It’s been three years of Environment Variables! What a landmark year for the Green Software Foundation. From launching behind-the-scenes Backstage episodes, to covering the explosive impact of AI on software emissions, to broadening our audience through beginner-friendly conversations; this retrospective showcases our mission to create a trusted ecosystem for sustainable software. Here’s to many more years of EV!

TRANSCRIPT BELOW:
Chris Skipper: Welcome to Environment Variables from the Green Software Foundation. The podcast that brings you the latest in sustainable software development has now been running for three years.

So that's three years of the latest news in green software, talking about everything from AI energy through to the cloud, and its effect on our environment and how we as a software community can make things better for everybody else.

This past year Environment Variables has truly embodied the mission of the Green Software Foundation, and that's to create a trusted ecosystem of people, standards, tools, and best practices for creating and building green software. Now this episode's gonna feature some of the more key episodes that we did over the last year.

We're gonna be looking at a wide variety of topics and it's going to be hopefully a nice journey back through both the timeline of the podcast, but also the landscape of green software over the last year and how it has dramatically changed, not only due to the dramatic rise in use of AI amongst other things, but also just to the fantastic ideas that people have brought to the table in order to try and solve the problem of trying to decarbonize software. So without further ado, let's dive in to the first topic.

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Chris Skipper: First, we brought about a new change in the way the podcast was structured. A new type of episode called Backstage.

Backstage is basically a behind the scenes look at the Green Software Foundation, internal projects and working groups. It's a space for our community to hear directly from project leaders to share the wins and their lessons learned and reinforce trust and transparency, which is one of the core tenets of the Green Software Foundation Manifesto.

Now, there were a bunch of great projects that were featured over the last year. We're gonna look at two specifically.

In our first backstage episode, we introduced the TOSS project. TOSS stands for Transforming Organizations for Sustainable Software, and it's led by the fantastic Pindy Bhullar. This project aims to embed sustainability into business strategy and operations through a four pillar framework.

. It's a perfect example of how the foundation operationalizes its mission to minimize emissions by supporting organizations on their sustainability journey.

Let's hear the snippet from Pendi explaining these four pillars.

Pindy Bhullar: Transforming organizations for sustainable software is the acronym for toss. Businesses will be able to utilize the toss framework as a guide to lay the groundwork for managing change and also improving software operations in the future, software practices within organizations can be integrated with sustainability in a cohesive and agile manner, rather than addressing green software practices in an isolated approach.

For a company to fully benefit from sustainable transformation of their software development processes, we need to review all aspects of technology. The Toss framework is designed to be embedded across multiple aspects of its business operations. Dividing the task framework along four pillars has allowed for simultaneous, top down and bottom up reinforcement of sustainable practices, as well as the integration of new tools, processes, and regulations that I merge over time.

The four pillars aim to foster a dynamic foundation for companies to understand where to act now, to adjust later and expand within organizational's sustainable software transformation. The four pillars are strategy, implementation. Operational compliance and regulations and within each of the pillars, we have designed a decision tree that will be constructed to guide organizations in transforming their software journey.

Chris Skipper: Some fantastic insights from pindi there, and I'm sure you can agree. The Toss project has an applicability outside of just software development. It's one of those projects that's really gonna grow exponentially in the next few years. Next up, we have green software patterns. Green software Patterns Project is an open source initiative designed to help software practitioners reduce emissions by applying vendor neutral best practices. Guests, Franziska Warncke and Liya Mathew; project leads for the initiative discussed how organizations like Aviva and MasterCard have successfully integrated these patterns to enhance software sustainability. They also explored the rigorous review process for new patterns, upcoming advancements, such as persona based approaches and how developers and researchers can contribute to the project.

That's one thing to remember about Backstage is actually highlights that there are so many projects going on at the GSF. We actually need more people to get involved. So if you are interested in getting involved, please Visit greensoftware.foundation to find out more. Let's hear now from Liya Mathew about the Green Software Patterns Project.

