Environment Variables

For this 100th episode of Environment Variables, guest host Anne Currie is joined by Holly Cummins, senior principal engineer at Red Hat, to discuss the intersection of AI, efficiency, and sustainable software practices. They explore the concept of "Lightswitch Ops"—designing systems that can easily be turned off and on to reduce waste—and the importance of eliminating zombie servers. They cover AI’s growing energy demands, the role of optimization in software sustainability, and Microsoft's new shift in cloud investments. They also touch on AI regulation and the evolving strategies for balancing performance, cost, and environmental impact in tech. 

Learn more about our people:

• Chris Adams: LinkedIn | GitHub | Website
• Holly Cummins: LinkedIn | GitHub | Website

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

News:

• AI Action Summit: Two major AI initiatives launched | Computer Weekly [40:20]
• Microsoft reportedly cancels US data center leases amid oversupply concerns [44:31]

Events:

• Data-driven grid decarbonization - Webinar | March 19, 2025
• The First Eco-Label for Sustainable Software - Frankfurt am Main | March 27, 2025 

Resources:

• LightSwitchOps 
• Why Cloud Zombies Are Destroying the Planet and How You Can Stop Them | Holly Cummins
• Simon Willison’s Weblog [32:56]
• The Goal

If you enjoyed this episode then please either:

• Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:

Holly Cummins: Demand for AI is growing, demand for AI will grow indefinitely. But of course, that's not sustainable. Again, you know, it's not sustainable in terms of financially and so at some point there will be that correction. 

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams. 

Anne Currie: So hello and welcome to Environment Variables, where we bring you the latest news and updates from the world of sustainable software. Now, today you're not hearing the dulcet tones of your usual host, Chris Adams. I am a guest host on this, a common guest, a frequent guest host, Anne Currie. And my guest today is somebody I've known for quite a few years and I'm really looking forward to chatting to, Holly.

So do you want to introduce yourself, Holly?

Holly Cummins: So I'm Holly Cummins. I work for Red Hat. My day job is that, I'm a senior principal engineer and I'm helping to develop Quarkus, which is Java middleware. And I'm looking at the ecosystem of Quarkus, which sounds really sustainability oriented, but actually the day job aspect is I'm more looking at

the contributors and, you know, the extensions and that kind of thing. But one of the other things that I do end up looking a lot at is the ecosystem aspect of Quarkus in terms of sustainability. Because Quarkus is a extremely efficient Java runtime. And so when I joined the team, one of the things we asked well, one of the things I asked was, can we, know this is really efficient. Does that translate into an environmental, you know, benefit? Is it actually benefiting the ecosystem? You know, can we quantify it? And so we did that work and we were able to sort of validate our intuition that it did have a much lower carbon footprint, which was nice.

But some things of what we did actually surprised us as well, which was also good because it's always good to be challenged in your assumptions. And so now part of what I'm doing as well is sort of broadening that focus from, instead of measuring what we've done in the past, thinking about, well, what does a sustainable middleware architecture look like?

What kind of things do we need to be providing?

Anne Currie: Thank you very much indeed. That's a really good overview of what I really primarily want to be talking about today. We will be talking about a couple of articles as usual on AI, but really I want to be focused on what you're doing in your day job because I think it's really interesting and incredibly relevant.

So, as I said, my name is Anne Currie. I am the CEO of a learning and development company called Strategically Green. We do workshops and training around building green software and changing your systems to align with renewables. But I'm also one of the authors of O'Reilly's new book, Building Green Software, and Holly was probably the most, the biggest single reviewer/contributor to that book, and it was in her best interest to do so because, we make, I make tons and tons of reference to a concept that you came up with.

I'm very interested in the backstory to this concept, but perhaps you can tell me a little bit more about it because it is, this is something I've not said to you before, but it is, this comes up in review feedback, for me, for the book, more than any other concept in the book. Lightswitch Ops. People saying, "Oh, we've put in, we've started to do Lightswitch Ops."

If anybody says "I've started to do" anything, it's always Lightswitch Ops. So tell us, what is Lightswitch Ops?

Holly Cummins: So Lightswitch Ops, it's really, it's about architecting your systems so that they can tolerate being turned off and on, which sounds, you know, it sounds sort of obvious, ...

Host Chris Adams is joined by Charles Tripp and Dawn Nafus to explore the complexities of measuring AI's environmental impact from a novice’s starting point. They discuss their research paper, A Beginner's Guide to Power and Energy Measurement and Estimation for Computing and Machine Learning, breaking down key insights on how energy efficiency in AI systems is often misunderstood. They discuss practical strategies for optimizing energy use, the challenges of accurate measurement, and the broader implications of AI’s energy demands. They also highlight initiatives like Hugging Face’s Energy Score Alliance, discuss how transparency and better metrics can drive more sustainable AI development and how they both have a commonality with eagle(s)!

