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At present, air conditioning (AC) is the most effective means for the cooling of indoor space. However, its increased global use is problematic for various reasons. This paper explores the challenges linked to increased AC use and discusses more sustainable alternatives. A literature review was conducted applying a transdisciplinary approach. It was further complemented by examples from cities in hot climates. To analyse the findings, an analytical framework was developed which considers four societal levels—individual, community, city, and national. The main challenges identified from the literature review are as follows: environmental, organisational, socio-economical, biophysical and behavioural. The paper also identifies several measures that could be taken to reduce the fast growth of AC use. However, due to the complex nature of the problem, there is no single solution to provide sustainable cooling. Alternative solutions were categorised in three broad categories: climate-sensitive urban planning and building design, alternative cooling technologies, and climate-sensitive attitudes and behaviour. The main findings concern the problems arising from leaving the responsibility to come up with cooling solutions entirely to the individual, and how different societal levels can work towards more sustainable cooling options. It is concluded that there is a need for a more holistic view both when it comes to combining various solutions as well as involving various levels in society. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of prenatal exposure to extreme temperatures on birth outcomes—specifically, the log of birth weight and an indicator for low birth weight—using a nationally representative dataset on rural China. During the time period we examine (1991–2000), indoor air conditioning was not widely available and migration was limited, allowing us to address identification issues endemic in the climate change literature related to adaptation and location sorting. We find substantial heterogeneity in the effects of extreme temperature exposure on birth outcomes. In particular, prenatal exposure to heat waves has stronger negative effects than exposure to cold spells on surviving births. [ABSTRACT FROM AUTHOR]

The development of climate-friendly technologies and its diffusion across countries is of key importance to slow climate change. This paper considers technologies in the mobile air-conditioning (MAC) sector which is a major contributor of fluorinated greenhouse gas emissions. Using patents as an indicator of innovations and patent citations as a proxy for knowledge flows, the inducement of new environmental and non-environmental technologies and knowledge diffusion within and across countries are analysed. The focus is on direct abatement of fluorinated greenhouse gases excluding energy efficiency improvements. We find that most environmental MAC patents originate from the US and Germany. Most knowledge flows take place within countries. Regarding cross-country flows most environmental knowledge diffuses from French and German patents, which is likely to be a result of regulatory activities in Europe and intensified research on environmentally benign MAC systems. Yet, this exchange of knowledge is not very intensive and stable so that the impact of EU regulations on US and Japanese patenting behaviour seems to be fairly weak. [ABSTRACT FROM AUTHOR]

The foremost role of a building is to assure the comfort of its occupants. The thermal comfort of a building depends on the outdoor climate and requires a demand in energy for heating and cooling. In this paper, demand of energy (heating/cooling) in the buildings is discussed in Douala, Cameroon. Daily data of the last 40 years coming from five weather stations of Cameroon have been studied. Some forecasts have been carried out with 14 GCM models, associated to three future climate scenarios B1, A2, and A1B. However, only INCM3 of General Circulation Model (GCM) and A2 scenario was used. Energy demand in buildings is valued by HDD (heating degree day) and CDD (cooling degree day) indices. Obtained results show that the temperature evolves more quickly in dry season than in rainy season in Douala. Climate rise indicates an increasing demand of energy in the buildings for cooling. Global Douala heating shows a definite effect on outdoor comfort. From 2045 to 2075, the demand of energy for cooling will be superior to 50%. The total demand in energy for heating in the buildings is estimated to be 67.882 kcal from 1970 to 2000 and will be around 67.774 kcal from 2013 to 2043. [ABSTRACT FROM AUTHOR]

Energy consumption is a chief contributor to climate change, which increases as households use more air conditioning (AC) in response to climate change. As such, climate change–induced energy consumption is expected to increase more drastically in fast-emerging economies, where the rapidly increasing household income and urbanization promote the large-scale adoption of ACs. Based on data on daily household electricity consumption in the Zhejiang Province of China, this study estimates the household temperature response functions. In particular, we consider urban and rural households with and without AC to chart their various cooling demand and consumption behavior, typically indicated by U-shaped temperature-response functions. Compared to rural households and those without AC, urban households and those with AC exhibit steeper response functions at both high and low temperatures. Based on these estimates, we simulate the household electricity consumption under climate change scenarios RCP4.5 and RCP8.5. The simulation results reveal that (1) under constant urbanization and AC adoption rates, the electricity consumption in the residential sector will increase by 5.04–16.37% because of climate change; (2) as the AC adoption rate increases from 82.50 to 95.00% in urban areas and from 74.40 to 85.00% in rural areas, the household electricity consumption in Zhejiang Province will further increase by 0.52–1.05%; (3) combined with the increase of urbanization from 68.73 to 80.00%, the increase rate of annual electricity consumption of the residential sector will further rise to 25.60–55.79%. These findings highlight the vicious cycle of climate change and cooling along with the challenges encountered by electricity grids. [ABSTRACT FROM AUTHOR]

