The concept of a cycle economy was developed from the organic cycle:
Organic material decomposes to ultimately generate new organisms. This process
may be transferred to many nonrenewable resources, especially metals. Metals
are not so much consumed as used for a specific purpose for a limited period
of time. Copper, lead and steel may be recycled many times often with
little reduction in quality or, in the case of alloys in particular, with somewhat
lower quality after primary or secondary recycling.
Thus, it is too shortsighted to focus just on the extraction of nonrenewable resources from the solid Earth, the so-called geosphere, and their transfer to the global industrialized civilization, the so-called technosphere. According to the concept of sustainable development, the equation has to take into account all the resources of the geosphere and the technosphere.
Metal recycling rates in industrial countries vary between 30 and 55 percent of total annual metal demand and are on the increase. The larger the technospheres reserves of metal, the higher the potential for recycling. So why arent recycling levels even higher? Economic growth and metal product lifetimes are both limiting factors. The lifetime of most copper products, for example, is 30 to 50 years. Take 40 years as an average: Annual copper demand 40 years ago was 6.2 million metric tons compared to 18.7 million metric tons in 2000; so even if the total copper production from 1960 was now available as scrap, the technosphere would only cover one-third of current demand.
Unlike metals, other nonrenewable materials, such as the majority of plastics, can only be recycled with a substantial loss in quality. Other materials change in composition or can only be recycled as totally new materials. For example, cement in concrete can only be recycled as low value aggregate. Other natural resources in this category become highly dispersed, as with potash and phosphate fertilizers, or are irreversibly converted, as with fuels.
The need for natural resources
In many instances we do not need a resource itself we need its function,
or a physical or chemical property. We do not require one metric ton of copper,
for example; we need its electrical conductivity for transmitting electric power
or transferring messages via electric pulses in telephone wires. The latter
function can also be fulfilled by glass fiber cables, by directional antennae
or by mobile phones. And every technical solution has its own raw material profile.
Until recently, silver was essential in photography, but todays digital
cameras require totally different raw materials. These are just two examples
illustrating our need for properties, rather than specific resources.
There are, however, two exceptions to this rule: potassium and phosphorus. These essential plant nutrients cannot be replaced. They are as important as water, which is the most important natural resource. Its not a problem for potassium, which, with seawater as an inexhaustible source, is basically a renewable resource. But for phosphorus, finding alternative sources is not so easy. Unlike potassium, phosphate has very low water solubility, so the solution needs to be sought elsewhere maybe in improved fertilizing technology. Precision farming with better use of manure, sewage and other relevant waste, enables farmers to accurately dose the amount of phosphorus required for optimum plant growth (Geotimes, November 2003). In this case, economical use extends the availability of this essential plant nutrient.
Alternatives may be possible for the properties and functions of other resources because, in addition to all the resources in the geosphere and technosphere, we have a third resource: unlimited human ingenuity. The motor that drives the supply cycle and combines these resources to find new solutions for functions is the commodity price. If a commodity becomes scarce, prices rise in our market economies, promising rewards for those who find solutions quickly.
A good example is the 1978 cobalt shortage associated with the Shaba crisis in Zaire (now Democratic Republic of Congo), which was the worlds largest cobalt supplier. Prices skyrocketed. A few years before, the Club of Rome (a global think tank) had published its Limits to Growth report, which sensitized the political arena to raw material issues, and galvanized geological surveys and other institutions in every major industrial country to initiate studies into the sensitivity of national economies to commodity shortages. The conclusion was that chromium, cobalt and other steel alloy metals were very critical strategic commodities because they could not be substituted. Recycling options were reckoned to be limited, and in case of shortages, economic research institutes anticipated that large sectors of the economy would be affected. But when cobalt prices skyrocketed in 1978, the potential financial rewards led to the discovery of substitutes. Ferrites replaced cobalt in permanent magnets and totally changed the cobalt demand pattern.
Finding new solutions for specific functions is one way to compensate for scarce
commodities or high prices. Another approach is to find ways of using materials
more efficiently. LURGI, an engineering company based in Frankfurt, Germany,
reported in 1991 that the Eiffel Tower could be built today with just 2,000
metric tons of steel instead of the 8,000 metric tons used in 1885.
Other solutions include improving recovery rates during extraction. Horizontal directional drilling, for example, boosts oil field recovery rates from 30 percent to more than 50 percent. An improvement of 1 percent in worldwide recovery rates equals one years global oil demand.
