Chapter 6 Resources.
If we want to maintain our civilization on this planet for the longest possible time, the world will ultimately have to rely solely on our renewable resources as it is inevitable that our non-renewable resources will eventually be totally consumed. For example oil and natural gas will probably be two of the first sources of energy to become totally depleted. Currently the reserves of oil are estimated to last for about 40 years, although this figure is steadily being reduced by the oil companies. Coal and natural gas are expected to last considerably longer, although in the past year the estimate of the life of natural gas resources has also been revised downwards.. By the year 2050 therefore, our energy supply will no longer be able to rely on oil and gas. We will still have coal, which is estimated to be able to provide fuel for another 200 years. However this will require considerable work to eliminate the contaminating and greenhouse gases that are an inevitable result of burning coal. Some gas and such renewable sources as solar energy, hydro-power, geothermal, wind power and so on will be available and no doubt will become more widely used as the oil supply becomes more and more expensive. It seems likely that atomic power will become our major source of energy in spite of many of the negative reports that are publicized regarding this form of generating electricity and will continue until some other source of energy such as atomic fusion can be developed into a practical system.
But our renewable resources are also finite in that we cannot use them faster than they can be regenerated. Therefore because they are inherently limited by the rate at which they can renew themselves, some form of rationing may well be required. Developing the plans for defining who will use these resources and when they will be used, will inevitably generate disputes and it will demand considerable wisdom and understanding to control the conflicts that will occur. For example should our rivers be allowed to run free or should they be dammed to provide electric power? Do we allow the forests to remain in their natural state or will they be developed to grow timber for homes and fuel? We have to face hard facts and they are that this can only be decided once we have agreed on a world wide level of population.
We will have to decide how much land will be put aside for food and other renewable resources and where this will be located. We will have to take into account that we may not have the resources to easily and quickly transport goods over long distances once the oil supplies are exhausted. Without the oil fields as a source of synthetic rubber, we will have to revert back to the use of natural rubber and this will require that we return some of the jungle back to rubber plantations. This in turn will compete with the development of plantations for palm oil, which will become a necessity when there is little or no oil from ground sources. There are many other examples where the use of natural renewable resources for one particular purpose will conflict with other uses. Hundreds of square miles of desert may have to be covered with solar cells to provide power and this will inevitably damage the natural habitat of many animals and birds. Similarly the use of the wind to generate power will line the plains and hills with rows of windmills and will take away ground that could otherwise be used for food producing purposes as well as endangering the birds that fly into these propellers. A speaker was recently discussing alternative energy sources and claimed that wind power could supply all our electricity needs. It would cover so many thousands of acres of land he said, but throughout his talk he never mentioned the effects of the rising population, the increasing standard of living, or even the population figures he used to make his calculations. All of these must be determined and used when making these forecasts.
We generally define a particular resource as renewable or non-renewable. Non-renewable resources refer to those materials that are in limited supply and will not be replaced during the estimated lifetime of our civilization. We are primarily considering those items that were slowly produced as the world has evolved, such as the metal ores, and oil. Renewable resources on the other hand are those materials that will become renewed as a result of the natural evolution of life on this earth. Here we are considering such things as plants and trees, wind and geo-thermal power, sunshine and rain.
In many cases it will be extremely difficult to estimate just how long a particular non-renewable resource will be available. First of all we generally have to assume that its use remains the same as today and this of course will not necessarily be the case. For example consider how the development of the jet engine increased the demand for alloys that would function at high temperatures. Then supersonic aircraft initially required titanium for their skins, to be replaced with carbon fiber composites as they developed further. All of these changes involved the use of non-replaceable materials that could not have been foreseen a decade earlier. On the other hand there was recently a TV program showing that a new development showed plastics that had previously been made solely from oil that were now being made from vegetation.
Consider the increasing use of steel framing in the building industry in place of the traditional timber, as wood has become scarcer and its cost increased. Although at present it appears that there is an almost limitless supply of iron ore, we are in fact digging into our non-replaceable supplies. We are using up our timber faster than nature can replace it. On the other hand using metal in our homes and offices is not merely eating into our very plentiful supply of iron ore, it is also digging into our current non-replaceable energy supply which is being used for the smelting and processing of the metal. This is a prime example of too great a demand on our replaceable resources, our forests, forcing us to dig deeper into our non-replaceable alternative materials, iron ore. Our forests may well be some of the more important natural resources that are necessary to maintain life on this planet. We have to determine exactly how great a world population can be supplied from them, without endangering their ultimate existence.
