To limit climate change, by 2030 the world must install the equivalent of the current largest solar park — every day. The rate of energy efficiency improvements will have to triple the rate of the past two decades. And by 2035, the sale of the internal combustion engine needs to be a thing of the past.

Those are some of the items in a new International Energy Agency report titled “Net Zero by 2050: A Roadmap for the Global Energy Sector,” which warns that the pathway to net zero is “achievable” but “narrow.”

The report hails the rapid growth in the number of countries that have pledged to achieve net zero emissions; those pledges now cover about 70 percent of global emissions of carbon dioxide. China has pledged to reach net zero emissions by 2060.

But the report warns that in many cases there is nothing backing up the pledges. Most of them “are not yet underpinned by near-term policies and measures,” the report said. Even if successfully fulfilled, the pledges to date would still fail to cover 22 billion tons of carbon dioxide emissions worldwide in 2050.

“We see a growing gap between the rhetoric and what is happing in the energy markets,” Fatih Birol, executive director of the IEA, said.

With international leaders set to convene in Glasgow in six months to outline climate measures, the “commitments made to date fall far short of what is required by that pathway,” the IEA report said.

But the IEA notes that overhauling the planet’s climate is a tremendous economic opportunity. According to the agency, energy investment would surge to $5 trillion by 2030, adding 0.4 percentage points to annual global growth. Thirty million jobs would be created, though 5 million would be lost. And by 2030, global GDP could be 4 percent higher than it would be if the world economy continued on its current path.

In the report, the IEA has tried to spell out the measures needed to reach net zero by 2050 and to provide a “road map” that would outline interim steps along the way. The IEA road map is aimed at keeping climate change to 1.5 degrees Celsius or 2.7 degrees Fahrenheit — slightly more ambitious than the 2 degree Celsius target set in the Paris climate accord in December 2015.

“It’s a really important milestone having the IEA on record,” said James Newcomb, managing director of RMI, a Colorado-based consulting firm. “We’re on steep and ongoing technological learning curves for the most important transitions.”

The road map, however, is a difficult one. It says that the sale of electric vehicles must go from around 5 percent of global car sales today to more than 60 percent by 2030. The amount of solar and wind power added every year would have to quadruple.

Psychological research shows that climate change can alter an individual’s mental health both directly and indirectly, impacting how we respond to this crisis. (John Farrell/The Washington Post)

The agency also says that most of the global reductions in greenhouse gases through 2030 will be based on readily available technologies. However, the study notes, “in 2050, almost half the reductions come from technologies that are currently at the demonstration or prototype phase.”

Birol said that “in the next 10 years, we must make the most out of clean energy options such as solar, such as wind, such as [electric vehicles]. Then we have to push innovation very strongly in order to make sure that the technologies under development today” are adopted.

If the international community could stick to the IEA road map, there would be no need to invest in new fossil fuel supplies, the report says. Coal demand would plunge from 90 percent to just 1 percent of total energy use in 2050. The demand for natural gas would drop by 55 percent, and oil would tumble 75 percent to 24 million barrels per day, down from around 90 million barrels in 2020.

“It is incredibly significant that the IEA is saying there is no need for investment in new supply,” Newcomb said. “This is a message certainly working its way through the financial community.”

Instead, investment would focus on electricity transmission and distribution grids, more than tripling from now through 2030. The number of public charging points for electric vehicles would soar from around 1 million today to 40 million in 2030, requiring investments of almost $90 billion in 2030.

President Biden has also set high climate ambitions, vowing to cut greenhouse gas emissions by 50 to 52 percent, compared with 2005 levels, by 2030.

Birol said new technologies could lead to new competition for critical materials such as copper, cobalt, manganese and rare earth metals, use of which would grow almost sevenfold between 2020 and 2030 on the net zero pathway. The materials are used for climate-friendly energy devices such as batteries.

The outcomes could be perilous. “This creates substantial new opportunities for mining companies,” the report says. “It also creates new energy security concerns, including price volatility and additional costs for transitions, if supply cannot keep up with burgeoning demand.”

But the IEA head also flagged possible weaknesses in emerging markets where many governments lack the funds to make the large investments needed. He said that if industrialized nations fail to subsidize poorer nations, 90 percent of new emissions would come from less-developed nations. Due to decreases in oil demand, many oil-rich countries could face a drop in government revenues.

The report predicts that by 2050, due to energy efficiency, global energy demand will be around 8 percent lower than today. But it will be serving an economy more than twice as big and a population with an additional 2 billion people. That remaining energy demand largely will be met with renewable resources.