Green IO London 2026: Where Practitioners Decarbonise the Stack

Green IO London 2026 takes place 30 September – 1 October 2026 at Convene Sancroft, St Paul’s — part of the FOST federation and the autumn anchor of Green IO’s 2026 calendar, following editions in Singapore, New York, Amsterdam, and Munich.

London has become one of Green IO’s strongest communities. Past attendees — from DEFRA, Cambridge University Press, NHS England, and Goldman Sachs — consistently describe the format as unusually engaged: short talks, a single stage, and minimal corporate pitch content. The 2026 edition continues that tradition.

What makes London different

The UK digital sustainability scene has matured quickly. Government departments are publishing emissions methodologies for digital services. Enterprise teams are delivering measurable GreenOps wins — cost reduction and carbon reduction together. Green IO London is where those stories get shared without polish.

The conference premise is straightforward: the digital sector emits greenhouse gases comparable to global road freight. IT can support the low-carbon transition — but only if the sector cleans its own house first.

What to expect in 2026

While the full 2026 agenda will be published closer to the event, Green IO London’s programme typically combines:

Workshop day — engineer-to-engineer deep dives on cloud and AI sustainability, LCA data at scale (Resilio DB), GreenOps tooling, and organisational culture change beyond footprint numbers.

Conference day — keynotes and talks spanning:

• Sustainable CI/CD — shifting compute to lower-carbon regions in real time
• Enterprise GreenOps — UK and global case studies on cloud optimisation delivering business value
• Public-sector digital sustainability — DEFRA, DWP, GOV.UK One Login, and NHS resilience under climate stress
• Heat reuse from datacenters — practical barriers and recent collaborations
• Software Carbon Intensity (ISO 21031) applied to the web
• carbon.txt and transparency — discoverable sustainability data across tech companies
• AI and network capacity — a 2030 discussion on whether infrastructure can keep pace

Past editions featured Anne Currie (Building Green Software), Lydia Tabbron (DEFRA), Jennifer Marks (GOV.UK One Login), and Ben Tongue (NHS England) — a signal of the practitioner depth London attracts.

Building bridges — in Green IO’s DNA

Green IO founder Gaël Duez describes the blossoming of green IT tools as a heart-warming signal — but stresses that sharing experience is now pivotal. London embodies that: practitioners who have found their community, returning year after year with lessons they apply directly to their projects.

Whether you work in public digital services, enterprise cloud, or green software engineering, London is designed as a place to decarbonise your stack with people who have done the work.

Green IO 2026 — other editions

Also see our coverage of Green IO Paris 2025 for context on how the European edition has evolved.

At a glance

Green IO London 2026 is part of the Future Of Software Technologies conference federation. Call for speakers is open for anyone with experience reducing the environmental footprint of technology.