A key Team de Blasio aide is fretting that the closure of the Indian Point nuclear-power plant will lead to more electricity coming from “dirty” fossil fuels. Yet the truth may be far worse.

If Indian Point closes as planned by 2021, “we will see localized impacts” before any clean-energy sources are up and running. That, The Post reported this week, is what top de Blasio energy aide Susanne Des-Roches told a forum earlier this year.

She feared the plant’s replacement power would be “heavy” on greenhouse gases. She also cited “cost impacts” from IP’s closure — i.e., higher electric bills. She’s right: Wind and solar “clean energy” is unlikely to be sufficient to replace IP’s 2,000 MW of juice — not by 2021, and quite possibly never.

Which leaves fossil fuels, particularly natural gas. So why does climate-change warrior Mayor de Blasio, DesRoches’ boss, support IP’s shutdown?

The plant is closing after spending years (and up to $200 million) fighting legal harassment by Gov. Cuomo, who (in a suck-up to anti-nuke radicals) claims IP puts the metro area at risk of nuclear contamination — which tons of evidence show is fear-mongering nonsense.

But fracking has made natural gas cheap and nuclear power less economical, so IP’s owners threw in the towel.

Thing is, high costs, unreliable juice and greenhouse-gas emissions are the least of New York’s post-Indian-Point concerns. The big question: Will there be enough power from any source, dirty or clean?

Cuomo has nixed pipelines for natural gas. Last month, he denied a key permit to a new Orange County natural-gas power plant. Con Ed is so worried about shortages, it’s spending $100 million a year on workarounds.

As we’ve warned before: Stock up on candles while you still can.