The present age of globalised industrial societies organised by market capitalism is historically unique.

While there are many indicators that mark this time as particularly unusual, the scale of energy use stands out as an especially significant anomaly. Stripped back to its essentials, energy is what does the ‘work’ of physical transformations – changes in form and movement of matter.

On that basis it should be clear that energy availability has both enabled and constrained the types of societies that have arisen throughout history.

Fossil fuels

The world as we know it is shaped in the image of fossil fuels. Indeed, the extent of this influence extends further still, encompassing even individual and cultural identities.

Fossil sources account for around 85 percent of global primary energy supply, but more importantly, the institutions and infrastructures, the plant and equipment, the ways of organising human relations, all have oil, coal and gas embedded at their core.

When everything with which we’re familiar is so fundamentally steeped in fossil fuels, climbing out of the valley of established expectation to envisage life beyond them poses a formidable challenge. It is hardly surprising then that post-carbon futures are overwhelmingly portrayed with levels of energy abundance that have arisen only with carbon civilisation itself.

But we must climb beyond this default assumption of abundance. As a matter of biophysical inevitability, fossil fuels will become increasingly costly to produce in environmental, financial, and – very importantly – energetic terms.

One way or another, in coming years and decades, human societies will have at their disposal ever decreasing quantities of these foundational energy sources. The rate and shape of decline is subject to wide-ranging economic, technical, social, cultural and political influences. There will be twists and turns along the way, no doubt. But perhaps paradoxically, the further ahead we cast our thinking, the more certain we can be of where this trajectory must lead.

Physical transformations

These geological constraints would be challenge enough for the re-evaluation of what it means to be human. But to this we must add the diabolical task of now removing carbon-based fuels from our economies altogether, at the fastest possible rate, by choice.

Not just to maintain climate stability – a hope still widely held even recently – but now with fingers crossed that the instabilities already locked in through our past infractions can be contained sufficiently to avoid overwhelming human prospects altogether.

In our new book, Carbon Civilisation and the Energy Descent Future, we step through the case for why it is foolhardy to pin humanity’s hopes on maintaining ‘energy abundance’ through alternative energy sources and technologies.

The new IPCC report has brought to mainstream attention just how fast changes to the ways we source and use energy must be implemented. Nuclear power will scale neither far enough nor fast enough.

The heavy lifting will need to be done by renewables, principally photovoltaic and wind-generated electricity. But even with the luxury of a more relaxed timeframe, there are very sound reasons for expecting that renewably-powered societies will be dramatically different to those we know today, in terms of both the scale and the nature of energy services available, but moreover, the physical transformations that shape daily life.

Knowledge humility

The high-profile model-based renewable energy transition studies that garner widespread public attention tend overwhelmingly to feed the expectation of continuity between life as it’s currently known in the rich world, and post-carbon futures. They mesh neatly with modernity’s energy abundance, even if the worlds portrayed are leaner courtesy of belt-tightening efficiency measures.

This plays a central role in their political palatability, and likely also in their often enthusiastic media reception. Dig a little deeper though, and the research literature in this area tells a different story. Yet, at the other extreme of an often polarised discourse there is outright refutation of the possibility that technologically-sophisticated societies with long-term prospects can be powered by wind and sun alone.

While we’re not inclined to simply dismiss these views, of greater interest is the very substantial middle-ground between the ‘easy’ and ‘impossible’ poles. These are the many investigators who recognise post-carbon futures as subject to deep uncertainties, and who recognise the limits of future-oriented inquiry that employs inherently fallible and incomplete models of the world.

A critically open reading of this literature, and an interest in the foundations of human knowledge claims more broadly, leads us to the view that this is an area particularly demanding of what we term ‘knowledge humility’. To the extent that there is any present certainty here, it is that the worlds actually realised will surprise us with their differences from what is envisaged today.

This leads us to the view – open to change through ongoing learning of which actual experience related to the realisation of post-carbon societies will be central – that humanity’s best course of action is to act in the present as if renewable futures will entail energy descent. That is, a significant reduction in the energy services (work, heating, lighting, data manipulation), and hence in the physical transformations, with which human social activity is organised.

Economic deintensification

Given the tight correlation between economic activity as measured by GDP, and energy use, this implies also a transformation beyond economic growth as we know it. Energy descent futures are also futures of economic degrowth.

A default cultural narrative says that this implies deprivation and an end to human wellbeing. We say: not so fast. There is enormous scope for supporting high levels of experienced wellbeing while doing things in ways very different from those familiar in contemporary forms of political economy.

We outline approaches to this under the banner of ‘voluntary simplification’ and ‘degrowth’, but the approaches are myriad and go by many other names – for instance, permaculture.

A further example is ‘economic deintensification’ as articulated by the late David Fleming in his book Lean Logic, whereby growth of the informal – household and neighbourhood – economy is encouraged at the expense of the formal economy, so much of which serves its own bloated and distended production needs, as distinct from fulfilling the immediate wants of the people for whom it purportedly exists in the first place.

Do we see such comprehensive shifts in culture, identity and ways of life as presenting easy or painless paths? No. But we also recognise that throughout human existence, people have lived well under conditions far less energetically and materially favourable than today.

In fact, on the basis of this we might ask just how favourable these energetically and materially intense ways of life have turned out to be. The potential exists for energy descent futures to be meshed with stories of renewed hope for humanity.

These authors

Joshua Floyd is energy, systems and society fellow at The Rescope Project; Dr. Samuel Alexander, co-director of the Simplicity Institute, is a lecturer at the Office for Environmental Programs, University of Melbourne, Australia.