Design and Application of a Seasonal Solar Soil Heat Storage System Applied in Greenhouse Heating

A seasonal solar soil heat storage (SSSHS) system applied in greenhouse heating has been designed and introduced. The system consists of solar collector subsystem, soil heat storage subsystem, greenhouse heating subsystem, hydronic subsystem and control subsystem. By applying soil heat storage, solar energy stored in the soil under the greenhouse can be transferred and utilized in winter to realize the utilization of cross-seasonal energy. TRNSYS is used to simulate the process and effect in the system of the solar energy collection and soil heat storage in Shanghai, and the simulation is calibrated to improve the precision of the TRNSYS model. When the indoor air temperature of the greenhouse is kept at 12°C throughout the year, the energy saving by using the SSSHS system in Shanghai can be 46.2kWh/(m2∙year).

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Experimental Investigation on a Latent Heat Thermal Storage Unit for Solar Cooling Application

Green ◽

10.1515/green.2011.018 ◽

2011 ◽

Vol 1 (2) ◽

Author(s):

L. Chidambaram ◽

A. S. Ramana ◽

G. Kamaraj ◽

R. Velraj

Keyword(s):

Solar Energy ◽

Latent Heat ◽

Solar Collector ◽

Heat Storage ◽

Storage System ◽

Thermal Storage ◽

Environmental Crisis ◽

Storage Unit ◽

Latent Heat Storage ◽

Solar Cooling

AbstractConventional cooling technologies that utilize harmful refrigerants consume more energy and cause peak loads leading to negative environmental impacts. As the world grapples with the energy and environmental crisis, there is an urgent need to develop and promote environmentally benign sustainable cooling technologies. Solar cooling is one such promising technology, given the fact that solar energy is the cheapest and most widely available renewable energy that matches the cooling load requirements. However thermal storage systems are essential to overcome the disadvantage of the intermittent nature of solar energy and variations in the cooling demand. The enhanced utilization of solar energy and other consequences of thermal storage integrated systems have gained the attention of researchers in recent years. The concept of combined sensible and latent heat storage system is successfully introduced in several applications and it has many advantages. This paper presents the performance of the solar collector system and the charging characteristics of a PCM based latent heat thermal storage unit, which is designed to provide continuous supply of heat for the operation of 1 kW vapor absorption refrigeration unit. Investigations on PCM integrated thermal storage system have revealed improvement in heat storage capacity, lower heat loss and an increased solar collector efficiency due to better thermal stratification.

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Energy Saving Analysis on Solar Capillary Radiation Heating System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.2807 ◽

2013 ◽

Vol 448-453 ◽

pp. 2807-2814 ◽

Cited By ~ 1

Author(s):

Jin Shun Wu ◽

Song Pan ◽

Jun Wei ◽

Hong Wei Liu ◽

Yi Xuan Wei ◽

...

Keyword(s):

Water Temperature ◽

Energy Saving ◽

Air Temperature ◽

Indoor Air ◽

Solar Collector ◽

Experimental System ◽

Heating System ◽

Capillary Network ◽

Water Volume ◽

Low Grade

Radiation capillary used as air conditioning terminal lower the demand of heating water temperature. In additional, solar collectors could also supply amount of low grade energy for heating. Meanwhile, solar is a kind of renewable, sustainable and environment friendly energy. It will save a massive of conventional energy if make full use of solar for heating. In this paper, an experimental system made of solar collector, capillary network and pump was built up and tested. According to thermal load of experimental room, both solar collector area and capillary network area are calculated, and circulating water temperature was analyzed in detail. A summary is given about characteristics of heat storage and release of solar collector, indoor air temperature varying and amount of energy saving. The key factors affect efficiency of collector includes water volume, water temperature in tanker and indoor air temperature. The results show that the solar system can well meet the heating demand and the effect of energy saving is very significant compared to common heating system.

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Maximizing Energy Saving by Solar Power based Optimal Supply Side Management

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.l3300.1081219 ◽

2019 ◽

Vol 8 (12) ◽

pp. 388-395

Keyword(s):

Solar Energy ◽

Energy Saving ◽

Electrical Energy ◽

Current Control ◽

Power Supplies ◽

Control Scheme ◽

Physical Output ◽

And Control ◽

Current Energy ◽

A Current

Energy saving can be maximized by rectifying the intermediate conversion processes involved during the utilization of solar energy. The system eliminates the transformation of electrical form of solar energy into another form by directly utilizing its electrical energy in the management and control of power supplies obtained from renewable (solar) and conventional (mains) energy sources. A current control scheme is presented in which current delivered by solar supply is used to control the current in mains supply in such a way that both currents are inversely proportional to each other. Any increment in solar current opposes mains current in the same proportion and vice versa. A balanced common physical output is resulted from the electrical load supplied by each source separately. A natural variation in solar radiation is utilized to fluctuate the solar current which is further used to change the mains current. Energy saving is maximized in this supply management by the optimal utilization of solar energy.

