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Architects welcome double skin facade (DSF) due to its aesthetic quality. The first DSF structure was intended to prevent cold weather and strong winds. Nowadays, the application of DSF under different climates has been investigated in many previous studies. However, little work had been done on the behaviour of DSF in hot and humid climates. Therefore, this paper aimed to extend the application into this specific climate and Guangzhou was selected as the sample city. Both the climate and the design influence the performance of DSF. In this paper, rather than explore how each design parameter influences the performance, the design was evaluated from an overall aspect. The Designbuilder software was used to build the single skin facade (SSF) and double skin facade base model. Annual HVAC energy consumption for both the two models was calculated and compared. An optimisation process was conducted to figure out what kinds of parameter combination could make the design more energy-saving and thermally comfortable. The results indicated that it was possible to design an energy-saving DSF system applied in hot and humid climates compared with the SSF model. The efficiency of the DSF could be further enhanced with a better parameter combination. The optimised options had some features in common, which could provide some inspirations for the application of DSF in hot and humid climates.

Bees not only produce honey but also provide the main pollination for most crops, while long maturation cycle, low yield of honey and even mass death of bees are observed in traditional hives due to the unfriendly internal thermal condition. In the present paper, a new beehive system integrated with solar thermal/PV system was introduced to optimize the internal thermal condition of the beehive and then to improve the yield and quality of honey. A local bee farm was selected to evaluate the operating performance of the solar beehive in a real natural environment. Comparative filed testing of the solar hive and traditional hive were carried out under different operating modes depending on the weather conditions all the year round. The variation of hive temperature, the quantity of honey collected, Baume degree and the amount of sugar feed consumption were measured and analyzed. The results showed that the air temperature in solar beehive was higher than that in traditional beehive in winter and transition seasons and lower in summer. The quantity of collected honey in the solar beehive was 15.8% more than that in the traditional beehive. The Baume degree indicated that honey can mature 2 days earlier in solar beehive. As to sugar feed consumption in winter, the corresponding quality in solar beehive was lower than that in traditional hive. These results indicated the feasibility of the conjunctive use of solar thermal/photovoltaic technology with the beehive that enlarges the solar energy applications.

It has been a focus to reduce the energy consumption and improve the space heating performance of high-altitude buildings in winter seasons. In view of the abundant solar energy resources of the high-altitude region, the establishment of passive solar houses should be an effective strategy to deal with the problem of thermal comfort. Both window to wall ratio (WWR) and sunspace depth are of vital importance to determine the thermal comfort level of passive solar houses, while there are limited studies on analyzing their impacts on passive solar houses in high-altitude regions. Therefore, this study is designed to examine how WWR and sunspace depth affect space heating of passive solar houses in the Qinghai-Tibetan region. To be specific, the hourly radiation temperature variations and percentages of dissatisfaction of the residential building with different sunspace depth/WWR (including 0.9m/33%, 0.9m/45%, 0.9m/60%, 1.2m/33% and 1.5m/33%) were quantitatively examined. Results indicated that under the condition of 0.9m/45%, the overall average radiation temperature of the building was approximately 16°C during the entire heating season, which could better satisfy the heating requirements. Meanwhile, the average temperature was higher, and the thermal comfort level was better under the ratio of 45% or the depth of 1.5 m, when only an individual factor in either ratio or depth was considered. These findings can provide references for the determination of dimensions of passive solar houses in high-altitude regions.

Energy poverty refers to a situation that people cannot access and use energy safely. It is a major challenge for the global energy system because of its negative impacts on household income, health, education, gender equality and environmental conditions. To solve this problem, many countries advocate the development and promotion of passive solar technology, but the effectiveness of them for energy poverty mitigation has not been evidenced. Therefore, based on empirical studies in the rural areas of Qinghai-Tibet Plateau, this paper aims at investigating the effectiveness of passive solar heating renovation to alleviate energy poverty in rural plateau areas. Specifically, this paper compared and analyzed the coal consumption and indoor air quality during the heating period before and after the renovation of a single-storey building. Further, based on the IES-VE numerical simulation, this paper analyzed the impact of building envelope structure performance on indoor air temperature. The results show that after building renovation, the coal consumption during the heating period could be reduced by 97 kg/week, while the indoor average temperature of two bedrooms were increased by 4.8 °C and 1.7 °C respectively. Setting up the coal stove as an auxiliary heating device, can alleviate the defects of insufficient heating of passive solar energy technology, and indoor temperature could be further improved. However, indoor air quality was lowered because of the high PM2.5 concentration. In contrast, improving envelope performance could further improve the average temperature of two bedrooms and the sunspace to 16.7 °C, 15.9 °C and 15.6 °C, meeting the requirements of indoor space heating. In general, passive solar heating could achieve satisfactory results, but to alleviate energy poverty effectively in rural plateau areas, further attention should be paid to other technical, economic, social and policy issues.

