The Experts below are selected from a list of 201 Experts worldwide ranked by ideXlab platform

C. Butcher - One of the best experts on this subject based on the ideXlab platform.

  • experience with fully operational Solar driven 10 ton libr h2o single effect absorption cooling system in thailand
    Renewable Energy, 2008
    Co-Authors: Anan Pongtornkulpanich, M Amornkitbamrung, Sirichai Thepa, C. Butcher
    Abstract:

    A Solar-driven 10-ton LiBr/H2O single-effect absorption cooling system has been designed and installed at the School of Renewable Energy Technology (SERT), Phitsanulok, Thailand. Construction took place in 2005, after which this system became fully operational and has been supplying cooling for our main testing building's air-conditioning. Data on the system's operation were collected during 2006 and analyzed to find the extent to which Solar energy replaced conventional energy sources. Here, we present these data and show that the 72m2 evacuated tube Solar Collector delivered a yearly average Solar fraction of 81%, while the remaining 19% of thermal energy required by the chiller was supplied by a LPG-fired backup heating unit. We also show that the economics of this cooling system are dominated by the initial cost of the Solar Collector Array and the absorption chiller, which are significantly higher than that of a similar-size conventional VCC system.

  • Experience with fully operational Solar-driven 10-ton LiBr/H2O single-effect absorption cooling system in Thailand
    Renewable Energy, 2008
    Co-Authors: Anan Pongtornkulpanich, M Amornkitbamrung, Sirichai Thepa, C. Butcher
    Abstract:

    Abstract A Solar-driven 10-ton LiBr/H 2 O single-effect absorption cooling system has been designed and installed at the School of Renewable Energy Technology (SERT), Phitsanulok, Thailand. Construction took place in 2005, after which this system became fully operational and has been supplying cooling for our main testing building's air-conditioning. Data on the system's operation were collected during 2006 and analyzed to find the extent to which Solar energy replaced conventional energy sources. Here, we present these data and show that the 72 m 2 evacuated tube Solar Collector delivered a yearly average Solar fraction of 81%, while the remaining 19% of thermal energy required by the chiller was supplied by a LPG-fired backup heating unit. We also show that the economics of this cooling system are dominated by the initial cost of the Solar Collector Array and the absorption chiller, which are significantly higher than that of a similar-size conventional VCC system.

Simon Furbo - One of the best experts on this subject based on the ideXlab platform.

  • A Solar combi-system utilizing stable supercooling of sodium acetate trihydrate for heat storage: Numerical performance investigation
    Applied Energy, 2019
    Co-Authors: Gerald Englmair, Jianhua Fan, Christoph Moser, Hermann Schranzhofer, Simon Furbo
    Abstract:

    Abstract To reduce the energy consumption of buildings significantly, a novel Solar combi-system with short and long-term heat storage has been developed. A system prototype with 22.4 m2 (aperture) evacuated tubular Collectors, a 735 L water tank and 4 phase change material (PCM) units each containing 150 L sodium acetate trihydrate composite has been built. Experimental investigation has shown advantages of utilization of stable supercooling of sodium acetate trihydrate in spring and autumn. In this paper, a newly developed numerical model was used to investigate the performance potential of the system with combined utilization of the water tank and the PCM units, including on-demand crystallization of supercooled sodium acetate trihydrate composites. PCM units, the water tank and the Collector circuit models were validated with measurement data from system demonstration. Space heating and hot water demand patterns of a Danish single-family Passive House with a yearly heat demand of 3723 kWh were applied. Results showed that a 56% annual Solar fraction of heat supply was achieved with the prototype specifications. A 69% Solar fraction could be achieved with an optimized scenario including a 15% increased hot water demand. Sensitivity analysis of component sizing showed that PCM units of 200 L can be more efficiently used with a 0.6 m3 water tank. Optimal Solar Collector Array tilt was 70°. Aperture areas between 12.8 and 22.4 m2 were found adequate for frequent utilization of a PCM volume up to 1 m3. Thus, the PCM heat storage capacity could be utilized at least 5.5 times a year. With a 22.4 m2 Collector area and 5 PCM units of 200 L each, a Solar fraction of 71% was calculated for the annual heat supply. Assuming full charge of a 0.6 m3 water tank and 2.8 m3 of sodium acetate trihydrate composite by electricity at the beginning of the year, the system could run 18 days without need for auxiliary heating. Thus, in periods without Solar Collector power available, generation maxima of wind power could be utilized. In conclusion, building heat demand could be covered close to 100% by renewable energy resources.

