As solar energy use surges across the globe especially in developing regions aiming for carbon neutrality a new study warns of a growing threat to its reliability: solar power “droughts.”
Researchers from a recent study led by Lei et al. have identified periods of at least three consecutive days where solar power demand exceeds supply events they call solar power droughts. These shortages could leave millions without access to essential services like cooling or cooking, particularly in regions most vulnerable to climate extremes.
Analyzing solar energy patterns from 1984 to 2014, the study found that areas such as the western United States, eastern Brazil, Southeast Asia, and large parts of Africa experienced at least five solar power droughts annually. Over those 30 years, the frequency of these droughts increased by 0.76 events per decade. Climate change and rising energy demands were identified as key drivers behind this trend, responsible for nearly a third of these events.
The core issue researchers explain, is that the worst solar generation lags often occur during heatwaves precisely when electricity demand for cooling is highest. Inclement weather and air pollution can further reduce solar panel efficiency, making power shortages even more likely during critical periods.
Looking ahead, the researchers modeled the potential for future solar droughts under various climate scenarios. Under a medium-emissions pathway (Shared Socioeconomic Pathway 2-4.5), they found that by the 2090s, solar power droughts could become seven times more frequent and 1.3 times more intense than historical averages. However in low-emission scenarios, these events would peak by the 2060s and gradually decline.
The findings serve as a warning and a call to action: while solar energy is a cornerstone of sustainable development it must be supported with mitigation measures, diversified clean energy sources and resilient infrastructure. Without these the study suggests the transition to renewable energy may be undermined by the very climate shifts it seeks to address.
Ultimately, the researchers emphasize that reducing emissions today could pave the way for a “cooler and cleaner future,” where solar power remains a reliable solution in the fight against climate change.