A hybrid solar heating system combining a solar kang subsystem and a solar air heating subsystem for keeping indoor space within thermal comfort level is investigated in this article for the climatic conditions of Qinghai Province (35 °N 96 °E)- China. The main aim of the current research is to study the hybrid heating system's thermal characteristic and the sleeping comfort of occupants in rural buildings. A mathematical model to study the hybrid heating system has been developed and the results have been validated by conducting an experimental study at a building located in Qinghai province. The influence of the different solar thermal collector areas, insulation levels of wall, thermal sensation of the system and different operation strategies have been investigated. It has been observed that the indoor temperature can be improved by up to 6 °C when the ambient temperature is −7.8 °C (average). By changing the solar collector area from 4 m2 to 8 m2, the kang surface average temperature can be improved from 22 °C to 31 °C. Thermal load of sleeping can also remain within acceptable levels when the beddings insulation value is maintained at 4.0clo during night time. It has been observed that without auxiliary power, making the kang system work only at night would be more suitable in the experimental condition.

Energy poverty is prominent in rural Qinghai-Tibet region, China. In sacrifice of thermal comfort and health, residents adaptively choose the biomass fuels and cheap coal for heating and cooking, as an approach to energy expenditure reduction. Considering renewable energy utilization is effective to replace the utilization of conventional fuel, this paper aims to examine the potential of using solar house for energy poverty alleviation. Based on a novel hybrid heating system, we renovated a rural building into a solar house in Wangtun village, Qinghai-Tibet region. The energy consumption and indoor air temperature of the building before and after reconstruction were field measured and comparatively analysed. Results indicate that the energy consumed by solar house with the hybrid heating system was 153.3 kWh/day lower than that by the old building. The average air temperature of the living room and two bedrooms in the solar house reached 12.8°C, 11.0°C and 10.2°C, about 8.78°C, 7.61°C and 6.82°C higher than temperatures of the rooms in the old building. Overall, the solar house has considerably improved indoor environments and provided people with better thermal comfort. It is concluded that solar house can be an effective approach to mitigate domestic energy poverty of the rural Qinghai-Tibet region. The findings may also instruct other rural regions in either China or other developing countries to address the issue of energy poverty.

Solar heating should be recommended strongly for domestic buildings in the Qinghai–Tibetan plateau due to the area's high intensity radiation. In this paper, a novel hybrid solar heating system is presented, that includes a solar kang system, a Trombe wall and a direct gain window. The effects of five combined solar heating operation modes on the indoor hourly temperature for one case domestic building located in the Qinghai–Tibetan plateau were investigated by field measurement and numerical simulation. The optimal operation mode for improving the indoor thermal environment was determined. Furthermore, the effectiveness of each operational mode on the east room was quantitatively evaluated and ranked. The results show that the numerical simulation and field experimental results were well agreed, although there were some differences in specific values. In addition, the results it indicated that a solar kang running all days and Trombe wall running daytime played a significant role in improving the indoor thermal temperature. These relevant findings could provide a reference for solar heating system design and indoor thermal comfort improvement for rural domestic buildings in the Qinghai–Tibetan plateau.

To meet the heating demand in north China and reduce the pollution of traditional Chinese kang, a novel combined heating system consists of solar kang system and solar air heating system is proposed. The solar air system is built for the residents’ daily heating demand. The solar kang system can store the solar energy collected in the daytime and provide a good sleeping environment at night. In this study, demonstration buildings are built in Huzhu, Qinghai province and one of them is chosen to test its thermal performance. Three different operation modes: only the solar air system works, only the solar kang system works and the whole combined system works are tested. A mathematic model of the room and combined system is built based on the demonstrating building. Output simulation results are compared with experiment data. The result shows the combined system can rise the indoor air temperature significantly and the simulation result can fit the experiment well. The indoor air temperature can keep about 18 °C when the ambient average temperature is 5 °C. Kang surface temperature can keep above 26 °C during the night at the same condition. The study proves the excellent heating performance of the combined system.

Due to high efficiency, energy saving, environmental friendliness and safety, the air source heat pump (ASHP) has drawn much attention in the cold and serve cold climate areas of China. In recent years, the Chinese governments further promote the application of air source heat pump in the cold and server area in order to reduce conventional energy consumption and haze occurrence frequency in heating season. The outdoor air temperature is low and fluctuates greatly in these areas, which might lead to unstable running, low efficiency and frequent frost. In this paper, the development direction of ASHP in cold and serve cold was pointed out by analyzing the existing problems of air source heat pump under low temperature condition. These results could provide some references for promotion and application of ASHP in cold and serve cold area like Qinghai province.

