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Green IO London
No AI without APIs
Apidays London and Green IO have partnered to bring you the latest insights from thought leaders in Tech Sustainability and hands-on feedback from practitioners scaling Green IT. Great hopes ha...
September 30 to 1, 2026
Convene Sancroft, St. Paul's, London
Call for speakers is now open!
If you wish to share your experience about reducing the environmental footprint of Tech.
Why they attended our past London editions
“Thanks again for inviting me to join the panel discussion at GreenIO. The energy and passion in the room was brimming which is always very encouraging! Great job on such a successful event.”
Lydia Tabbron, Digital Sustainability Lead (DEFRA)“This was my second year at Green IO and I was so honoured to be on stage for a second year as well and the growth, and bigger stage! gave me goosebumps. I walked away inspired and having learnt things that we’ll be applying to our own digital sustainability projects. But mainly the sense of community that I felt at the conference was incredible and uplifting and it has inspired me to reignite getting more involved in the wider digital sustainability community as well.”
Andri Johnston, Digital Sustainability Lead (Cambridge University Press and Assessment)“I’m not new to sustainability, yet I am fairly new to finding like-minded people to talk to about it. My entry points were my local Green Software and GreenSEO meetup groups. So, coming to Green IO, I knew there were some good speakers, but I didn’t know what to expect in terms of vibe. How brilliantly surprised I was! This is not your standard corporate sales-fest; Green IO is the real deal. A conference full of people doing work they care about for the good of the planet – I’ve found my clan and I’ll be back!”
Fiona MacNeill, Director - UX (Research & Strategy, Macknowlogist)Agenda of the last edition
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Day 1 (Workshop Day)
Tuesday 23rd September 2025
14:00 to 14:25WorkshopSee moreData-driven decisions that maximise Cloud and AI sustainability. A GreenOps deep dive by engineers, for engineers and CTO's
See what is behind the technology that enables customers like Mastercard cut hundreds of MtC02 and reduce spend by miliions of dollars. Focus on coverage for AI - proactive data-driven actions to deal with the tsunami of cost and GHG emissions. Plus, best practice use of ISO 14064 GHG data in the platforms that engineers, FinOps practitioners and IT Sustainability teams use. Presentation slidesIn collaboration with
14:25 to 14:50WorkshopSee moreICT & cloud footprint data at scale: an API for digital sustainability through LCA
This workshop introduces participants to Resilio DB an industry-leading footprint database forLife Cycle Assessment (LCA) of digital product & services. Designed to overcome the challenges ofperforming LCAs at scale Resilio DB API provides reliable & easy to use consistent footprint data for the ICT sector. Participants will first explore the web UI before gaining hands-on experience with the REST APIendpoints through a guided Postman collection. You'll learn how to leverage Resilio DB tosearch and assess various digital devices from servers/VMs to end-user devices or customconfigurations.In collaboration with
14:50 to 15:15WorkshopSee moreMitigating the environmental & social costs of AI projects in large organisations : stakes, limitations & approaches
AI is reshaping every business process, yet its rise brings high environmental costs, ethical concerns and organisational risks. In this session, we’ll explore the scale of limitations and how to handle uncertainty; you’ll also learn how to empower project and digital teams with the right methods and tools to adopt a sustainable approach and actively manage the environmental footprint of AI projects while ensuring alignment with best practices. Results: you'll not only promote compliance, but also trust, savings and resilience, transforming sustainability from a constraint into a lever.In collaboration with
15:15 to 15:40WorkshopSee moreBeyond the Digital Sustainability Bubble – Nudging Strategic Change in 90 Days
Digital sustainability is moving up the agenda but often feels complex or overshadowed by other priorities. Climate Fresk workshops have been effective for raising awareness, yet many participants struggle to translate insights into practical steps. To bridge this gap, we designed a 90-minute plug-in for the Action phase, using a card-based digital product lifecycle. Teams map sustainability directly to their projects, explore practical choices, and identify co-benefits like lower costs or improved user experience. The session ends with three clear commitments, making change both tangible and trackable. Feedback has been consistently positive, showing this approach helps embed sustainability into everyday digital work.In collaboration with
15:40 to 16:05Coffee Break & Networking
16:05 to 16:3016:30 to 16:55WorkshopSee moreApp growth meets infra reality: The GreenOps advantage
As the number of applications and their complexity grows, so do financial and environmental costs. While organizations have traditionally relied on FinOps to manage spending, Sopht will discuss how GreenOps brings an infrastructure-level perspective, optimizing both cost and carbon impact. Sopht will illustrate this by showcasing how its product GreenAPP enables actionable insights and measurable results. Magali Saúl oversees the international expansion of Sopht in the UK and in Germany. Her career reflects a strong dedication to sustainable development. She is a passionate supporter of tech-for-good solutions and their potential to drive transformative change.In collaboration with
16:55 to 17:20WorkshopSee moreWhy IT footprint assessment is not enough to begin with? The importance of employees’ culture.
IT footprint assessment is essential but not enough. Numbers on CO₂ or kWh are useful but rarely change behaviours or foster long-term engagement. True transformation requires a Sustainable IT culture built on governance, procurement, awareness, training and communication. Organizations must also create a Green IT strategy, aim for the Sustainable IT label and rely on predictive models to anticipate future footprint and costs. This proactive approach drives resilience, trust and long-term cost savings, while aligning IT with broader climate goals and stakeholder expectations.In collaboration with
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Day 2 (Conference Day)
Wednesday 24th September 2025
09:30 to 09:55OPENING REMARKSSee moreIn praise of the question mark: a journey from Descarte to ChatGPT
09:55 to 10:20KeynoteSee moreForget SkyNet, will the energy consumption of AI destroy humanity? What can developers learn from Sarah Connor?
