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Phase Change Materials (PCM's) are characterised by a large thermal capacity and by melting temperatures close to those associated with human comfort. Thanks to the "artificial inertia" they can give a building, they can be used in components such as wallboards, floors, etc. in order to: -store free heat gains during winter days and release energy...
Citations
... Thermal capacity and perhaps thermal mass describes the capability of the construction framework to possibly engross a lot of high heat through the day so as to release them throughout nighttime [66,67]. With this particular thermal inertia, unexpected interior climate modifications have been stayed away from [68,69]. ...
An energy crisis has become a challenging issue all over the world. More than 40% of energy consumption (or more than that) is due to buildings. People were and are always looking to improve indoor conditions. Cold countries are worried about keeping the space warm whereas hot countries are worried about keeping the space cooler. There has been an exceptional increment in the utilization of air conditioning system, air coolers and fans for cooling the buildings all around the globe. The cooling load requirements of buildings have witnessed a severe energy crisis in developing countries, particularly during summer for the last two decades. Increasing consumption of energy is also one of the reasons and has led to environmental pollution resulting in global warming and ozone layer depletion. To overcome the above-said problem, we have to go with different types of cooling systems. Passive cooling and Active cooling are the two main types of cooling systems. In Active cooling technique mechanical energy in one or other form is used to cool the interior of the building (ex: Air-Conditioning (A/C), Ceiling fans etc.) which requires power source to provide the desired effect, whereas, Passive cooling technique is natural method of cooling buildings is least expensive, and it mainly depends on interaction of building and its surrounding. This paper aims to present a review of different types of Passive cooling technologies to reduce the cooling load on buildings.
... Building thermal capacity. Thermal capacity, or thermal mass, refers to the ability of the building structure to potentially absorb large amounts of heat through daytime in order to release them during night [107,108]. With this thermal inertia, sudden indoor temperature changes can be avoided [109,110]. ...
In this document a review of three active as well as ten passive cooling methods suitable for residential buildings is carried out. The review firstly addresses how the various technologies cool the space according to the terms of the building heat balance, under what technical conditions they might be applied, and what their energy needs are. Secondly, what scientific analysis has been carried out and what the major findings are. Thirdly, what their economic and technical feasibility of use at the stage of implementation and operation within a dwelling are. Then, either with the reviewed studies or with a simulation modelling, an assessment of temperature drop of each cooling method within a standard-size dwelling is carried out. Also, a comparison of initial investment, energy consumption, maintenance, retrofitting and required space is done. Thereafter, with this information, a decision-making program is developed in order to find out the most suitable cooling method of this dwelling in each case study according to the climate, status (new or existing), and the affordability. With that, and taking the Mexican housing sector as case study, it is found that building color, shading system, night ventilation, controlled ventilation, roof coating and eco-evaporative cooling are the most suitable passive methods for an extensive use in this country.
... Small amounts of PCMs can have the effect of large amounts of conventional thermal mass with the added advantages of being light and having a shaper temperature change. PCMs may also be able to shift the time of the peak temperature and diminish space temperature swings broadening the exploitation of solar radiation in the space, as seen in a number of published works [4][5][6][7][8][9][10][11][12][13][14][15]. However, there are limitations to be considered such as: † The PCM needs to be in contact with hot and cold air alternatively for acquiring and discharging heat (and consequently melting and solidifying), so it relies heavily on the design of openings, an effective indoor ventilation strategy and informed users. ...
The energy expended for conditioning buildings around the world is worryingly large and increasing every year. Currently,
almost half of houses around the world use some type of energy-expensive conventional air-conditioning system. These systems
are high emitters of gases such as carbon dioxide and so high contributors to climate change. Consequently, alternatives must
be considered. Earth–air heat exchangers (EAHEs) and phase-change materials (PCMs) may be options; they have, however, limitations.
This paper proposes a novel hybrid space-conditioning system combining EAHEs with PCMs, which uses surfaces as sources of
heating or cooling to provide better temperature distribution across a space and comfort enhancement with low energy use.
The idea is to use an EAHE to provide cool air to discharge the PCM, consequently helping to overcome most of the limitations
of both strategies. Two of a series of experiments undertaken to test the proposed system are reported in this article. The
EAHE + PCM system compared with a reference room could decrease temperature swings by up to 47%. The system was proved to
work although further work is required to make it commercially viable.
