Global growth in solar "the largest ever observed for any source"
arstechnica.
A major report from the International Energy Agency for 2025 showed a key change. Solar power became the world's top source of new energy that year. The massive growth in solar was the biggest single-year jump ever seen for any energy source. This solar boom, plus a large increase in battery storage and mostly flat fossil fuel use, meant clean energy grew faster than rising demand. The IEA said this shows "the world has entered the Age of Electricity."
The IEA report studies all energy use. This includes power grids, cars, and home heating. It shows how energy use is changing. Electric vehicles are taking the place of gasoline cars. Heat pumps are replacing gas and oil heaters. The report found a clear pattern. Electricity demand grew twice as fast as overall energy demand. This is strong evidence that a new Age of Electricity is starting.
Data from 2025 shows electric vehicle sales jumped by almost 40 percent. Electric cars made up one out of every four new cars sold that year. While this increased electricity demand, the effect is still small. This change is likely why the rise in global oil use was so small—only 0.7 percent in 2025. That increase was less than half the average yearly rise over the previous ten years.
Heat pump sales did not grow much in 2025. However, in several countries, previous years' growth means heat pumps are now the main new heating system sold. Even so, cold weather in many places meant buildings were the main user of natural gas. Still, natural gas use grew by only 1 percent from 2024 to 2025.
These trends are expected to speed up in 2026. A conflict in the Middle East led to the closing of the Strait of Hormuz. This will severely disrupt global oil shipments. Several countries also depend on natural gas from Persian Gulf states. Even without other choices, use would drop because supply is lower and prices are higher. The world is now more likely to move away from fossil fuels faster. This shift will be driven by greater interest in electric options and government plans to prevent future fuel shortages.
To supply electricity for these new technologies, the main story is solar power. "The absolute increase of solar PV generation in 2025 is the largest ever observed for any source," the IEA stated. It made an exception for years marked by big rebounds from events like the COVID-19 pandemic. This means in a normal year, solar's growth in 2025 was record-breaking. By itself, solar's growth met one quarter of the rising demand for all energy types. For electricity alone, new solar power met over two-thirds of new demand.
Overall, solar generated over 2,700 terawatt-hours of electricity in 2025. This was more than double its output from just three years earlier. Solar now provides over 8 percent of the world's total electricity. Thirty different countries each installed at least one gigawatt of new solar power in 2025. Solar is now the largest power source by installed capacity, although other sources still make more electricity at the moment.
The solar boom is the main reason carbon-free energy grew faster than demand. These sources include hydropower, nuclear, solar, wind, and other renewables. As more things run on electricity, the world has reached a point where it can meet new demand without increasing carbon pollution. These clean sources met nearly 60 percent of the total growth in energy demand.
A key technology helping solar's growth is battery storage. Battery capacity was the fastest-growing power technology. New additions rose by 40 percent from 2024 to 2025. This reached 110 gigawatts of new capacity in 2025. This is apparently more than the highest one-year addition of natural gas capacity ever recorded. Total installed battery capacity is now over ten times what it was just five years ago. Batteries, when used with cheap solar power, can reduce the need for fossil fuel plants to provide backup power.
As noted, natural gas use increased by about 1 percent, mainly for heating. Coal use was mostly flat, rising by just 0.4 percent. While the United States used a little more coal, coal use in the European Union dropped below 10 percent of electricity production for the first time on record. Although China started many new coal plants in 2025, most were planned earlier during an energy crisis. China's coal use for electricity actually fell in 2025 because of its huge investment in renewables. China was responsible for 60 percent of the global growth in renewable energy in 2025.
Nuclear power remained stable in 2025. About 3 gigawatts of newly built plants balanced the retirement of 3 gigawatts elsewhere. China is also the major player in nuclear energy. It has enough plants being built that it will pass the United States in nuclear capacity if they are all finished. Construction began on 12 gigawatts of new nuclear plants in 2025. Nine of the ten total plants starting construction were in China.
Following these trends, carbon pollution from energy grew in 2025, but only by about 0.4 percent. While this set a new record high, the growth rate is much lower than in some past years. It also marks the third year in a row that the growth of emissions has slowed. One potentially critical detail is that China's emissions actually went down in 2025. The IEA says this was due to industrial changes and the fast growth of renewable energy.
The IEA also estimates that green technology installed since 2019 has had a big effect. This includes renewables, electric vehicles, heat pumps, and nuclear power. In 2025, these technologies displaced about 7 percent of total fossil fuel use. They also cut carbon emissions by 8 percent compared to a world without them. Just for coal, these systems displaced an amount equal to India's total coal use in 2025.
As mentioned earlier, it is hard to imagine that supply problems from the closing of the Strait of Hormuz will not affect global fossil fuel use in 2026. Past shocks have caused one-time drops in emissions. The key question now is whether this event will push many countries to move away from fossil fuels faster.