Architectural Energy Conservation Research Articles

A Bistable Triboelectric Nanogenerator for Low-Grade Thermal Energy Harvesting and Solar Thermal Energy Conversion.

Converting ubiquitous ambient low-grade thermal energy into electricity is of great significance for tackling the fossil energy shortage and environmental crisis but poses a considerable challenge. Here, a novel thermal-driven triboelectric nanogenerator (TD-TENG) is developed, which utilizes a bimetallic beam with a bi-stable dynamic feature to induce continuous mechanical oscillations, and the mechanical motion is then converted into electric power using a contact-separation TENG. The thermal process inside the device is systematically investigated and effective thermal management is conducted accordingly. After optimization, the TD-TENG can produce a power density of 323.9mWm-2 at 59.5°C, obtaining the highest record of TENG-based thermal energy harvesters. Besides, the first prototype of TENG-based solar thermal harvester is successfully demonstrated, with a power density of 364.4mWm-2 . Moreover, the TD-TENG can harvest and dissipate the heat at the same time, exhibiting great potential in over-heated electronics protection as well as architectural energy conservation. Most importantly, the operation temperature range of the TD-TENG is tunable by adjusting the bimetal parameters, allowing the device a wide and flexible working thermal gradient. These unique properties validate the TD-TENG is a simple, feasible, cost-effective, and high-efficient low-grade thermal energy harvester.

Photoinitiator-loaded mesoporous polystyrene-divinylbenzene microspheres driven broadband reflection in polymer stabilized cholesteric liquid crystals

The broadband reflection polymer stabilized cholesteric liquid crystal (PSCLC) films have been fabricated by introducing the photoinitiator-loaded mesoporous polystyrene-divinylbenzene microspheres. By adjusting the UV intensity and the polymerization temperature, the polymerization process and diffusion process can be controlled to regulate the non-uniform pitch distribution. The regional differences of polymerization rate caused by the dissolved photoinitiator under UV irradiation would result in the diffusion of polymerizable monomer, which drove the chiral dopant to diffuse in opposite direction. The uneven chiral dopant concentration caused the non-uniform pitch distribution. Meanwhile, the non-uniform pitch distribution was frozen by the polymer networks. The reflection bandwidth was broadened from 260 nm to 565 nm in the near infrared region. The simple method for the preparation of broadband reflective PSCLC films is expected to be used in the fields like architectural energy conservation or infrared shield.

Broadband reflective liquid crystal films induced by facile temperature-dependent coexistence of chiral nematic and TGB phase

ABSTRACTA wide pitch gradient covering the near infrared region (750.0–2500.0 nm) were facilely obtained by simple controlling temperature difference to LC mixtures with a twist grain boundary (TGB)–N* phase transition. After the pitch gradient formed, the structure of broad reflective bandwidth was fixed through polymerisation of monomers in mixtures by UV irradiation. It was found that the temperature difference between the up and down side of the samples was critical to form wide-pitch gradient distribution. Additionally, the reflection wavelength and bandwidth of films could be adjusted by the applied temperature difference with the widest bandwidth up to 1750 nm. This simple method for the preparation of broad reflective films was expected to be used in the fields like architectural energy conservation or infrared shield.

Polymeric infrared reflective thin films with ultra-broad bandwidth

ABSTRACTA polymeric liquid crystalline film was fabricated by photo-induced diffusion and mesogenic phase structural transition of photopolymerisable acrylate monomer mixtures that presented phase transition between cholesteric (Ch) and smectic (SmA) phases. By controlling the curing temperature to be close to SmA–Ch phase transition, a novel architecture that combined Ch and SmA-like short-range ordering (SSO) nanostructures was obtained, which reflected light with the wavelength from 0.5 to 11.5 µm. Experimental results showed that the existence of UV-absorbing dye and curing temperature were critical for the creation of asymmetrical super wide pitch gradient distribution. Moreover, the reflection wavelength and bandwidth of the cholesteric liquid crystal (CLC) films were tuneable by adjusting proportion of the compounds, and the bandwidth could be broadened up to 13 μm. It was expected to have great potential applications in fields like architectural energy conservation or infrared-stealth.

Applications of Rigid Polyurethane Foam Insulation Materials in Architectural Energy Conservation

This paper briefly introduces the main properties and four systems of rigid polyurethane thermal insulation foam intended for use in buildings for energy conservation purposes, and application development at home and abroad. Although the applications of polyurethane are widespread in architectural energy conservation, there are some problems just as high price, smoke toxicity, fire safety and so on thus it still occupies a small proportion in buildings for energy conservation purposes. It is no doubt that the function with high efficiency of thermal insulation, fireproof and low smoke density of rigid polyurethane foam conservation products is our goal.

Passive Energy-Saving Design in Hot and Humidity Area: A Case Study of Multi-Functional Stadium of Guangdong College of Pharmacy

As stadiums have high energy consumption in architectural lighting and air conditioning, how to make full use of natural lighting and natural ventilation is the key to architectural energy conservation. To this end, many passive energy conservation measures have been taken into account in designing Multifunctional Stadium of Guangdong Pharmaceutical University. For instance, strip light windows with vertical shading have been installed on east and west facade, open external windows on south and north facade etc. Test result of the Stadium shows that the above-mentioned passive design methods are able to increase natural light intensity of the playing field and prevent glare, improve wind velocity of natural ventilation and comfort in spectator areas.

Design of the Low-Carbon and Ecological Kindergarten

The public in China have a vague notion of architecture energy conservation, additionally the various and complex geographical position and climate, so the problem of architectural energy dissipation has deteriorated. In terms of architectural energy conservation, this design wholly considered energy conservation and emission reduction in the whole life cycle. The theory of “nonexistence-existence-nonexistence” should be carried out practically and low-carbon, ecological kindergarten will be founded in Huainan by studying and taking advantage all kinds of reasonable energy conservation technology. We should exert a subtle influence on cultivating children’s sense of energy conservation and emission reduction in order to make it be popular in the society which treats children as center.

Measurement and Analysis of Multi-Functional Stadium of Guangdong College of Pharmacy

As stadiums have high energy consumption in architectural lighting and air conditioning, how to make full use of natural lighting and natural ventilation is the key to architectural energy conservation. To this end, many passive energy conservation measures have been taken into account in designing Multifunctional Stadium of Guangdong Pharmaceutical University. For instance, strip light windows with vertical shading have been installed on east and west facade, open external windows on south and north facade, and green roof on Auxiliary Stadium etc. Test result of the Stadium shows that the above-mentioned passive design methods are able to increase natural light intensity of the playing field and prevent glare, improve wind velocity of natural ventilation and comfort in spectator areas, reduce inner surface temperature and thermal radiation of the roof on Auxiliary Stadium.