Friday, January 13, 2017

Peak Uranium: the uncertain future of nuclear energy

 
Alice Friedmann recently posted on her blog "Energy Skeptic" a summary of the discussion on nuclear energy from my book "Extracted" (Chelsea Green, 2014). It is a well-done summary that I am reproducing here. Note that the text below mixes some of the considerations of the main text (written by me) and of one of the "glimpses"; that were written by other authors. The glimpse that reports the results of a model of future uranium production was written by Michael Dittmar. He told me in a recent mail exchange that his model seems to be doing pretty well more than two years after its results were published in "Extracted". (U.B.)

Peak Uranium by Ugo Bardi from "Extracted: How the Quest for Mineral Wealth Is Plundering the Planet"


Figure 1. cumulative uranium consumption by IPCC model 2015-2100 versus measured and inferred Uranium resources

[ Figure 1 shows that the next IPCC report counts very much on nuclear power to keep warming below 2.5 C.  The black line represents how many million tonnes of reasonably and inferred resources under $260 per kg remain (2016 IAEA redbook). Clearly most of the IPCC models are unrealistic.  The IPCC greatly exaggerates the amount of oil and coal reserves as well. Source: David Hughes (private communication)


This is an extract of Ugo Bardi’s must read “Extracted” about the limits of production of uranium. Many well-meaning citizens favor nuclear power because it doesn’t emit greenhouse gases.  The problem is that the Achilles heel of civilization is our dependency on trucks of all kinds, which run on diesel fuel because diesel engines transformed our civilization with their ability to do heavy work better than steam, gasoline, or any other kind of engine.  Trucks are required to keep the supply chains going that every person and business on earth require, from food to the materials and construction of the roads they run on, as well as mining, agriculture, construction trucks, logging etc. 

Nuclear power plants are not a solution, since trucks can’t run on electricity, so anything that generates electricity is not a solution, nor is it likely that the electric grid can ever be 100% renewable (read “When trucks stop running”, this can’t be explained in a sound-bite).  And we certainly aren’t going to be able to replace a billion trucks and equipment with diesel engines by the time the energy crunch hits with something else, there is nothing else.


Alice Friedemann   www.energyskeptic.com  author of “When Trucks Stop Running: Energy and the Future of Transportation”, 2015, Springer and “Crunch! Whole Grain Artisan Chips and Crackers”. Podcasts: Practical Prepping, KunstlerCast 253, KunstlerCast278, Peak Prosperity , XX2 report ]

Bardi, Ugo. 2014. Extracted: How the Quest for Mineral Wealth Is Plundering the Planet. Chelsea Green Publishing.

Although there is a rebirth of interest in nuclear energy, there is still a basic problem: uranium is a mineral resource that exists in finite amounts.

Even as early as the 1950s it was clear that the known uranium resources were not sufficient to fuel the “atomic age” for a period longer than a few decades.

That gave rise to the idea of “breeding” fissile plutonium fuel from the more abundant, non-fissile isotope 238 of uranium. It was a very ambitious idea: fuel the industrial system with an element that doesn’t exist in measurable amounts on Earth but would be created by humans expressly for their own purposes. The concept gave rise to dreams of a plutonium-based economy. This ambitious plan was never really put into practice, though, at least not in the form that was envisioned in the 1950s and ’60s. Several attempts were made to build breeder reactors in the 1970s, but the technology was found to be expensive, difficult to manage, and prone to failure. Besides, it posed unsolvable strategic problems in terms of the proliferation of fissile materials that could be used to build atomic weapons. The idea was thoroughly abandoned in the 1970s, when the US Senate enacted a law that forbade the reprocessing of spent nuclear fuel.