What's going to stop giant AI data centres from turning the clock back on the energy transition and killing us all? Anne Currie, tech veteran and co-author of O'Reilly's Building Green Software, will ask where we are now, how we got here, and what AI strategies are being pursued by organisations and governments worldwide. Some of those strategies are designed to produce AI that will be aligned with humanity and the planet and some are not. How do we make sure the goodies win? There is no fate but what we make. Presentation slides10:20 to 10:4510:45 to 11:15Coffee Break & Networking
11:15 to 11:40TalkSee moreGood for the Planet, good for the wallet: how AI can heat our water
We've been talking about re-using heat from data centres for 15 years - why so little progress? Charlie Beharrell from heata delves into the opportunity in heat reuse and the underlying barriers to adoption. He presents heata's vision for a new kind of digital infrastructure that is more efficient, ethical, and faster to build. Charlie will be joined on stage by Mark Buss, Digital Sustainability Manager at OVO Energy, to present results from their recent collaboration. Presentation slides11:40 to 12:05TalkSee moreSustainable CI/CD: shifting compute tasks where CO2 intensity is the lowest
Developers don’t need to wait for data centers in space to reduce their impact, we can start today. This talk explores how to make CI/CD and AI workloads more sustainable by shifting jobs to cleaner, lower-carbon regions in real time. Learn how to move beyond price and performance by adding sustainability and resilience as first-class priorities, cutting emissions by up to 90%, lowering cloud costs, and enabling multi-cloud resiliance. From GitHub Actions to decentralised networks like Heata, this is a practical look at the future of compute. Presentation slides12:05 to 12:30TalkSee moreMastercard are saving millions of dollars and hundreds of MTC02. Now it is time for UK-driven success.
How to Unlock the Double-Wins of Cloud Sustainability. Using real-life case-studies, this session explores how enterprise cloud users can deliver cloud optimisation initiatives which deliver business value, driven by GreenOps data. This session will share UK and global use cases driven from the UK, including NTT Data and Cambridge University Press. This includes Sustainable AI, a rapidly growing pressure on cost and emissions targets. Presentation slides12:30 to 12:55Panel DiscussionSee moreCan networks keep up with the AI boom? A 2030 discussion
12:55 to 14:00Lunch Break & Networking
BOOK SIGNINGSee moreBook Signing: "Building Green Software"
14:00 to 14:25Panel DiscussionSee moreImplementing Gov AI playbook: trade-off from the trenches
14:25 to 14:50TalkSee more3 concrete success stories from DEFRA
14:50 to 15:15TalkSee moreClick, log in, carbon down: the sustainability journey of GOV.UK One Login
Every click, login, and line of code carries a carbon cost — yet ICT emissions already exceed aviation and cement, and they’re rising fast. To meet Net Zero, digital sustainability must become a core principle, not an afterthought. In this session, Jennifer Marks, Head of Digital Sustainability at the Department for Science, Innovation & Technology, shares how GOV.UK One Login pioneered greener digital services. From developing a new emissions methodology to collaborating with startups and using data to drive cultural change, the team proved that even small shifts can deliver big impact. Join to hear candid insights, practical lessons, and how sustainability can stand alongside security and accessibility as a core requirement for digital government. Presentation slides15:15 to 15:40TalkSee moreClimate change is here - using a systems thinking approach to keep NHS resilient
Join Ben Tongue, Greener Digital Lead for NHS and Claire Robinson, Sustainable Business Director for TransformUK as they share a new Proof of Concept - using Systems Mapping to understand how to maintain resilient digital services in the face of climate risks and events like heatwave. They’ll share a live visualisation, learnings on the vulnerabilities of digital services, and key interventions to improve resilience across supply chains: from healthcare professionals to procurement, to actors across data, software, network, telecoms, data centres, energy and water providers and local authorities. Presentation slides15:40 to 16:05Coffee Break & Networking
16:05 to 16:30TalkSee moreHow carbon.txt enables transparency across Tech companies
In it Hannah will explain: - The problem this project addresses - the difficulty in finding and using sustainability data that is already published into the public domain. - The web-first, connect not collect approach that underpins how it works and how it is designed to be extended by default. - How people can get involved and contribute to what we’re doing Presentation slides16:30 to 16:55TalkSee moreSCI for Web. How we applied the Software Carbon Intensity (ISO 21031) standard to the web
16:55 to 17:20TalkSee moreGreen IT is good but it's not enough!
17:20 to 17:30Closing remarks
17:30 to 20:00Green IO Happy Hours
Meet our partners
Members of the London Green IT ecosystem as well as our corporate partners will be available to exchange with you on how to accelerate your digital sustainability journey.
Global Non Profit
"The blossoming of tools and initiatives in greening IT is a heart-warming signal from the digital sector. More than ever sharing experience and insights is pivotal for actors to ramp-up their effort."
Gaël Duez
Green IO Founder
About Apidays
Apidays is the world's leading series of API conference. In today’s intricate digital landscape, APIs have emerged as powerful conduits for innovation, bridging the gaps and unlocking new realms of possibility.
