The peak oil crisis: sustainability
It does not take much thinking about the implications of peak oil before the concept of sustainability arises.
For many centuries now mankind has been using the earth's resources - trees, fertile soils, wildlife, and fossil fuels - at a prodigious rate and they are just about gone. Some of these resources such as trees, fertile soil and fish can be restored in a few decades, or perhaps centuries, with good conservation practices. Others, such as fossil fuels and some minerals are close to being gone -- period. Some of our minerals can be recycled and as time goes more and more probably will. It is the energy that is going to be a problem.
We all know about renewables - solar, moving air, moving water, biofuels, and geothermal heat. The rest of the 21st century or perhaps longer is going to be about shifting life to sustainable sources of energy and phasing out the fossil fuels.
Food production is frequently discussed as the key area of human endeavor that will need to become sustainable if we are to continue eating. For the last hundred years agricultural production has boomed as we have dumped vast amounts of petroleum-derived chemicals and pesticides on the world's crops. Then we have piled the resulting crops into fossil fuel powered trains, planes, ships, and trucks and after much energy intensive processing and packaging have delivered them to consumers 1,000s of miles away. This too will have to be phased out as the energy involved in all this becomes so expensive that we can no longer afford to eat. Many see the return to sustainable agricultural practices in the midst of global warming as by far the biggest challenge our descendents will face.
There is, however, more to the sustainability problem than just renewable energy, transportation and food - and that is our infrastructure. Large agglomerations of people living under reasonable conditions in the 21st simply cannot continue in a healthy, sustainable state without clean water, sewage, electricity, communications, a source of warmth and a transportation network to move life-sustaining supplies about. Most of the infrastructure in use today has been built in the last 150 or so years.
Moreover, much has never been rebuilt. There are 100's of thousands of miles of water, sewer, oil, and natural gas pipelines - most in very hard to reach places that are getting very old. In the next 50 to 100 years most if not all of these vital arteries are going to have to be replaced. Then there is the electric grid, parts of which have been around for 100 years, and the roads, bridges, and rail lines that need to be maintained on a sustainable basis.
If our lifestyles are to continue in any semblance of what the developed countries have known for the last 100 years, massive efforts are going to have to expended on ways to make our infrastructure - buildings, utilities and communications -- sustainable. This is not impossible, but it is going to take a much larger share of our resources than that to which we have become accustomed.
In many places, particularly south Asia, the electric grid that was never built or maintained at North American or European standards is already nearing collapse with power available less than half the time. To the credit of the Obama Administration, it has recognized that the national electric grid will become of increasing importance and has allocated some $40 billion in stimulus funds to begin a overhaul. Most will have figured out by now that once the oil becomes too expensive, except for some biofuels and draft animals, it is going to be electricity and the human muscle for there will be not much else.
Can an electric grid be maintained on a sustainable basis? While electricity can be generated locally, a lot of the best renewable resources are in places where the people aren't. In the case of the U.S., the southwestern deserts will provide the best source of solar power and the Great Plains, Great Lakes, mountain tops, and sea coasts the best sources of wind generated power.
I suspect that our descendents are going to figure out that maintaining and renewing the electric grids are going to be one of the best uses for earth's supply of metal and with good recycling policies can probably be made to last for a very long time.
The underground pipe network is a jumble of systems, ownership and ages. Ownership is a mixture of local governments who usually supply water and sewage, corporations that move natural gas, and in some places electricity, communications, and other liquids below the earth. Making these networks which are dying of old age and making them sustainable is going to be more of a problem than rebuilding the electric grid. Rather than tackling this piecemeal, one approach would be to design and start building an integrated tunnel system that would be designed to last for a very long time and that would carry all the utilities - water, sewer, gas, electricity, communications, perhaps even heating and cooling fluids or hydrogen. Expensive? Massively! Flexible? Definitely! Sustainable? Perhaps!
We then come to the problem of sustainable roads and buildings. Without cheap, plentiful asphalt, and other petroleum based products, maintaining traditional road nets is going to become difficult. Concrete may do for awhile, but in the long run that will be a problem. Gravel and stone just might make a comeback.
Buildings that will last for a very long time are a more interesting problem. Obviously the energy requirements are going to need to be a small fraction of what is being consumed today if they are to be supplied from renewable sources. Wood can be renewed. Stone and brick are more permanent. Oil-based paint may just become too expensive. High-rises? Possible but there may be better uses for the metal. Maybe our descendents will just move underground.