Liya Mathew: One of the core and most useful features of patterns is the ability to correlate the software carbon intensity specification. Think of it as a bridge that connects learning and measurement. When we look through existing catalog of patterns, one essential thing that stands out is their adaptability.

Many of these patterns not only aligned with sustainability, but also coincide with security and reliability best practices. The beauty of this approach is that we don't need to completely rewrite a software architecture. To make it more sustainable. Small actions like catching static data or providing a dark mode can make significant difference.

These are simple, yet effective steps that can lead us a long way towards sustainability. Also, we are nearing the graduation of patterns V one. This milestone marks a significant achievement and we are already looking ahead to the next exciting phase. Patterns we two. In patterns we two, we are focusing on persona based and behavioral patterns, which will bring even more tailored and impactful solutions to our community.

These new patterns will help address specific needs and behaviors, making our tools even more adaptable and effective.

Chris Skipper: Moving on. We also kept our regular episode format The Week in Green Software, also known affectionately as Twigs. So Twigs was originally hosted by Chris Adams and is now occasionally hosted by the Fabulous and Currie as well.

It offers quick actionable updates in the green software space with a rising sustainability news. With a rising tide of sustainability and AI developments, this format helps listeners stay current. I can tell you now that in the last year, the number of news topics has just exploded when it comes to anything to do with AI and the impact it's having on the environment.

And I think part of that is due to the work of the GSF and its community members. We used to have to really struggle to find news topics when this podcast first started back in 2022. But now in 2025, every week, I would say nearly every hour, there's a new topic coming out about how software is affecting the environment.

I. So The Week in Green Software is your one stop place for finding all that information dialed down into one place. And also you can sign up to the GSF newsletter as well via the link below, which will give you a rundown of all the week's latest new topics as well. So let's look at a couple episodes of twigs from the previous year.

The first one is an episode with the executive director of the GSF Asim Hussain. Asim really embodies the mission of the GSF in so many ways and is always passionate about the effect that software is having on the environment. In this episode, which was subtitled, Obscuring AI's Real Carbon Output , Asim joined Chris to unpack the complexities of AI's, carbon emissions, renewable energy credits, and regulatory developments.

This episode emphasized the need for better carbon accounting practices; work the foundation is helping to advance. Let's hear this little snippet from Asim now.

Asim Hussain: You can plant a tree, right? And then you planted the tree. That tree will grow and there's issue there. This drought tree will grow and it'll suck carbon from the atmosphere. And you can say that's a carbon credit at planting a tree. Or there's carbon avoidance offsets and there's many variant, and that's actually very good variance of carbon avoidance offsets.

But there is a variant of a carbon avoidance offset where I've got a tree and you pay me not to cut it down. And so where is the additionality? If I'm actually planting a tree, it's happening and planting a tree. I'm, I'm, I'm adding additional kind of capacity in, in carbon removal. And then the renewable energy markets is exactly the same.

You can have renewable energy, which if you buy means a renewable power plant is gonna get built and you can have renewable energy, which is just kind of sold. And if you buy it or you don't buy, there's no change. Nothing's gonna happen. There's no more new renewable plant's gonna get built. Only one of them has that additionality component.

And so therefore, only one of them should really be used in any kind of renewable energy claims. But both of them are allowed in terms of renewable energy claims.

Chris Skipper: One of the things I love about the way Asim talks about software in general is always, he uses idioms like that planting of a tree to explain a real complex, uh, topic and make it more palatable for a wider audience, which is something that we're gonna explore later on in this episode as well. But before we do that, let's move on to another episode of The Week in Green Software, which was subtitled Sustainable AI Progress.

I think you can see a theme that's been going on here. This was our hundredth episode, which was a massive milestone in its own, and the Fantastic Anne Currie hosted Holly Cummins to explore light switch ops, zombie servers, and sustainable cloud architecture. This conversation. Perfectly aligns with the foundation's mission to minimize emissions through smarter, more efficient systems, and having the really knowledgeable, brilliant.