Learn more about our people:

• Chris Adams: LinkedIn | GitHub | Website
• Dawn Nafus: LinkedIn
• Charles Tripp: LinkedIn

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

News:

• The paper discussed: A Beginner's Guide to Power and Energy Measurement and Estimation for Computing and Machine Learning [01:21] 
• Measuring the Energy Consumption and Efficiency of Deep Neural Networks: An Empirical Analysis and Design Recommendations [13:26]
• From Efficiency Gains to Rebound Effects: The Problem of Jevons' Paradox in AI's Polarized Environmental Debate | Luccioni et al [45:46]
• Will new models like DeepSeek reduce the direct environmental footprint of AI? | Chris Adams [46:06]
• Frugal AI Challenge [49:02] 
• Within Bounds: Limiting AI's environmental impact [50:26]

Events:

• NREL Partner Forum Agenda | 12-13 May 2025

Resources:

• Report: Thinking about using AI? - Green Web Foundation | Green Web Foundation [04:06]
• Responsible AI | Intel [05:18] 
• AIEnergyScore (AI Energy Score) | Hugging Face [46:39]
• AI Energy Score [46:57]
• AI Energy Score - Submission Portal - a Hugging Face Space by AIEnergyScore [48:23]
• AI Energy Score - GitHub [48:43] 
• Digitalisation and the Rebound Effect - by Vlad Coroama (ICT4S School 2021) [51:11]
• The BUTTER Zone: An Empirical Study of Training Dynamics in Fully Connected Neural Networks
• BUTTER-E - Energy Consumption Data for the BUTTER Empirical Deep Learning Dataset [51:44]
• OEDI: BUTTER - Empirical Deep Learning Dataset [51:49]
• GitHub - NREL/BUTTER-Better-Understanding-of-Training-Topologies-through-Empirical-Results
• Bayesian State-Space Modeling Framework for Understanding and Predicting Golden Eagle Movements Using Telemetry Data (Conference) | OSTI.GOV [52:26]
• Stochastic agent-based model for predicting turbine-scale raptor movements during updraft-subsidized directional flights - ScienceDirect [52:46]
• Stochastic Soaring Raptor Simulator [53:58]
• NREL HPC Eagle Jobs Data [55:02]
• Hype, Sustainability, and the Price of the Bigger-is-Better Paradigm in AI 
• AIAAIC | The independent, open, public interest resource detailing incidents and controversies driven by and relating to AI, algorithms and automation

If you enjoyed this episode then please either:

• Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:

Charles Tripp: But now it's starting to be like, well, we can't build that data center because we can't get the energy to it that we need to do the things we want to do with it. we haven't taken that incremental cost into account over time, we just kind of ignored it. And now we hit like the barrier, right? 

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams. 

Welcome to Environment Variables, where we bring you the latest news and updates from the world of sustainable software development. I'm your host Chris Adams. If you follow a strict media diet, you switch off the Wi-Fi on your house and you throw your phone into the ocean, you might be able to avoid the constant stream of stories about AI in the tech industry. For the rest of us, though, it's basically unavoidable. So having an understanding of the environmental impact of AI is increasingly important if you want to be a responsible practitioner navigating the world of AI, generative AI, machine learning models, DeepSeek, and the rest. Earlier this year, I had a paper shared with me with the intriguing title A Beginner's Guide to Power and Energy Measurement, an Estimation for Computing and Machine Learning. And it turned out to be one of the most useful resources I've since come across for making sense of the environmental footprint of AI. ...

For this episode of TWiGS, Chris and Asim discuss the latest developments in emissions reporting, AI energy efficiency, and green software initiatives. They explore the AI Energy Score project by Hugging Face, which aims to provide an efficiency benchmark for AI models, and compare it with other emissions measurement approaches, including the Software Carbon Intensity (SCI) for AI. The conversation also touches on key policy shifts, such as the U.S. executive order on AI data center energy sourcing, and the growing debate on regulating the data center industry. Plus, they dive into the Beginner's Guide to Power and Energy Measurement for Computing and Machine Learning, a must-read for anyone looking to understand energy efficiency in AI. 

Learn more about our people:

• Chris Adams: LinkedIn | GitHub | Website
• Asim Hussain: LinkedIn | Website

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

News:

• AI Energy Score | Hugging Face [04:04]
• A Beginner's Guide to Power and Energy Measurement and Estimation for Computing and Machine Learning [20:00]
• Executive Order on Advancing United States Leadership in Artificial Intelligence Infrastructure [32:10]
• AI datacenters putting zero emissions promises out of reach • The Register [45:30] 
• xAI's "Colossus" supercomputer raises health questions in Memphis | TechCrunch [38:22]

Events:

• Practical Advice for Responsible AI (February 27 at 6:00 pm GMT · London) [50:30]
• GSF Oslo - February Meetup (February 27 at 5:00 pm CET · Oslo) [50:52]  

Resources:

• CodeCarbon [06:00]
• Optimum Benchmark | Hugging Face [06:12]
• SCI for AI | GSF [06:40]
• ITU [07:07] 
• Responsible AI Institute [10:24]
• EcoLogits [15:07]
• NREL Data Catalog [25:50]
• Kepler | CNCF [30:14]
• Environment Variables Ep97: How to Tell When Energy is Green with Killian Daly [33:52]
• The Problem of Jevons' Paradox in AI's Polarized Environmental Debate | Sasha Luccioni [49:32]  

If you enjoyed this episode then please either:

• Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!
• Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:

Asim Hussain: There's this assumption out there that we're trying to hunt for the right, true essentialist value of measurement, and it really isn't like that 

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams. 