  • Design and functionality of a segmented heat-storage prototype utilizing stable supercooling of sodium acetate trihydrate in a Solar heating system
    Applied Energy, 2018
    Co-Authors: Gerald Englmair, Mark Dannemand, Simon Furbo, Christoph Moser, Jianhua Fan
    Abstract:

    Abstract A Solar heating system with 22.4 m2 of Solar Collectors, a heat storage prototype consisting of four 200 kg phase-change material (PCM) storage units, and a 735 L water tank was designed to improve Solar heat supply in single-family houses. The PCM storage utilized stable supercooling of sodium acetate trihydrate composites to conserve the latent heat of fusion for long-term heat storage. A control strategy directed heat from a Solar Collector Array to either the PCM storage or a water buffer storage. Several PCM units had to be charged in parallel when the Solar Collector output peaked at 16 kW. A single unit was charged with 27.4 kWh of heat within four hours on a sunny day, and the PCM temperature increased from 20 °C to 80 °C. The sensible heat from a single PCM unit was transferred to the water tank starting with about 32 kW of thermal power after it had fully melted at 80 °C. A mechanical seed crystal injection device was used to initialize the crystallisation of the sodium acetate trihydrate after it had supercooled to room temperature. The unit discharge during solidification peaked at 8 kW. Reliable supercooling was achieved in three of the four units. About 80% of latent heat of fusion was transferred from PCM units after solidification of supercooled sodium acetate trihydrate to the water tank within 5 h. Functionality tests with practical operation conditions on the novel, modular heat-storage configuration showed its applicability for domestic hot water supply and space heating.

  • simulation of a Solar Collector Array consisting of two types of Solar Collectors with and without convection barrier
    Energy Procedia, 2015
    Co-Authors: Federico Bava, Simon Furbo, Bengt Perers
    Abstract:

    Abstract The installed area of Solar Collectors in Solar heating fields is rapidly increasing in Denmark. In this scenario even relatively small performance improvements may lead to a large increase in the overall energy production. Both Collectors with and without polymer foil, functioning as convection barrier, can be found on the Danish market. Depending on the temperature level at which the two types of Collectors operate, one can perform better than the other. This project aimed to study the behavior of a 14 Solar Collector row made of these two different kinds of Collectors, in order to optimize the composition of the row. Actual Solar Collectors available on the Danish market (models HT-SA and HT-A 35-10 manufactured byARCON Solar A/S) were used for this analysis. To perform the study, a simulation model in TRNSYS was developed based onthe Danish Solar Collector field in Braedstrup. A parametric analysis was carried out by modifying the composition of the row, in order to find both the energy and economy optimum.

Anan Pongtornkulpanich - One of the best experts on this subject based on the ideXlab platform.

  • experience with fully operational Solar driven 10 ton libr h2o single effect absorption cooling system in thailand
    Renewable Energy, 2008
    Co-Authors: Anan Pongtornkulpanich, M Amornkitbamrung, Sirichai Thepa, C. Butcher
    Abstract:

    A Solar-driven 10-ton LiBr/H2O single-effect absorption cooling system has been designed and installed at the School of Renewable Energy Technology (SERT), Phitsanulok, Thailand. Construction took place in 2005, after which this system became fully operational and has been supplying cooling for our main testing building's air-conditioning. Data on the system's operation were collected during 2006 and analyzed to find the extent to which Solar energy replaced conventional energy sources. Here, we present these data and show that the 72m2 evacuated tube Solar Collector delivered a yearly average Solar fraction of 81%, while the remaining 19% of thermal energy required by the chiller was supplied by a LPG-fired backup heating unit. We also show that the economics of this cooling system are dominated by the initial cost of the Solar Collector Array and the absorption chiller, which are significantly higher than that of a similar-size conventional VCC system.

  • Experience with fully operational Solar-driven 10-ton LiBr/H2O single-effect absorption cooling system in Thailand
    Renewable Energy, 2008
    Co-Authors: Anan Pongtornkulpanich, M Amornkitbamrung, Sirichai Thepa, C. Butcher
    Abstract:

    Abstract A Solar-driven 10-ton LiBr/H 2 O single-effect absorption cooling system has been designed and installed at the School of Renewable Energy Technology (SERT), Phitsanulok, Thailand. Construction took place in 2005, after which this system became fully operational and has been supplying cooling for our main testing building's air-conditioning. Data on the system's operation were collected during 2006 and analyzed to find the extent to which Solar energy replaced conventional energy sources. Here, we present these data and show that the 72 m 2 evacuated tube Solar Collector delivered a yearly average Solar fraction of 81%, while the remaining 19% of thermal energy required by the chiller was supplied by a LPG-fired backup heating unit. We also show that the economics of this cooling system are dominated by the initial cost of the Solar Collector Array and the absorption chiller, which are significantly higher than that of a similar-size conventional VCC system.

Jianhua Fan - One of the best experts on this subject based on the ideXlab platform.

