Gov. Andrew Cuomo doubled down last week on his blame-the-messenger approach to New York’s growing shortage of natural-gas supplies by ordering the Department of Public Service to “broaden its investigation” of National Grid and threatening to “find another franchisee.”

Anything, rather than admit that his own policies are at fault.

The utility has stopped taking new gas customers in parts of Long Island, Brooklyn and Queens where it can’t handle the new demand — because Team Cuomo vetoed the proposed Williams pipeline to bring in supplies from New Jersey. (Jersey is also blocking the pipeline, since Gov. Phil Murphy is appeasing the same green extremists.)

National Grid gave months of warning that it would need to impose the moratorium if fresh supplies weren’t ensured.

Con Ed did the same in advance of its recent new-biz moratorium in most of Westchester, which was also prompted in good part by the nixing of new pipelines.

This is the point of the yearslong green war on pipelines: You can’t burn gas or oil you can’t get.

But would-be consumers are, of course, furious. Which leaves Cuomo and like-minded pols blaming the utilities. Hence the gov’s “broadened investigation” — which is supposed to find, what? That National Grid doesn’t want more customers?

Much of the public eats it up when pols bash utilities. But it won’t change the facts. Give the franchise to another company, and it still won’t be able to conjure fuel out of the air.

Of course, it’s been years since reality mattered when it came to Cuomo’s energy policies.

He ignored both science and upstate’s economic straits when he made the fracking ban permanent in 2014. (Meanwhile, Pennsylvanians prosper by fracking their share of the Marcellus Shale.)

Then there’s his renewable-energy goals. In 2015 he pledged to run the state on 50 percent renewable energy by 2030. New York actually lost ground on that front last year, but he just upped it to 70 percent — and 100 percent by 2040.

Never mind that this requires vast solar and wind farms that many communities refuse to tolerate plus major new power-transmission lines and new battery technology that may not exist for decades.

Nor that the carbon-free goals will turn even harder to reach when the Cuomo-engineered shutdown of the Indian Point nuclear-power plant begins next year: It supplies a quarter of New York City’s electricity, and there’s no way to get enough “green” replacement power in time.

The United States is now the world’s top energy producer. There’s no reason for any kind of power or fuel shortage in New York, but the Con Ed and National Grid moratoriums are merely a taste of what’s coming.

Be sure to thank Cuomo when the lights go out.