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[en] This report by the Swiss Federal Office of Energy (SFOE) summarises the efforts made within the framework of the federal office's 'SwissEnergy' and 'Energy 2000' programs. The history of the programs is briefly described, as are their success in bundling market forces, such as the Society for the Promotion of Heat-pumps, FWS. Further work coordinated by the SFOE includes the co-operation between the FWS and research. The office also monitors the efficiency of funding. The report stresses the responsibilities of the association in the whole chain from research through to marketing and quality assurance. The advantages offered by a fully neutral organisation with no conflicts of interest are briefly discussed
[en] Drying is one of the most energy intensive unit operations. It easily accounts for up to 15% of all industrial energy consumption. In the most drying processes heat is required to evaporate moisture which is later removed with a flow of air. The hot, humid air leaving the dryer is often considered as a waste stream, and a large fraction of energy is lost. The aim of the theoretical and experimental concept study presented here was to evaluate a method of reclaiming energy from low temperature waste streams and converting it to useful in industry saturated steam of temperature from 120 to 150 °C. Chemical heat pump concept based on the dilution and concentration of phosphoric acid was used to test the method in the laboratory. Heat of dilution and energy needed for water evaporation from the acid solution were experimentally measured. The cycle of successive processes of dilution and concentration has been experimentally confirmed. Theoretical model of the chemical heat pump was tested and coefficient of performance measured. Energy balance of the drying system and efficiency increase of the dryer supported with chemical heat pump were calculated. (Author)
[en] As a renewable energy technology, ground source heat pump (GSHP) system is high efficient for space heating and cooling in buildings. Thermal energy storage (TES) technology facilitates the efficient utilization of renewable energy sources and energy conservation. It is expected to be more prevalent in the future. GSHP application is growing rapidly as it is integrated with TES system. During the last decade, a number of investigators have conducted the studies on the designing, modeling and testing of TES assisted GSHP (GSHP–TES) system. This paper presents a review on the research and applications of GSHP integrated with TES system, including various cooling and heating storage technologies. The studies on the GSHP–TES systems are categorized into five groups including: GSHP integrated with ice storage tank, GSHP integrated with solar collectors, GSHP integrated with soil, GSHP integrated with water tank and GSHP integrated with phase change materials (PCM). However, there are still several challenges for the applications of GSHP–TES systems, such as the mechanisms, thermodynamics and performance of the unsteady and transient heat transfer of underground soil and the thermal storage process as well as control strategies of the GSHP–TES systems. Addressing these problems will strengthen the theoretical and practical understandings and facilitate more extensive applications of GSHP–TES systems. - Highlights: • Ground source heat pump combined with thermal energy storage (GSHP–TES) systems. • Theoretical and practical understandings on GSHP–TES systems. • Outline review of the available studies and identify the future research opportunities
[en] The double whammy dealt by the economic crisis and housing slump has stifled expansion of the ground-source heat pump market in many European countries. The European Union market contracted for the second year running (by 2.9% between 2009 and 2010), and this despite the fact that more than 100,000 units were sold over the twelve-month period, taking the number of installed units past the one million mark.
[fr]La crise economique ainsi que la crise immobiliere qui touchent de nombreux pays europeens ne facilitent pas l'essor du marche de la pompe a chaleur geothermique. Pour la deuxieme annee consecutive, le marche de l'union europeenne est en baisse (-2,9 % entre 2009 et 2010). il parvient tout de meme a se maintenir au-dessus des 100 000 unites vendues par an, ce qui lui permet de depasser pour la premiere fois le cap du million d'unites installees.
[en] This article discusses how in the past 10 years heat pump systems that make use of heat from the ground, air, surface water and groundwater have made a break-through in Switzerland. In particular, the important role played by heat-pump contracting is looked at. Improvements in energy efficiency in the building area are discussed and the role of the heat pump in recovering heat lost is looked at. Various models for heating contracting are discussed. These include systems where the owners of buildings just pay for the heat consumed and leave the operation and maintenance of the heat pump systems to professional operators. Examples of installations are given and the contracting model offered by the electricity utility of the Canton of Zurich, Switzerland, is described
[en] Absorption heat pumps, first developed in the 19th century, have received renewed and growing attention in the past two decades. With the increasing cost of oil and electricity, the particular features of this heat-powered cycle have made it attractive for both residential and industrial applications. Solar-powered air conditioning, gas-fired domestic cooling and waste-heat-powered temperature boosters are some of the applications on which intensive research and development has been conducted. This paper describes the operation of absorption systems and discusses several practical applications. It surveys recent advances in absorption technology, including the selection of working fluids, cycle improvements and multi-staging, and fundamentals of the combined heat and mass transfer in absorption processes. (author)
[en] In this research, a Coulomb force assisted heat pump (CF-HP) dryer was invented for the purpose of improving the drying characteristics and product quality of biomaterials. As compared to heat pump drying alone, the assistance of Coulomb force in heat pump dryer enhanced the drying rates and effective moisture diffusivity of lemon slices up to 26%, which eventually shortened the total drying time to 40%. This saved the total energy consumption of HP drying by 31.5%. High retention of vitamin C and TPC were also found in CF-HP dried slices due to mild drying temperature and fast drying rate. (Author)
[en] A series of body-centered cubic (b.c.c.) solid solution alloys have been developed which appears to be unusually suitable for several applications involving metal hydrides. It is normally very difficult to induce the body-centered cubic metals, Nb, V, and Ta, to react with hydrogen; in bulk form the reaction will simply not occur at room temperature. Alloys containing Nb exhibited very large hysteresis effects on hydride formation and thus are not suitable for most applications. However, the V-Ti based alloys showed relatively little hysteresis, and because of their unusual thermodynamic properties offer significant advantages for the specific applications discussed below. (orig./HB)
[en] Ambient heat, used by heat pump technologies, is a domestic and renewable source of energy. The utilization of ambient heat corresponds to the goals of a future oriented energy policy: (1) the reduction of primary energy requirements and imports, especially oil, (2) the increased use of domestic renewable energies, (3) reduction of CO2-emissions. The efficient use of heat pumps for space heating is determined by a number of criteria: low as possible supply temperatures of the heating system, appropriate designing and efficient control. In 1990, the number of heat pumps installed in Austria amounted to a total of about 96000 systems. The present contribution of heat pump technology to the energy supply amounts to about 950 GWh per year (December 1990). This amount corresponds to a saved quantity of oil of about 180000 tons per year. (author)