A recent study led by the TH Chan School of Public Health at Harvard University, and published in the journal Science Advances, revealed key data on the use of solar energy in the United States.
It confirmed that increasing solar generation by 15% in the northern country could lead to an annual reduction of 8.54 million metric tons of carbon dioxide (CO2).
More solar energy in the United States, less CO2 in the air
The research team demonstrated that the climate benefits of solar energy vary by region, clearly indicating where investments in clean energy generate greater environmental dividends.
“This study is exciting because it uses the power of data science to provide useful information to public policy makers and stakeholders on how to advance CO₂ reduction goals,” explained Francesca Dominici, director of the Harvard Data Science Initiative and lead author of the study.
The advantages of solar energy.
The study was based on the analysis of five years of hourly data (since July 2018) on electric generation, demand, and emissions, covering 13 energy regions in the country: California, Texas, Florida, Mid-Atlantic, Midwest, Carolinas, New York, New England, Southeast, Southwest, Tennessee, Central region, and the Northwest.
Through an advanced statistical model, it was possible to quantify for the first time the reduction in both immediate and deferred emissions resulting from the increase in solar generation:
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In California, a 15% increase in solar energy at noon resulted in a reduction of 147.18 metric tons of CO2 in the first hour; and 16.08 metric tons eight hours later.
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This type of impact also benefits neighboring regions. For example, the same capacity increase in California generated daily reductions of 913 tons in the Northwest and 1942 metric tons in the Southwest.
Solar energy is still a minority compared to fossil fuels
According to data from the U.S. Energy Information Administration, in 2023, 60% of the electricity generated in the country came from fossil fuels, while only 3.9% came from solar energy.
Solar energy is still a minority.
This reality positions the expansion of renewable sources as a key tool not only to reduce CO2 emissions but also to improve public health. It reduces exposure to atmospheric pollutants such as fine particles (PM2.5), associated with diseases, hospitalizations, and premature deaths.
Where solar energy performs best
The results indicate that areas like California, Florida, Texas, the Mid-Atlantic, the Southwest, and the Midwest would achieve significant climate benefits, even with modest increases in solar generation.
In contrast, in regions like New England, Tennessee, and the Central region, the impacts were minimal, even with significant increases.
