Sustainability occurs when human activity does not adversely affect the quality of the environment and resource base available for future generations of living things on the planet. Sustainability is the balance and complement between a developed economy and the natural environment. Sustainable growth means that a future state of human well being and societal development is attained without destroying the natural resources that provide the bases for current and future prosperity. Necessary elements of the desired future state are economic development and prosperity, growth with minimum negative impacts on ecosystems, improved human health, reduced resource extraction, and greater equity in the distribution of resources and services for human development. The term sustainability is used very loosely as the way to maintain steady economic development while keeping the desirable level of the environment and the acceptable level of GHG emission.
Human activities influence natural processes on and in the Earth.
Sustainability is achieved when these processes overall are not changed by human interference. The key aspects of a global sustainable future are the internalization of externalities as well as altered or broadened decision making criteria for investments. Sustainability involves multiattribute aspects of issues. In terms of energy, it is the overall performance of the energy system which leads to natural source consumption and emission. As such, we need to understand impacts in order to understand sustainability.