Energy quality

This eventually became an issue endemic to the entire region, reducing the overall profitability of older mills as newer ones were built.

Similarly, the quality of energy from electricity offers immense advantages over steam, but did not become economic or practical until the 20th century.

A similar scenario plays out in nature and biology, where living organisms can extract energy of varying quality from nature, ultimately driven by solar energy as the primary driver of thermodynamic disequilibrium on Earth.

This is effectively because disciplines such as economics failed to recognize the thermodynamic inputs into the economy (now recognized as thermoeconomics), while disciplines such as physics and engineering were unable to address either the economic impacts of human activity, or the impacts of thermodynamic flows in biological ecosystems.

Thus, the broad-stroke, global system-in-the-large discussions were taken up by those best trained for the nebulous, non-specific reasoning that such complex systems require.

90–91) the ranking and scientific analysis of energy quality was first proposed in 1851 by William Thomson under the concept of "availability".

Exergy analysis now forms a common part of many industrial and ecological energy analyses.

Cengel (2001, p. 132) state that energy forms of different qualities are now commonly dealt with in steam power engineering industry.

However energy engineers were aware that the notion of heat quality involved the notion of value – for example A. Thumann wrote, "The essential quality of heat is not the amount but rather its 'value'" (1984, p. 113) – which brings into play the question of teleology and wider, or ecological-scale goal functions.

For example, A. Grubler [1] used two types of indicators of energetic quality pars pro toto: the hydrogen/carbon (H/C) ratio, and its inverse, the carbon intensity of energy.

From this view, in contrast with that outlined by Ohta, energy quality is upgraded in the multistage trophic conversions of ecological systems.

Culp's treatment made use of a subscript to indicate which energy form is being talked about.

Both the direct and indirect energy inputs embodied in goods and services must be included in the denominator."

This is to say that the evaluation of "relative ease" of an energy conversion is only partly dependent on transformation efficiency.

As Ohta wrote, "the turbine generator and the electric motor have nearly the same efficiency, therefore we cannot say which has the higher quality" (1994, p. 90).

Like Ohta, H.T.Odum also sought to order energy form conversions according to their quality, however his hierarchical scale for ranking was based on extending ecological system food chain concepts to thermodynamics rather than simply relative ease of transformation .