Heating load reduction characteristics of passive solar buildings in Tibet, China

In this paper, the authors examined the technology to maximize the use of renewable energy. Passive ventilation systems are expected to reduce the energy consumption of the fan and the maintenance burden. In addition, the wall-mounted solar air heater can supply thermal energy without using any energy at all. Therefore, this paper presents a “passive ventilation system with a solar air heater” that combines a passive ventilation system with the solar air heater to preheat the air. This system can reduce the ventilation load. To evaluate the solar air heater performance in a real environment, we developed a simulation for calculating the heat collection capacity of the solar air heater, and then the system was implemented in a real building for verification. The simulation performs hourly unsteady calculations, allowing for accurate evaluation of the annual simulation. Based on the measurement results, the effects of heating load reduction and prediction methods are presented. The solar air heater reduced the monthly ventilation load by up to 50% or more, and by at least 15%. It was also confirmed that there was a high correlation between the actual measurements and the simulation results.

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An Assessment of Heating Load Reduction by Solar Air Heater in Residential Passive Ventilation System

10.20944/preprints202111.0187.v1 ◽

2021 ◽

Author(s):

Junichiro Matsunaga ◽

Koki Kikuta ◽

Hideki Hirakawa ◽

Keita Mizuno ◽

Masaki Tajima ◽

...

Keyword(s):

Energy Consumption ◽

Ventilation System ◽

Prediction Methods ◽

Solar Air Heater ◽

Load Reduction ◽

Air Heater ◽

Air Supply ◽

Measurement Results ◽

Heating Load ◽

Real Building

This paper, we examined the technology to maximize the use of renewable energy. The passive ventilation system is expected to reduce the energy consumption of the fan power and the maintenance burden. In addition, the wall-mounted solar air heater can supply thermal energy without using any energy at all. Therefore, we propose a "passive ventilation system with a solar air heater" that combines a passive ventilation system with solar air heater to preheat the air supply and reduce the ventilation load. To evaluate the solar air heater performance in a real environment, we developed a simulation for calculating the heat collection capacity of the solar air heater, and then implemented the system in a real building for verification. Based on the measurement results, the effects of heating load reduction and prediction methods are presented.

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Study on the Combined Effect of Multiple Passive Energy-Saving Methods for Rural Houses with Cold Alleys

Applied Sciences ◽

10.3390/app11125636 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5636

Author(s):

Xingbo Yao ◽

Shuo Han ◽

Bart Julien Dewancker

Keyword(s):

Energy Saving ◽

Storage Capacity ◽

Heat Storage ◽

Heat Radiation ◽

Load Reduction ◽

Cooling Load ◽

Cold Air ◽

Energy Saving Potential ◽

Heating Load ◽

New System

China’s rural houses are mostly courtyard-style independent houses. Such houses have certain characteristics, e.g., small mutual influences between houses, strong transformation flexibility, and an easier approach to using the natural environment to develop passive energy-saving characteristics. Therefore, rural houses have large energy-saving potential. In this study, for the first time, the cold alleys between buildings were used as an energy source for passive cooling and ventilation. Traditional houses in Shuhe, China, were used as a case study. The cold alleys in the settlements were used to compensate for the natural conditions in summer, and the cold air in the cold alley was introduced into each room using hot-press ventilation and by employing an accumulation effect from a corresponding patio. The room was ventilated and cooled, and air ducts were used to connect the rooms on both sides of the patio to improve the cooling efficiency. The research variables included the existence or non-existence of wall heat radiation (WHR), and the importance and influence of the WHR on the indoor conditions were verified. The cold air trapped in the new system formed an air partition wall, effectively blocking the direct influence of solar radiation on the room, reducing the heat transfer rate of the residential wall, and consuming part of the heat. In winter, based on using air ducts as supporting members, a glass roof was added to the patio, which improved the heat storage capacity of the patio and turned it into a constant-temperature heater for heating the building interior. Based on calculations, in the new system without WHR, the annual cooling load reduction was 55,417.33 kWh. With WHR, the annual cooling load reduction was 28,537.57 kWh. The annual cooling load of the air insulation wall of the new system was reduced to 1133.7 kWh. In winter, using the glass roof to increase the heat storage capacity of the patio reduced the heating load to 54,537.78 kWh.

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Solar Performance of a Dome-Covered House

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.704.431 ◽

2014 ◽

Vol 704 ◽

pp. 431-434

Author(s):

Yao Lin Lin ◽

Wei Yang ◽

Radu Zmeureanu

Keyword(s):

Solar Radiation ◽

Thermal Model ◽

Solar Thermal ◽

Load Reduction ◽

Wall Surface ◽

Annual Average ◽

Sustainable Buildings ◽

Incident Solar Radiation ◽

Heating Load

A dome-covered house is an example of designing sustainable buildings by learning from the optimized biological forms from the nature. This paper presents the solar-thermal model for a transparent dome built above one of the several houses located in Montreal. The incident solar radiation on selected cells, the roof and wall surface are presented. The dome-covered helps to reduce the heating load by 79.3% on January 21st with annual average reduction of 92.9% and if the house is located in Yellowknife, the annual heating load reduction would be 56.3%.

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