The findings of the study, released late on Wednesday, drew praise from the coal and nuclear industries and a mixed reaction from renewable energy groups - some of which said the report's recommendations could help them too. President Donald Trump campaigned on a promise to revive the coal industry, and has repeatedly expressed doubts about climate change.
Obama introduced regulations meant to slash emissions of carbon dioxide, which are blamed for climate change. Similarly, recommendations were added that coal and nuclear plants be shored up in order to save power grid reliability, while the report's actual data showed no reliability problem in need of solving.
The study concluded the already widely-held view that cheap natural gas and low demand drive the decline in coal and nuclear power. It is important for policy makers to consider their intended and unintended effects..
Critics of the report say it greatly underestimates the viability of renewable energy and fails to focus in on the robust amount of renewable resources available to operators after grid stabilization, like new battery storage technology and innovative solar power distribution tools.
But that draft had not yet been reviewed by the administration, the last step before publication. It also calls for changes to how wholesale electricity is traded and easier permitting for resources such as coal, nuclear and hydropower.
This is a much-needed, pragmatic look at US electricity reliability and resilience, including the priority of maintaining critical clean baseload power as electricity markets change, said Rich Powell, director of ClearPath, which advocates for nuclear and hydropower.
Environmentalists objected to the study, questioning results that stated renewables - particularly wind and solar - hindered the stability of the grid.
Dr. Karen Wayland, executive director of Nevada's Clean Energy Project and a former Department of Energy analyst, said today's clean-energy sources provide flexibility without threatening grid reliability.