**1. Introduction**

Today, software is extensively used by all of us for commercial and noncommercial purposes and it is controlled by various entities. The total energy consumption by ICT is between 5 and 9% and is going to increase annually by 6–9%. (**Figure 1**) [23]. In India, the exiting ICT facilities have the energy performance index ranging between 230 and 310 kWh/m2 /year. The greenhouse gas emissions by ICT is estimated to be 2.8% in total global emissions, but as usage of ICT can also reduce the emission rate by 15%. This calculation is on consumers who use ICT devices. But energy consumption levels can be further reduced from the current levels if we apply green software development lifecycle. The existing Software Development Life Cycle process framework is not adequate when concerned with energy consumption. This is mainly due to the lack of awareness in the Green Based Software Development life cycle process. The existing Green based software development model namely Green Reference Model is focuses on the three phases of the process called development, usage, and end of life. But the GREENSOFT model does not provide Green-based approach in entire Software Development Life Cycle phases which is a major setback of GREENSOFT model.

The existing model for Green software engineering does not consider the Requirement, Design, Coding, Testing and Implementation phases of SDLC. In order to achieve green software engineering the entire software development process is to become Green.

**Figure 1.** *ICT electricity consumption.*

## **2. Environmental informatics**

Sustainability has become a very essential factor to consider doing business in recent times. If that business has fails to maintain sustainable development it receives significant public criticism and they may lose the market [1].

The usage of computing power is to develop the more sustainable world [2]. The answer for the ecological crisis can be solved by knowledge acquisition. The development of feedback information should be concerned with model makers and system analysts. Environmental Informatics (EI) [2] is the combination of information systems of problem-oriented knowledge from the fields of management and environmental science and computer science. EI is emerged for the requirement of domain-specificity. The computer scientists have the challenge of designing the information processing system for using the environmental data.

The Computational Sustainability (CompSust) [2] is closely associated with the Institute for Computational Sustainability (ICS) with funding starting from 2008 by the U.S. National Science Foundation. CompSust is developed by ICS as "inter disciplinary field to balance the needs (environment, economical and societal) of sustainable development using computer and information science, operations research, applied mathematics, and statistics. The Brundtland definition for CompSust community refers to address the need of basic human." "Balancing" might address the issue to some extend with no reference of deeply normative issues which are connected to distributive justice. Thus, an algorithm can resolve normative issues, which is yet to be developed for greening ICT.

Greening ICT in industry application can run in design phase, classification of ICT systems development phase, execution of software systems phase and complex installation phase and in software development of the Life cycle of ICT systems [3] there are a lot of changes to save energy. The energy can be saved efficiently by using computing resources and avoiding recurring work such as recompiling. Based on World Commission on Environment and Development (WCED) [2], "sustainable development" could be defined as sustainable system use of a system to fulfill its function (F) for a time (L).
