Heat reduces productivity, even in factories with air conditioning

The study, led by the University of Exeter, monitored the relationship between outdoor temperatures and worker productivity at a Chinese high-tech factory. Despite the factory's climate-controlled conditions, its output decreased by 0.83% for every 1°C increase in outdoor temperature.

The research team discovered that nighttime heat (which can interfere with sleep) contributed to a portion of the decline in productivity; however, daytime heat affected productivity even after cool nights. It is unclear why this occurs, but the researchers say their findings should serve as a "cautionary tale" as governments and corporations adapt to rising global temperatures.

Dr. Jingnan Chen of the University of Exeter remarked, "We typically consider climate change in terms of its large-scale effects, but it also affects individuals. Previous research has demonstrated, not surprisingly, that working outdoors or in buildings without air conditioning reduces productivity. Our findings, which indicate that heat affects workers even in climate-controlled factories, provide additional evidence of the probable economic effects of climate change."

Dr Miguel Fonseca added: "Policymakers and business leaders might assume that technology such a climate-controlled buildings can mitigate the effects of climate change. In our study, climate control alone was insufficient to protect a company from the adverse effects of high outdoor temperatures."

The study utilised data on the daily maximum "wet bulb" temperature, which accounts for both heat and humidity.

This information was combined with individual-level data on the quantity and quality of work performed in 35,190 worker-shifts (635 distinct male workers). The factory analysed in the report manufactures silicon wafers, a crucial component of solar panels.

Due to the delicate nature of the wafers, all workshops are equipped with climate-control systems that maintain a constant temperature of 25°C (77F) and relative humidity of 60% to ensure product quality.

The 0.83% decrease in productivity for each 1°C increase in temperature resulted in a decrease of 22,6 to 33,4 wafers per worker. A wet-bulb temperature above 28°C was associated with a 5.8% decrease in productivity compared to an average day, according to the study.

Journal Reference: Jingnan Chen, Miguel A. Fonseca, Anthony Heyes, Jie Yang, Xiaohui Zhang. How Much Will Climate Change Reduce Productivity in a High-Technology Supply Chain? Evidence from Silicon Wafer Manufacturing. Environmental and Resource Economics, 2023; DOI: 10.1007/s10640-023-00803-4