The growth of renewable power, including wind and solar, has not harmed the reliability of the U.S. electricity grid, according to a draft U.S. Department of Energy study, echoing the findings of grid operators across the country.
The conclusion of the draft, dated July and viewed by Reuters, could ease fears in the renewable energy industry that the widely anticipated study would be used by President Donald Trump’s administration to form policies supporting coal plants at the expense of wind and solar.
“Numerous technical studies for most regions of the nation indicate that significantly higher levels of renewable energy can be integrated without any compromise of system reliability,” the draft says.
It added that growth of renewables could require the building of more transmission lines, advanced planning, and more flexibility to balance generation and meet demand. But it said that baseload power—coal and nuclear power—”is not as necessary as it used to be” given advances in grid technology.
Shaylyn Hynes, an Energy Department spokeswoman, said the draft was “outdated” and had not gone through “any adjudication” from career or political staff. The final report had been slated for release in early July, but now is not expected for at least a couple of weeks, she said.
The draft can be seen here. Bloomberg first reported on it on Friday.
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Energy Secretary Rick Perry had called in April for his department to examine whether regulations backing renewable energy use imposed by former president Barack Obama and other administrations “threaten to undercut the performance of the grid well into the future.”
Critics of wind and solar energy have argued that those technologies leave the U.S. power system vulnerable to shortages when the sun is blocked or the wind does not blow—meaning that coal, nuclear, and natural gas plants that do not depend on weather should remain the bulk producers.
Renewable energy is seen by many…