The environmental benefits of renewable energy vary significantly from place to place, according to researchers at North Carolina State University. The gains associated with renewable energy depend on the types of conventional power generation that are being offset, and the benefits are not always confined to one particular region.
The experts hope their research will help to pinpoint the areas where investment in renewable energy will be the most beneficial.
“For years, researchers have taken different approaches to try to assess the environmental benefits of renewable energy,” said study co-author Professor Harrison Fell. “The Energy Information Administration started releasing detailed data on renewable power generation in 2018, and we realized that we finally had an opportunity to address this issue using real-world data.
“Our study is the first to quantify emissions reductions from solar and wind generation relying on renewable generation data across a broad array of regions, while also accounting for electricity trade between regions.”
For the investigation, the researchers analyzed data from regions across the contiguous 48 states that was collected between July 2018 and March 2020.
The most important finding is that the environmental value of renewable energy is significantly different across the country. More specifically, one megawatt hour (MWh) of renewable power varies depending on where that power was generated.
“For example, one MWh of solar power produced in Florida reduces carbon dioxide emissions by about twice as much as one MWh of solar power produced in California,” said study co-author Professor Jeremiah Johnson.
“That’s because California already has a cleaner grid when compared to other regions. So offsetting an hour of conventional power generation in California reduces CO2 emissions less than offsetting an hour of conventional power generation in Florida.”
Professor Johnson said that in the near term, the findings provide insight into where we should target investments in renewable power in order to maximize the environmental benefits.
The study also revealed that the environmental benefits of renewable energy often crossed regional lines. For example, renewable power generated in one state might be used to offset power generation in a neighboring state.
“Right now, renewable energy is largely driven by policies that vary from state to state,” said Professor Fell. “Our work here highlights one reason that this is not a very efficient approach to energy policy. A federal approach to renewable energy policy would be better able to account for the interstate nature of energy production, energy consumption and environmental benefits.”
“It will be interesting to see how the distribution of benefits changes as regions expand their sustainable energy infrastructure.”
The study is published in the journal Nature Sustainability.
By Chrissy Sexton, Earth.com Staff Writer