Rising ambient temperatures due to climate change will increase urban populations' exposures to extreme heat. During hot hours, a key protective adaptation is increased air conditioning and associated consumption of electricity for cooling. But during cold hours, milder temperatures have the offsetting effect of reducing consumption of electricity and other fuels for heating. We elucidate the net consequences of these opposing effects in 36 cities in different world regions. We couple reduced-form statistical models of cities' hourly responses of electric load to temperature with temporally downscaled projections of temperatures simulated by 21 global climate models (GCMs), projecting the effects of warming on the demand for electricity circa 2050. Cities' responses, temperature exposures and impacts are heterogeneous, with changes in total annual consumption ranging from - 2.7 to 5.7%, and peak power demand increasing by as much as 9.5% at the multi-GCM median. The largest increases are concentrated in more economically developed mid-latitude cities, with less developed urban areas in the tropics exhibiting relatively small changes. The results highlight the important role of the structure of electricity demand: large temperature increases in tropical cities are offset by their inelastic responses, which can be attributed to lower air-conditioning penetration. [ABSTRACT FROM AUTHOR]

An assessment of the overall impact of the observed and expected climatic changes on energy production, distribution, and consumption in Russia is presented. Climate model results of various complexity and evaluation data on the vulnerability of various energy production sectors to climate change are presented. It is shown that, due to the increase of air temperature, the efficiency of electricity production at thermal and nuclear power plants declines. According to the climate model results, the production of electricity at TPPs and NPPs by 2050 could be reduced by 6 billion kW h due to the temperature increase. At the same time, as a result of simulation, the expected increase in the rainfall amount and river runoff in Russia by 2050 could lead to an increase in the output of HPP by 4-6% as compared with the current level, i.e., by 8 billion kW h. For energy transmission and distribution, the climate warming will mean an increase in transmission losses, which, according to estimates, may amount to approximately 1 billion kW h by 2050. The increase of air temperature in summer will require higher energy consumption for air conditioning, which will increase by approximately 6 billion kW h by 2050. However, in total, the optimal energy consumption in Russia, corresponding to the postindustrial level, will decrease by 2050 by approximately 150 billion kW h as a result of climate- induced changes. The maximum global warming impact is focused on the heat demand sector. As a result of a decrease in the heating degree-days by 2050, the need for space heating is expected to fall by 10-15%, which will cause a fuel conservation sufficient for generating approximately 140 billion kW h of electricity. Hence, a conclusion about the positive direct impact of climate change on the Russia’s energy sector follows, which is constituted in the additional available energy resource of approximately 300 billion kW h per year. [ABSTRACT FROM AUTHOR]

The aim of this work is to assess the use of mixed-mode ventilation for a typical office building in Lebanon and consequently reduce Heating Ventilation and Air Conditioning (HVAC) energy consumption in the observed current and under the future projected climatic conditions. Mixed-mode cooling is considered a compromise between the insufficient natural ventilation and the expensive year round-operated HVAC. A control algorithm is set for windows and HVAC system to ensure mixed-mode operation. Dynamic simulations are performed on a typical office building in Beirut City under the mixed-mode operation in the present and the future using commercial IES-VE software. The results of the software were validated against measured HVAC and total energy consumption of the typical office base case with conventional mechanical system. The results of the simulations are evaluated in terms of potential reduction in energy consumption under the present and the future weather data. Finally, a lifecycle cost analysis is performed for the proposed system, and its payback period is computed. Under present construction practices and weather data, 31% annual energy savings were achieved using mixed-mode system. Under future 2050s projected weather data, annual energy savings of 21% was attained with a payback period of 3.8 years. [ABSTRACT FROM AUTHOR]

This study describes the first use of concurrent high-precision temperature and drip rate monitoring to explore what controls the temperature of speleothem forming drip water. Two contrasting sites, one with fast transient and one with slow constant dripping, in a temperate semi-arid location (Wellington, NSW, Australia), exhibit drip water temperatures which deviate significantly from the cave air temperature. We confirm the hypothesis that evaporative cooling is the dominant, but so far unattributed, control causing significant disequilibrium between drip water and host rock/air temperatures. The amount of cooling is dependent on the drip rate, relative humidity and ventilation. Our results have implications for the interpretation of temperature-sensitive, speleothem climate proxies such as δ18O, cave microecology and the use of heat as a tracer in karst. Understanding the processes controlling the temperature of speleothem-forming cave drip waters is vital for assessing the reliability of such deposits as archives of climate change. [ABSTRACT FROM AUTHOR]