ISO 14001 originated in the 1990s, and ISO 50001 is even newer. The basic and easily understandable concepts behind them have, however, been around for more than 100 years.
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Harrington Emerson’s paper, “Efficiency as a Basis for Operation and Wages” (The Engineering Magazine, 1909) uses examples from nature to illustrate the gap between existing and achievable uses of natural resources, and it also introduces very explicitly the science of lean manufacturing. On page 14 of the paper, Emerson compares the relative inefficiency of combustion engines to very efficient biochemical processes: “An oil engine may reach 30 per cent thermal efficiency, but the salmon, assuming his whole weight to be pure oil, without consuming it, uses up several times more energy than is yielded by an equal weight of oil in combustion.”
The salmon uses atomic, not thermal, energy.
“Atomic” refers to biochemical rather than nuclear power, but the implications are nonetheless obvious. The Carnot cycle underscores the built-in inefficiency of thermodynamic processes that extract mechanical energy through the transfer of heat from a hot reservoir (like a furnace) to a cold reservoir. The Carnot cycle is actually a theoretical best case, and real-world power cycles like the Otto and Diesel cycles are even less efficient.
We all know, in contrast, how much exercise it takes to get rid of one pound of body fat. The human body, like that of the salmon, uses energy very efficiently. This suggests the generation of power from chemistry rather than combustion, and the modern fuel cell circumvents the efficiency limits of traditional power-generation cycles by converting chemical energy directly into electricity.
Emerson next addresses the issue of lighting: “The fire-fly, the glow-worm, the phosphorescent jelly-fish, show a far higher light efficiency than has ever been reached even by vacuum lamps.” To this Emerson adds, on page 17: “The fire-fly converts the hydrocarbons of its food into light with an efficiency of 40 per cent. It flashes its light at intervals, thus making it most effective by contrast with the surrounding darkness, and it emits no more light than is necessary for its purpose.
“In production the fire-fly is about seven hundred and fifty times as efficient, in volume use ten times as economical, in time use twice as economical. The fire-fly is fifteen thousand times as efficient as his human rival.”
Incandescent lamps are very inefficient because they convert most of their electrical energy into heat rather than light. This is not necessarily a loss during winter, but it is an added cost during summer when it works against air conditioning. The fluorescent light, and now the light-emitting diode, seek to approach the efficiency of bioluminescence through the direct conversion of electricity into light.
The lesson of both these examples makes it clear that nature shows it is possible to do better, and the challenge to the engineer is to figure out how to do it. Emerson continues with the reference on page 14: “To attain the high efficiency of the atomic energy of the fish, the high mechanical efficiency of the bird, the high lighting efficiency of the fire-fly, is not an ethical or financial or social problem, but an engineering problem; and to the engineering profession, rather than to any other, must we look for salvation from our distinctly human ills, so grievously and pathetically great.”
To this Emerson adds, on page 18, the need to assess entire supply chains for inefficiencies: “If any human activity is followed out from initial reservoirs to final attainments, a similar sequence of losses will be found, losses gauged not by any ideal or unattainable standard, but by what is being continuously accomplished all around us. Even if, as yet, some of the high efficiencies seen in Nature are beyond reach, it is a greater reason for eliminating those wastes which are avoidable and which are primarily responsible for the starvation of men, women and children.”
The paper continues by addressing the kind of motion inefficiency that was similarly identified by Henry Ford, Frederick Winslow Taylor, and Frank Gilbreth. The first chapter of “Efficiency as a Basis for Operation and Wages” is definitely worth reading for the purpose of assimilating the thought process. The paper is available on Google books here.
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