A similar fate was encountered by another idea that involved “breeding” a nuclear fuel from a naturally existing element—thorium. The concept involved transforming the 232 isotope of thorium into the fissile 233 isotope of uranium, which then could be used as fuel for a nuclear reactor (or for nuclear warheads). The idea was discussed at length during the heydays of the nuclear industry, and it is still discussed today; but so far, nothing has come out of it and the nuclear industry is still based on mineral uranium as fuel.

Today, the production of uranium from mines is insufficient to fuel the existing nuclear reactors. The gap between supply and demand for mineral uranium has been as large as almost 50% from 1995 to 2005, though gradually reduced the past few years.

The U.S. mined 370,000 metric tons the past 50 years, peaking in 1981 at 17,000 tons/year.  Europe peaked in the 1990s after extracting 460,000 tons.  Today nearly all of the 21,000 ton/year needed to keep European nuclear plants operating is imported.

The European mining cycle allows us to determine how much of the originally estimated uranium reserves could be extracted versus what actually happened before it cost too much to continue. Remarkably in all countries where mining has stopped it did so at well below initial estimates (50 to 70%). Therefore it’s likely ultimate production in South Africa and the United States can be predicted as well.
Table 1. The European mining cycle allows us to determine how much of the originally estimated uranium reserves could be extracted versus what actually happened before it cost too much to continue. Remarkably in all countries where mining has stopped it did so at well below initial estimates (50 to 70%). Therefore it’s likely ultimate production in South Africa and the United States can be predicted as well.

The Soviet Union and Canada each mined 450,000 tons. By 2010 global cumulative production was 2.5 million tons.  Of this, 2 million tons has been used, and the military had most of the remaining half a million tons.

The most recent data available show that mineral uranium accounts now for about 80% of the demand.  The gap is filled by uranium recovered from the stockpiles of the military industry and from the dismantling of old nuclear warheads.

This turning of swords into plows is surely a good idea, but old nuclear weapons and military stocks are a finite resource and cannot be seen as a definitive solution to the problem of insufficient supply. With the present stasis in uranium demand, it is possible that the production gap will be closed in a decade or so by increased mineral production. However, prospects are uncertain, as explained in “The End of Cheap Uranium.” In particular, if nuclear energy were to see a worldwide expansion, it is hard to see how mineral production could satisfy the increasing uranium demand, given the gigantic investments that would be needed, which are unlikely to be possible in the present economically challenging times.

At the same time, the effects of the 2011 incident at the Fukushima nuclear power plant are likely to negatively affect the prospects of growth for nuclear energy production, and with the concomitant reduced demand for uranium, the surviving reactors may have sufficient fuel to remain in operation for several decades.

It’s true that there are large quantities of uranium in the Earth’s crust, but there are limited numbers of deposits that are concentrated enough to be profitably mined. If we tried to extract those less concentrated deposits, the mining process would require far more energy than the mined uranium could ultimately produced [negative EROI].

Modeling Future Uranium Supplies
Uranium supply and demand to 2030
Table 2. Uranium supply and demand to 2030

Michael Dittmar used historical data for countries and single mines, to create a model that projected how much uranium will likely be extracted from existing reserves in the years to come. The model is purely empirical and is based on the assumption that mining companies, when planning the extraction profile of a deposit, project their operations to coincide with the average lifetime of the expensive equipment and infrastructure it takes to mine uranium—about a decade.

Gradually the extraction becomes more expensive as some equipment has to be replaced and the least costly resources are mined. As a consequence, both extraction and profits decline. Eventually, the company stops exploiting the deposit and the mine closes. The model depends on both geological and economic constraints, but the fact that it has turned out to be valid for so many past cases shows that it is a good approximation of reality.
This said, the model assumes the following points:
  • Mine operators plan to operate the mine at a nearly constant production level on the basis of detailed geological studies and to manage extraction so that the plateau can be sustained for approximately 10 years.
  • The total amount of extractable uranium is approximately the achieved (or planned) annual plateau value multiplied by 10.
Applying this model to well-documented mines in Canada and Australia, we arrive at amazingly correct results. For instance, in one case, the model predicted a total production of 319 ± 24 kilotons, which was very close to the 310 kilotons actually produced. So we can be reasonably confident that it can be applied to today’s larger currently operating and planned uranium mines.

