The United States could run its electric grid underground using air conditioners if climate change continues at its current rate – and there are no signs it will stop.
A study of household-level electricity demand from the American Geophysical Union warns that an increase in the use of air conditioners (AC) in the United States is likely to cause massive problems in the future. This increase in use will be driven by climate change. Higher peak temperatures in the summer and longer, more frequent heat waves will increase usage enough to overwhelm national power grids as they are now.
Unless networks are upgraded to become more efficient or receive increased capacity, the United States expects power outages.
“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 meet the demands of efficiency, what would that mean?
The researchers projected how summer energy use will change in the future, under two scenarios: these assume global temperatures rise by 1.5 degrees Celsius (2.7 degrees Fahrenheit) or 2.0 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels. Based on these temperatures, they estimate that electricity demand in the United States would increase overall by 8% and 13%, respectively.
Based on our current emissions, we are on track to exceed the 1.5°C warming scenario by the early 2030s, according to the Intergovernmental Panel on Climate Change (IPCC) report 2021. In fact, without significant effort, we will likely exceed the 2.0 degree Celsius threshold as well by the end of the century.
This study is the first to analyze the impact of higher temperatures on electricity demand and peak load for specific cities or states. It is also the first to project residential air conditioning demand on a large scale. Environmental data used in the projections included air temperature and heat, humidity and discomfort indices, as well as air conditioning usage figures, collected by the US Energy Information Administration (EIA) in 2005-2019 from statistically representative households across the contiguous United States.
That being said, the results aren’t perfect; the study only took into account the influence of climate on the use of air conditioning. Additional factors such as population increase, income changes, consumer behavior or other factors that may affect air conditioning demand have not been considered.
According to the team, it is possible that technological improvements (such as better insulation or better AC efficiency) will come along and allow the increased demand for AC to be covered without additional energy consumption. The team calculated that an efficiency increase of 1% and 8% would be needed for this. This figure varies depending on existing national standards and the expected increase in demand there; Arkansas, Louisiana and Oklahoma would need the most raises.
Heat waves will be a particularly difficult time for our networks and will also present the highest risk of death for the public. Worse still, energy production tends to drop below its peak during heat waves, further compounding the problem. In this scenario, it is very likely that energy utility companies will be forced to stage blackouts to avoid grid outages during heat waves.
The southern and southwestern regions of the country will experience the greatest increases in energy demand. For the state of Arizona, for example, if all households increase their AC power consumption by 6% – which the team says will be needed to compensate for 1.5 degrees of additional warming – the entire the state will see a monthly demand increase of 54.5 million kilowatt hours.
The new study predicted the largest kilowatt-hour increases in electricity demand in the already warm south and southwest. Under the 2.0 degree Celsius scenario, some cities in the region, such as Indiana and Ohio, could see their current energy demand triple over the summer months.
The article “Implications of the increase in the use of household air conditioning in the United States in a warming climate” was published in the magazine Earth’s future.