Page - 4 - in options, Volume summer 2019

News in brief A cool indoor space on a sweltering summer day is an expensive luxury in many parts of the world: only 8% of the 2.8 billion people living in the world’s hottest regions have an air conditioning unit. In addition, more than one billion people lack access to electricity and at least one billion live in slum conditions, making access to space cooling challenging. IIASA researchers compared residential cooling needs and access to air conditioning for countries in the Global South to determine the location of populations potentially exposed to heat stress. The results revealed large gaps in access to essential space cooling, especially in India, South-East Asia, and sub-Saharan Africa. The study gives a first estimation of the energy required to fill this gap. Providing air conditioning for all who need it would require an increase in energy consumption of 14% of current global residential electricity consumption. Since air conditioning units however tend to use a lot of energy, the researchers point out that increased air conditioning access could come with high costs and environmental impacts, unless equal attention is paid to energy efficiency and building design. IIASA researcher Alessio Mastrucci led the study. He says, “Filling the cooling energy poverty gap requires integrated strategies beyond providing access to affordable, efficient, and low-emitting air- conditioning. Access to electricity and affordable, energy efficient homes is of critical importance in this respect.” Extreme temperatures bring greater mortality risk to people living in China’s rural communities than in urban areas, according to IIASA research. The disparity between urban and rural mortality risk was found across the entire population, but was greater for women than men, and for people over 65. The researchers used six years of detailed weather, air pollution, population density, and mortality data from Zheijiang Province to estimate the numbers of urban and rural deaths attributable to hot and cold temperatures. The findings suggest that by omitting important differences between rural and urban areas and populations, previous studies may have underestimated the overall impact of extreme temperatures on population mortality. “These findings go against the assumption that urban residents are at higher risk due to the urban heat island effect, which raises temperatures in cities compared to surrounding areas,” says IIASA researcher Stefan Hochrainer-Stigler, a coauthor of the study led by 2016 Young Scientists Summer Program participant Kejia Hu in collaboration with other researchers in China and at IIASA. IIASA researcher and coauthor Wei Liu says, “While fast urbanization is taking place, in the developing world there is still a large percentage of population living in rural areas. They are more likely to be working long days outdoors and also to have poor public health system coverage. Both these factors lead to greater vulnerability.” Cooling needs in the Global South Further info: Hu K, Guo Y, Hochrainer-Stigler S, Liu W, See L, Yang X, Zhong J, Fei F, et al. (2019). Evidence for Urban–Rural Disparity in Temperature–Mortality Relationships in Zhejiang Province, China. Environmental Health Perspectives 127 (3): e037001. [pure.iiasa.ac.at/15773] Stefan Hochrainer-Stigler: hochrainer@iiasa.ac.at Further info: Mastrucci A, Byers E, Pachauri S, Rao ND (2019). Improving the SDG energy poverty targets: residential cooling needs in the Global South. Energy & Buildings 186: 405-415 [pure.iiasa.ac.at/15739] Alessio Mastrucci: mastrucc@iiasa.ac.at Extreme temperatures hit rural residents harder www.iiasa.ac.at4 Options Summer 2019