and combines thermal and hydraulic calculations. It is the difference between thermal exergy fux and hydraulic efort. The Reynolds number in the circular ring is instead of the mass fow rate constant during all optimizations. The result from a thermal perspective is an optimal width of the circular ring of nearly zero. The hydraulically optimal inner pipe radius is 54\% of the outer pipe radius for laminar fow and 60\% for turbulent fow scenarios. Net-exergetic optimization shows a predominant infuence of hydraulic losses, especially for small temperature gains. The exact result depends on the earth's thermal properties and the fow type. Conclusively, coaxial geothermal probes' design should focus on the hydraulic optimum and take the thermal optimum as a secondary criterion due to the dominating hydraulics.},
  language  = {en}
}
@article{HagenkampBlankeDoering2021,
  author    = {Hagenkamp, Markus and Blanke, Tobias and D{\"o}ring, Bernd},
  title     = {Thermoelectric building temperature control: a potential assessment},
  series = {International Journal of Energy and Environmental Engineering},
  volume    = {13},
  journal   = {International Journal of Energy and Environmental Engineering},
  publisher = {Springer},
  address   = {Berlin},
  doi       = {10.1007/s40095-021-00424-x},
  pages     = {241 -- 254},
  year      = {2021},
  abstract  = {This study focuses on thermoelectric elements (TEE) as an alternative for room temperature control. TEE are semi-conductor devices that can provide heating and cooling via a heat pump effect without direct noise emissions and no refrigerant use. An efficiency evaluation of the optimal operating mode is carried out for different numbers of TEE, ambient temperatures, and heating loads. The influence of an additional heat recovery unit on system efficiency and an unevenly distributed heating demand are examined. The results show that TEE can provide heat at a coefficient of performance (COP) greater than one especially for small heating demands and high ambient temperatures. The efficiency increases with the number of elements in the system and is subject to economies of scale. The best COP exceeds six at optimal operating conditions. An additional heat recovery unit proves beneficial for low ambient temperatures and systems with few TEE. It makes COPs above one possible at ambient temperatures below 0 ∘C. The effect increases efficiency by maximal 0.81 (from 1.90 to 2.71) at ambient temperature 5 K below room temperature and heating demand Q˙h=100W but is subject to diseconomies of scale. Thermoelectric technology is a valuable option for electricity-based heat supply and can provide cooling and ventilation functions. A careful system design as well as an additional heat recovery unit significantly benefits the performance. This makes TEE superior to direct current heating systems and competitive to heat pumps for small scale applications with focus on avoiding noise and harmful refrigerants.},
  language  = {en}
}
@article{KuhnhenneRegerPyschnyetal.2020,
  author    = {Kuhnhenne, Markus and Reger, Vitali and Pyschny, Dominik and D{\"o}ring, Bernd},
  title     = {Influence of airtightness of steel sandwich panel joints on heat losses},
  series = {E3S Web of Conferences 12th Nordic Symposium on Building Physics (NSB 2020)},
  volume    = {172},
  journal   = {E3S Web of Conferences 12th Nordic Symposium on Building Physics (NSB 2020)},
  number    = {Art. 05008},
  publisher = {EDP Sciences},
  address   = {Les Ulis},
  doi       = {10.1051/e3sconf/202017205008},
  pages     = {6},
  year      = {2020},
  abstract  = {Energy saving ordinances requires that buildings must be designed in such a way that the heat transfer surface including the joints is permanently air impermeable. The prefabricated roof and wall panels in lightweight steel constructions are airtight in the area of the steel covering layers. The sealing of the panel joints contributes to fulfil the comprehensive requirements for an airtight building envelope. To improve the airtightness of steel sandwich panels, additional sealing tapes can be installed in the panel joint. The influence of these sealing tapes was evaluated by measurements carried out by the RWTH Aachen University - Sustainable Metal Building Envelopes. Different installation situations were evaluated by carrying out airtightness tests for different joint distances. In addition, the influence on the heat transfer coefficient was also evaluated using the Finite Element Method (FEM). The combination of obtained air volume flow and transmission losses enables to create an "effective heat transfer coefficient" due to transmission and infiltration. This summarizes both effects in one value and is particularly helpful for approximate calculations on energy efficiency.},
  language  = {en}
}
@techreport{SansomLawsonTuchoetal.2016,
  author    = {Sansom, M. and Lawson, R.M. and Tucho, R. and Kendrick, C. and Ogden, R. and Resalati, S. and Garay, R. and D{\"o}ring, Bernd and Reger, V. and Gilbert, J. and Heikkinen, J. and Hemmila, K.},
  title     = {Building in active thermal mass into steel structures (BATIMASS) - EUR 28166EN},
  publisher = {Publications Office of the European Union},
  address   = {Luxembourg},
  organization    = {European Commission},
  isbn      = {978-92-79-63176-4},
  issn      = {1831-9424},
  doi       = {10.2777/25999},
  pages     = {147 Seiten},
  year      = {2016},
