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[en] The manned deep-space exploration is a hot topic of the current space activities. The continuous supply of thermal and electrical energy for the scientific equipment and human beings is a crucial issue for the lunar outposts. Since the night lasts for periods of about 350 h at most locations on the lunar surface, massive energy storage is required for continuous energy supply during the lengthy lunar night and the in-situ resource utilization is demanded. A lunar based solar thermal power system with regolith thermal storage is presented in this paper. The performance analysis is carried out by the finite-time thermodynamics to take into account major irreversible losses. The influences of some key design parameters are analyzed for system optimization. The analytical results shows that the lunar based solar thermal power system with regolith thermal storage can meet the requirement of the continuous energy supply for lunar outposts. - Highlights: • A lunar based solar thermal power system with regolith thermal storage is presented. • The performance analysis is carried out by the finite-time thermodynamics. • The influences of some key design parameters are analyzed.
[en] The results of the EIR collector test series of the summers 1978 and 1979 are presented. In total, there are 37 different collectors available on the Swiss market. The results are compared with those from the IEA (International Energy Agency) of presuggested reference collectors. Test methods are described and also the construction of the test bench. Also, briefly described is a development method for the calculation of gross heat yield from solar collectors. Then the characteristics of the reference collectors in connection with the test periods are considered, and their role in the calculation of results of single collector test series explained. A description of the spectral photometer is given. (A.N.K.)
[en] The author presents tables of medium-usage solar collectors in connection with their characteristic values: optical efficiency during perpendicular light leak, and thermal loss factor for small differences between operating and external temperatures. With the aid of these data, each prospective buyer can quickly and easily determine the monthly gross heat yield for various collector types. (A.N.K.)
[en] The test results of the summer 1980 test on solar collectors are summarised. Apart from the 16 collectors tested under contract, two were investigated as a reference serving flat collectors, e.g. for the area of International Energy Agency (IEA), two were evacuated cylindrical collectors. The report allows the comparison of heat power outputs of the different products on the basis of the measured optical and thermal data values. (A.N.K.)
[en] Results of analysis of about 30 sources (USA, Germany, Greece, Denmark, Israel, EEC) were used to distinguish some characteristic features of foreign legislation, concerning use of renewable energy sources
[ru]На основании результатов анализа около 30 истоников (США, ФРГ, Греция, Дания, Израиль и ЕЭС) выделены некоторые характерные элементы зарубежного законодательства в использовании возобновляемых энергетических ресурсов
[en] Seasonal storage for solar energy have been the object of intensive theoretical studies and practical experiments. Within the frame of the research programme of the International Energy Agency 11 objects were set up and tested in practice. It was the aim of this research and demonstration projects to examine thermal long term storage for the use of solar energy and waste heat from industrial processes. In the following the actual state of the art of long term storage of solar energy for district heating in buildings will be described and possibilities of its use in Austria will be assessed. (author)
[en] Highlights: • The interaction between multiple boreholes is presented as an arising issue. • Thermal interaction among boreholes in long-term system operation is examined. • Effect of thermal interaction on heat pump COP is examined. • Borehole stores/removes heat in the ground under a periodic ground heat profile. • The analytical model is validated with a numerical finite volume approach. - Abstract: A semi-analytical model that couples a model outside the borehole with one inside the borehole is proposed. To examine the effect of temperature rise in the soil surrounding a vertical ground heat exchanger on the performance of an associated ground heat pump, the heat pump model should be coupled to the model inside the borehole and the conduction heat transfer model outside the borehole. The running fluid temperature, the borehole wall temperature and the heat load profile are the main coupling parameters between the three models. The results of the analytical model are compared with ones of a finite volume numerical model
[en] Solar resource estimation risk is one of the main solar PV project risks that influences lender’s decision in providing financing and in determining the cost of capital. More recently, a number of measures have emerged to mitigate this risk. The study focuses on solar industry’s best practice energy resource estimation and assesses its financing implications to the 27 MWp solar PV project study in Brunei Darussalam. The best practice in resource estimation uses multiple data sources through the measure-correlate-predict (MCP) technique as compared with the standard practice that rely solely on modelled data source. The best practice case generates resource data with lower uncertainty and yields superior high-confidence energy production estimate than the standard practice case. Using project financial parameters in Brunei Darussalam for project financing and adopting the international debt-service coverage ratio (DSCR) benchmark rates, the best practice case yields DSCRs that surpass the target rates while those of standard practice case stay below the reference rates. The best practice case could also accommodate higher debt share and have lower levelized cost of electricity (LCOE) while the standard practice case would require a lower debt share but having a higher LCOE. - Highlights: •Best practice solar energy resource estimation uses multiple datasets. •Multiple datasets are combined through measure-correlate-predict technique. •Correlated data have lower uncertainty and yields superior high-confidence energy production. •Best practice case yields debt-service coverage ratios (DSCRs) that surpass the benchmark rates. •Best practice case accommodates high debt share and have low levelized cost of electricity.
[en] Problem of materials for solar heat and photoelectric systems is considered. The processes determining photovoltaic effect are considered. Perspective materials and their characterististics are reviewed (silicon, gallium arsenide, p-Cusub(x)S/n-CdS thin-film structures, elements on the base of cadmium telluride, zinc phosphides)