Nature operates on the principles of zero waste. Trees make flowers and fruit for germinate and grow. Excess of flowers and fruits are consumed by other species. They fall on ground, decompose, feed various organisms and microorganisms and enrich the soil. all other species, except plant, exhale carbon dioxide, which plants takes in and use for their own growth and releases oxygen for our survival. Nitrogen from the waste is transformed into protein by microorganisms, animals and plants. The Earth's major nutrients - carbon, hydrogen, oxygen, nitrogen - are cycled and recycled. This cyclic flow of materials, from cradle - to - cradle, has nourished our planet for millions of years. This material flow can be termed as Biological cycle. Then came industries, which altered the natural equilibrium of materials on the planet. we took substance from the Earth's crust and concentrated, altered and synthesized them into vast quantities of materials that cannot safely be returned to soil and its original biological cycle. This material flow is termed as Industrial cycle.
The rapidly growing world energy use has already raised concerns over supply difficulties, exhaustion of energy resources and heavy environmental impacts (ozone layer depletion, global warming, climate change, etc.). The global contribution from buildings towards energy consumption , both residential and commercial, has steadily increased reaching figures between 20% to 40% in developed countries, and has exceeded the other major sectors: industrial and transportation.
The Green concept is to consume appropriate energies and resources of any forms that effect the environment and its various components, and to make use of resources efficiently and sufficiently for present and future growth of an entire system.
Several terms are left open ended here, as to understand the wider concept of being GREEN
Appropriate – Quantity can be minimum or maximum in present state, in order to conserve for the future.
Effect – it can be defined as useful or harmful in different condition and situation.
Environment and its components – it is necessary to consider every form of element, whether living or non-living.
Efficiently and sufficiently – whether to get maximum output at one go and continue giving more input for efficiency or understand the minimum requirement for the present needs and reserve for future and remain sufficient.