scholarly journals Energy Saving Potential of Radiant Floor Heating Assisted by an Air Source Heat Pump in Residential Buildings

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1321
Author(s):  
Yu-Jin Hwang ◽  
Jae-Weon Jeong

The objective of this research is to establish an appropriate operating strategy for a radiant floor heating system that additionally has an air source heat pump for providing convective air heating separately, leading to heating energy saving and thermal comfort in residential buildings. To determine the appropriate optimal operating ratio of each system taking charge of combined heating systems, the energy consumption of the entire system was drawn, and the adaptive floor surface temperature was reviewed based on international standards and literature on thermal comfort. For processing heating loads with radiant floor heating and air source heating systems, the heating capacity of radiant floor heating by 1 °C variation in floor temperature was calculated, and the remaining heating load was handled by the heating capacity of the convective air heating heat pump. Consequently, when the floor temperature was 25 °C, all heating loads were removed by radiant floor heating only. When handling all heating loads with the heat pump, 59.2% less energy was used compared with radiant floor heating only. Considering the local discomfort of the soles of the feet, the floor temperature is expected to be suitable at 22–23 °C, and 31.5–37.6% energy saving compared with those of radiant floor heating alone were confirmed.

Author(s):  
C. C. Ngo ◽  
B. A. Alhabeeb ◽  
M. Balestrieri

Radiant floor heating systems have become popular due to their advantages over conventional heating systems in residential, commercial and industrial spaces. They are also used for snow and ice melting and turf conditioning applications. This paper presents a general study focuses on the design of radiant floor heating systems and investigates the effect of design parameters such as pipe spacing (ranging from 4 in. to 12 in.), pipe depth (ranging from 2.5 in. to 6.5 in.) and pipe temperature (45 °C, 65 °C and 85 °C) on the performance of radiant floor heating system embedded in different mediums (air, gravel and sand). The experimental results showed that a radiant heating system with pipes embedded at a shallow burial depth and placed closer together resulted with a more desired floor temperature distribution. The average floor temperature was also higher when the piping system was embedded in an air-filled space instead of a porous medium such as gravel or sand.


2019 ◽  
Vol 11 (14) ◽  
pp. 3926 ◽  
Author(s):  
Gyuhwan Yeom ◽  
Dong Eun Jung ◽  
Sung Lok Do

The number of domestic apartment houses in South Korea that use district heating is steadily increasing. In addition, most Korean residential buildings use radiant floor heating systems. For such systems, the heating water temperature supplied by a heat exchanger in a mechanical room serves as one of the critical control parameters for providing heat to individual residential apartments. Fixed temperature (FT) and outdoor temperature reset control (OTR) have conventionally been used to adjust the heating supply water temperature. However, both control methods have a major technical weakness; they do not reflect changes in residents’ heating use. To overcome this issue, this study proposes a new method for controlling the heating supply water temperature, called Residential Energy Demand (RED). To verify the proposed method, researchers conducted both simulation- and experiment-based tests. The RED control method achieved about 4% reduction in heating energy consumption compared to the conventional OTR control process. In addition, the RED control method increased the average indoor temperature by 0.17 °C during the heating period. Therefore, this study demonstrates that the proposed control method is capable of achieving energy savings and a warmer thermal indoor environment.


2020 ◽  
Vol 36 (5) ◽  
pp. 619-628
Author(s):  
Wanying Zhao ◽  
Meizhi Wang ◽  
Hao Li ◽  
Guoming Li ◽  
Zhengxiang Shi

HighlightsAn old nursery pig building was retrofitted to potentially improve envelope insulation capacity.A mathematical theory based on coal consumption was established to evaluate energy efficiency of insulation renovation for a nursery pig building.The heat loss of the nursery pig house with 90-mm-thick extruded polystyrene boards was 60% lower than that without the materials.Ground source heat pump and air source heat pump are economical and environmental-friendly heating systems.Abstract. Appropriate renovation of old buildings is critical for energy-efficient pig production. Currently, energy consumption, especially coal consumption, keeps on rising in the production. Therefore, it is essential to develop energy-saving renovation methods for old nursery pig buildings and use cleaner heating energies. A mathematical theory based on coal consumption was established to evaluate energy efficiency of insulation renovation. Two nursery pig houses were tested in this experiment. One was the retrofitted house with the 90-mm-thick extruded polystyrene boards embedded onto outer walls, and the other one was served as a control house without those insulation materials. The results show that the air temperature and inside surface temperature of the retrofitted house were significantly higher than those of the control house in winter. Therefore, though adding insulation layers to walls, the envelope insulation capacity was improved. Meanwhile, the heat loss of the retrofitted house was 60% lower than that of the control house (11.08 W m-2 vs. 27.93 W m-2), when the theoretical ventilation rate was 1560 m3 h-1. In addition, with the prohibition of the coal usage in forseeable future of China, the ground source heat pump and air source heat pump can be economical solutions for heating systems with clean and renewable energy. Keywords: Air source heat pump, Extruded polystyrene board, Ground source heat pump, Heating, Thermal insulation.


2012 ◽  
Vol 12 (6) ◽  
pp. 1398-1408 ◽  
Author(s):  
Sun Sook Kim ◽  
Dong Hwa Kang ◽  
Dong Hee Choi ◽  
Myoung Souk Yeo ◽  
Kwang Woo Kim

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4594 ◽  
Author(s):  
Chenxiao Zheng ◽  
Shijun You ◽  
Huan Zhang ◽  
Zeqin Liu ◽  
Wandong Zheng ◽  
...  

Traditional defrosting methods applied to solve frosting problems of air-source heat pumps operating in cold periods may reduce heat capacity of the system and decrease indoor thermal comfort. In order to improve the performance of air-source heat pump (ASHP) and maintain indoor temperature in defrosting conditions, an air-source heat pump combined with a refrigerant direct-condensation radiant floor heating system with phase change material is proposed and evaluated in this study. Two radiant floor heating terminals with and without composite phase change material modules were compared through experiments. A composite phase change material based on dodecanoic acid-tetradecanol-hexadecanol mixture and expanded graphite was investigated for this application. Experimental results indicate that both heat fluxes of two comparing terminals are higher than 70 W/m2 in heating condition. At the same time, the floor surface temperature, indoor air temperature, and heating capacity of the terminal with composite phase change material modules are higher than those without composite phase change material modules in defrosting condition. This suggests that the proposed system with composite phase change material modules can improve indoor thermal comfort in defrosting condition as well as satisfy the heating requirement in heating condition.


2012 ◽  
Vol 608-609 ◽  
pp. 969-973
Author(s):  
Dong Zhang ◽  
Xiao Dong Zhou ◽  
Lin Jun Wang ◽  
Qin Tong Zhao ◽  
Tao Min Wei

A multiple energy assisted heat pump (MEAHP) system for radiant floor heating was proposed, which integrated a domestic air-assisted heat pump with a solar water heater. The system mainly employed a vacuum tube solar collector with a surface area of 7.44 m2, an electrical rotary-type hermetic compressor, two capillary tubes and three heat exchangers. All operation modes have functioned successfully in Lanzhou city, China. The experimental data of air-source heat pump (Mode 2) and double-source heat pump (Mode 3) have been discussed. The results show that the coefficient of performance (COP) of the MEAHP system and the COP of the space heating system (COPs) are around 2.2 and 1.9 with the room air at 19 °C, respectively, and the temperature difference of the inlet and outlet of the radiant floor heating pipes is 2.8 °C. Some methods to improve the system performance are put forward.


Sign in / Sign up

Export Citation Format

Share Document