A Super El Niño Tests the Transition. It Does Not Accelerate It.
The forecasts are now firm enough to plan around. The World Meteorological Organization now puts the chance of El Niño developing this summer at 80 percent, holding at or above 90 percent through November, and likely at least moderate in strength. NOAA's June forecast goes further, placing the odds of a very strong, or "super," event by the turn of the year at better than three in five. El Niño is the warm phase of the El Niño-Southern Oscillation, the Pacific Ocean temperature cycle that reorganizes weather across much of the planet. A strong one usually delivers the hottest year on the record books.
The reflexive conclusion is that a record-hot year strengthens the climate case and pushes low-carbon technology up the priority list. I understand why people reach for it. For the system I work in, it is the wrong call in the near term.
Start with what a strong El Niño does to a grid. It suppresses rainfall across large hydropower regions and drives heat that lifts electricity demand for cooling. The two effects arrive together. During the 2015-2016 event, Colombia, which draws roughly three-quarters of its electricity from hydropower, saw rainfall fall about 40 percent and reservoir levels drop by 60 to 70 percent. The lights stayed on because the thermal fleet, the gas and coal plants, carried the load the dams could not. Hydropower is the conversion of falling water into electricity, and when the water stops falling, that capacity is simply gone. India's operators are planning the same way into this event, modeling higher coal generation to cover the gap.
So the first-order effect of a super El Niño is not more clean power. It is more reliance on whatever is firm and dispatchable, which today still means a great deal of gas and, in many systems, coal. Dispatchable means power you can call on at will, independent of weather. That is the property a heat-stressed grid values most, and it is exactly the property that variable renewables, without storage or firm backup, do not provide.
The strongest objection runs the other way. A visible climate year raises political and corporate attention, and attention moves policy. The last super El Niño coincided with the Paris Agreement. There is something to this. Salience does rise. But salience is thin and it fades, and it competes against a harder signal: the price and reliability of power during the event itself. When a grid is rationing, or a region is paying spot prices through the roof, the lesson decision-makers take away is rarely "build more of what just failed us." It is "secure firmness." A hot year can lift the rhetoric of decarbonization while pushing the economics toward the assets decarbonization is meant to retire. Both can be true at once, and the second one writes the checks.
The more useful question is not whether a hot year helps or hurts the transition. It is what a fast climate shock does to infrastructure that plans on a slow cadence. A grid is built over decades. An El Niño arrives in a single season. That mismatch, the rate of change outrunning the rate at which we can build and adapt, is what I have called the Temporal Trilemma. A super El Niño is the clearest illustration of it I can point to. The problem is not that we lack the right destination. It is that the environment is moving faster than the plan.
This is where it lands on the part of the build-out that matters most right now. Data centers are the fastest-growing source of new electricity demand, and the artificial intelligence facilities driving that growth are unusually exposed to the conditions a super El Niño produces. They concentrate heat, which they reject largely through evaporative cooling, a process that consumes water by turning it to vapor. Data centers in Texas were on track to use around 49 billion gallons of water in 2025, a figure projected to grow several times over by 2030. Across the United States, data centers consumed an estimated 17.4 billion gallons directly in 2023, with projections running far higher by the end of the decade.
Now run a super El Niño through that. The same heat that spikes a region's electricity peak also raises the cooling load inside the facility, at the moment local water is most stressed by drought. The grid connection the facility relies on is strained by the same heat event. Three constraints that are usually discussed separately, power, water, and heat, converge on the same site in the same season. The effect on expansion is not that developers suddenly prioritize sustainability. It is that they cannot site and power at the speed they had planned. The constraint is physical, not reputational.
I argued in 2016 that power, not compute, would ultimately be the binding constraint on this industry. A super El Niño does not change that thesis. It stress-tests it, and in public. The facilities that struggle in 2026 and 2027 will not struggle for want of chips. They will struggle for firm power and available water in places where both are suddenly short.
None of this is an argument against decarbonization. It is an argument about sequence. You do not reach a low-carbon, resilient system by treating a climate shock as a marketing tailwind. You reach it by sequencing the build so that firmness, water, and speed-to-power are solved in the right order, ahead of the demand rather than behind it. That sequencing is what the Structured Transition Model is for. It treats resilience and decarbonization as a single ordered problem rather than competing goals, which is the only framing that survives a year like the one ahead.
The decision facing data center developers and the utilities that serve them is not whether to go green. It is whether their plan can absorb a shock that arrives faster than the infrastructure can be built. A super El Niño is going to ask that question for them. The ones who have sequenced their power strategy will answer it well. The ones who treated power as an afterthought to compute will not.
I wrote Five Nines and Fast Power about this gap between how fast we want to build and how fast power can actually be delivered. The coming year is going to make the argument better than I can.
Questions and Answers
Is a super El Niño good for the energy transition? In the near term, no. A strong El Niño suppresses hydropower and raises cooling-driven electricity demand at the same time, which pushes grids to lean harder on firm, dispatchable generation that today is mostly gas and coal. The lasting effect is a repricing of resilience and firm power, not faster adoption of low-carbon technology.
How does El Niño affect hydropower and electricity supply? El Niño reduces rainfall across many hydropower regions, lowering reservoir levels and cutting generation. During the 2015-2016 event, Colombia, which relies on hydropower for about three-quarters of its electricity, saw rainfall drop roughly 40 percent and reservoirs fall 60 to 70 percent, forcing the grid onto thermal backup to avoid shortages.
Why would a record-hot year increase fossil fuel use? Heat raises electricity demand for cooling while drought cuts hydropower output. To keep the grid reliable, operators dispatch firm capacity, which in most systems still means gas and coal. India's grid operators, for example, are planning higher coal generation to cover the gap during the current event.
How does a super El Niño affect AI data centers? AI data centers reject heat largely through evaporative cooling, which consumes water. A super El Niño raises their cooling load and local electricity peak at the same time drought stresses water supplies, and strains the grid connection they depend on. Power, water, and heat converge on the same site in the same season, which slows expansion.
What is the Temporal Trilemma? The Temporal Trilemma is the problem of a fast-changing energy and climate environment outrunning the slow cadence at which infrastructure can be planned and built. A grid is built over decades; an El Niño arrives in a single season. The binding constraint becomes the rate of change, not the choice of technology.
How should data center developers respond? By sequencing the build so that firm power, water, and speed-to-power are resolved ahead of demand rather than after it, treating resilience and decarbonization as one ordered problem. The Structured Transition Model sets out that sequence.