ABSTRACT
There are some points of detail: a) As in all energy costing schemes, enthalpy and heat input data must be firmly based on the primary fuel requirement (or what Slesser has termed the Energy Network Input)—so that 1 Kw hour at user must be costed into the system as the equivalent of approximately 3.3 Kw hours of fossil fuel, using current national grid average fuel requirements. (Substitution of more nuclear, hydro or ‘wave power’ inputs to the grid would, of course, alter the E.N.I, value, although charges will be slow, and possibly small, in view of the very large capital energy charges implied by the newer coal/oil substituting technologies). In any event, electricity will carry a very high index weighting relative to many other energy media. b) Implicitly, such an index based on ‘real world’ heat and work values embraces not only the losses of “practical system” (due to friction, inefficient lagging and heat exchange), but also those qualities of energy made inaccessible by the HIGH RATE OF WORKING. (We must recall that the ‘ideal’ Carnot engine only approaches its maximum efficiency, given by
WHEN OPERATING “NEAR EQUILIBRIUM”—or very slowly”!). It would scarcely seem appropriate for a practicable management energy accounting system to lean upon the complexities of non-equilibrium thermodynamics, but it is nonetheless a commonly noted experience of practical systems that higher rates of working, while achieving more ‘product’, do so at the expense of large proportions of primary fuel input. (See for example “Green M” on the energy intensive nature of modern agriculture versus primitive slow agriculture and NASA Handbook by Bio Astronautics on the efficiency of human athletes at different work rates).