Considering that the achieved plateau production from past operations was usually smaller than the one planned, this model probably overestimates the future production.

Table 2 summarizes the model’s predictions for future uranium production, comparing those findings against forecasts from other groups and against two different potential future nuclear scenarios.

As you can see, the forecasts obtained by this model indicate substantial supply constraints in the coming decades—a considerably different picture from that presented by the other models, which predict larger supplies.

The WNA’s 2009 forecast differs from our model mainly by assuming that existing and future mines will have a lifetime of at least 20 years. As a result, the WNA predicts a production peak of 85 kilotons/year around the year 2025, about 10 years later than in the present model, followed by a steep decline to about 70 kilotons/year in 2030. Despite being relatively optimistic, the forecast by the WNA shows that the uranium production in 2030 would not be higher than it is now. In any case, the long deposit lifetime in the WNA model is inconsistent with the data from past uranium mines. The 2006 estimate from the EWG was based on the Red Book 2005 RAR (reasonably assured resources) and IR (inferred resources) numbers. The EWG calculated an upper production limit based on the assumption that extraction can be increased according to demand until half of the RAR or at most half of the sum of the RAR and IR resources are used. That led the group to estimate a production peak around the year 2025.

Assuming all planned uranium mines are opened, annual mining will increase from 54,000 tons/year to a maximum of 58 (+ or – 4) thousand tons/year in 2015. [ Bardi wrote this before 2013 and 2014 figures were known. 2013 was 59,673 (highest total) and 56,252 in 2014.]

Declining uranium production will make it impossible to obtain a significant increase in electrical power from nuclear plants in the coming decades.

Sunday, January 8, 2017

Carbon capture finally cracked? Why you can't fight climate change with Coke or Pepsi



From "powertechnology.com", an article by Julian Turner. Not wrong, is it possible that we can't discuss anything any longer without turning it into a "game changer", a "breakthrough" and all the rest? A little less hype in these reports would help a lot. 


Some time ago, I found myself trying to explain to a journalist why I opposed CO2 mining in Tuscany. I said something like, "it makes no sense that the regional government spends money to reduce CO2 emissions and, at the same time, allows this company to extract CO2 that, otherwise, would stay underground." "But", the journalist said, "I have interviewed the people of this company and they say that the CO2 they extract is not dispersed into the atmosphere - it is stored." "And where is it stored in?" I said. "They sell it to companies that make carbonated drinks." I tried to explain to him that producing Coca Cola or Pepsi is not the way to fight climate change, but I don't think he really understood.

This is typical of how difficult is to make some messages pass in the public debate. Among the many possible ways of mitigating global warming, carbon capture and sequestration (or storage) - CCS - is the least understood, the most complicated, and the most likely to lead to pseudo-solutions. Not surprising, because it is a complex story that involves chemistry, geology, engineering and economics.

About one month ago, a post by Julian Turner appeared on "Power Technology" with the rather ambitious title of "Carbon Capture Finally Cracked." The post is full of hype about a breakthrough in the process that purifies CO2 at the output or a coal-burning plant - a process called "CO2 scrubbing".  The new process, it is said, is better, less expensive, faster, efficient, and  "game changer". Mr. Sharma, CEO of the company that developed the process declared:

“TACL will be able to capture CO2 from their boiler emissions and then reuse it,” confirms Sharma. “For the end user the electricity produced by capturing carbon dioxide will be clean electricity and the steam produced will be clean energy. For that reason, we can say that it is ‘emissions-free’.”
I have no doubt that there is something good in the new process. Scrubbing CO2 using solvents is a known technology and it can surely be improved. Technology is good at doing exactly that: improving known processes. The problem is another one: is it a really an "emission-free" process? And the answer is, unfortunately, "not at all", at least in the form the idea is presented.
The problem, here, is that all the hype is about carbon capture, but there is nothing in these claims about carbon sequestration. Indeed, the article discusses "carbon capture and utilization" (CCU) and not "carbon capture and sequestration" (CCS). Now, CCS is supposed to mitigate global warming, but CCU does NOT.