Hello, and welcome to another edition of This Week in Green Software. I'm your host, Chris Adams. Today, we're tackling an ongoing conversation in software today, predicting, measuring, and accurately reporting emissions data, particularly in AI. And as AI adoption skyrockets, so does its energy footprint.

Putting pressure on data infrastructure and sustainability goals. So today we'll be looking at a few new reports, what's going on, and generally doing a kind of roundup of the news and recent events along this. Because it's not all doom and gloom, although there is some. I'm also joined today by my friend and frequent collaborator, Asim Hussain.

Asim, can I give you some space to introduce yourself before we do our weekly, well, semi weekly, news roundup?

Asim Hussain: Not so weakly, anymore. Yeah. Hi. I'm Asim Hussain. I'm the Executive Director of the Green Software Foundation. So we are a standards organization and our mission is a future where software has zero harmful environmental impacts. And you might not be surprised to hear that we believe one of the best paths forwards is developing standards through consensus of multiple organizations.

Because through setting those standards, you can direct billions of dollars into the right places. And if you do it wrong, you can direct billions of dollars into the wrong places. So let's do it right.

Chris Adams: Okay. Thank you for that Asim. If you're new to this podcast, my name is Chris. I'm the director of technology and policy now at the Green Web Foundation, which is not the same as the Green Software Foundation. It's a small Dutch nonprofit, although we are members, founding members of the Green Software Foundation, along with a number of other much, much larger technology giants.

And I'm the host of this podcast and I'll also be doing my best to compile all the links and stories that we have so that if there's anything that has caught your interest as you listen to this, possibly whilst you're washing your dishes, you've got something to follow up with later. Alright!

Asim Hussain: Is it time for my yearly apology for naming it the Green Software Foundation and causing this constant confusion? 

Chris Adams: I think it might be, but sometimes it works in our favor as well, because when people speak to us, like a scrappy startup, a scrappy kind of wacky little non profit, then they say, "oh, we've hear...

In this episode, host Chris Adams is joined by Killian Daly, Executive Director of EnergyTag, to explore the complexities of green energy tracking and carbon accounting. They discuss the challenges of accurately measuring and claiming green energy use, including the flaws in current carbon accounting methods and how EnergyTag is working to improve transparency through time-based and location-based energy tracking. Killian shares insights from his experience managing large-scale energy procurement and highlights the growing adoption of 24/7 clean energy practices by major tech companies and policymakers. They also discuss the impact of green energy policies on industries like hydrogen production and data centers, emphasizing the need for accurate, accountable energy sourcing and we find out just how tubular Ireland can actually be!

Learn more about our people:

• Chris Adams: LinkedIn | GitHub | Website
• Killian Daly: LinkedIn | Website

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

Resources:

• GHG Protocol [09:15]
• Environment Variables Podcast | Ep 82 Electricity Maps w/ Oliver Corradi [32:22]
• Masdar Sustainable City [58:28]

If you enjoyed this episode then please either:

• 
  Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:

Killian Daly: We need to think about this kind of properly and do the accounting correctly.

And unfortunately, we don't do the accounting very well today. 

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams. 

Hello, and welcome to another edition of Environment Variables, where we bring you the latest news and updates from the world of sustainable software development. I'm your host, Chris Adams. When we write software, there are some things we can control directly. For example, we might be able to code in a tight loop ourselves, or design a system that scales to zero when it's not in use.

And if we're buying from a cloud vendor, like many of us do now, we're often buying digital resources, like gigabytes of RAM and disk, or maybe virtual CPUs, rather than physical servers. It's a little bit less direct, but we still know we have a lot of scope for the decisions, to control the impact of their decisions and what kind of environmental consequences come about from that.

However, if we look one level further down the stack, like how the energy powering our kit is sourced, our control is even more indirect. We rarely, if ever, directly choose the kind of generation that powers data centers that our code runs in. But we know it still has an impact. So if we want to source energy responsibly, how do we do it?

If you want to know this, it's a really good idea to talk to someone whose literal job for years has been buying lots and lots of clean energy and is intimately familiar with the standards involved in doing so and who has spent a lot of time thinking about how to make sure you can tell when the energy you're buying really is green.

Fortunately, today I'm joined by just that person, Killian Daly, the Executive Director of the standards organization, EnergyTag. Killian, it's really, nice to have you on the pod. Thanks for coming on.

Killian Daly: Yeah, thanks. Thanks very much for having me, Chris. great to be on the pod and, an avid listener, also. So it's always nice to contribute.

Chris Adams: Thank you very much. Killian, I'm going to give you a bit of space to introduce yourself, and I've just mentioned that you're involved in EnergyTag, and we'll talk a little bit about what EnergyTag does. Because I know you and because, well, I met you maybe three years ago, I figured it might just be, it might be worth just talking a little bit about our lives outside of green software and sustainability.