We have to consider just how the use of our non-replaceable resources will vary as the changes in our society and technology develop. Attitudes will also have to change. Just as now we have to seek approval before we can install any process that could possibly cause pollution, in the near future we may have to seek permission before we dig deeper into any of our resources. Obviously we will have to consider every new demand on our resources and revise their estimated life with every change to the world’s population. No matter how variable are our estimates and how inaccurate, it is essential that we develop an understanding of the lifetimes of these resources and update them as necessary.
We must understand not only their lifetime but also the factors that can change this figure or it will become impossible to effectively plan for their replacements. It is a fairly simple matter to move towards using steel framing for our houses, as wood becomes scarcer. It will be much more difficult to arrive at alternative fuels to replace gasoline when the supply of oil runs out. Indeed there may be no substitute and we will then have to develop a totally different society that can operate without personal transport. By understanding the remaining lifetime of our non-replaceable resources, we can see more clearly which will run out the soonest and therefore where we need to direct our efforts to compensate for their loss.
Up until the present time we have generally used the world’s resources as they have been discovered, without any concern for the total amount available. This was understandable with the population of a century ago, but as the number of people in our world has dramatically increased we can no longer operate in this way. We have only to look back in history to find cases where a particular resource has been totally "cleaned out", such as the tin mines in Cornwell, England. These mines had been in existence since Roman times but with the adoption of the steam engine to pump the mines clear of water, and provide traction in the pits they were much more aggressively mined. With the increasing demand for the metal, the mines were soon exhausted and the supplies from the Far East soon became the prime source of tin. Steam power became practical through the development of the coal fields, another non replaceable resource, in the Northern areas of England and the border country with Scotland. The railways that enabled the coal to be easily transported were also of prime importance in developing this form of energy. In considering the supply life of any particular resource therefore we also have to recognize the other materials may be involved and recognize the effect on those particular resources.
Some resources are difficult to categorize as renewable or non-renewable, for example water. At first glance it appears ridiculous to define water as a non-renewable resource, we have all seen the rain that brings new life to the soil and fills our streams and rivers. However when we consider the deep water far below the surface of the land, it is obvious that we are pumping out this aquifer much faster than the water can be replaced. In many places where irrigation has to be used to maintain the productivity of the fields, we have seen a dramatic drop in the water table level. These supplies cannot be quickly replaced and the calculation of the time to replenish them must be part of the overall facts and figures. We are here looking at times of many years and not something that can be replaced by one or two rainstorms. So in the short term water in many areas has to be considered as a non-replaceable resource and the way that we use it carefully controlled.
When we come to calculate the life expectancy of non-renewable resources, we also must consider the materials and energy that may be required to make the final product from the raw materials. For example iron ore is of itself almost useless, it is only after the expenditure of fuel to smelt the ore that useable metallic iron becomes available. We also have to consider the amount of pollution this will produce as well as the materials, both renewable and non-renewable that are involved in controlling this pollution. For example, when we consider the automobile, it is quite easy to calculate the amount of gasoline that any car will use in its daily use. What is more difficult is to calculate the amount of energy used in its manufacture whether derived from gas, electricity or oil. Finally we have to calculate how much energy and materials have been expended in controlling contaminating emissions during the production of the raw materials and the manufacture and operation of the vehicle. In addition there are the materials used to build roads, bridges and similar facilities. All of these factors affect the use of non-renewable resources, and will increase the amount used beyond the simple measure of gasoline pumped into the tank.
We must consider our non-replaceable materials as the tools we have been given by nature to assist in developing our society, our technology and our overall way of life, in preparation for the time when these resources will no longer be available. The calculated life of these materials tells us just how long we have to complete these changes. By the time each non-renewable material has been totally consumed we must have made the necessary adjustments to compensate for its loss. In many cases the change will not be too difficult, for example to use natural rubber from trees in place of the synthetic material derived from oil. In some cases the change will be very complicated and may require a complete change in our life style. For example the changes to our transport system resulting from the end of our oil supply and the lack of plastics from this source.