Let's go back to basics: if you want to understand what CCS is about, a good starting point is the 2005 IPCC special report on the matter (a massive 443-page document). More than ten years after its publication, the situation has not changed very much; as confirmed by a more recent report. The basic idea remains the same: to transform CO2 into something that should be stable and non-polluting. And when we say "stable" we mean something that should remain stable for time spans of the order of thousands of years, at the very least. This is what we call "sequestration" or "storage".

A tall order, if there ever was one, but not impossible and, as it is often the case, the problem is not feasibility, but cost. The safest way of storing CO2 for very long times is to imitate the natural process of "silicate weathering" and transform CO2 into stable carbonates, calcium and magnesium, for instance. It is what the ecosystem does in order to regulate the temperature of the planet. But the natural process is extremely slow; we are talking about times of the order of hundreds of thousands of years; not what we need right now. We can, of course, accelerate the weathering process but it takes a lot of energy, mainly to crush and pulverize silicates. A less expensive method is "geological storage", that is pumping CO2 into an underground reservoir. And hope that it will stay there for tens of thousands of years. But it is the main aim of CCS, nowadays.

This said, the way to evaluate the feasibility and the opportunity of the whole concept of CCS is to examine the life cycle of the whole process; see how much energy it requires (its energy return for energy invested, EROEI), and then compare it with the data for alternative processes - for instance investing the same resources into renewable energy rather than in CCS (and renewable energy may be already less expensive than coal produced electricity). But it seems that this comparative analysis has not been done, so far, despite the several cost analysis performed for CCS. One thing that we can infer from the 2005 report  (see page 338) is that, even without scrubbing, the energy necessary for the whole process might be not so far away from values that would make it an exercise in digging holes and then filling them up again, as John Maynard Keynes is reported to have proposed. The situation is better if we consider geological storage, but even in this case scrubbing is only a fraction of the total cost.

At this point, you can understand what's wrong in calling the new scrubbing process a "game changer." It is not that. It is a process that improves one of the steps of the chain that leads to carbon storage, but that may have little value for CCS, unless it is evaluated within the whole life cycle of the process.

Then, in the whole article by Turner, there is no mention of CCS/storage. They only speak of carbon capture and utilization (CCU) and they say that the CO2 will be sold to another company that will turn it into soda ash (Na2CO3). This compound could then be used it for glass making, urea making, and similar purposes. But all these processes will bring back the captured CO2 to the atmosphere! No storage, no global warming mitigation - they might as well sell the CO2 to the industry that makes carbonated beverages. This is not the breakthrough we need.

So, what sense does it have to make so much noise about "clean energy," "clean electricity," and "emission-free" energy when the new process aims at nothing of that sort? Not surprising, it is all part of the "fact-free" ongoing debate.

To conclude, let me note that this new scrubbing process might just be one of those ways of "pulling the levers in the wrong direction," according to a definition by Jay Forrester. That is, it may be counter-productive for the exact purposes it had been developed for. The problem is that pure CO2 is an industrial product that has a certain market value, as the people who extract it from underground in Tuscany know very well. So far, the cost of scrubbing has prevented the exhaust of fossil-fueled plants from having a market value, but a new, efficient process could make it feasible to turn it into a saleable product. That would make coal plants more profitable and would encourage people to invest into building more of them, and that would generate no reductions in CO2 emissions! It would be even worse if the coal industry were to sell to governments their scrubbing process in order to escape carbon taxes. So, you see? Once more, the rule of unintended consequences plays out nicely.





