Emergy Energy and Quality

Emergy, defined as the energy of one form (usually solar energy) required through all processes and transformations to make a product or flow, provides a numeric framework for comparison of different forms of energy and materials, providing a measure ofquality in directly comparable units (solar emjoules, or sej). Emergy is often referred to as energy memory, reflecting that this system synthesis approach is effectively a form of accounting that traces energy flow and dissipation back through all necessary transformations to scale all flows relative to a common energy benchmark (solar equivalent energy). Emergy synthesis allows comparison of energy flows of different form (the term 'emergy synthesis' instead of 'emergy analysis' is used since synthesis is the act of combining elements into coherent wholes while analysis dissects and breaks apart systems to build understanding from the pieces upward; emergy synthesis strives for understanding by grasping the wholeness of systems). Different forms of energy have different qualities that arise from the energy required to make them. In self-organizing adaptive systems, it is argued, forms of energy that require larger investment per unit available energy must provide commensurate higher-quality cybernetic work in the form of feedback control. Transformity is an index of quality and quantifies the emergy invested per unit available energy produced (i.e., emergy per exergy, sej J-1) for each flow in a system of interest. In like manner, specific emergy is an index of quality of material by quantifying the emergy investment per unit mass produced (sej g-1).

The use and transformation of material and energy is system dependent, where the appropriateness of energy in a particular system is dictated by its form and is related to its concentration. The processes of the biosphere are infinitely varied and are more than just thermodynamic heat engines. As a result, the use of heat measures of energy that can only recognize one aspect of energy, its ability to raise the temperature of things, cannot adequately quantify the work potential of energies used in more complex processes that span multiple levels of system processes, ranging from the smallest scale to the largest scales of the biosphere.

Degraded energy

Emout = ^EnTrn Trout = Emout/Eout where

Degraded energy

Emout = ^EnTrn Trout = Emout/Eout where

E1 n = available energy inputs

Eout = available energy of output Em = emergy Tr = transformity

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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