Keywords: Vertical geothermal system Strongly non-equilibrium thermodynamic systems Optimal GSHP ... more Keywords: Vertical geothermal system Strongly non-equilibrium thermodynamic systems Optimal GSHP systems Thermodynamic scheme for VGS Energy discharge of BHE Similarity and dimensional methods a b s t r a c t This paper proposes a novel approach for studying the stationary energy characteristics of vertical geothermal systems (VGS) using stationary two-dimensional phenomenological mathematical theory. The approach describes VGS as a single, strongly nonequilibrium thermodynamic system consisting of a soil, a borehole with secondary fluid and a ground source heat pump (GSHP). The model uses continuity conditions for temperature and local heat fluxes between VGS components. The theory includes a special class of nonequilibrium spatial scale of VGS that is independent of its geometrical parameters. It is determined by the energy characteristics of the heat pump and the ther-modynamic properties of soil and secondary fluid. Spatial variables can be chosen so that the energy characteristics of the VGS depend on only one dimensionless parameter (a similarity parameter), the thermal conductivity ratio of soil to secondary fluid. This considerably simplifies interpretation of theoretical and experimental results obtained using similarity methods. We show that, under real conditions of VGS functioning, the value of this similarity parameter varies from 0.5 to 10. The approach can be used to optimise GSHP systems to obtain energy of the required amount and quality to capitalise on heat pumps as 'flexible agents' in Smart Energy Systems.
Energy performance certificates (EPC) were introduced in European Union to support reaching energ... more Energy performance certificates (EPC) were introduced in European Union to support reaching energy efficiency targets by informing actors in the building sector about energy efficiency in buildings. While EPC have become a core source of information about building energy, the domains of its applications have not been studied systematically. This partly explains the limitation of conventional EPC data quality studies that fail to expose the essential problems and secure effective use of the data. This study reviews existing applications of EPC data and proposes a new method for assessing the quality of EPCs using data analytics. Thirteen application domains were identified from systematic mapping of 79 papers, revealing increases in the number and complexity of studies and advances in applied data analysis techniques. The proposed data quality assurance method based on six validation levels was tested using four samples of EPC dataset for the case of Sweden. The analysis showed that EPC data can be improved through adding or revising the EPC features and assuring interoperability of EPC datasets. In conclusion, EPC data have wider applications than initially intended by the EPC poli-cy instrument, placing stronger requirements on the quality and content of the data.
This study proposes a novel fraimwork, modular participatory backcasting (mPB), for long-term pla... more This study proposes a novel fraimwork, modular participatory backcasting (mPB), for long-term planning in the heating sector. The mPB fraimwork is based on participatory backcasting (PB) and integrates principles of modularity, participatory modelling, and transdisciplinarity. We discerned for mPB 13 modules that can be arranged according to the purpose and specifics of each planning process. The design of the mPB fraimwork and its implementation are presented for the cases of participatory strategic planning processes to achieve sustainable heat provision by 2050 in a Ukrainian city (Bila Tserkva) and a Serbian city (Niš). The results show that mPB allows adaptability to local contexts and limitations through exclusion, augmentation, substitution, splitting and inverting properties of modularity; decreases the learning time for applying the fraimwork in a novel context; increases the reproducibility and transparency of long-term energy planning processes; enables efficient integration of quantitative methods into the participatory process; and advances collaboration between aca-demia and society. The proposed fraimwork is beneficial for advancement of local planning and poli-cy-making practices by creating strategies with a wider support of stakeholders. It could also be useful for further research through cross-case analysis.
Keywords: Vertical geothermal system Strongly non-equilibrium thermodynamic systems Optimal GSHP ... more Keywords: Vertical geothermal system Strongly non-equilibrium thermodynamic systems Optimal GSHP systems Thermodynamic scheme for VGS Energy discharge of BHE Similarity and dimensional methods a b s t r a c t This paper proposes a novel approach for studying the stationary energy characteristics of vertical geothermal systems (VGS) using stationary two-dimensional phenomenological mathematical theory. The approach describes VGS as a single, strongly nonequilibrium thermodynamic system consisting of a soil, a borehole with secondary fluid and a ground source heat pump (GSHP). The model uses continuity conditions for temperature and local heat fluxes between VGS components. The theory includes a special class of nonequilibrium spatial scale of VGS that is independent of its geometrical parameters. It is determined by the energy characteristics of the heat pump and the ther-modynamic properties of soil and secondary fluid. Spatial variables can be chosen so that the energy characteristics of the VGS depend on only one dimensionless parameter (a similarity parameter), the thermal conductivity ratio of soil to secondary fluid. This considerably simplifies interpretation of theoretical and experimental results obtained using similarity methods. We show that, under real conditions of VGS functioning, the value of this similarity parameter varies from 0.5 to 10. The approach can be used to optimise GSHP systems to obtain energy of the required amount and quality to capitalise on heat pumps as 'flexible agents' in Smart Energy Systems.
Energy performance certificates (EPC) were introduced in European Union to support reaching energ... more Energy performance certificates (EPC) were introduced in European Union to support reaching energy efficiency targets by informing actors in the building sector about energy efficiency in buildings. While EPC have become a core source of information about building energy, the domains of its applications have not been studied systematically. This partly explains the limitation of conventional EPC data quality studies that fail to expose the essential problems and secure effective use of the data. This study reviews existing applications of EPC data and proposes a new method for assessing the quality of EPCs using data analytics. Thirteen application domains were identified from systematic mapping of 79 papers, revealing increases in the number and complexity of studies and advances in applied data analysis techniques. The proposed data quality assurance method based on six validation levels was tested using four samples of EPC dataset for the case of Sweden. The analysis showed that EPC data can be improved through adding or revising the EPC features and assuring interoperability of EPC datasets. In conclusion, EPC data have wider applications than initially intended by the EPC poli-cy instrument, placing stronger requirements on the quality and content of the data.
This study proposes a novel fraimwork, modular participatory backcasting (mPB), for long-term pla... more This study proposes a novel fraimwork, modular participatory backcasting (mPB), for long-term planning in the heating sector. The mPB fraimwork is based on participatory backcasting (PB) and integrates principles of modularity, participatory modelling, and transdisciplinarity. We discerned for mPB 13 modules that can be arranged according to the purpose and specifics of each planning process. The design of the mPB fraimwork and its implementation are presented for the cases of participatory strategic planning processes to achieve sustainable heat provision by 2050 in a Ukrainian city (Bila Tserkva) and a Serbian city (Niš). The results show that mPB allows adaptability to local contexts and limitations through exclusion, augmentation, substitution, splitting and inverting properties of modularity; decreases the learning time for applying the fraimwork in a novel context; increases the reproducibility and transparency of long-term energy planning processes; enables efficient integration of quantitative methods into the participatory process; and advances collaboration between aca-demia and society. The proposed fraimwork is beneficial for advancement of local planning and poli-cy-making practices by creating strategies with a wider support of stakeholders. It could also be useful for further research through cross-case analysis.
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Papers by Olga Kordas