The big stories from the last year in electricity

The think tank Ember just released its yearly Global Electricity Review. In this episode, I chat with co-authors Nicolas Fulghum & Kostantsa Rangelova about the biggest stories in the global power sector in 2025. We geek out over the record-breaking scale of solar deployment, the game-changing role of batteries in shifting midday power to the evening, and the tantalizing possibility that India will not follow China’s coal-heavy development path and that global fossil fuel generation has finally plateaued. 📌 Instructions to add paid episodes to your preferred podcast app via mobile / desktop (PDF transcript) (Active transcript) David Roberts Hello. Hi. Greetings, everyone. This is Volts for April 22, 2026: “The big stories from the last year in electricity.” I’m your host, David Roberts. Every year, the think tank Ember puts out its Global Electricity Review — a comprehensive look at electricity generation around the world, delving into which countries are getting power from which sources, and how those numbers are shifting over time. Last year I talked with them about the 2025 edition, which was fun and enlightening, so when the 2026 review landed, I thought I’d come back for an update. This year’s report has some striking findings. Notably, global fossil generation fell in 2025 — a rare event, and the first time it’s happened outside of a recession or an unusually mild weather year. Solar and batteries just keep on booming. Countries like Australia and Chile are showing what truly green grids can look like, in practice rather than theory. And there’s an interesting argument in the report about India — that it’s unlikely to repeat China’s coal-heavy development path, for structural reasons. To dig into all of this, I have two Ember veterans with me today — Nicolas Fulghum and Kostantsa Rangelova, both returning guests, though this is their first time appearing together. I can’t wait to geek out. With no further ado, Kostantsa Rangelova, Nicolas Fulghum, welcome to Volts. Thank you so much for coming. Kostantsa Rangelova Hello and thank you for having us. Nicolas Fulghum Thanks so much for having us. David Roberts I just want to jump in. Nick, I’ll start with you about some things that haven’t changed. You could just write this report every year and just say, “Hey, look, renewable energy is growing really fast again.” Let’s start, Nick, with that, which is I guess the same as last year. Technically, there are a couple of milestones this year. Wind and solar combined met 99% of demand growth around the world. I want to start with that first thing, because that’s crazy. People need to wrap their head around that. All demand growth is being met by renewables. Solar was 75% of that demand growth and overtook wind in total generation for the first time ever this year. The other notable thing is that solar, despite several boom years in a row, has hit the highest rate of growth in eight years, despite, of course, having a much larger base it’s working off of. Just tell us about renewables and the ongoing renewables story. Nicolas Fulghum As you say, some things never change. It’s difficult when you’re writing these reports to not end up with a headline that says “record solar growth.” Indeed, there is a section in the report that does have that name still. David Roberts It keeps breaking records. What can we do? Nicolas Fulghum It does keep breaking records. You can’t not say it if it happens. As you pointed out, we had this record-breaking solar growth in quite a few respects, both in terms of the absolute growth — 636 terawatt hours of solar generation was added in 2025. Just to put that into perspective, we’re talking about twice as much as the annual electricity demand in the UK. It’s a huge amount of generation that’s being added there. In relation to the demand growth, it’s 75% of the increase now. That’s way more than any other source grew. The second largest growth came from wind at 205 terawatt hours, about a third of the increase in solar. Then you go down to nuclear power and to gas, which grew about 36 terawatt hours. That’s then 18 to 20 times smaller than the increase in solar. David Roberts Which — I’m very curious — which nuclear and gas, who’s winning there? What are the relative levels there? Nicolas Fulghum It’s all within the margin of error. We have an increase in gas generation of 36 terawatt hours and a nuclear increase of 35 terawatt hours. David Roberts Oh, roughly the same. Nicolas Fulghum Roughly the same. David Roberts It’s hard not to say that over and over again because it really takes time, even if you hear that over and over again, to truly absorb the fact that renewables in terms of new power generation have won. They’ve won the game. That’s 99%. 99% is renewables and that is not because the entire world is gripped by concern for the children of Bangladesh. It’s incontestable now that this is the cheapest. Also should mention this, Nick, before we get off this topic — renewables overtook coal, which I was surprised by, because I thought coal had had a resurgence in 2025. Talk about that a little. Is it just — it did have a resurgence and solar’s was just bigger? Nicolas Fulghum No, we saw a small decline in coal generation in absolute generation for the first time in a while. A drop of 63 terawatt hours. If you combine that with the minor increase in gas and then another minor fall in other fossil generation, which is mostly oil, we end up with a small decline in fossil generation overall — a 0.2% drop. That’s the result of the trends that we’ve already mentioned of renewables and nuclear power together. Low-carbon sources are growing faster than electricity demand. David Roberts All the hype about coal, all the hype about how the war and everything is going to send people running back to coal — all that did not show up in the numbers then. Nicolas Fulghum Not yet in 2025. We expect that even if there might be a short-term switching of fuel sources, it wouldn’t be an increase in fossil generation overall. If there is a reaction to the recent conflict in the Middle East, it would be largely a switching from one fuel source — from gas, for example, if it’s too expensive, to coal. But make no mistake there as well, that would be short-lived. Coal prices have also risen. Countries that are importing coal don’t have an amazing option in coal just on the side. It is very much you’re choosing between two poor options. I think it’s best summarized in the words that Xi Jinping uttered the other day where China was congratulating itself on having taken a renewables-heavy development path in recent years and the benefits of energy security that has brought. To hear that explicitly said from China, I think says everything about whether the future for energy security sits in renewables or it sits in coal. David Roberts It was a good idea for all the reasons he says in the first place. Then we go and reinforce what a good idea — just so there’s no remaining doubt. Let’s clear it up that that was the smart thing to do. The last question about renewables is how long could this go on? Where are we on the S curve? Do you think we’re still just heading up on the S curve? Are we close to maturity? Should we expect again in 2026, 27? How long can this surreal boom in renewables go on? Nicolas Fulghum As you noted, there is always the expectation that once the technology matures, at least you might stay with high absolute growth numbers. But usually your growth rates come down. With solar, what we’ve seen is that 2025 had the highest percentage rate — 30%, the highest rate in eight years — which isn’t a common feature among technologies that reach maturity. Even though solar is very much a mature technology in the market, obviously now. David Roberts It’s wild. I want more explanations. It seems there’s an element of magic involved. It is a mature technology. It is getting better, but not at the rate it was. It just seems more than the sum of i…