Search

• An air conditioning system with thermoelectric modules is analysed and optimised. • Cooling investment and operating costs are discussed. • Heat exchangers are optimised based on economic indicators. • The economically optimised air conditioning system can be significantly overloaded. • TEC air conditioning is expensive but quiet, compact and environmentally friendly. The paper presents simulations of an air conditioning system based on thermoelectric modules. The proposed system is of a very simple structure, easy to control, scalable, noiseless, and harmless to the environment. The most important parameters that were to be changed were the number of modules, the electric current, and the size of the heat exchangers. The analyses were carried out for a commercially available thermoelectric module whose parameters were determined experimentally. The air conditioning system was analysed in terms of its cooling capacity and COP. Furthermore, it was optimized with economic criteria to achieve the highest cooling capacity of 1 dollar of total cost (electricity and investment) in a set period of device lifetime (ETCC – economic total cooling capacity). For 2400 h of device operation, at a temperature difference of 5 K and the average electricity cost in the EU, the optimized ETCC totals about 0.58 W/$. With the possibility of altering the inner geometry of the thermoelectric modules, the factor increased to 0.64 W/$. The test results showed that the device optimized in terms of ETCC did not operate with maximum cooling power and could be overloaded by about 30% in the reference working conditions. [ABSTRACT FROM AUTHOR]

Phase change materials (PCM) are known as an effective technology to store larger amounts of thermal energy per unit mass than conventional thermal mass building materials such as concrete and stone. They add thermal stability to lightweight constructions without adding physical mass. This paper presents a method to assess the effect of PCMs on thermal comfort and energy consumption in UK dwellings in summer months. A methodology is presented to assess the impact of climate change temperature increases in the UK by considering current, 2020, 2050 and 2080 weather scenarios using the dynamic thermal simulation software DesignBuilder, which employs EnergyPlus as its calculation engine. The study used simulations of a high performance detached house model with a near Passivhaus standard in London, where the impact of climate change effect is predicted to be significant. It was shown that appropriate levels of PCM, with a suitable incorporation mechanism in to the building construction, has significant advantages for residential buildings in terms of reducing total discomfort hours and cooling energy loads. [ABSTRACT FROM AUTHOR]

Abstract: Hainan province is the only tropical and island province in China, with the unique climatic and geographical features. It has a different energy performance in public buildings from those in the inland areas. This paper investigated the current situation of energy consumption of the sampled public buildings, including 26 hotels, 24 office buildings and 7 department stores, through analyzing utility billing data, on-site survey and measurement, and site operational records. The breakdowns of energy consumption found out that the electricity dominated the energy consumption for all the sampled buildings and the air conditioning system played a key role in the energy consumption of major building services. By analyzing the main factors for building energy consumption, the annual average energy use indexes were calculated to be 141.63kWh/m2, 87.70kWh/m2, and 166.95kWh/m2 for hotels, office buildings and department stores, respectively. Besides, the comparison between Hainan province and other areas revealed that the building energy consumption of this tropical province was at a low level. Because indoor environment quality can influence the health and work efficiency of humans in buildings, field tests on the indoor environment quality were also carried out, and the performance of indoor environment quality was rated. [Copyright &y& Elsevier]