It is easier to see the effects of mankind on our renewable resources if we look at some of the lands where civilization has grown fastest. In the Middle Ages timber was the only available material for building ships, and the sturdy oak trees of Great Britain were soon in demand for building the British Navy. "Hearts of oak are our ships" goes the old song that records those days. As the navies of Spain and Britain faced each other the number of trees that were cut down increased until there were insufficient to supply the required amount of timber and wood had to be obtained from other countries. In addition charcoal was then being used for the smelting of iron ore, which only further depleted the available timber. The forests were decimated and have never recovered. Here was a fine example of permanently damaging a renewable resource by removing too much, too quickly.
When a particular resource is freely available, it is very easy to assume that the supply is limitless and oil is probably the best example. Not only is it the most widely used form of energy, but many industries have been developed around the supply of oil. Plastics, chemicals, synthetic rubber, dyes and some pharmaceuticals are all largely derived from the oil.. To date there appears to be little effort to develop alternative resources that will replace oil in these fields when the supply is eventually exhausted. This is in spite of the fact that the best estimates state that this will occur in about 40 years. The world has been very well explored for this valuable commodity, and even if further oil fields are discovered it does not seem likely that this figure will increase by more than 10 or 15%
The first step that must be taken is to estimate how many people the world’s renewable resources can maintain, depending on their rate of self-renewal. This will require very careful research and planning, as each particular resource will show completely different figures. For example we may find that we have enough fresh water to maintain quite a large population compared to the number of people that can be permanently supplied with timber from our forests. Here again the number may vary depending on the building methods that are to be used. A timber-framed house will demand much more wood than a brick building, but brick requires fuel for the firing of the clay and in the manufacture of the cement used to bond the bricks.. Similarly the figures will be affected by the degree of pollution that will become acceptable based on the agreed upon population figures. Burning wood to heat our homes uses only renewable resources, but if the subsequent pollution is to be kept within limits then smoke control will be required which may involve the use of exotic metals.
None the less, even though the answers will be difficult to estimate we have to develop them. They will give us a start in defining our ultimate world population target, and when we will have to achieve this figure. If our estimate is overly optimistic then we will soon find shortages that we will be unable to fill. We may also find that we have taken more than nature can replace and effectively wiped out a renewable resource. We have already decimated some species through our uncontrolled development. This is a case where caution is absolutely necessary. Tied up with this estimated final population figure is the need to determine exactly what life style we intend to provide for our future generations.
If we are to be content to provide each family with a one roomed apartment with only the essential facilities, we can support more people than if we provide each a home complete with all the facilities that today we consider necessary. So here is the other factor that has to be entered into the equation. We have to try and visualize the type of life that will exist in the future and the options we can offer our citizens. Similarly once we calculate how much food is required, we have to consider where this is to be grown, how much fertile land is necessary and how the food is to be harvested, stored and transported. Once the oil supply is depleted we have to know how we will supply energy to the farmer to prepare and harvest his crops. Depending on our ability to supply electricity, we may find that refrigeration and long term storage of some foods will not be possible, and this may demand that food production be set up close to the centers of population. Without fuel for the internal combustion engine, or oil for the boilers of our ships, the transport of large volumes of foods from overseas may be impossible. This in turn will limit the number of people that can be supported in some of the more remote places with a less favorable climate.
The change over to our ultimate way of life will have to be carefully planned, and will occur in stages as the supply of non-renewable resources begins to impact our current civilization. For example when copper comes into short supply, this will dramatically impact our ability to provide electrical power, and transmit it over long distances. It may eventually be possible to develop other conducting materials from renewable sources but at present this does not appear likely. It is however a possibility that must not be totally forgotten and is an important research for the future
All of the above assumes that non renewable supplies of such raw materials as iron, copper and similar commonly used materials will be available for the foreseeable future. It also assumes that sound recycling becomes part of our normal way of life to prolong the availability of these resources. Unfortunately for many years, when nonrenewable resources were plentiful, recycling was rarely considered a necessity and thousands of tons of scrap materials were buried in waste sites. It may well be that in the future we will see some of these scrap materials being recovered as valuable resources.
It can be seen that this is far from a simple subject, indeed what at first appears to be a simple exercise in statistics quickly evolves into a complex decision making responsibility that will affect the lives of everyone on this planet. It demands very close cooperation between the various countries, which may ultimately be the single most difficult thing to achieve. It cannot be effective unless there is complete and universal agreement.