Holly Cummins on to talk about light switch ops was just fantastic. , Let's listen to this next clip from her talking about light switch ops.

Holly Cummins: We have a great deal of confidence that it's reliable to turn a light off and on, and that it's low friction to do it. And so we need to get to that point with our computer systems and, and you can sort of, uh, roll with the analogy a bit more as well, which is in our houses, it tends to be quite a manual thing of turning the lights off and on.

You know, I, I, I, you know, I. Turn the light on when I need it. In institutional buildings, it's usually not a manual process to turn the lights off and on. Instead, what we end up is we end up with some kind of automation. So like often there's a motion sensor. So, you know, I used to have it that, um, if I would stay in our office late at night.

At some point if you sat too still because you were coating and deep in thought, the lights around you would go off and then you'd have to like wave your arms to make the lights go back on. And it's that, that, you know, it's this sort of idea of like, we can detect the traffic, we can detect the activity and not waste the energy.

And again, we can do. Exactly this with with our computer system so we can have it so that it's really easy to turn them off and on. And then we can go one step further and we can automate it and we can say, let's script to turn things off at 5:00 PM because we're only in one geo

Chris Skipper: So as you can see, there's always been this theme of Rise in AI, you know, and I think everybody who's involved in this, uh, community and even people outside of it are really kind of frightened and scared of the impact that AI is having on the environment. But one thing that the GSF brings is this anchoring, this hope that there is actually change for the better.

And there are people who are actively working against that, within the, within the software industry. And. There's, there's actually gonna be a lot of change coming in the next year, which will make things a lot more hopeful, uh, for the carbon output of the software industry. So between 2024 and 2025 AI's impact on the environment became one of the most discussed topics in our industry, and obviously on this podcast.

In 2023 alone data center, electricity consumption for AI workloads was estimated to grow by more than 20%. With foundation models like ChatGPT four, using hundreds of megawatt hours per training run,

obviously there are a lot of statistics out there that are quite frightening, but hopefully Environment Variables brings you some peace of mind. And with that, we wanted to expand our audience to a wider group of people that weren't just software developers to make things more palatable for your everyday computer user, for example. ,

So one of those episodes that we're gonna feature around that move to try and increase our audience growth is an episode called AI Energy Measurement for Beginners, where Charles Tripp and Dawn Nafus helped us break down how AI's energy use is measured and why it's often misunderstood.

Their beginner friendly approach supports one of the GFS key goals, which is making green practices more accessible And inclusive. Here is Charles talking about one of those points in this next snippet.

Charles Tripp: I think there's a, there's like a historical bias towards number of operations because in old computers without much caching or anything like this, right? Like, uh, I, I restore old computers and, um, like an old 3 86 or IBM xt, right? Like it's running, it has registers in the CPU and then it has main memory and it, and almost everything is basically how many operations I'm doing is going to.

Closely correlate with how fast the thing runs and probably how much energy it uses, because most of the energy consumption on those systems is, is just basically constant no matter what I'm doing. Right. Yeah. It's just, it doesn't like idle down the processor while it's not working. Right. There's a historical bias that's built up over time that like was focused on the, the, you know, and it's also at the programmer level.

Like I'm thinking about what is the, the computer doing? What do I have control over? Yeah. What's, what, yeah. One, am I able to, but it's only through, it's only through actually measuring it that you gain a clearer picture of like what is actually using energy. Um, and I think if you get that picture, then you'll gain, um, uh, uh, an understanding more of.

How can I make this software or the data center or anything in between, like job allocation, more energy efficient, but it's only through actually measuring that we can get that clear picture. Because if we guess, especially using kind of our biases from how we, how we learn to use computers, how we learn about how computers work, we're actually.

