Sustainable Information Technology

What is Green IT?

‘Green IT’ is a relatively new concept. I want to give a simple explanation of what Green IT is, but that turns out to be surprisingly tricky. By the end of this article we will have a reasonable working definition, but we have to recognise that the concept of Green IT is developing over time.

Green IT refers to two things which are in themselves changing rapidly. The first is our understanding of what is Green and what isn’t. The second is Information Technology, which is extending its scope, techniques and social and geographical presence on a daily basis.

Why define Green IT?

What is Green IT? This book helps answer the question

What is Green IT? This book helps answer the question


Why is it important to define Green IT so closely?

As we’ll see, current influential definitions are surprisingly wide apart in their accounts of what Green IT is. For example, if an individual or an organisation wants to reduce IT related carbon emissions and they are following the BCS definition, they will focus on different actions to someone who is following the Greenpeace understanding of Green IT.

So here is our first definition, courtesy of “Green IT for Sustainable Business Practice” by Mark G. O’Neill and published by BCS:


Green IT is a collection of strategic and tactical initiatives that directly reduces the carbon footprint of an organisation’s computing operation… However, Green IT is not just focused on reducing the impact of the ICT industry. It is also focused on using the services of ICT to help reduce the organisation’s overall carbon footprint.

There are some interesting things to note about this basic definition.

The first is that it’s all about organisations, not individuals. We have to question this, given the tide of information technologies currently sweeping the world in the form of mobile computing devices.

The second is that the ‘strategic and tactical initiatives’ have a different emphasis to what Greenpeace, for example, would see as the most important Green IT strategies. More on that soon.

Next, there is an emphasis on how ICT can itself be used to help to lower carbon emissions in other areas. For example, IT connectivity can cause people to travel less because they meet, make purchases, or carry out banking transactions via their computers.

Direct energy consumption vs. embodied emissions

Finally, although it isn’t apparent from the qoute above, the BCS / O’Neill view of Green IT emphasises the ICT life cycle as follows:

…it is crucial that we understand not only the environmental impact of the energy consumption of infrastructure, but also the environmental impact of its manufacture, transport, usage and disposal. It is therefore vital that we consider not only the GHG emissions associated with energy consumption, but also the embodied emissions.

Green IT ‘strategic and tactical initiatives’

So what are the Green IT activities we should be focusing on, according to BCS / O’Neill? They can be summarised as follows:

  • Change the structure and culture of organisations so that Green IT is high on the corporate agenda and aligned with Corporate Social Responsibility policies
  • Make sure individuals and teams are in place to carry out structured Green IT activities
  • Embed Green IT practices into IT processes (based on the ITIL framework)
  • When procuring IT infrastructure, adhere to standards (such as Energy Star and EPEAT) which emphasise both lower embodied emissions and lower power consumption
  • Manage data centre power efficiency, with an emphasis on PUE (Power Utilisation Efficiency)
  • Move towards virtualisation, cloud computing and software as a service
  • Encourage common-sense actions and tactics such as switching off computers, and duplex printing

The Greenpeace definition of Green IT

According to its April 2012 report “How Clean is Your Cloud?”,  Greenpeace has a straightforward definition of Green IT:

Green IT=
Energy Efficiency+
Renewable Energy

The Greenpeace view is that data centres, with their massive consumption of power, should be the main focus of Green IT initiatives.

…the source of electricity must be factored into a meaningful definition of “green IT”. Energy efficiency alone will, at best, slow the growth of the sector’s footprint… renewable energy needs to become the priority for IT companies as they rapidly expand their data center infrastructure.

Current measures such as PUE are misleading, they argue, because they do not question the source of electricity itself. There are other fundamental reasons why Greenpeace sees PUE ratings, which some companies use as a way to indicate how ‘green’ they are, as poor indicators of environmental performance. The drift of the argument is that IT companies need to use better metrics, and that some of these are already available.

Greenpeace ‘strategies and tactics’ for Green IT

Greenpeaces’s “pathway to a cleaner cloud” includes these key features:

  • Tapping renewable grid power
  • Power purchase agreements for renewable energy
  • Onsite renewable energy
  • Investment in renewable energy or offsetting local energy demand
  • Funding negawatts: local energy efficiency offsets
  • Clean energy advocacy by companies

So, what is Green IT?

Let’s put these approaches together.

Like the BCS / O’Neill version of Green IT, the Greenpeace report is focused on companies and for the most part leaves out individual users of IT. Of course the Greenpeace report is all about corporate cloud computing infrastructure, and the BCS publication is aimed at obtaining a Green IT professional qualification for use in the commercial world, so you wouldn’t expect them to be focusing on anything else.

Both approaches, I’m sure, recognise the need for the engagement of individuals in Green IT, but that isn’t an emphasis of either of these publications.

Bearing that in mind, here’s my working definition of Green IT:

Green IT is a set of practical measures designed to ensure that Information Technology is developed, delivered and used in a way that is environmentally friendly, sustainable and energy efficient.

These practical measures include:

For organisations and individuals:

  • Procure IT equipment and other infrastructure products based on both their power consumption efficiency and their embedded emissions. Use standards such as EPEAT and ENERGY STAR to help with buying decisions
  • Prolong the life of IT equipment, or when appropriate move to lower energy consumption products
  • Move to duplex printing as the default
  • Move to cloud computing and software as a service where appropriate
  • Turn off unused equipment
  • Recycle IT consumables

For organisations only

  • Put Green IT high on the agenda, with board representation
  • Structure the organisation to support Green IT initiatives
  • Change IT processes (such as Service Asset and Configuration Management) at the micro level to embed Green IT
  • Manage data centre power efficiency. Review metrics to ensure that they help to manage energy consumption reductions effectively
  • Move to server virtualisation, cloud computing and software as a service where appropriate
  • Implement server (and PC) power management
  • Use renewable and cleaner power sources

Have I missed anything? Let me know!