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Performance of a bridge deck as solar collector in a thermal energy storage system

E3S Web of Conferences ◽

10.1051/e3sconf/202020507009 ◽

2020 ◽

Vol 205 ◽

pp. 07009

Author(s):

Di Wu ◽

Gangqiang Kong ◽

Hanlong Liu ◽

Xi Zhu ◽

Hefu Pu

Keyword(s):

Wind Speed ◽

Solar Energy ◽

Solar Collector ◽

Bridge Deck ◽

Collection Efficiency ◽

Numerical Models ◽

Storage System ◽

Structural Response ◽

Radiation Energy ◽

Heat Element

Solar energy can be stored in subsurface and extracted to melt snow and deice in winter. In summer, the bridge deck heat element in a bridge deicing system could serve as a solar energy collector without additional cost. Numerical models were developed in this study to investigate the performance of a bridge deck solar collector. The effects of radiation intensity and wind speed on the solar energy collection efficiency of a bridge deck solar energy collector were discussed and analyzed. The results show that the temperature of the slab was decreased during the solar collection process, and the solar energy collection efficiency of the bridge deck solar collector was about 26~47%. The collection efficiency of solar energy at a given wind speed was increased with the decreasing of the radiation energy, and this effect was more pronounced when the wind speed was higher. The solar energy collection was beneficial to the durability of the top asphalt layer as well as the structural response of the bridge because the magnitude and gradient of the slab temperature were much lower when the bridge deck served as a solar energy collector.

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Thermal Analysis of the Solar Collector Cum Storage System Using a Hybrid-Nanofluids

Journal of Nanofluids ◽

10.1166/jon.2021.1807 ◽

2021 ◽

Vol 10 (4) ◽

pp. 616-626

Author(s):

Kawthar Dhif ◽

F. Mebarek-Oudina ◽

S. Chouf ◽

H. Vaidya ◽

Ali J. Chamkha

Keyword(s):

Thermal Analysis ◽

Steady State ◽

Solar Collector ◽

Heat Storage ◽

Storage System ◽

Stored Energy ◽

Salt Mixture ◽

Energy Field ◽

Hybrid Nanofluids ◽

Flat Plate Collector

The main problem in the solar energy field is the storage of thermal energy. To divert this problem, it was suggested to use a flat-plat solar collector which also serves as a storage system; this solution will reduce the size of a refrigerating machine that we are studying. A high stored energy density is only possible if we through use latent heat of phase change. Thermal analysis has been developed for this type of storage collector for near-steady state conditions using a nanofluid heat storage substance depended on KNO3–NaNO3 binary salt mixture as PCM and a mix of Al2O3–SiO2 as nanoparticle, from which the new Hottel-Whillier-Bliss equations have been used for efficient flat plate collector. Computations were achieved for a large variety of parameters to verify the significance of the created model.

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Microbiome in an Office Building Using a Cooling Trench as an Outdoor Air Duct

E3S Web of Conferences ◽

10.1051/e3sconf/201911106045 ◽

2019 ◽

Vol 111 ◽

pp. 06045

Author(s):

Mizuki Niimura ◽

U Yanagi

Keyword(s):

Relative Humidity ◽

Energy Saving ◽

Air Temperature ◽

Indoor Air ◽

Principal Coordinate Analysis ◽

Office Building ◽

Metagenomic Analysis ◽

Outdoor Air ◽

Energy Saving Technique ◽

Building Cooling

Subterranean temperature at a depth of 10 m is almost equal to the average outdoor air temperature of the same area. Therefore, if a building cooling trench is used as an outdoor air duct, outdoor air can be cooled in summer and warmed in winter. This energy-saving technique is often used in Japan. However, since the relative humidity in a cooling trench is high, microbe numbers tend to increase in summer. The present study sought to characterize the microbiome status in the cooling trench of such an office building in Japan. Specifically, we performed a metagenomic analysis in which we analyzed DNA directly upon collection from the environment, without intervening cultivation. The results showed the presence of bacteria of the genera Pseudomonas, Lactobacillus, Nesterenkonia, Staphylococcus, Deinococcus, Acinetobacter, Enhydorobacter, and Corynebacterium. Bacteria of the genera Nesterenkonia, Deinococcus, Enhydorobacter, and Corynebacterium predominated on the surface of the trench. Notably, bacteria of the genus Nesterenkonia constituted >50% of the organisms on the surface of the downstream end of the cooling trench. Principal coordinate analysis was used to compare bacterial inhabitants of outdoor air, indoor air from 2nd- and 3rdfloor offices, and the region downstream of the cooling trench. The results suggested that the microbiome of air in this cooling trench influenced indoor air within the building.

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