  abstract  = {The main objective of the BATIMASS project was to address how the energy balance in relatively lightweight steel buildings can be improved by building in 'active thermal mass' (ATM) into the building fabric. This was achieved through concept design, dynamic thermal modelling and testing of a number of potentially viable systems and concepts. A significant programme of thermal simulation modelling was undertaken utilising the thermally equivalent slab (TES) concept to model the passive thermal capacity effect of profiled, composite metal floor decks. It is apparent from the modelling results that thermal mass is a highly complex phenomenon which is highly dependent upon building type, occupancy patterns, climate and many other aspects of the building design and servicing strategy. The ATM systems developed, both conceptually and for prototype testing, focussed on water-cooled composite slabs, the Cofradal floor system and the phase change material (PCM) Energain. In addition to laboratory testing of prototypes, whole building monitoring was undertaken at the Kubik building in Spain and the RWTH test building in Germany. Advanced thermal modelling was also undertaken to estimate the likely benefits of the ATM concept designs developed and for comparison with the test results. In addition to thermal testing, structural tests were conducted on composite floor specimens incorporating embedded water pipes. This Final Report presents the results of the activities carried out under this RFCS contract RFSR CT 2012 00033. The work carried out is reported in six major sections corresponding to the technical Work Packages of the project. Only summaries of the work carried out are provided in this report; all work undertaken is fully reported in the formal project deliverables.},
  language  = {en}
}
@incollection{FeldmannDoeringPyschny2016,
  author    = {Feldmann, M. and D{\"o}ring, Bernd and Pyschny, D.},
  title     = {Floor systems; Sustainabilty analyses and assessments of steel bridges},
  series = {Sustainable steel buildings : a practical guide for structures and envelopes},
  booktitle = {Sustainable steel buildings : a practical guide for structures and envelopes},
  publisher = {Wiley Blackwell},
  address   = {Chichester, West Sussex},
  isbn      = {978-1-118-74079-8 (PDF)},
  pages     = {198 -- 223},
  year      = {2016},
  language  = {en}
}
@article{DoeringRegerKuhnhenneetal.2015,
  author    = {D{\"o}ring, Bernd and Reger, Vitali and Kuhnhenne, Markus and Feldmann, Markus and Kesti, Jyrki and Lawson, Mark and Botti, Andrea},
  title     = {Steel solutions for enabling zero-energy buildings},
  series = {Steel Construction - Design and Research},
  volume    = {8},
  journal   = {Steel Construction - Design and Research},
  number    = {3},
  publisher = {Ernst \& Sohn},
  address   = {Berlin},
  issn      = {1867-0539},
  doi       = {10.1002/stco.201510029},
  pages     = {194 -- 200},
  year      = {2015},
  language  = {en}
}
@techreport{KestiMononenLautsoetal.2015,
  author    = {Kesti, Jyrki and Mononen, Tarmo and Lautso, Petteri and D{\"o}ring, Bernd and Reger, Vitali and Holopainen, R. and Jung, N. and Shemeikka, J. and Nieminen, J. and Reda, F. and Lawson, Mark and Botti, Andrea and Hall, R. and Zold, A. and Buday, T.},
  title     = {Zero energy solutions for multifunctional steel intensive commercial buildings (ZEMUSIC) - EUR 27627},
  publisher = {Publications Office of the European Union},
  address   = {Luxembourg},
  organization    = {European Commission},
  isbn      = {978-92-79-54071-4},
  issn      = {1831-9424},
  doi       = {10.2777/111520},
  pages     = {146 Seiten},
  year      = {2015},
  abstract  = {The broad commercial objective of this project was the sustainable value creation in steel building technology by addressing the ways in which significant energy reductions can be made in the operation phase of multi-storey commercial buildings. A review on energy efficient commercial buildings in Europe has been carried out consisting of several case studies from different countries. The project included development of zero-energy concepts for reducing energy demand as well as concepts for heating, cooling and ventilation systems by utilising renewable energy sources in three different climates. Also alternative structural frame solutions were developed and analyzed in respect of structural and MEP (mechanical, electrical and plumbing solutions) features. An innovative long span floor system with integrated MEP routings promises a cost effective alternative for sophisticated ventilation distribution and radiant heating and cooling systems, allowing for high energy efficiency and high quality interior climate. The report includes also review of best architectural practices for integrated renewable energy solutions including different design strategies for building facades of zero energy buildings. Interesting results and design basis are also presented for steel energy pile concept, where structural foundation piles are utilized for ground energy harvesting. Life cycle cost calculations for near zero energy office building based on developed technologies show that a near zero energy construction is also profitable. The results and work methods of the project have been summarized in the form of design guidance that offers designers the knowledge gained in a form that can be easily understood.},
  language  = {en}
}
@article{DoeringKendrickLawson2013,
  author    = {D{\"o}ring, Bernd and Kendrick, C. and Lawson, R. M.},
  title     = {Thermal capacity of composite floor slabs},
  series = {Energy and buildings},
  volume    = {Vol. 67},
  journal   = {Energy and buildings},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1872-6178 (E-Journal); 0378-7788 (Print)},
  pages     = {531 -- 539},
  year      = {2013},
  language  = {en}
}
@techreport{LawsonBaddooVanieretal.2013,
  author    = {Lawson, R.M. and Baddoo, N.R. and Vanier, G. and D{\"o}ring, Bernd and Kuhnhenne, M. and Nieminen, J. and Beguin, P. and Herbin, S. and Caroli, G. and Adetunji, I. and Kozlowski, A.},
  title     = {Renovation of buildings using steel technologies (Robust) - EUR 25335},
  publisher = {Publications Office of the European Union},
  address   = {Luxembourg},
  organization    = {European Commission},
  isbn      = {978-92-79-24950-1},
  issn      = {1831-9424},
  doi       = {10.2777/97860},
  pages     = {134 Seiten},
  year      = {2013},
  abstract  = {Robust addresses the renovation and improvement of existing residential, industrial and commercial buildings using steel-based technologies, focusing on techniques such as over-cladding, over-roofing and roof-top extensions. Steel-intensive renovation techniques currently on the market were reviewed. Performance criteria were developed for over-cladding systems meeting current regulatory standards, with guidelines on how to achieve appropriate levels of air-tightness.},
  language  = {en}
}