Climate change could cause BLACKOUTS in US due to increase in summer air conditioning, study warnsÂ
will drive an increase in the number of homes and businesses running air conditioning through the summer in the US, according to a new study. This could result in prolonged blackouts during peak times, if more is not done to increase power capacity and improve efficiency of power plants, according to research carried out by the American Geophysical Union in Washington, . To better understand the impact of climate change on air conditioning use, the researchers projected summertime usage against different levels of warming. For example, if temperatures rise by 2.7F over pre-industrial levels - a target set by the UN to limit the worst of climate change - demand would still outstrip capacity by as much as 8 per cent, the researchers revealed. If temperatures rise by 3.6 degrees Fahrenheit, a more likely outcome based on current trends, then demand would be 13 per cent higher than production capacity. The team say improvements in the efficiency of home air conditioning appliances by up to 8 per cent, would allow for increased use without higher power demands. Global average temperatures are set to rise by 2.7F by the 2030s, based on the latest climate change models - caused by emissions from human activities. These temperature increases are a global average and seem to match the target set by the UN as part of the Paris Climate agreement, but could go higher. Experts predict that without significant mitigation, with major reductions in greenhouse gas emissions, global temperatures will likely exceed the 3.6F threshold by the end of the century, resulting in dramatic changes to the global climate. Previous research has examined the impacts of higher future temperatures on annual electricity consumption, or daily peak load for specific cities or states. However, this new study is the first to project residential air conditioning demand for the entire United States. They have incorporated observed and predicted air temperature, heat and humidity changes, as well as discomfort indicators based on current feedback from people. They looked at air conditioning use by households across the contiguous US, in data collected by the US Energy Information Administration between 2005 and 2019. They didn't look at the impact of any population increases, keeping estimates to current population levels, or other factors driving air conditioning demmand, such as affluence, and instead focused purely on the influence of climate change. 'We tried to isolate just the impact of climate change,' said Renee Obringer, an environmental engineer at Penn State University and lead author of the new study. 'If nothing changes, if we, as a society, refuse to adapt, if we don't match the efficiency demands, what would that mean?' In order to keep using air conditioners, without causing rolling blackouts, the team say significant efficiency improvements are needed to the technology. These improvements could supply the additional cooling needed to achieve current comfort levels after 3.6F global temperature rise without increased demand for electricity, the new study found. Increased efficiency of 1 per cent to 8 per cent would be required, depending on existing state standards and the expected demand increase, with Arkansas, Louisiana and Oklahoma on the high end of efficiency improvement demand. The biggest risk to the grid will come during heat waves, which are predicted to happen more often as the climate changes in the coming decades. These heatwaves are expected to be more extreme and pose increased risk to humans, leading to much greater use of air conditioning units. 'Electricity generation tends to be below peak during heat waves as well, further reducing capacity,' Obringer explained. If demand exceeds capacity, then the energy firms would have to stage rolling blackouts during a heat wave to avoid grid failure, the team predict. This is similar to what happened in California in August 2020, during an extended period where record heat sometimes topped 117F. "We've seen this in California alreadystate power suppliers had to institute blackouts because they couldn't provide the needed electricity," Obringer said. There were an estimated 600 deaths linked to the extreme heat during that period, but the true toll may have been in the thousands. The consequences of the grid failing on a regular basis would hit those in low income, non-white and older areas the hardest, said Orbinger. The largest increase in demand for electricity will come from the hot south and southwest, according to the report. It gives an example of Arizona, finding that if households in the state increase air conditioning use by 6 per cent, the amount estimated to be needed to meet 2.7F warming, it would increase demand by 30 kilowatt hours per month. This would place an additional 54.5 gigawatt hours of demand on the power grid every month. Over a year Arizona uses 75.1 terawatt hours - or 75,100 gigawatts. The midwestern states are also predicted to see some of the highest increases in electricity demand from air conditioning over the next decade, they found. The added demand of global temperature rise from 2.7F to 3.6F, as currently predicted, could triple demand in Indiana and Ohio, underlining the importance of mitigation to limit temperature increases, Obringer said. "It's a pretty clear warning to all of us that we can't keep doing what we are doing or our energy system will break down in the next few decades, simply because of the summertime air conditioning," said Susanne Benz, a geographer and climate scientist at Dalhousie University in Halifax, Nova Scotia, not involved in the study. "When they say there's going to be two weeks where you don't have cooling on averagein reality, some people will have cooling. Disadvantaged people will have less cooling.' The findings have been published in the journal .