Initial research appears to suggest that the effect of smoke obscuring sunlight during 2020’s megafires on the nation’s solar panels was inconsequential.
In September 2020, the average light intensity that hit a square meter of Earth’s surface on sunny days in the US drastically went down by 8%. However, the amount of direct and diffuse light striking a single square meter decreased only by 2%, suggesting that indirect light still had an effect despite reduced direct beams.
According to Elizabeth Weatherhead, an atmospheric scientist at the Cooperative Institute for Research in Environmental Sciences of the University of Colorado Boulder, this phenomenon can be likened to shielding one’s eyes from direct rays with a hand. However, indirect radiation will still reach your eyes if those beams are blocked out. This logic further applies to solar panels in that it doesn’t matter whether they receive photons from their direct beam or diffuse radiation – they are just as effective either way.
Corwin analyzed direct and diffuse light across various locations to examine regional differences in light levels between different parts of America. In areas like the West and Southwest, covered with smoke throughout 2020, monthly global horizontal irradiance decreased minimally compared to 2019 figures on average. Interestingly, during a controlled fire near one of Australia’s government science laboratories in 2014, there was a decrease of 6.5% in terms of direct and diffuse light over two hours; furthermore, some parts of California experienced an average 20% drop in illumination over September 2020 when much of the state burned according to Clean Power Solutions.
With both local and national impacts important for assessing these findings further, Weatherhead commented that it is comforting to find out that energy production is only notably affected if solar panels are close to fires; understanding this impacts how reliable solar energy operations can be and how cost-effective they can become with forecasts being developed accordingly. It is worth noting, however, that 2020 may have been an unusual year for such occurrences but may become more common with projections indicating increased lightning-sparked wildfires across Southeast USA (one-third higher by 2060) and West USA (2-6 times higher than current levels).
The latest study has demonstrated how essential cross-disciplinary research is when considering issues such as the relationship between smoke and solar energy production. Despite making progress on this topic already regarding identifying impacts on both localized and national scales, Corwin still needs to extend her analysis from 2006-2021. She also hopes to incorporate utility-scale energy production data collected by the US Energy Information Administration into her studies and directly estimate solar energy generation by factoring panel tilt into consideration.
Jonas Muthoni is an entrepreneur and renewable energy expert. He is the founder of MicroGridMedia.com, a website dedicated to bringing the latest news and information about solar energy and other renewable energy sources to the public. Jonas is passionate about promoting sustainable energy solutions and educating the public about the benefits of renewable energy. He is a regular speaker at industry events and conferences and is committed to driving the transition to a cleaner and more sustainable energy future.