Is solar's growth finally slowing in the US?

Normally, we try to update you quarterly on what’s going on with the US electric grid since it provides a nice view of developing trends and smooths out some month-to-month randomness. Unfortunately, I was out of the office when last month’s data was released, so this will be a seven-month update on 2026 trends. The top line item is that energy use is continuing to rise, albeit not as quickly as headlines about data centers might lead people to believe. Beyond data centers, there’s a growing electrification—things like EVs and heat pumps—that is shifting energy demands onto the grid. Despite all of this, electricity use has risen by only 2 percent compared to the same period last year. At this time the previous year, demand had risen by 3 percent compared to the year prior. Some of this may be due to continued improvements in efficiency, which had largely kept electricity demand stable throughout the early 2000s. And some of it may be because more data centers are generating their own power so that demand doesn’t show up on the grid. So far, the growth in demand hasn’t reached apocalyptic levels. The other big story in recent years has been the explosive growth of solar power. The astonishing growth rates we’ve been seeing—over 30 percent year over year in many quarters—would inevitably come to an end as the ever-larger installed base would cause an identical increase to register as a smaller percentage change. But for the first seven months of 2026, there’s a smaller increase in generation. Through September 2026, solar generated 48 terawatt-hours more than it had the year before. For the same period in 2025, that number was 39 TWh. That’s still good for a growth rate of 22 percent, but it’s a considerable drop-off at a time when demand is growing, and solar is the cheapest way to meet it. Obviously, the federal government is currently hostile to renewables and has removed incentives for their use, which may be slowing down solar’s previously astonishing expansion.