Green IT is a set of operational practices that reduce the energy use and carbon emissions of IT infrastructure — servers, data centres, end-user devices — without giving up the performance a business needs. Unlike one-off investments (swapping in efficient hardware, say), Green IT practices are everyday decisions an IT team makes, which accumulate into a measurable effect over time.
Quick Overview
What you’ll learn:
- How to measure the carbon footprint of IT infrastructure as a starting point
- A table of operational practices that cut energy use
- A first-steps plan for rolling out Green IT in an organisation
- How Green IT connects to ESG reporting and the CSRD directive
Who this article is for:
- IT managers looking for ways to cut infrastructure energy costs
- ESG specialists responsible for reporting an organisation’s carbon footprint
- Systems architects designing infrastructure with energy efficiency in mind
Reading time: 6 minutes
How to Measure the Carbon Footprint of IT Infrastructure
Before a team starts rolling out Green IT practices, it needs a reference point — without a baseline measurement, it’s hard to show that changes actually cut energy use. The core data-centre metric is PUE (Power Usage Effectiveness) — the ratio of a data centre’s total energy consumption to the energy consumed directly by computing equipment. A value close to 1.0 signals high efficiency; higher values point to energy lost to cooling and supporting infrastructure.
In its recurring data-centre research, the Uptime Institute tracks global trends in energy efficiency and consistently identifies cooling as one of the largest — and, at the same time, one of the easiest to optimise — components of energy use outside computing itself.
Green IT Operational Practices That Cut Energy Use
| Area | Practice | Effect |
|---|---|---|
| Servers | Consolidating and virtualising underutilised servers | Less physical hardware drawing power at idle |
| Cooling | Raising the target server-room temperature within safe limits | Lower energy use by climate-control systems |
| Code and architecture | Optimising queries and processes that draw excess compute | Lower energy use for the same business outcome |
| End-user devices | An automatic sleep policy for hardware outside working hours | Reduced energy draw from idle devices |
| Cloud | Choosing a cloud provider region powered by renewable energy | A lower carbon footprint for the same workload |
A First-Steps Plan for Rolling Out Green IT
- Measure current energy use and calculate PUE if you run your own server room — without that reference point, it’s hard to assess progress.
- Identify underutilised or outdated resources — servers running at low utilisation are the easiest consolidation target.
- Introduce an automatic power-management policy for end-user devices — putting hardware to sleep outside working hours is a low-cost change with a measurable effect.
- Review your choice of cloud regions and providers against energy sources — some providers publish data on renewable-energy share by region.
- Measure the effect after rolling out changes and document it — that data feeds both further optimisation and ESG reporting.
Green IT as Part of ESG and CSRD Reporting
The CSRD (Corporate Sustainability Reporting Directive) requires a growing group of companies to report environmental data, including the carbon footprint from operational activity — IT infrastructure is part of that footprint, though it’s often overlooked in early reporting cycles. Organisations that already measure and optimise IT energy use for cost reasons have a real advantage when rolling out mandatory ESG reporting — the data the sustainability team needs is already being collected by IT for a completely different reason entirely.
It’s also worth remembering that Green IT practices aren’t a one-off project but an ongoing part of operations — new infrastructure added without energy efficiency in mind gradually erodes earlier savings, unless the topic gets built into a team’s standard purchasing and design processes.
Read Also
- GreenOps and Sustainable IT - ESG Training for Tech Teams — a deeper look at sustainable IT practices through an ESG lens
- GreenOps: Sustainable Practices for IT Teams — how to weave Green IT practices into a team’s everyday way of working
Build Your Skills
This topic connects to the CSRD & ESG Reporting With IT Tools and CSRD: A Practical Sustainability Reporting Workshop courses. Check the program and sign up to build your skills with EITT’s experts.
Frequently Asked Questions (FAQ)
What is PUE and why does it matter for Green IT?
PUE (Power Usage Effectiveness) is the ratio of a data centre’s total energy consumption to the energy consumed directly by computing equipment. A value close to 1.0 signals high efficiency — the higher the value, the more energy is lost to cooling and supporting infrastructure instead of computing itself.
What’s the simplest Green IT practice to roll out first?
Automatically putting end-user devices to sleep outside working hours — a low-cost policy change that requires no new hardware investment yet delivers a measurable cut in energy use from idle equipment.
How does Green IT connect to the CSRD directive?
CSRD requires reporting environmental data, including the carbon footprint from operational activity — IT infrastructure is part of that footprint. Organisations that already measure IT energy use for cost reasons have data ready to feed into mandatory ESG reporting.
Does consolidating servers always cut energy use?
Usually, yes, if the servers being consolidated were underutilised — less physical hardware sitting idle means less energy consumed regardless of actual compute load. The effect depends, though, on how underutilised the infrastructure was to begin with.