So, we were in this accelerator with the Green Web Foundation talking about a fossil free internet, and you were talking about EnergyTag and why it's important to track the provenance of energy. I remember you telling, we were asked about our passions. And, you told me about surfing and I never ever thought about Ireland as a place where you would surf because I didn't think it was all that warm. So can you maybe tell me a little bit like enlighten me here because it's not the first country I think of when I think of surfing and when you said that I was like he's" having a joke, right?"

Killian Daly: Yeah. Well, I do like to joke, but this is not actually one of the jokes, Well, it doesn't need to be warm to surf. You just need to have waves, I suppose. So, yeah, it's something since I was really very young. I've always gone to the west coast of Ireland. Beautiful County Clare near the Cliffs of Moher.

Maybe people know of them. And so we go every year. And my cousins, since a very young age, started surfing. We just, you know, solve these big waves and there's other people out there, surfing, bodyboarding and we're like, "Hey, let's try that out. That looks really cool." So, yeah, since I don't know, 6 or 7 years old, I've been going there every year, in summer, also in winter, me and my cousins also go, yeah.

We go at New Year's get into the frigid cold Atlantic. And, yeah, it's magic, really. If you have the right, if you have the right wetsuit, you can kind of, you can get through anything, 

Chris Adams: So there's no such thing as cold was it bad weather, just bad clothing that also applies to wetsuits.

Killian Daly: Yeah. Yeah. Yeah. It couldn't apply. Couldn't apply anymore. And obviously, in winter, you get the biggest swells, right? so actually, people probably don't know it, but Ireland has some of the biggest waves in the world. Now, on the west coast of Ireland, you have, yeah, really massive 50, 60 foot waves.

Yeah, really all you can get some sort of a, all time surf there. So, so yeah, it's one of one of our better kept secrets.
<...

This episode of Backstage focuses on the Impact Framework (IF), a pioneering tool designed to Model, Measure, siMulate, and Monitor the environmental impacts of software. By simplifying the process of calculating and sharing the carbon footprint of software, IF empowers developers to integrate sustainability into their workflows effortlessly. Recently achieving Graduated Project status within the Green Software Foundation, this framework has set a benchmark for sustainable practices in tech. Today, we’re joined by Navveen Balani, Srinivasan Rakhunathan, the project leads and Joseph Cook, the Head of R&D at GSF and Product Owner for Impact Framework, to discuss the journey of the project, its innovative features, and how it’s enabling developers and organizations to make meaningful contributions toward a greener future.

Learn more about our people:

• Navveen Balani: LinkedIn
• Srini Rakhunathan: LinkedIn
• Joseph Cook: LinkedIn

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

Resources:

• Impact Framework | Green Software Foundation [00:00]
• The SCI Open Ontology | Green Software Foundation [04:27]
• SCI for AI - Addressing the challenges of measuring Artificial intelligence carbon emissions | Green Software Foundation [06:57]
• SCI Guidance [12:07]
• CarbonHack [13:03]
• Impact Framework Github Page [17:58]
• IF Explorer [20:18]
• IF Community Google Group [23:42]

Events:

• Kickstarting 2025: A Community-Driven Sustainable Year (February 13 at 5:00 pm CET · Utrecht): [24:21] 
• Advocating for Digital Sustainability (February 19 at 6:00 PM GMT · Hybrid · Brighton): [25:10]
• Day 0: MeetUp Community GSF Spain (February 20 at 6:00 PM CET · Online): [25:33]
• Digging Deeper into Digital Sustainability (February 20 at 6:00 pm AEDT· Melbourne): [25:59]
• Practical Advice for Responsible AI (February 27 at 6:00 pm GMT · London): [26:27]
• GSF Oslo - February Meetup (February 27 at 5:00 pm CET · Oslo): [26:46]

If you enjoyed this episode then please either:

• Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:
Chris Skipper: Hello, and welcome to Environment Variables, where we bring you the latest news from the world of sustainable software development. I'm the producer of this podcast, Chris Skipper, and today we're excited to bring you another episode of Backstage, where we peel back the curtain at the GSF and explore the stories, challenges and triumphs of the people shaping the future of green software. We're no longer gatekeeping what it takes to set new standards and norms for sustainability in tech.

This episode focuses on the Impact Framework, also known as IF, a pioneering tool designed to model, measure, simulate, and monitor the environmental impacts of software. By simplifying the process of calculating and sharing the carbon footprint of software, IF empowers developers to integrate sustainability into their workflows effortlessly.

Recently achieving graduated project status within the Green Software Foundation, this framework has set a benchmark for sustainable practices in tech. Today, we have audio snippets from Naveen Balani, Srinivasan Rakhunathan, the project leads. And Joseph Cook, the head of R&D at GSF and product owner for Impact Framework, to discuss the journey of the project, its innovative features, and how it's enabling developers and organizers to make meaningful contributions toward a greener future.