Chinese Kang is widely used as heated bed and for heat recovery of cooking stove in Northern China. However there are main drawbacks of indoor and outdoor air pollutant generation and heavy demands on solid fuel handling. A novel combined Kang system, which integrates solar Kang and solar air collector, is here proposed. Experiments were conducted to examine the alternative operating modes: (i) only solar air collector in service, (ii) only solar Kang in service, and (iii) both solar Kang and solar air collector in service. The results show that these three modes behave differently and have distinct effects on room thermal environment in winter. When this pollution-free system operates under the third combined mode, the room temperature increases significantly and the vertical temperature gradient reduces. The Kang surface temperature increases and its uniformity is improved. It is also found that the room air temperature is closely related to the Kang surface temperature. Furthermore, most of the time the thermal environment meets the occupant need. This paper reports the experimental work and investigates into the effects on indoor thermal environment as in rural residences in Northern China.

To promote the application of renewable energy in low-energy buildings in Alpine regions, a solar-air source heat pump (SASHP) system was investigated based on a low-energy residential building in Xining City. First, a solar fresh air (SFA) heating system simulation model was established in TRNSYS software, and the reliability of the model was verified with measured values. In addition, based on the SFA heating system model, a SASHP system model was further realized. The operating characteristics of the SASHP system were explored in depth and compared with those of the single-ASHP system in the heating season. The results show that the SFA heating system model is reliable, with relative errors that can be controlled within 15%. The indoor average temperature (Tave) can be maintained from 16.13 to 19.61 °C. The SASHP system can leads to Tave fluctuations within the range of 21.4–22.9 °C, and the solar fraction can reach 55% in the heating season. Furthermore, the SASHP system can reduce energy consumption by 55.38% compared to the ASHP system; additionally, the COP of the SASHP system is 109.43% higher than that of the ASHP system, and the annual cost is 9.7% lower. Moreover, the SASHP system produces 55.48% less carbon emissions than the ASHP system. These results provide guidance for the application of SASHP systems in Alpine regions.

Low energy buildings are an efficient approach to meet space heating requirements and saving energy. Studies of low energy buildings mainly focus on cold climate regions. However, there is less research on the feasibility of low energy buildings on Qinghai-Tibetan Plateau located in a severely cold climatic region. Therefore, a low energy building equipped with an integrated heating system was built on Qinghai-Tibetan Plateau. The performance of the low energy building was quantitatively evaluated by field measurement and dynamic TRNSYS simulation. To be specific, the indoor temperature and relative humidity were measured, and further served as the data to verify the accuracy of the simulated results. The results show that the temperature and humidity were above 20 °C and 40% in the heating season, in accordance with the regulated low energy building standard (DB63/T1682-2018). According to the TRNSYS simulation, the hourly indoor temperature and relative humidity were generally in the range of 20–24 °C and 34–56%, respectively, in the heating season, with an energy demand of 16.1 kW h/(m2 year). Overall, the building performance meets the local low energy building standard (DB63/T1682-2018). Therefore, a passive building with integrated heating system assistance is feasible for pleasant indoor comfort on Qinghai-Tibetan Plateau. These findings could explore the application potential of low energy buildings in severe cold climate areas.

Passive and active solar heating systems have drawn much attention and are widely used in residence buildings in the Qinghai-Tibetan plateau due to its high radiation intensity. In fact, there is still lack of quantitative evaluation of the passive and active heating effect, especially for residential building in the Qinghai-Tibetan plateau areas. In this study, three kinds of heating strategies, including reference condition, passive solar heating condition and active solar heating condition, were tested in one demonstration residential building. The hourly air temperatures of each room under different conditions were obtained and analyzed. The results show the indoor air temperature in the living room and bedrooms (core zones) was much higher than that of other rooms under both passive and active solar heating conditions. In addition, the heating effect with different strategies for core zones of the building was evaluated by the ratio of indoor and outdoor degree hour, which indicates that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment. The passive solar heating could undertake 49.8% degree hours for heating under an evaluation criterion of 14 °C and the active solar heating could undertake 75% degree hours for heating under evaluation criterion of 18 °C, which indicated that solar heating could effectively reduce the traditional energy consumption and improve the indoor thermal environment in this area. These findings could provide reference for the design and application of solar heating in similar climate areas.

An improved Trombe wall is proposed to adapt to building construction with selective thermo-insulation facades (internal and cavity wall insulation, but not external wall insulation system). The case study is conducted in Xining, Capital city of Qinghai province in China, where the general building facades are mostly selective thermo-insulation facades to fight against the severe cold. A numerical analysis is undertaken to show the effects on the improvement of the building’s thermal environment by comparing the improved Trombe wall system with the classical Trombe wall system. The operating efficiency of the improved Trombe wall can be up to 33.85%, an increase of 56%. The results show that the improved Trombe wall works more effectively than the classical Trombe wall system in utilizing solar energy for the sample building.