Yet another solution is to continuously discover new deposits to maintain the status quo between proven reserves and consumption. The ratio between reserves and consumption (R/C ratio) is frequently misinterpreted as the lifetime of reserves. This fallacy is highlighted by the status of zinc, copper and oil.
Since 1955, the R/C ratios for these commodities has fluctuated around 25 for zinc, 35 for copper and 40 for oil, despite increases in consumption between 1955 and today, respectively, from 3 million to 8 million metric tons zinc; 3 million to 12 million metric tons copper; and 770 million to 3.5 billion metric tons oil.
At any given time, the R/C ratios are only statistical snapshots of a dynamic system because reserves are as dynamic as annual consumption. Reserve figures change continuously; they are dependent on many factors, including exploration intensity, statistical size distribution of the deposits, commodity price ranges, production cost structures and technological changes. For example, offshore oil fields with water depths exceeding 200 meters were barely a resource before the oil crisis in 1973. Today, developed offshore oil fields sit in water depths of more than 2,000 meters.
Even the geological nature of a deposit affects R/C ratios. Commodities in stratified deposits like potash, chromite or bauxite can be easily calculated and extrapolated. They have high R/C ratios (greater than 100 and even up to 300), whereas commodities in lenticular deposits, like zinc, lead, gold or silver have R/C ratios less than 30.
The learning process
Energy consumption is one arena in which it is not possibly to simply solve
the natural resource/sustainable development paradox by finding alternative
solutions for functions. We rely on fossil fuels, but the reserves of fossil
fuels are finite. If fossil fuels are converted into energy, they are truly
consumed. Thus, the answer in this case lies in the potential of renewable energy,
which exceeds present demand by an order of magnitude.
Although this potential is not currently economically feasible, renewable energy illustrates another important aspect in successfully solving the sustainable development paradox: We need enough time to move up the learning curve. This is the only sensible interpretation of R/C ratio history; low ratios of reserves to consumption reveal a higher need for innovation.
Developing new ideas and concepts in our technological world frequently requires time scales of around 20 years. A good example is the development of wind turbines for generating electricity in Germany. In 1983, the German Ministry of Research and Development hoped to make a quantum jump in renewable electricity generation and developed a large 3-megawatt wind turbine. It collapsed only a few weeks after commissioning. The wind turbine had been constructed by the giant aerospace industry. This disastrous first attempt was followed by new small- to medium-sized enterprises, which initially developed smaller wind turbines that worked well. It took 20 years of climbing up the learning curve before 3-megawatt-sized units were successfully built. And today, 5-megawatt wind turbines are under construction.
Learning to move up the learning curve: In Germany, it has taken 20 years for the successful construction of 3-megawatt wind turbines for generating electricity. Photo courtesy of BGR.
The critical point about finding new-function solutions for nonrenewable resources is that there is not a resource problem, but a matter of having industrial structures that give us enough time to climb up the learning curve and achieve the desired solutions. The suspected oxymoron between the use of nonrenewable resources and the requirements of sustainable development can be solved by wisely using the three realms of resources available to us: resources from the geosphere, resources from the technosphere and human ingenuity.
The epochs of the Tertiary and Quaternary periods, such as the youngest epoch
the Holocene, have the ending -cene derived from the Greek word kainós
for recent. Because humankind has become a truly geological element,
the term Anthropocene has been created for the time in which we are living.
Certainly humankind today has the same impact as nature. Mass movements in mining,
construction and other operations have been estimated to be nearly equivalent
to the volume of geological mass movements associated with erosion or the formation
of new crust via seafloor spreading (approximately 35 billion cubic meters per
Unlike nature, where mass movements are unplanned and random and can be especially destructive (volcanic eruptions or landslides), humankind can plan its mass movements and minimize its impact. Although it cannot be denied that humankind has sometimes wreaked havoc at mining locations in the past, society has also rapidly moved up the learning curve to minimize such impacts. Mines today are treated as borrowed land, where a commodity is taken out before restoring and returning the site to agricultural, forestry or industrial use.
Humankinds impact in the Anthropocene is far more critical when it comes to water and soil. Salination, the mining of fossil water in arid and semiarid areas for drinking and irrigation, and increased soil erosion due to deforestation and population growth are all critical elements for the renewable resource food. Providing food to a growing world population is a far more pressing problem than any nonrenewable resource. So the true resource paradox is not the sustainable development of nonrenewable resources, but rather that the vital elements in the Anthropocene are renewable resources.