As I stoke the boilers here at Beyond this Brief Anomaly after another (much) longer-than-anticipated intermission, it’s worth checking in on what this project has been all about to date. In a nutshell: I’ve attempted to make some modest in-roads into improving how we make sense of energy-related concepts, given the central role that I see for these in coordinating social action as we seek ways of living well together in the face of the increasingly urgent socio-ecological dilemmas confronting humanity. And in doing this, I’m drawing on principles from the field of inquiry known as systems thinking, or simply systems. If I were to try capturing what this means in essence, it would be along the lines of “considering the situations in which we’re interested as comprehensively as we’re able, by paying attention to their encompassing contexts.” The approach I’m taking extends this question of context to include considerations around cognition, language and meaning. Put simply, this implies treating the energy-related concepts that the inquiry deals with as sense-making “tools” and “artefacts” constructed by us. As such, they constitute important and influential parts of our shared culture. With them and through them, we bring our circumstances into being. What this implies is that the quality and coherence of our conceptual spaces “in here” affects the nature of our physical, social, economic, political etc. conditions “out there”. Attending to this “interior dimension” can have profound implications for the quality of the worlds that we bring about through the actions we engage in together. Continue reading
The last post looked at what I’ve called the engineering view of systemic efficiency, specifically the concept of available energy, or exergy. I refer to this as systemic because it considers energy conversion processes in relation to their specific operating contexts, in order to understand the useful work that a system can provide. While energy conversion processes serve an infinite array of human purposes, in the proximate or most immediate sense, we carry out energy conversions in order to do work—to effect transformations in our material worlds—and to provide heating (and while technically it’s not necessary to further differentiate it here, to provide illumination also). The systemic view provided by exergy analysis deals directly with the question of how much utility we can derive from an energy conversion process, and so it allows us to think about energy resources and infrastructure in a more concrete way than when we conduct analysis in terms of the nominal heating value of primary sources or fuels, in isolation from the particular situations in which they are used. Differences in energy use situations—different conversion technologies, implemented in different ways, operating in different physical environments—lead to differences in the utility that can be derived from an energy source. In establishing the efficiency of an energy conversion process—the useful energy output from the process divided by the nominal energy input—a focus on conversion systems and their parts (including the particular energy sources involved) only gets us so far. For a comprehensive view of efficiency we need to consider energy conversion processes in terms of all three levels of the basic systems hierarchy of system, sub-systems and supra-system. Exergy analysis provides the means for achieving this.
My reason for identifying this approach to thinking about efficiency as the engineering view relates in part to the scale at which exergy analysis’s systemic approach is most fruitfully applied—namely the plant or equipment scale. In other words, this is most immediately useful at the micro-economic or enterprise level, where we deal with technology components that make up economic units. In macro-economic terms, exergy analysis does have particular value for understanding performance of an economy’s energy sector, and also provides especially valuable insights in relation to transport and manufacturing activities. Coming to terms, though, with industrial societies—or, as we’ll see, any forms of social organisation for that matter—in physical- or energy-economic terms requires that we look beyond the enterprise and even sectorial levels. That is, we need a basis for thinking holistically about societies and their economic forms that relates energy supply and use at the overall macro-scale. It’s for this purpose that the concept of energy return on investment (EROI) (or energy return on energy investment—EROEI), has started, only relatively recently, to be better appreciated as so important. EROI tells us about the energy available for economic activity other than the supply of energy itself, and it is in this sense that I referred to it in the introductory post on efficiency as, roughly speaking, the economic equivalent of thermodynamic availability. Continue reading
So far in looking at the broad topic of efficiency, we’ve focused on what I described in the introductory post as the analytic perspective. In this post I’ll start to consider the systemic view of efficiency in more detail, by taking a closer look at the concept of available energy: the maximum work output achievable when a system is brought into equilibrium with its environment (or, as the corollary of this, the minimum work input required to bring about a given change in a system’s state). Continue reading
The perennial human interest in keeping a check on the costs of doing what we do is hardly surprising. In fact, the significance of this as an organising principle extends well beyond our own species: it plays an important role in the processes of biological evolution, where the viability of any organism depends on maintaining a sufficient degree of what we might call “energetic leeway” to weather the range of environmental variation encountered. In the human realm, it manifests in a perhaps more mundane way in the disinclination that people tend to have for working harder than necessary to do what they want to do—if there’s an easier way of satisfying our needs and desires, we tend on the whole to be good at finding it. Continue reading
In the last post I set out a rough framework for organising various aspects of energy efficiency that impact on the energy costs of the energy that we use. Accessing any energy source requires the use of energy; and only a portion of the overall energy that we use goes directly to the specific service that we desire, such as moving goods or people from one place to another. In some situations—for example, many heating applications—almost all of the supplied energy is converted to directly useful forms, but all energy conversions entail energy costs of some magnitude Continue reading
In an earlier series of posts (Fueling an industrial world and Energy and the biophysical view of economic activity: from joules to fuels) I pointed out how aggregating energy sources on the basis of their nominal heating values—as is common practice for our most prominent and influential energy information agencies at national and international scale—tends to obscure the dependencies between concrete economic infrastructure and the specific forms that energy sources take in practice. The aggregation process involves taking a highly abstract view of energy sources—a view that highlights only one narrow parameter, at the expense of most of what is important for appreciating how our physical economy functions. One of the most critical areas of omission relates to the energy costs of energy supply and use. Continue reading