Very likely to get an incorrect understanding, incorrect picture of what the, what's driving the energy consumption. It's much less intuitive than people think.

Chris Skipper: thanks to Charles for breaking it down in really simple terms and for his contribution to the podcast. Another episode that tried to simplify the world of AI and the impact that it's having on the environment is called the economics of ai, which we did with Max Schultze.

He joined us to talk about the economics of cloud infrastructure and ai. He challenged the idea that AI must be resource intensive arguing instead for clearer data, stronger public policy, and greater transparency, all values that the GSF hold dear. Let's listen to that clip of Max talking about those principles.

Max Schulze: I think when as a developer you hear transparency and, okay, they have to report data. What you're thinking is, oh, they're gonna have an API where I can pull this information. Also, let's say from the inside of the data center now in Germany, it is also funny for everybody listening one way to fulfill that because the law was not specific.

Data centers now are hanging a piece of paper. I'm not kidding. On their fence with this information, right? So this is like them reporting this. And of course we as, I'm also a software engineer, so we as technical people, what we need is the data center to have an API that basically assigns the environmental impact of the entire data center to something.

And that something has always bothered me that we say, oh, it's the server or it's the, I don't know, the rack or the cluster, but ly. What does software consume? Software consumes basically three things. We call it compute, network, and storage, but in more philosophical terms, it's the ability to store, process and transfer data.

And that is the resource that software consumes. A software does not consume a data center or a server. It consumes these three things. Mm-hmm. And a server makes those things turns actually energy and a lot of raw materials into digital resources. Then the data center in turn provides the shell in which the server can do that function, right?

It, it's the factory building, it's the data center. The machine that makes the T-shirts is the server and the t-shirt is what people wear.

Chris Skipper: Again, it's those analogies that make things easier for people to understand the world of software and the impact it's having on the environment. Also, with that idea of reaching a broader audience, we try to also talk about the energy grid as well as software development as those two things are intrinsically linked. So one of the episodes that we wanna feature now is called How To Tell When Energy Is Green with Killian Daly.

Killian explained how EnergyTag is creating a standard for time and location-based energy tracking. Two topics that we've covered a lot on this podcast. This work enables companies to make verifiable clean energy claims, helping build trust across industries. Let's listen to this clip from Killian.

Killian Daly: Interestingly, uh, actually on the 14th of January, just before, uh, um, the inauguration of Donald Trump, uh, as US president, so the Biden administration issued an executive order, which hasn't yet been rescinded, um, basically on, uh, data centers, on federal lands. And, and in that they do require these three pillars.

Uh, so they, they do have a three pillar requirement on, uh, on electricity sourcing, which is very interesting, right? I think that's. Quite a good template. Uh, and I think, you know, we definitely need to think about like, okay, if you're gonna start building loads of data centers in Ireland, for example, Ireland, uh, 20%, 25% of electricity consumption in Ireland is, is from data centers.

That's way more than anywhere else in the world in relative terms. Yeah, there's a big conversation at the moment in Ireland about like, okay, well how do we make sure this is clean? How do we think about, um, uh, procurement requirements for building a new data center? That's a piece of legislation that's on being written at the moment.

And how do we also require these data centers to do reporting of their emissions once they're operational? So the Irish government, uh, is also putting together a reporting framework for data centers and the energy agency. So the. Sustainable Energy Authority of Ireland, SEAI, they published a report a couple of weeks ago saying, yeah, they do, you know what they need to do this hourly reporting based on, uh, contracts bought in Ireland.

So I think we're seeing already promising signs of, of legislation coming down the road in, um, you know, in other sectors outside of hydrogen. And I think data centers is, is, is probably an obvious one.

Chris Skipper: Fantastic clip there from Killian. It also highlights how the work that the GSF is having is having an impact on the political landscape as well in terms of public policy and the discussions that are having in the higher ups of governments.