Saturday, January 7, 2017

Photovoltaics: cultural rape?



Those of you who can read French may be interested in this rant by Nicolas Casaux at
http://partage-le.com/…/le-desastre-ecologique-renouvelabl…/

Apparently, the government of New Zealand financed a large PV installation in the Tokelau island, somewhere in the middle of the Pacific Ocean. The plant is backed up by lead batteries, so it can provide 24/24 power to the islanders. (some 1400 people). That allows islanders to have TV, high-speed Internet, and mail ordering from Amazon and Ebay.

Casaux takes all this as the reason for a screed in which he rants against renewable energy for several paragraphs, then compares PV-ization of the islands to their conversion to the Catholic religion. Basically, it is a "cultural rape" that has left the islanders dependent on a sophisticated technology of which, according to him, they had no need, having been self-sufficient for centuries and happy to bake the fish they capture wrapped in bamboo leaves, rather than in aluminum foil.

I don't say that Casaux is wrong; on the other hand, I am a little uneasy at a Westerners who claim to be sure that those islanders were happier before having PV without having asked for their opinion (It doesn't appear that he asked). I find also objectionable to use the title "renewables ecological disaster" when clearly there has been none.

On the other hand, the piece is interesting as evidence of a widespread negative attitude against renewable energy (at least in the West). It raises also a legitimate point: how is renewable energy going to affect our lives? My impression is that most of what's being said about this matter simply derives from the refusal to accept change, of any kind. But it is clear that the diffusion of PV is going to bring many changes - and big ones. And these big changes won't take place only on the island of Tokelau. 

So, take a look at Casaux's post (maybe with the help of Google translate), and maybe you can comment on it on the Cassandra blog.


Que vous vous intéressiez de près ou de loin à l’écologie, vous avez très certainement déjà discuté de ce que l’on nomme les énergies "renouvelables", notamment du solaire et de l’éolien. Symptôme d’un diagnostic mal établi, cette…

Tuesday, January 3, 2017

An update on mineral depletion: do we need mining quotas?



Currently, the problem of resource depletion is completely missing from the political debate. There has to be some reason why some problems tend to disappear from the public's radar as they become worse. Unfortunately, the depletion problem won't go away because the public is not interested in it. I discussed depletion in depth in my 2014 book "Extracted" and now Theo Henckens' updates the situation with this post based on his PhD dissertation “Managing Raw Materials Scarcity, Safeguarding the availability of geologically scarce mineral resources for future generations" (16 October 2016, University of Utrecht, The Netherlands). The full dissertation can be downloaded via the link http://dspace.library.uu.nl/handle/1874/339827.  (UB)



Scarce minerals are running out: mining quotas are needed
by Theo Henckens

To ensure that sufficient zinc, molybdenum and antimony are available for our greatgrandchildren’s generation, we need an international mineral resources agreement.

Molybdenum is essential for the manufacture of high-grade stainless steels, but at present molybdenum is hardly recycled. Yet unless reuse of molybdenum is dramatically increased, the extractable reserves of molybdenum on Earth will run out in about eighty years from now. The extractable reserves of antimony, a mineral used to make plastics more heat-resistant, will run out within thirty years.

During more than a century the use of mineral resources increased exponentially with an average between 3 and 4% annually. Can this go on, given the limited amounts of mineral resources in the earth’s crust?

TRENDS IN THE ANNUAL EXTRACTION OF SEVEN COMMODITIES



Which raw materials or minerals are scarce?

A mineral’s scarcity is expressed as the number of years that its extractable amount in the Earth's crust is sufficient to meet anticipated demand. This exhaustion period is estimated from the annual use of such mineral. I calculated the ratio between the extractable amount and the annual consumption for 65 mineral resources. My calculation is based on what is considered to be maximally extractable from the Earth’s crust. These “Extractable Global Resources” are derived from a study by the International Resource Panel of UNEP (United Nations Environmental Program) in 2011. Regarding the annual use of mineral resources I have supposed an annual growth of 3% until 2050, where after I have supposed that extraction stabilizes. The table below shows the top ten scarcest mineral resources.