And before we dive in, here's a reminder that everything we talk about will be linked in the show notes below this episode. So without further ado, let's dive into the first question about the Impact Framework for Naveen Balani.

Naveen, the Impact Framework has been described as a tool to model, measure, simulate and monitor the environmental impacts of software.

Could you provide a brief overview how this works and the inspiration behind creating such a framework?

Navveen Balani: Thank you, Chris. And thanks to all the listeners for tuning in. Let's first understand the problem we're solving with the Impact Framework. Software runs the world, but its environmental impact is often invisible. Every CPU cycle, every page load, every API call, these all contribute to energy consumption, carbon emissions, and water usage.

Yet, without the right tools, measuring and managing this impact remains a challenge. This is where the Impact Framework comes in. It's an open source tool designed to transform raw system metrics like CPU usage or page views into tangible environmental insights, helping organizations take action. Built on a plugin based architecture, it allows users to integrate, customize, and extend measurement capabilities, ensuring scalability and adaptability.

More importantly, the Impact Framework helps realize the software carbon intensity specification, making sustainability reporting transparent, auditable, and verifiable. Every calculation, assumption, and methodology is documented in a manifest file, ensuring that impact assessments are replicable and open for collaboration.

At its core, the Impact Framework is built on a simple yet powerful idea. If we can observe it, we can measure its impact. And once we can measure it, we can drive real change, reducing emissions, optimizing resource use and building truly sustainable software.

Chris Skipper: What were som...

In this episode, we go behind the scenes of the Carbon Aware SDK, a groundbreaking tool enabling developers to reduce software emissions by running workloads where and when energy is greenest. Featuring insights from Vaughan Knight, chair and project lead of the SDK, the episode dives into its origins, real-world applications, challenges, and milestones, including early contributions from UBS and Microsoft and its recent 1.7 release with NPM and Java libraries. Learn about how the SDK supports Software Carbon Intensity (SCI) metrics, practical examples of carbon-aware workload scheduling, and the roadmap for expanding developer resources and geolocation-based solutions.

Learn more about our people:

• Vaughan Knight: LinkedIn

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

Resources:

• Carbon Aware SDK

If you enjoyed this episode then please either:

• Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!
• Connect with us on Twitter, Github and LinkedIn!

Hosted on Acast. See acast.com/privacy for more information.

In this episode of Environment Variables, host Chris Adams sits down with Mark Bjornsgaard of Deep Green to explore a transformative approach to data center design and sustainability. Mark shares insights into how Deep Green reimagines traditional data centers by co-locating them in urban areas to provide heat reuse for facilities like swimming pools, district heating systems, and industrial processes. They discuss the challenges of planning and policy, the rise of high-density computing driven by AI, and the potential for data centers to become integral components of community infrastructure. Tune in to learn about the intersection of digital innovation and environmental responsibility, and how new business models can turn waste into opportunity.

Learn more about our people:

• Chris Adams: LinkedIn | GitHub | Website
• Mark Bjornsgaard: LinkedIn | Website

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

Resources:

• Mark Bjornsgaard on LinkedIn: Dell's OCP Solutions Propel AI Innovation [07:52]
• Civo [37:31]
• Real Time Cloud | GSF 

If you enjoyed this episode then please either:

• 
  Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:

Mark Bjornsgaard: The government does need to legislate. There is just not enough structure and there's not enough impetus for people to do the right thing. But the also, and particularly in the UK, what the government needs to do is planning is a huge, huge hurdle. I never really understood that until we'd be working with Deep Green for, you know, building data centers.

It is breathtaking how Kafka-esque the planning system in the UK is. It's just, 

It's beyond insane.

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams. Okay, Mark, a few years back, when people were asked what a data center was, if they knew what one was at all, they might talk about some kind of thing, room, cupboard full of a few machines, maybe in a rack inside a unused room inside a building, for example. But these days, in the 2020s, people are more likely to talk about a warehouse full of hyperscale kind of data servers in a building, which is maybe the size of a football field or larger, for example, the kind of things that are run by massive firms like Google, Microsoft and Amazon, for example.

Now, as I understand it, you work with data centers, too, but they can take a rather different shape and interact rather differently with the built environment. So for those who've never heard of Deep Green, or how the stuff you're doing is different, give a kind of brief introduction to like how your approach to like building data centers is and how that has an impact on how it works with the surrounding area, for example, communities.

Mark Bjornsgaard: Yeah. So, as you say, most data centers are built in the middle of nowhere, and the vast majority are built without heat reuse. So the vast majority simply eject the heat that comes out of the computers. Data centers, we know, two to four percent of the world's electricity supply, and computers themselves are incredibly efficient electric heaters.

So 97 percent of the electrons that go into a computer come out as heat. So you've got us as a species, us in a climate emergency, taking two to four percent of the world's electricity supply, converting it into heat, and then ejecting it into the atmosphere, which 10 years ago, that might have sounded kind of plausible or even sort of necessary.

But in a world, as I said, in a climate emergency, that doesn't look so clever. So the difference between Deep Green and every other data center, most other data centers is we are building the data center where the heat can be reused. So very hard to transport heat, but relatively easy to transport electrons to take the data center to where the heat's required.

