TY - JOUR A1 - Agrafiotis, Christos C. A1 - Mavroidis, Ilias A1 - Konstandopoulos, Athansios G. A1 - Hoffschmidt, Bernhard A1 - Stobbe, Per A1 - Romero, Manuel A1 - Fernandez-Quero, Valerio T1 - Evaluation of porous silicon carbide monolithic honeycombs as volumetric receivers/collectors of concentrated solar radiation JF - Solar energy materials and solar cells Y1 - 2007 SN - 1879-3398 (E-Journal); 0927-0248 (Print) VL - Vol. 91 IS - Iss. 6 SP - 474 EP - 488 ER - TY - CHAP A1 - Fend, Thomas A1 - Hoffschmidt, Bernhard A1 - Reutter, Oliver A1 - Sauerhering, Jörg A1 - Pitz-Paal, Robert T1 - Gas flow in hot porous materials: the solar air receiver and spin-off applications T2 - Proceedings of the 4th Nanochannels, Microchannels and Minichannels - 2006 : presented at 4th Nanochannels, Microchannels and Minichannels, June 19 - 21, 2006, Limerick, Ireland Y1 - 2006 SN - 0-7918-4760-8 SP - 507 EP - 514 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Hoffschmidt, Bernhard A1 - Schwarzer, Klemens A1 - Späte, Frank A1 - Kötter, Jens A1 - Ebert, Miriam A1 - Sierck, Olaf T1 - Development of a small modular parabolic trough collector T2 - 13th International Symposium Concentrated Solar Power and Chemical Energy Technologies : SolarPaces : June 20 - 23, 2006, Seville, Spain Y1 - 2006 SN - 8478345191 PB - SolarPaces CY - [o.O.] ER - TY - CHAP A1 - Beckmöller, S. A1 - Wolters, J. A1 - Breitbach, Gerd A1 - Penkalla, H. J. A1 - Schubert, F. T1 - Microstructural dependent constitutive equation for inelastic analysis of internally cooled IN 738 LC turbine blades T2 - Materials for advanced power engineering 1994 : proceedings of a conference held in Liege, Belgium, 3 - 6 Oct. 1994 Y1 - 1995 SN - 0792330749 SP - 829 EP - 839 PB - Kluwer CY - Dordrecht ER - TY - CHAP A1 - Fricke, Barbara A1 - Hoffschmidt, Bernhard T1 - Ecobalance of a solar thermal tower power plant with volumetric receiver T2 - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France Y1 - 2010 SP - 87 EP - 88 PB - Soc. OSC CY - Saint Maur ER - TY - CHAP A1 - Schwarzbözl, Peter A1 - Pomp, Stefan A1 - Koll, Gerrit A1 - Hennecke, Klaus A1 - Hartz, Thomas A1 - Schmitz, Mark A1 - Hoffschmidt, Bernhard T1 - The solar tower Jülich - first operational experiences and test results T2 - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France Y1 - 2010 SP - 8 EP - 9 PB - Soc. OSC CY - Saint Maur ER - TY - CHAP A1 - Pomp, Stefan A1 - Schwarzbözl, Peter A1 - Koll, Gerrit A1 - Hennecke, Klaus A1 - Schmitz, Mark A1 - Hoffschmidt, Bernhard T1 - Advanced concept for a solar thermal power plant with open volumetric air receiver T2 - SolarPACES 2010 : the CSP Conference: electricity, fuels and clean water from concentrated solar energy ; 21 to 24 September 2010, Perpignan, France Y1 - 2010 SP - 97 EP - 98 PB - Soc. OSC CY - Saint Maur ER - TY - JOUR A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Abdurakhmanov, Aydemir A1 - Turichin, Gleb A1 - Valdaitseva, Elena A1 - Bach, Friedrich-Wilhelm A1 - Hassel, Thomas A1 - Beniyashi, Alexander T1 - Investigation of factors influencing the formation of weld defects in non-vacuum electron beam welding JF - The Paton welding journal N2 - The influence of welding condition parameters and properties of material on formation of defects, such as humping and undercuts, in non-vacuum electron beam welding was investigated. The influence of separate welding parameters on the quality of welds was determined. Y1 - 2012 SN - 0957-798X VL - 2012 IS - 2 SP - 11 EP - 18 PB - Paton Publishing House CY - Kiev ER - TY - JOUR A1 - Vieira da Silva, Maria Eugenia A1 - Schwarzer, Klemens A1 - Hoffschmidt, Bernhard A1 - Pinheiro Rodrigues, Frederico A1 - Schwarzer, Tarik A1 - Costa Rocha, Paulo Alexandre T1 - Mass transfer correlation for evaporation–condensation thermal process in the range of 70 °C–95 °C JF - Renewable energy Y1 - 2013 SN - 1879-0682 (E-Journal); 0960-1481 (Print) VL - Vol. 53 SP - 174 EP - 179 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Hagenkamp, Markus A1 - Blanke, Tobias A1 - Döring, Bernd T1 - Thermoelectric building temperature control: a potential assessment JF - International Journal of Energy and Environmental Engineering N2 - 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. Y1 - 2021 U6 - https://doi.org/10.1007/s40095-021-00424-x N1 - Corresponding author: Markus Hagenkamp VL - 13 SP - 241 EP - 254 PB - Springer CY - Berlin ER -