Moving on. We wanna talk about our final episode that we wanna highlight in this episode from the last year, and that's the episode, How to Explain Software to Normal People with James Martin. We ended the year with this episode with James, who talked about strategies for communicating digital sustainability to non-technical audiences, which is something that we try to do here at Environment Variables too. From Frugal AI to policy advocacy, this episode reinforced the power of inclusive storytelling. Let's listen to this clip from James Martin.

James Martin: A few years ago, the, the French Environment Minister said people should stop, uh, trying to send so many, uh, funny, funny email attachments, you know? Oh, really? Like, like when you send a joke, a jokey video to all your colleagues, you should stop doing that because it's, it's not good for the planet. It honestly, the, uh, minister could say something that misguided, because that's not.

We, you and I know that's not where the impact is. Um, the, the impact is in the cloud. The impact is in, uh, hardware. So instead of, it's about the, the, the communication is repetition and the, the, the, I always start with digital is 4% of global emissions. 1% of that is, is data centers. 3% of that is hardware and software is sort of.

They're sort of all over the place. So that's the, the, the thing I, that's the figure I use the most to get things started. And I think the, the number one misconception that people need to get their heads around is the people tend to think that tech is, uh, immaterial. It's because of expressions like the cloud.

It just sounds. Like, is this floaty thing rather than massive industry? Ethereal. We need to make it, we need to make it more physical. If, uh, I can't remember who said that if, if data centers could fly, then it would, it would make our, our job a lot, a lot easier. Um, but no, that, that's why you need to always come back to the figures.

4% is double, uh, the emissions of planes. And yet, um. The airline industry gets tens of hundreds times more hassle than the tech industry in terms of, uh, trying to keep control of their, of their emissions. So what you need is a lot more, uh, tangible examples and you need people to, to explain this impact over time.

So you need to move away from bad examples like. Funny email attachments or The thing about, um, the keep hearing in AI is, uh, one, one chat GBT prompt is 10 times more energy than Google. That may or may not be true, but it's a bit, again, it's a bit of the, it's the wrong example because it doesn't, it doesn't focus on the bigger picture and it can Yeah, it kind of implies, yeah, and it can make people, if I just, if I just like reduce my, my, my usage of this, then I'm gonna have like 10 times the impact I'm gonna.

You know, that's all only too, that feels a bit kind of individual in a bit like individualizing the problem. Surely it does, and, and it's putting it on people's, it's putting the onus on the users, whereas it's, once again, it, it's not their fault. You need to see the bigger picture. And this is what I've, I've been repeating since I wrote that, uh, that white paper actually, you can't say you have a green IT approach if you're only focusing on data centers, hardware or software.

You've got to focus. Arnold all three, otherwise. Yeah, exactly. Holistically

Chris Skipper: With that, we've come to the end of this episode. Well, what a year it's been for Environment Variables, and we'll just take a look at some of the statistics.

Just to blow our own horn here a little bit. We've reached over 350,000 plays. Engagement and followers to the podcast have gone up by 30%, which indicates to us that Environment Variables really matters to the people that listen to it. And it's raising awareness to the need to decarbonize the software industry.

Looking ahead. We remain committed to the foundation's vision of changing the culture of software development.

So sustainability is as fundamental as security or performance. Year four, we'll bring new stories, new tools, new opportunities, new people hopefully and all in an effort to reduce emissions together. So thank you for being part of our mission, and here's to another year of action advocacy and green software innovation.

And now to play us out is the new and improved Environment Variables podcast theme.

 Hey everybody. Thanks for listening. This is Chris, the producer again, just reaching out to say thank you for being a part of this community and a bigger part of the GSF as a whole. If you wanna listen to more episodes of Environment Variables, please head to podcast.greensoftware.foundation to listen to more,

or click the link below to discover more about the Green Software Foundation and how to be part of the podcast as well.

And if you're listening to this on a platform, please click follow or subscribe to hear more episodes of Environment Variables.

We'll catch you on the next one. Bye for now.