So that's what we do. We build smaller data centers, co-locate them where heat's required. Now that might be a laundry, it might be a distillery, it might be food production, it might be antibiotic production, it might be a swimming pool, but more often than not, it's what's called a district heating system.

So these large centralized heat networks that through super insulated pipes supply heat to large areas of different cities. That sort of principle, that district heat systems and heat networks, we're not very good at them in the UK specifically, but we are, the government is certainly planning for us to get a lot best them in the years to come.

So, that's where we're anchored. We, you don't build them in the middle of nowhere, you build them where they're required. There's a further, there's a further caveat and a sort of, a kind of context to this, I suppose, if you'd like. Up until the point where AI started to become part of our everyday lives, those normal data centers aren't on very much.

They're only on 20, 30 percent of the time, and they don't actually generate very good waste heat. So you can certainly forgive the great, the good of the data center industry for not necessarily trying too hard to reuse heat in the old world. But in the world that's coming where we've got these incredibly dense racks of NVIDIA and other chips, where, you know, she utilising a massive, huge amount more energy than previously the datasets had.

That, it's at this point where those are on 70, 80 percent of the time, and they're generating an enormous amount of heat, and the heat's relatively high grade. It's not high grade heat as class within, but it's good low grade heat. So at this point, then the ability to reuse heat becomes a real thing. And that's why we exist.

Chris Adams: Ah, I see. Okay, so there's a couple of things I'd like ...

In this episode of Environment Variables, host Chris Adams is joined by Tammy Sukprasert, a PhD student at the University of Massachusetts Amherst, to dive deep into her research on carbon-aware computing. Tammy explores the concept of shifting computing workloads across time and space to reduce carbon emissions, focusing on the benefits and limitations of this approach. She explains how moving workloads to cleaner regions or delaying them until cleaner energy sources are available can help cut emissions, but also discusses the challenges that come with real-world constraints like server capacity and latency. Together they discuss the findings from her recent papers, including the differences between average and marginal carbon intensity signals and how they impact decision-making. The conversation highlights the complexity of achieving carbon savings and the need for better metrics and strategies in the world of software development.

Learn more about our people:

• Chris Adams: LinkedIn | GitHub | Website
• Thanathorn (Tammy) Sukprasert: LinkedIn | GitHub | Google Scholar

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

News:

• On the Limitations of Carbon-Aware Temporal and Spatial Workload Shifting in the Cloud | Proceedings of the Nineteenth European Conference on Computer Systems [03:25]
• On the Implications of Choosing Average versus Marginal Carbon Intensity Signals on Carbon-aware Optimizations | Proceedings of the 15th ACM International Conference on Future and Sustainable Energy Systems [22:12] 

Resources:

• Tammy's GitHub [19:00]
• CarbonScaler: Leveraging Cloud Workload Elasticity for Optimizing Carbon-Efficiency | Proceedings of the ACM on Measurement and Analysis of Computing Systems [33:19]

If you enjoyed this episode then please either:

• 
  Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPTION BELOW:

Tammy Sukprasert: With that one hour job with perfect knowledge of one year, we can reduce the carbon emission of the whole world by 37%.

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams. Hello, and welcome to Environment Variables. Where we bring you the latest insights and updates from the world of sustainable software development. I'm your host, Chris Adams. One of the oft repeated quotes when people talk about sustainability in software is that if you can't measure it, then you can't manage it.

And when it comes to working out the carbon footprint of a software application, a significant portion of the footprint comes from what we refer to as the carbon intensity of the electricity in use, 

i.e., how green it is. And there are various steps you can take to make the same application using the same code, you can make it greener by running it where the grid is greener. So if you were to choose to run it in Iceland, that's one example. Or you can choose to run the grid, run the application at different times when the grid is greener, like when the sun is in the sky and your solar panels are wearing away. But how much greener can they get? And what else could we need to think about when trying to adopt a ways or ideas like this? Enter our guest for this episode today, Tammy Sukprasert, a PhD student at the Laboratory of Advanced Software Systems and Sustainable Computing Lab at the University of Massachusetts Amherst.

Tammy recently authored the paper on the limitations of carbon aware, temporal, and spatial workload shifting in the cloud, which examines how shifting computing workloads across time and space can help cut emissions. Tammy, we're going to spend a bit of time talking about why you chose to work in this field.

But to begin with, can I give you a bit of space to introduce yourself and what you do?

Tammy Sukprasert: Hi, Chris. Thanks for having me here. I'm Tammy Sukprasert. I'm a PhD student from the University of Massachusetts Amherst. I work on cloud and edge computing with a specific focus of decarbonizing computing. I'm currently calling you from Amherst, Massachusetts, and it's nice out here.

Chris Adams: Cool. That's nice. We've had a, it's snowing in Berlin, so I'm a little bit jealous, actually. Hi folks. If you are new to this podcast, my name is Chris Adams. I am the Director of Technology and Policy at the Green Web Foundation. And I'm also the, one of the chairs of the Green Software Foundation Policy Working Groups.

