I had a lovely time in Columbus, Ohio yesterday (August 27, 2026), doing a keynote for the Ohio Manufacturers' Association annual energy conference. The talk was titled "Electricity Demand Growth and Data Centers: A Guide for the Perplexed", and it drew on my work in the past
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By Jonathan Koomey, Zachary Schmidt, Karl Hausker, Holmes Hummel, and John Weyant Researchers and practitioners participating in the seventh assessment cycle of the Intergovernmental Panel on Climate Change (IPCC) can now rely on updated scenario decomposition tools to accelerate scenario troubleshooting and analysis. These tools, released today by the World
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The continued expansion of the global data center industry has drawn increasing attention to onsite water use and the energy efficiency of infrastructure (which is linked to water used in cooling) [1]. Some data centers rely on water primarily for cooling, and as the sector grows, so does interest in
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For more than a decade, since my old friend Richard Hirsh and I wrote this article for the Electricity Journal (Hirsh and Koomey 2015), we've compiled Energy Information Administration data every year to track recent developments for the US. This compilation can be tricky because of quirks in
Read moreMy talk, titled "A rapid tour of recent developments in solar, wind, batteries and enhanced geothermal power generation" summarizes recent progress with renewables. The key slide is this one, from EMBER: What many fail to understand is just how powerful manufacturing scale economies, network externalities, learning by doing,
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I’m proud to share a report we created in collaboration with Gridlab, released today, Monday March 23, 2026, 9am PT. Below is a link to the final report. Koomey, Jonathan, Zachary Schmidt, Priya Sreedharan, Nikhil Kumar, and Taylor McNair. 2026. Separating fact from fiction in data center electricity forecasts:
Read moreOn February 10th, Veolia and Microsoft released a report on AI and energy, water, and waste management. One of the short chapters in that report is a framing article about AI and energy use by me and Eric Masanet at UC Santa Barbara. The article distinguishes three ways AI might
Read moreIn the previous post, we announced our new Python package that helps modelers explore the key greenhouse gas emissions drivers in their scenarios. This post shows examples of visual dashboards that these tools allow you to create. There are three main dashboards, as documented in Koomey et al. 2019 and
Read moreTLDR: Below you can download a new open-source python package for calculating and comparing key drivers of emissions using outputs from Integrated Assessment Models. In 2004-2006 I served on the dissertation committee of Holmes Hummel at Stanford University. Holmes's thesis showed how a commonly used identity
Read moreWith recent growth in the data center industry has come increasing scrutiny about direct water use in these facilities [1]. Data center water use varies by facility type, location, and operational choices [2, 3]. These facilities use water because it’s usually more energy efficient to cool computing equipment using
Read moreThis report is the result of a collaboration between Koomey Analytics and the Bipartisan Policy Center in Washington, DC. Summary: Recent reports of unprecedented growth in electricity demand from data centers have appeared in many major news outlets. These headlines encapsulate two widely expressed concerns. First, that rising energy demand
Read moreWhen we first created the Koomey.com site circa 2010, we used Tumblr, which was a capable blogging site. We customized the site (with some difficulty) but it mostly performed well for a long time (almost 15 years). This past summer we started investigating other options, and soon settled on
Read moreThe modern data center lies at the heart of today’s digital global economy, performing computing tasks like e-commerce, communications, search, financial modeling, and artificial intelligence (AI). Data centers undergo constant change, both in the workloads they run 24x7 and the hardware that runs those applications. Lack of adequate
Read moreOur new article in Joule on data needs for understanding AI electricity use came out online today in Joule (link will be good until October 8, 2024). Here’s the summary section: As the famous quote from George Box goes, “All models are wrong, but some are useful.” Bottom-up
Read moreMy friend and colleague Danny Cullenward and I were on KQED Forum this morning, talking about the environmental impacts of our digital lives. Lesley McClurg was the host. You shouldn’t worry at all about your digital footprint, as we discussed in the show. It’s small and constantly improving,
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