Energy
In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The SI unit of energy is the joule, which is the energy transferred to an object by the work of moving it a distance of 1 metre against a force of 1 newton.
Renewable Energy
Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy often provides energy in four important areas: electricity generation, air and water heating/cooling, transportation, and rural (off-grid) energy services.
Sustainability
Sustainability (from 'sustain' and 'ability') is the process of change, in which the exploitation of resources, the direction of investments, the orientation of technological development and institutional change are all in harmony and enhance both current and future potential to meet human needs and aspirations. The organizing principle for sustainability is sustainable development, which includes the following interconnected domains: environment, economic and social. Sub-domains of sustainable development have been considered also: cultural, technological and political. Sustainable development, is the development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Brundtland Report for the World Commission on Environment and Development (1992) introduced the term of sustainable development.
Sustainability
Two types of choices seem to me to have been crucial in tipping their outcomes towards success or failure: long-term planning, and willingness to reconsider core values. On reflection, we can also recognize the crucial role of these same two choices for the outcomes of our individual lives.
Jared Diamond, Collapse: How Societies Choose to Fail or Succeed (2005): "On the fates of past societies facing problems of sustainability," p. 522
Energy
It is important to realize that in physics today, we have no knowledge of what energy is. We do not have a picture that energy comes in little blobs of a definite amount.
Richard Feynman, in The Feynman Lectures on Physics (1964) Volume I, 4-1
Sustainability
Our deep urge to evolve to a more spiritually mature level of understanding and living, and to create a social order that promotes more justice, peace, freedom, health, sanity, prosperity, sustainability, and happiness, absolutely requires us to stop viewing animals as food objects to be consumed and to shift to a plant-based way of eating.
Will Tuttle, The World Peace Diet (2005). Ch. 2