TOP TEN SCARCE MINERAL RESOURCES




Exhaustion period (in years) of remaining extractable mineral resources
Important applications
Antimony
30
Flame retardants
Gold
40
Electronic components
Zinc
80
Corrosion protection
Molybdenum
80
High-grade steels
Rhenium
100
High-quality alloys
Copper
200
Electricity grid
Chromium
200
Stainless steels
Bismuth
200
Pharmaceuticals and cosmetics
Boron
200
Glasswool
Tin
300
Tins, brass



What is a sustainable extraction rate?

In my dissertation I have defined a sustainable extraction rate as follows: “The extraction of a mineral resource is sustainable, if a world population of nine billion people can be provided with that mineral resource during a period of thousand years, supposing that the average use per world citizen is equally divided over the countries of the world”. Actually, the concept of sustainability is only applicable to an activity, which can continue forever. Concerning the extraction of mineral resources, I consider a thousand years as a reasonable approach. This is arbitrary of course. But 100 years is too short. In that case we would accept that our grandchildren would be confronted with exhausted mineral resources.
A sensitivity analysis reveals that even if we assume that the extractable reserves in the Earth’s crust are ten times higher than the already optimistic assumption of the UNEP International Resource Panel, then the use of antimony, gold, zinc, molybdenum, and rhenium in industrialized countries would still have to be hugely reduced in order to preserve sufficient of these raw materials for future generations. This is particularly so if we want these resources to be more fairly shared among countries and people than is currently the case. There are also environmental and energy limits to the ever deeper and remoter search for ever lower concentrations of minerals. If we want to stretch out all the exhaustion periods in the table to 1000 years, then it can be calculated that the extraction of antimony should be reduced of 96 %, that of zinc of 82 %, that of molybdenum of 81 %, that of copper of 63 %, that of chromium of 57 % and that of boron of 44 %. This is compared to the extracted quantities in 2010. These reduction percentages are high. The question is whether that is feasible. Moreover, would the price mechanism not lead to a timely and sufficient extraction reduction of scarce mineral resources?


The price mechanism fails
One would suppose that the general price mechanism would work: the price of relatively scarce mineral resource rises quicker than the price of relative abundant mineral resources.

TRENDS IN THE REAL PRICE OF SCARCE AND NON-SCARCE MINERALS IN THE UNITED STATES 1900-2015*



* The minerals have been classified according to their scarcity. The scarce raw materials in the figure are antimony, zinc, gold, molybdenum and rhenium. The moderately scarce raw materials are tin, chromium, copper, lead, boron, arsenic, iron, nickel, silver, cadmium, tungsten and bismuth. The non-scarce raw minerals are aluminum, magnesium, manganese, cobalt, barium, selenium, beryllium, vanadium, strontium, lithium, gallium, germanium, niobium, the platinum-group metals, tantalum and mercury.

My research makes clear that the price of scarce mineral resources has not risen significantly faster than that of abundant minerals. I demonstrate in my dissertation that, so far, the geological scarcity of minerals has not affected their price trends. The explanation might be that the London Metal Exchange looks ahead for a maximum period of only ten years and that mining companies anticipate for up to thirty years. But we must look much further ahead if we are to preserve scarce resources for future generations.

Eventually, the price of the scarcest minerals will rise, but probably not until their reserves are almost exhausted and little remains for future generations.


Technological opportunities are not being exploited
Are the conclusions I reach over-pessimistic? After all, when the situation becomes dire, we can expect recycling and material efficiency to increase. The recycling of molybdenum can be greatly improved by selectively dismantling appliances, improved sorting of scrap metal and by designing products from which molybdenum can be easier recycled. Alternative materials with the same properties as scarce minerals can be developed. Antimony as a flame retardant can be replaced fairly easily by other flame retardants. Scarcity will drive innovation.