And also, the host of this podcast. Now, before we dive into the conversation with Tammy, if you're listening to this for the first time, here's a quick reminder. We will try to link to all the papers and all the links and all the projects on GitHub in this, and there will be extensive show notes as well as a transcript if there's anything you particularly missed.

And I think that's pretty much it. Tammy, are you sitting comfortable?

Tammy Sukprasert: Yep. Nice.

Chris Adams: In that case, I guess I'll begin. All right. We've linked to this in the show notes, but the paper title, On the Limitations of Carbon Aware Temporal and Spatial Workload Shifting in the Cloud, does kind of give a clue about what this research might actually be about.

But for those who are new to this idea, would you mind bringing listeners up to speed about what workloads are, what workload shifting is, when we talk about carbon aware computing?

Tammy Sukprasert: Sure. So to understand what workload shifting is, we need to have some idea of why we can shift the workload in the first place. So carbon intensity is based on the contributions of the different energy sources in the electric grid, right? So at different point in time, the demand...

Environment Variables host Chris Adams is joined by Jo Lindsay Walton, a senior research fellow at the Sussex Digital Humanities Lab and co-author of the report The Cloud and the Climate: Navigating AI-Powered Futures. They delve into the intersection of climate and AI, exploring the environmental impact of AI technologies and the challenges of decarbonizing the ICT sector. Jo discusses key takeaways from the report, including the importance of understanding AI's direct and indirect impacts, the nuanced roles of big tech companies, and strategies for critically assessing claims of AI-driven sustainability. This insightful conversation highlights the need for interdisciplinary approaches and robust collaboration to navigate the complex relationship between technology and climate action.

Learn more about our people:

• Chris Adams: LinkedIn | GitHub | Website
• Jo Lindsay Walton: LinkedIn | Website

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

News:

• The Cloud and the Climate: Navigating AI-Powered Futures [01:15]
• Microsoft files patents for carbon capture and grid-aware workload scheduler - DCD [07:54] 
• Potential of artificial intelligence in reducing energy and carbon emissions of commercial buildings at scale | Nature Communications [16:30]

Resources:

• Digital Humanities Climate Coalition | Data Culture & Society [02:08]
• Breakdown of carbon dioxide, methane and nitrous oxide emissions by sector - Our World in Data [10:29]
• The climate impact of ICT: A review of estimates, trends and regulations [10:51]

If you enjoyed this episode then please either:

• 
  Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:

Jo Lindsay Walton: There's this great metaphor that Arvind Narayanan and Sayash Kapoor have in their book, AI Snake Oil. They say, "imagine we just talked about vehicles. We didn't talk about bicycles or cars or buses or trains. And we tried to talk about the climate impact of vehicles." It would be very difficult to do.

And that's essentially what AI discourse does, right?

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams. Hello, and welcome to Environment Variables, where we bring you the latest news and updates from the world of sustainable software development. I'm your host, Chris Adams. Like seemingly everyone else in the industry, we've been talking about AI a fair amount recently, and earlier this year, in September, the Sussex Digital Humanities Lab published their report, The Cloud and the Climate, Navigating AI Powered Futures.

It's not a small report, weighing in at around 190 pages, and it has a number of key messages we'll be exploring in this episode. Also, one of the previous guests from back in September, 2023, Jo Walton was one of the authors of this report, and he was a nice enough to make some time to join us today on the pod.

So, Jo, thank you so much for coming onto the pod again. Can I give you a bit of time to introduce yourself and what you do in your day to day for people who missed the last episode back in September?

Jo Lindsay Walton: Hello. Yes. Thanks. Thanks so much for having me. So I'm a senior research fellow in arts, climate, and technology at the Sussex Digital Humanities Lab. My day to day is 90 percent playing with my cat, but I am also part of the Digital Humanities Climate Coalition and the newly launched Climate Acuity Initiative, which does facilitation and CPD training around climate and tech in hopefully fun ways involving storytelling and games and things like that.

And yeah, it's just, it's really nice to be back on this wonderful podcast. I feel like the host of SNL.

Chris Adams: Thanks. So, just before I check, when you say CPD, CPD is continuous professional development. People who want to build understanding of climate into their professional life, right? Is that what it is?

Jo Lindsay Walton: Yeah, that's it. Exactly. And it's, really I guess, part of my work is at the intersection of climate and technology, but I'm not personally super technical. Most of your listeners probably have a lot more technical knowledge than I do. What I am really interested in is communicating around these issues and education as well.

So I'm raising them for all the stakeholders for whom they might be important.

Chris Adams: Brilliant. Okay. And, on the subject of other three letter acronyms, I've just had my cat walking myself, so if it walks across the, when we're recording, please do forgive it. It's just, that's what he does sometimes. Okay. Folks, if you are listening and you've never heard my voice before, I am Chris Adams.

I am the executive director of the Green Web Foundation, which is one of the members of the Green Software Foundation. The Green Web Foundation is a nonprofit based in the Netherlands, focused on reaching an entirely fossil free internet. By 2030, I also work as one of the policy working group chairs inside the policy work in, inside the GSF, as well as being the host on this podcast as well.

