Energy in History - The Basic Environmental History - page 6

Here is a synthetic view of the sources characterizing these two main epochs:

First epoch Second epoch

Food Coal

Firewood Oil

Fodder (for working animals) Primary electricity

Water power Natural gas

Wind power Nuclear power

Although the energy system prevailing today is apparently different from the
simple digestion of food (the rewood

by our primitive ancestors, it is based on the same principle, which is the oxidation
of Carbon compounds by breaking their chemical ties. Since Carbon compounds
are de

rst energy source), or from the burning of

ned in chemistry as organic compounds and organic chemistry is the
chemistry of organic compounds, we could de ne all the energy systems which

have existed until today as organic and the economies based on those organic
sources as organic economies. Coal, oil and natural gas, the basic sources oxidized
today in order to bring about organized, that is mechanical, work, heating or light
are carbon compounds such as bread or

rewood. The difference between pre-
modern and modern energy systems depends on the fact that, until the recent energy
transition, organic vegetable sources were exploited, whilst from then on organic
fossil energy sources became the basis of our economy. Since organic vegetable
sources of energy were transformed into work by biological converters (animals)
and fossil sources are transformed by mechanical converters (machines), we are
able to distinguish past economies according to the system of energy they employed
and the prevailing kind of converters in:

1. organic vegetable economies or biological economies;
2. organic fossil economies or mechanical economies. 6

Given the importance of energy in human history, changes in the use of this
main input mark the evolution of humans in relation to their environment much
more than changes in the use of those materials, such as stone and metals, ordinarily
utilized by the historians to distinguish the main epochs of human history.

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refers to Carbon compounds. The term has been used by F. Cottrell and
A. Wrigley (see the previous footnote) to distinguish past agricultural economies (whose base was
an organic energy system) from modern economies (based on mineral fossil sources). However,
fossil fuels are also organic compounds. To avoid misunderstandings I think it useful to distinguish
“ Past agricultural organic vegetable economies ” from “ Modern organic fossil economies ” .

In chemistry “ organic ”