Thirty to fifty percent of zinc is already being recycled from end of life products, but although it is technologically possible to increase this percentage, this is barely happening. Almost no molybdenum is recycled. Recycling is not increasing because the price mechanism is not working for scarce minerals. In the absence of sufficient financial market pressure, how can technological solutions for recycling and substitution be stimulated?


What should happen?

I argue that what is needed is an international agreement: by limiting the extraction of scarce minerals stepwise, scarcity will be artificially increased – in effect, simulating exhaustion and unleashing market forces. This could be done by determining an annual extraction quota, beginning with the scarcest minerals. Such an international mineral resources agreement should secure the sustainable extraction of scarce resources and the legitimate right of future generations to a fair share of these raw materials. This means that agreement should be reached on reducing the extraction of scarce mineral resources, from 96 percent for antimony to 82 percent for zinc and 44 percent for boron, compared to the use of these minerals in 2010. In effect, such an agreement would entail putting into practice the normative principles that were agreed on long ago relating to the sustainable use of non-renewable raw materials, such as the Stockholm Declaration (United Nations, 1972), the World Charter for Nature (UN, 1982), and the Earth Charter (UNESCO, 2000). These sustainability principles were recently reconfirmed in the implementation report of Agenda 21 for Sustainable Development (United Nations, 2016).

Financial compensation for countries with mineral resources
Countries that export the scarce minerals will be reluctant to voluntarily cut back extraction because they would lose revenue. They should therefore receive financial compensation. The compensation scheme should ensure that the income of the resource countries does not suffer. In exchange, user countries will become owners of the raw materials that are not extracted, but remain in the ground. An international supervisory body should be set up for inspection, monitoring, evaluation and research.


Not a utopian idea
In my dissertation, I set out the case for operationalizing the fundamental principles for sustainable extraction of raw materials, which have been agreed in various international conferences and confirmed by successive conferences of the United Nations. The climate agreement, initially thought to be a utopian idea, has become reality, so there is no reason why a mineral resources agreement should not follow.



Antimony
More than 50% of the antimony annually sold is used in flame retardants, especially in plastics for electrical and electronic equipment. A third of this equipment currently contains antimony. In addition, more than a quarter of antimony sold annually is used in lead batteries. In principle, antimony in its application as a flame retardant can largely be replaced by other types of flame retardants and antimony containing lead batteries can be replaced by non-antimony containing batteries.

Gold
In addition to its use in jewelry and as security for paper money, gold is especially used in high-quality switches, connectors and electronic components.

Zinc
The main application of zinc is as a coating on another metal to protect it against corrosion. Other applications include brass, zinc gutters, rubber tires and as a micro-nutrient in swine feed.

Molybdenum
Almost 80% of the volume of molybdenum extracted per annum is used to manufacture high-grade steels that are mainly used in constructions exposed to extreme conditions such as high temperatures, salt water and aggressive chemicals. There are very few substitutes for the current applications of molybdenum, and molybdenum is difficult, though not impossible, to recycle.

Rhenium
Rhenium is mainly used in high-quality alloys, to enable them to withstand extreme temperatures. It is also used in catalysts, to give gasoline a higher octane number.

Rare Earth Metals
Scarce mineral resources should not be confused with the Rare Earth Metals that are mainly mined in China. The Rare Earth Metals are seventeen chemical elements with exotic names, such as praseodymium, dysprosium and lanthanum. The name "Rare Earths" dates from the early nineteenth century. Rare Earths are geologically not scarce, at least not if you compare their extractable global resources with their current annual usage. But of course, that could change in the future.




Who

Ugo Bardi is a member of the Club of Rome and the author of "Extracted: how the quest for mineral resources is plundering the Planet" (Chelsea Green 2014)