All right, then. So just before we dive in, if we speak about a particular paper or a report or a link, we will add these in the show notes. And if you, if there's something you're missing, please do send us an email or get in contact us because we do our best to keep these available and like useful resources for people.

All right, then. Jo, are you sitting comfortably?

Jo Lindsay Wal...

In this episode of Environment Variables, Anne Currie welcomes Carlos Pignataro, a leading expert in sustainable network architecture, to explore how networks can balance energy efficiency with performance and resilience. Carlos shares insights from his career at Cisco and beyond, including strategies for reducing emissions through dynamic software principles, energy-aware networking, and leveraging technologies like IoT and Content Delivery Networks (CDNs). They discuss practical applications, the alignment of green practices with business interests, and the role of multidisciplinary collaboration in driving innovation. Tune in for actionable advice and forward-thinking perspectives on making networks greener while enhancing their capabilities.

Learn more about our people:

• Anne Currie: LinkedIn | Website
• Carlos Pignataro: LinkedIn | Website | GSF Champion | IETF Profile

Find out more about the GSF:

• The Green Software Foundation Website 
• Sign up to the Green Software Foundation Newsletter

News:

• Challenges and Opportunities in Management for Green Networking [16:50]
• Architectural Considerations for Environmental Sustainability [22:22]
• Sustainable Network Operations (SNO) [13:54]
• Environmental Sustainability Terminology and Concepts [20:03]

Resources:

• IETF [24:21]
• Internet Research Task Force (IRTF) [24:54]
• E-Impact Workshop | GitHub
• Green Software Practitioner

If you enjoyed this episode then please either:

• 
  Follow, rate, and review on Apple Podcasts
• Follow and rate on Spotify
• Watch our videos on The Green Software Foundation YouTube Channel!

Connect with us on Twitter, Github and LinkedIn!

TRANSCRIPT BELOW:

Carlos Pignataro: Many of the things that we do with a little bit of spin, hugely benefit the bottom line by cutting down costs, hugely benefiting the world by lowering emissions. I'm going to run this batch job whenever there's renewable. I'm going to turn off the lights and the APL, the access points on the ceiling automatically when there's no presence.

Basic things that make a difference.

Chris Adams: Hello, and welcome to Environment Variables, brought to you by the Green Software Foundation. In each episode, we discuss the latest news and events surrounding green software. On our show, you can expect candid conversations with top experts in their field who have a passion for how to reduce the greenhouse gas emissions of software.

I'm your host, Chris Adams.

Anne Currie: Hello, and welcome to Environment Variables, where we bring you the latest news and updates from the world of sustainable software development. I'm your host, Anne Currie, and today we're joined by Carlos Pignataro, a leading voice in sustainable network architecture. Carlos has over 20 years of experience in technology, innovation, and strategic thinking, holding key roles at Cisco, including head of technology and data for Cisco's engineering sustainability.

Currently, he's a mentor in residence at Duke University New Ventures, adjunct facility member at NC State University. And he is the founder and principal at Blue Fern Consulting. In this episode, we'll dive into Carlos' work on architecting networks for environmental sustainability. He's contributed to cutting edge research on how networks, which are critical to our connected lives, can balance energy efficiency with performance and resilience.

How can the networking industry innovate without compromising the planet? What trade-offs do we have to consider? Things like uptime, speed, against, or as well as, environmental responsibility. Let's explore these questions and more with Carlos. So welcome Carlos. Can you tell us a little bit about yourself?

Carlos Pignataro: Thank you very much, Anne. I am so excited to be here, first of all, and I'm happy to tell you a little bit about myself, even though you covered a lot, that was a very kind intro. I appreciate it. My favorite number is 27. My favorite color is aquamarine, just for completeness. But on a more, on an equally serious note, Important for my introduction is to say that I have passions for technology and for sustainability.

And I look at tech as a means to an end and making things better is one of the ends. I've been involved, as you said, as you mentioned in building networks, computer networks, internet infrastructure, data centers. I have also been involved in other uses of technology, such as technoconservation or conservation technologies, protecting endangered species, such as rhinos in different countries in Africa or in India from poaching using IOT, Internet of Things technology, I've been involved in building data models and information models for recycling and overall circularity. So I try to build my overall experiential breadth through trying different aspects of technology and sustainability is one on which I'm super passionate about.

Anne Currie: Excellent. That's very good to hear. And that's why you're here today. So just a little bit about myself, because I'm not always the host. I'm a guest host for Environment Variables. My name is Anne Currie. I am, I've been in the tech industry for about 30 years. I am one of the co authors of O'Reilly's new book, Building Green Software, which covers a lot of, actually covers a lot of what Carlos and I will be talking about today, cause there is a networking chapter in it.

And I strongly recommend it to everybody who's listening to the podcast. I am also the CEO of learning and development company, Strategically Green. We do a lot of workshops to help people push knowledge and engagement with green subjects within their own businesses. So touch me up on LinkedIn if you're interested in that kind of thing.

So before we start in, we dive into today's content is a rem...