PRINCETON, N.J. — When it comes to renewable energy, solar power is probably the most well known source around. As countries and power companies worldwide look at battling climate change, a new study finds climate change may already be affecting the future of solar energy. Researchers say global warming will likely bring more cloudy days to some areas, including regions counting on the sun’s power.
The Princeton University-based study is the first to look at how reliable solar energy will be on a day-to-day basis in a future impacted by climate change. Using satellite data and models on the climate emergency, researchers were able to project how much sunlight will reach the ground as the Earth’s atmosphere changes.
Climate change blocking out the sun
The findings reveal higher surface temperatures will likely result in more moisture, aerosols, and particles in the atmosphere. These changes may cause an overall decrease in solar radiation breaking through and a higher number of cloudy days. This potential climate shift brings incredible uncertainty to areas considered key to the future of solar energy production. Two important locations which could be impacted are the American Southwest and Middle East.
“Our results could help in designing better solar power plants and optimizing storage while also avoiding the expansion of solar power capacity in areas where sunlight intermittency under future climate conditions may be too high to make solar reliable,” corresponding author Amilcare Porporato says in a university release.
“To use an academic metaphor, in terms of solar power, semiarid places are now like students who get an A nearly every day,” Porporato adds. “Now, climate change is disturbing the usual dynamics of the atmosphere and the regularity of the solar radiation reaching the planet’s surface. We tried to quantify how much more often those A’s could become B’s, or even C’s, as a result.”
First author Jun Yin adds most studies on solar energy focus on the average levels of sunlight our planet receives. Their new report however, looked at how consistent solar activity is likely to be as conditions worsen.
“The novelty of our approach was to point out that in some places there is going to be more uncertainty in day-to-day variability,” the researcher from Nanjing University of Information Science and Technology explains.
Future solar power hot spots affected
Along with co-author Annalisa Molini, researchers made their calculations using similar models scientists use to highlight flood and drought risks. Researchers say a lower reliability of sunny days also has a link to growing irregularities of moisture in the air. For arid regions like the Middle East, higher temperatures can also mean dryer soil. When this happens, Porporato says greater amounts of dust can get kicked up into the air, further diminishing solar radiation. The team adds these changes are already being seen by climate observation networks.
In the American Southwest, the future impact is much less certain. Yin reports that some models show more solar radiation reaching Earth, but others find this region will also suffer from an inconsistent supply of sunlight as well.
“We hope that policymakers and people in the energy industry can take advantage of this information to more efficiently design and manage photovoltaic facilities,” says Yin.
“Our paper helps identify efficient solutions for different locations where intermittency could occur, but at an acceptable level. A variety of technologies such as power storage, or power-operation policies such as smart curtailment, load shaping or geographical dispersion, are promising solutions.”
The team is now planning to examine climate persistency, the number of consecutive sunny or cloudy days regions will see. They add this is an important factor for solar power plants determining their output.
The study appears in the journal Nature Communications.