Green computing or Green IT, refers to environmentally sustainable computing or IT. It is “the study and practice of designing, manufacturing, using, and disposing of computers, servers, and associated subsystems—such as monitors, printers, storage devices, and networking and communications systems—efficiently and effectively with minimal or no impact on the environment. Green IT also strives to achieve economic viability and improved system performance and use, while abiding by our social and ethical responsibilities. Thus, green IT includes the dimensions of environmental sustainability, the economics of energy efficiency, and the total cost of ownership, which includes the cost of disposal and recycling. It is the study and practice of using computing resources efficiently.”

With increasing recognition that man-made greenhouse gas emissions are a major contributing factor to global warming, enterprises, governments, and society at large now have an important new agenda: tackling environmental issues and adopting environmentally sound practices. Greening our IT products, applications, services, and practices is both an economic and an environmental imperative, as well as our social responsibility. Therefore, a growing number of IT vendors and users are moving toward green IT and thereby assisting in building a green society and economy.

Green computing researchers look at key issues and topics related to energy efficiency in computing and promoting environmentally friendly computer technologies and systems include energy efficient use of computers, design of algorithms and systems for environmentally-friendly computer technologies, and wide range of related topics.

To comprehensively and effectively address the environmental impacts of computing/IT, we must adopt a holistic approach and make the entire IT lifecycle greener by addressing environmental sustainability along the following four complementary paths:

  • Green use — reducing the energy consumption of computers and other information systems as well as using them in an environmentally sound manner.
  • Green disposal — refurbishing and reusing old computers and properly recycling unwanted computers and other electronic equipment.
  • Green design — designing energy-efficient and environmentally sound components, computers, servers, cooling equipment, and data centers.
  • Green manufacturing — manufacturing electronic components, computers, and other associated subsystems with minimal impact on the environment.

These four paths span a number of focus areas and activities, including:

  • Design for environmental sustainability
  • Energy-efficient computing
  • Power management
  • Data center design, layout, and location
  • Server virtualization
  • Responsible disposal and recycling
  • Regulatory compliance
  • Green metrics, assessment tools, and methodology
  • Environment-related risk mitigation
  • Use of renewable energy sources and
  • Eco-labeling of IT products

Modern IT systems rely upon a complicated mix of people, networks and hardware; as such, a green computing initiative must be systemic in nature, and address increasingly sophisticated problems. Elements of such a solution may comprise items such as end user satisfaction, management restructuring, regulatory compliance, disposal of electronic waste, telecommuting, virtualization of server resources, energy use, thin client solutions, and return on investment (ROI).