Energy challenges: the next thousand years
Looking forward a thousand years may be difficult, if not impossible, but at least none of us will be here to see whether any of our guesses are right or wrong. Two thousand years ago it might have been possible to guess something of the world a thousand years later; but a thousand years ago it would have been impossible to guess what the world looks like today.
There has been a steady acceleration since organized human society began: from hunter gatherers to farmers and fishermen, to town dwellers, to the creation of hierarchies in cities, and in the last 250 years to the industrial revolution. Throughout small environmental, in particular climatic, variations have been critical. Throughout the use of resources, particularly for generation of energy, has greatly affected the character of each society. In the past such energy came from
- water (and hydro power generally)
- animal including human muscle
- oil and gas
In one way or another all such sources contained environmental penalties as well as advantages. More recently energy systems have included
- terrestrial solar panels large and small
- tide round coastlines, and waves
- geothermal to make use of the heat beneath our feet
- nuclear with prospects for new fission technology (such as pebblebed), and later fusion technology using tritium and deuterium
- even use of seawater for agriculture as well as for generation of energy.
For the future there is a range of exotic possibilities which we have had fun in discussing at this conference. They include solar space power and even gravitational energy.
Earlier I referred to the acceleration of history. In this energy has played a major role. Accompanying it has been population increase on an epic scale, increasing damage to the natural environment, depletion of resources ranging from topsoils to fish stocks, accumulation of toxic wastes, pollution of water both fresh and salt, changes in the chemistry of the atmosphere with climate change, and destruction of the diversity of other living organisms on which we totally depend.
We were each of us asked what we thought the three most important factors will be in the future. As I shall explain, I doubt whether it will be energy. More important by far are human population increase and the exploitation of natural resources. Is our small animal species capable of establishing a lasting relationship of mutual benefit to the living Earth and those of its unruly inhabitants who are ourselves? How are we to recognize that the last 200 years or so may have been a bonanza of inventiveness, exploitation and consumption in countries which have learnt the tricks of industrialization, but that this may not continue, indeed cannot continue on a world wide basis?
We still cherish a consumer philosophy, and conventional economics of a kind which takes little account of externalities or true long term costs. We still talk about growth and GNP as if they were useful measures of human welfare. At present rates of consumption, we would need three planets rather than one if we had a truly equitable society.
All successful species, whether bivalves, beetles, elephants or humans can multiply until they come up against the environmental stops, reach some accommodation with the rest of the environment and willy nilly restore some balance. Malthus may yet have the last laugh. In the long history of the Earth we are the only species capable of recognizing this, and that sooner rather than later we have to do something about it. Thinking differently, particularly about economics and technology, may be painful but it is indispensable. Otherwise we risk being trapped in out of date ideas and technology (the so-called techno-locks).
Looking ahead a thousand years, we must first assume that the human species still exists. Most species have a limited time span, and with the current rate of accelerating change there is no reason to believe that the human species will last for ever. But let us peer ahead all the same. First we should recognize that so long as there are humans to generate and use it, there will never be a shortage of energy. Exploitation of fossil fuels cannot be more than temporary, and there are more possibilities than we can count to replace coal, oil and gas. We have heard a lot about them at this conference.
The key question is not which technology to go for, but how many people there are to use it, and what other resources are available to support society in any form that we can recognize. We must not therefore assume an endlessly rising curve of energy demand to satisfy the needs of a society of anything like the size of ours in the 21st century. Nor should we assume that the world will be necessarily warmer or even cooler by then. All that we can be sure of is that it will be very different.
By AD 3000 there will probably have been sudden disruptions, whether volcanic explosions, earthquakes, impacts of extraterrestrial objects, epidemics, or even destructive wars using unimaginably horrible weapons. World wide the relationship between land and sea will be different. Compare the shape of the Earth's surface 125,000 years ago in the last warm period, and then 20,000 years ago in the last glacial spasm. There will be new hubs of power, wealth and culture.
Ecosystems will be drastically changed, and agriculture to support our species with them. Already the rate of extinction of other species can be compared to those of the five great extinctions in the geological history of the last 500 million years. Human health and welfare will be affected by these changing conditions. There is a powerful synergy between pathogen transmission and environmental change. Old diseases will return, new ones will arise and spread.
How our successors will react to these new circumstances is anyone's guess. If all goes as reasonably as we must all hope, they are likely to be living in a more globalized world of rapid communication. Ideas, units of information - or memes - will pass almost instantaneously between countries, communities and individuals, and for the first time there will be something like a single human civilization.
Human numbers in cities or elsewhere will almost certainly be reduced, and their distribution will almost certainly be very different. It has been suggested that an optimum population for the Earth in terms of its resources would be nearer to 2.5 billion rather than - as now - over 6 and a half billion, or even 9 billion later this century. Communities are likely to be more dispersed without the daily tides of people flowing in and out of cities for work. Generation of energy will likewise be dispersed with more micro systems and less dependence on national or other grids. Transport systems will also be different. Archaeologists of the future may even wonder what all those roads were for.
Then there are other developments in information technology. Here come the most radical possibilities of all. So far evolution has proceeded by natural selection in its various aspects. In the last few thousand years humans have played games with it through artificial breeding of organisms - from cereals to cows and dogs - to suit their purposes. Such processes were always slow. But now through lateral gene transfer, humans may rapidly be producing new varieties, sub species and even new species. This could apply to humans themselves.
H. G. Wells invented Eloi and Morlocks (those up above and those down below). At the time, more than a century ago, it seemed an amusing fantasy. No longer. Redesigning humans has become a real possibility. It is worth remembering how vulnerable even the Eloi were. In his book The Meaning of the 21st Century James Martin suggested that there were three broad patterns of evolution. First there is primary evolution, or the Darwinian process of mutation, drift, symbiosis and natural selection of species over billions of years. Next comes secondary evolution, by which, in the author's words
" ... An intelligent species learns how to create its own form of evolution. It invents an artificial world of machines, chemical plants, software, computer networks, transport, manufacturing processes, and so on. It learns how to manipulate DNA ... There is a great diversity of evolutionary tracks."
Thirdly there is tertiary evolution in which an intelligent species learns to automate evolution itself. Once initiated, this could take place with great speed, and could lead to what is called a singularity with unknowable but possibly explosive results.
Obviously we are now somewhere into stage two, but stage three may well lie before us. The challenges and risks are enormous. It does not mean that computers will eventually become more intelligent than people, but it does mean the creation of a new kind of intelligence with a variety of associations with the human brain. Whether all this awaits us remains to be seen.
It also remains to be seen whether by 3000 humans will have worked out, and will practice an ethical system in which the natural world has value not only for human welfare but also for and in itself. They may also be involved in spreading life beyond the Earth and colonizing Mars or other planets. The opportunities for our species seem as boundless as the hazards.
I sometimes wonder how long would it take for the Earth to recover from the human impact? How soon would our cities fall apart, soils regenerate, the animals and plants we have favoured find a more normal place in the natural environment, the waters and seas become clearer, the chemistry of the air return to what it was before we polluted it? Life itself, from the bottom of the seas to the top of the atmosphere, is so robust that the human experience could become no more than a short and certainly peculiar episode in the history of life on Earth.
Above all let us remember how small and vulnerable we are as creatures of a particular environment at a particular moment in time. We are like microbes on the surface of an apple, on an insignificant tree, in an insignificant orchard, among billions of other insignificant orchards stretching over horizons beyond our sight or even our imagining.