A fundamental requirement that any energy supply system must satisfy for economic viability is a sufficiently high energy return on energy investment (EROI) for manufacturing, installing, operating and maintaining the system over its operating life. The question of what constitutes a sufficient return depends on the nature of the economy and society that the energy supply system is intended to support—while an EROI <1 implies a net energy sink, an EROI >1 does not automatically entail viability. Consider the limiting case in which net energy supply is zero, i.e. EROI =1. This would entail an economy consisting entirely of an energy supply sector that supported itself, but allowed for no economic activity beyond this. It’s certainly possible to imagine a functional economy along such lines, but it implies that every person living in such a society must dedicate their life to and focus all of their attention and effort on providing for the subsistence energy needs of their economic system. Such an economic system would serve no purpose beyond its own perpetuation; citizens of such a society might very well consider their lives to constitute a form of slavery to their economy. Continue reading
Comprehensive understanding of the environmental and resource implications for humanity’s economic activity involves thinking in terms of the full life cycles of our goods and services. Thanks in large part to the work of William McDonough and Michael Braungart, awareness of “cradle to cradle” design thinking has spread beyond the worlds of industrial ecology and ecological economics to establish a toehold in popular sustainability-oriented discourse. Over the past decade or so, it has started to dawn on an increasing number of us that the things we consume on a daily basis are connected to a globe-spanning network of socio-ecological consequences the extent of which is belied by the apparently modest materiality of our “stuff”. It’s in the context of this awakening systemic insight that the concept of embodied energy has—at least amongst those of us with an interest in the relationships between the spheres of technology, society and environment—come to be meaningful. Here in Australia, particular effort has been directed towards making information about the embodied energy of housing construction materials widely available—and moreover, to making this understandable for people involved in making the decisions that this might inform.