“The sustainability train has left the station.”

These are the words of the recently elected UN Secretary-General Antonio Guterres, who gave a blunt talk today on sustainable economies and climate change in New York City.

“Get on board or get left behind,” he continued. “Those who fail to bet on the green economy will be living in a grey future. Those who embrace green technologies will set the gold standard for economic leadership in the 21st century.”

For Guterres, who assumed his role last October, the logic is clear — renewable energy is the only way to ensure a robust economy in the future.

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“Thousands of private corporations, including major oil and gas companies, are taking their own action,”Guterres will say. “They know that green business is good business.  It is not just the right thing to do, it is the smart thing to do.”

Failing to invest in sustainability will almost certainly mean a country will be overwhelmed by the consequences of climate change, according to Guterres.

“The effects of climate change are dangerous and they are accelerating,” he said. “It is absolutely essential that the world implements the Paris agreement – and that we fulfil that duty with increased ambition.”

In many ways, the talk was an implicit criticism of US President Donald Trump who has threatened to withdraw from the Paris climate agreement, directed his administration to roll back climate regulations, and promised to invest in dirty energies like coal.

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But he didn’t spend his time rehashing all the hazards of fossil fuels. Instead, he dwelled on the promise of renewable energy, which has hit a tipping point in recent years.

Breakthroughs in technology and falling prices led to a 50% increase in solar power last year. More than half of new energy capacity in 2016 came from renewables, and in Europe that figure was higher than 90%.

In both US and China — the two biggest emitters — job growth in the renewable sectors surpassed growth in the oil and gas economies.

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India, the third largest emitter, plans to double its solar capacity this year, while Saudi Arabia, a bastion of oil, plans to bring 700 megawatts of solar and wind power online in the next few years.

Then there’s energy efficiency, a field that has the potential to generate $18 trillion in the years ahead, according to Guterres.

After detailing this momentum and potential, Guterres explained how the UN will help shepherd sustainability in the years ahead, with the ultimate goal of convening a climate summit in 2019.

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By then, he hopes, the world will be on the same page.

“Surely it is common sense to put our investments where they will generate the most savings, create the most jobs, deliver the biggest health dividends and have the most impact against global warming,” he said.