Ten years ago solar power barely existed as far as the world’s electricity ledgers were concerned — 1 percent of global supply, a rounding error in the age of coal and the atom. In 2026 it will almost certainly reach 10 percent and pass nuclear power, the mainstay of grids since the late 1970s, the BBC’s Jocelyn Timperley reports. No projection foresaw it. “[Solar] generating more electricity than all the world’s nuclear power plants is a pretty insane stat, for sure,” says Dave Jones, co-founder of the energy think tank Ember.

The engine, and the price

“Solar is now the engine of the power transition,” says Jan Rosenow, a professor of energy and climate policy at the University of Oxford. It is the fastest-growing source of new electricity in history, and in 2025 it met three-quarters of the world’s growth in electricity demand, outstripping wind. The trigger, Jones argues, was a collapse in panel prices in 2023–24 that pushed the world into an era of what he calls “offensively cheap” solar. “A panel in itself is just so unbelievably cheap,” he says. “It’s well under $100 (£75)… and that’s going to keep you generating electricity for 30, 40 years without any input at all.”

No permission required

China remains by far the biggest solar power, but it is not the whole story. In the United States, tariffs and federal policies that constrain renewables are expected to raise costs and slow expansion, says Alicia Zhao, an expert in US mitigation pathways at the University of Maryland — and yet, she adds, “solar is still one of the cheapest sources of new power in the US. And it is getting built regardless of political lines.” In Australia more than four million homes, well over a third of all households, now carry rooftop panels.

The most telling growth is happening where the state has failed the citizen. In Pakistan, Jones notes, “generally most of the solar boom has been out of people’s pockets… People can afford it, without needing to take out loans.” Lebanon, Nigeria and other sun-belt countries tell the same story, driven in part by unreliable grids and, recently, escalating oil prices. “In uncertain times, that speed and independence is extremely valuable,” says Rosenow. There is a familiar pattern here, worth naming as such: where administrations and utilities dawdle for a decade, ordinary people with a rooftop and a few hundred dollars simply secede from the queue.

What the sun cannot do alone

The sun, of course, keeps office hours. Turning daylight into power available at any hour requires batteries — and batteries have had their own cost revolution. “Solar plus storage is now routinely cheaper than new fossil plants in sunny regions,” says Rosenow. “Batteries have largely solved the daily problem of shifting midday sun into the evening.” Storage across seasons, cloudy spells and monsoons remains unsolved, he and Jones both caution, and integration into the wider electricity system still matters.

Caution also comes from Julia Souder, chief executive of the Long Duration Energy Storage Council, a global executive-led non-profit established at COP26. “There is an inherent danger in uncontrolled electrification, and adding massive new loads without built-in flexibility creates a fragile system,” she wrote recently. “Electrification is not automatically resilient.” Rosenow agrees that the limits on solar are now grids, storage and the pace of electrifying demand — not panels or cost. “The bigger question is no longer whether solar grows but whether our power systems and institutions can keep up.”

In the US, data centres and electrification have power demand growing for the first time in decades, Zhao says, with energy security a national priority. “Renewables already make up over 90% of new capacity in the US,” she says — a need that could create an opportunity for further renewable growth even without support from the current federal government. New ground is opening elsewhere too: solar on farmland — agrivoltaics, pairing panels with food production — is being touted as an answer to land-use objections.

The plateau that isn’t one

In 2026 the world’s solar capacity will keep rising, Jones says, but the rate of expansion may slow for the first time ever — because of China, which last summer changed its regime for managing and supporting new installations, prompting a burst of building in 2025 to beat the old price rules. Excluding China, more panels are being installed this year than last. “Wherever grid power is costly and unreliable, the economics keep pulling people towards solar,” says Rosenow, with one caveat: if Chinese panels become difficult to import, it will not happen at speed. “That’s where solar’s going, to not just be king of electricity, but king of energy,” says Jones. A decade ago, as he observes, no one was getting close to expecting where it has already arrived — and the growth in clean electricity has directly translated into fewer coal plants being built.