  • A Solar combi-system utilizing stable supercooling of sodium acetate trihydrate for heat storage: Numerical performance investigation
    Applied Energy, 2019
    Co-Authors: Gerald Englmair, Jianhua Fan, Christoph Moser, Hermann Schranzhofer, Simon Furbo
    Abstract:

    Abstract To reduce the energy consumption of buildings significantly, a novel Solar combi-system with short and long-term heat storage has been developed. A system prototype with 22.4 m2 (aperture) evacuated tubular Collectors, a 735 L water tank and 4 phase change material (PCM) units each containing 150 L sodium acetate trihydrate composite has been built. Experimental investigation has shown advantages of utilization of stable supercooling of sodium acetate trihydrate in spring and autumn. In this paper, a newly developed numerical model was used to investigate the performance potential of the system with combined utilization of the water tank and the PCM units, including on-demand crystallization of supercooled sodium acetate trihydrate composites. PCM units, the water tank and the Collector circuit models were validated with measurement data from system demonstration. Space heating and hot water demand patterns of a Danish single-family Passive House with a yearly heat demand of 3723 kWh were applied. Results showed that a 56% annual Solar fraction of heat supply was achieved with the prototype specifications. A 69% Solar fraction could be achieved with an optimized scenario including a 15% increased hot water demand. Sensitivity analysis of component sizing showed that PCM units of 200 L can be more efficiently used with a 0.6 m3 water tank. Optimal Solar Collector Array tilt was 70°. Aperture areas between 12.8 and 22.4 m2 were found adequate for frequent utilization of a PCM volume up to 1 m3. Thus, the PCM heat storage capacity could be utilized at least 5.5 times a year. With a 22.4 m2 Collector area and 5 PCM units of 200 L each, a Solar fraction of 71% was calculated for the annual heat supply. Assuming full charge of a 0.6 m3 water tank and 2.8 m3 of sodium acetate trihydrate composite by electricity at the beginning of the year, the system could run 18 days without need for auxiliary heating. Thus, in periods without Solar Collector power available, generation maxima of wind power could be utilized. In conclusion, building heat demand could be covered close to 100% by renewable energy resources.

  • Design and functionality of a segmented heat-storage prototype utilizing stable supercooling of sodium acetate trihydrate in a Solar heating system
    Applied Energy, 2018
    Co-Authors: Gerald Englmair, Mark Dannemand, Simon Furbo, Christoph Moser, Jianhua Fan
    Abstract:

    Abstract A Solar heating system with 22.4 m2 of Solar Collectors, a heat storage prototype consisting of four 200 kg phase-change material (PCM) storage units, and a 735 L water tank was designed to improve Solar heat supply in single-family houses. The PCM storage utilized stable supercooling of sodium acetate trihydrate composites to conserve the latent heat of fusion for long-term heat storage. A control strategy directed heat from a Solar Collector Array to either the PCM storage or a water buffer storage. Several PCM units had to be charged in parallel when the Solar Collector output peaked at 16 kW. A single unit was charged with 27.4 kWh of heat within four hours on a sunny day, and the PCM temperature increased from 20 °C to 80 °C. The sensible heat from a single PCM unit was transferred to the water tank starting with about 32 kW of thermal power after it had fully melted at 80 °C. A mechanical seed crystal injection device was used to initialize the crystallisation of the sodium acetate trihydrate after it had supercooled to room temperature. The unit discharge during solidification peaked at 8 kW. Reliable supercooling was achieved in three of the four units. About 80% of latent heat of fusion was transferred from PCM units after solidification of supercooled sodium acetate trihydrate to the water tank within 5 h. Functionality tests with practical operation conditions on the novel, modular heat-storage configuration showed its applicability for domestic hot water supply and space heating.

Ruzhu Wang - One of the best experts on this subject based on the ideXlab platform.

  • Theoretical analysis and case study on Solar driven two-stage rotary desiccant cooling system combined with geothermal heat pump
    Energy Procedia, 2015
    Co-Authors: Xian Li, Ruzhu Wang
    Abstract:

    Abstract In this paper, a Solar hybrid desiccant air conditioning system, which combines the technologies of two-stage desiccant cooling system and geothermal heat pump together, has been configured and theoretically analyzed. The hybrid system mainly includes a two-stage desiccant cooling system with design cooling capacity of 80 kW, a geothermal heat pump for fresh air handling with 75 kW in nominal cooling capacity, a geothermal heat pump for capillary radiation terminal with cooling capacity of 244 kW, an evacuated tubular Solar Collector Array of 530 m 2 , a hot water storage tank and a cooling tower. Performance model of the system has been created in TRNSYS simulation studio. The aim of this paper is to evaluate the performance of the Solar hybrid air conditioning system, thereby providing useful data for practical application in the demonstration project. Simulation results show that, under typical weather condition, the Solar driven desiccant cooling unit can achieve an average cooling capacity of 70 kW, which contributes 31.4% of the cooling capacity provided by the hybrid system. Corresponding average thermal COP is about0.83 under Shanghai weather conditions.

  • An Experimentaland Simulation Study on Performance of Solar-Powered Floor Heating System
    Proceedings of ISES World Congress 2007 (Vol. I – Vol. V), 2008
    Co-Authors: Zhaopei Song, Ruzhu Wang, Xiaoqiang Zhai
    Abstract:

    Performance of a Solar-powered floor heating system serving was studied. This system utilized a 96m2 Solar Collector Array as heat source and servers an office area of 170 m2. Experiments have been going on from Dec 2006 to Mar 2007 under various conditions, and the result showed that this system runs well during that winter with average room temperature maintained above 16°C except for continuous overcast days.