CHAPTER 1
Our Hunger for Energy
Most people will have heard of the cult TV series, Star Trek. Thanks to this programme, we know that in the not-too-distant future humans will start exploring the infinite expanses of the universe. The energy issue will have been resolved long before then. The Warp drive discovered in 2063 provides unlimited energy that Captain Kirk uses to steer the starship Enterprise at speeds faster than light to new adventures. Energy is available in overabundance; peace and prosperity rule on Earth and environmental problems are a thing of the past. But even this type of energy supply is not totally without its risks. A warp core breach can cause as much damage as a core meltdown in an ancient nuclear power plant. Warp plasma itself is not a totally safe material, as the regular viewers of Star Trek very well know.
Unfortunately – or sometimes fortunately – most science fiction is far removed from the real world. From our perspective the discovery of a warp drive seems highly unlikely, even if dyed-in-the-wool Star Trek fans would like to think otherwise. We are currently not even close to mastering comparatively simple nuclear fusion. Consequently, we must rely on known technology, whatever its drawbacks, to solve our energy problems.
In reality, energy use has always had a noticeable impact on the environment. Looking back today, it is obvious that burning wood was less than ideal, and that the harmful noxious fumes created by such fires considerably reduced the life expectancy of our ancestors. A fast-growing world population, increasing prosperity and the hunger for fuel that has developed as a consequence have led to a rapid rise in the need for energy. Although the resulting environmental problems may only have affected certain regions, the effects of our hunger for energy can now be felt around the world. Overconsumption of energy is the main trigger for the global warming that is now threatening to cause devastation in many areas of the world. However, resignation and fear are the wrong responses to this ever-growing problem. There are alternative energy sources to be tapped. It is possible to develop a long-term safe and affordable energy supply that will have only a minimal and manageable impact on the environment. This book describes the form this energy supply must take and how each individual can contribute towards a collective effort to halt climate change. But first it is important to take a close look at the causes of today's problems.
1.1 Energy Supply – Yesterday and Today
1.1.1 From the French Revolution to the Early Twentieth Century
At the time of the French Revolution at the end of the eighteenth century, animal muscle power was the most important source of energy. Around 14 million horses and 24 million cattle with an overall output of around 7.5 billion watts were being used as work animals [Köni99]. This corresponds to the power of more than 100 000 mid-range cars.
Power and Energy, or the Other Way Around
The terms ‘power’ and ‘energy’ are closely linked, and for this reason they are often confused with one another and used incorrectly.
Energy is stored work; thus, the possibility to perform work. It is identified by the symbol E. The symbol for work is W.
Power (symbol: P) indicates the time during which the work is to be performed or the energy used.
For example, if a person lifts a bucket of water, this is considered work. The work that is performed increases the potential energy of the bucket of water. If the bucket is lifted up twice as quickly, less time is used and the power is doubled, even if the work is the same.
The unit for power is the watt (abbreviation: W) (The fact that the abbreviation for watt is the same as the symbol for work does not simplify matters.)
The unit for energy is watt second (Ws) or joule (J). Other units are also used for energy. Appendix A.1 provides the conversion factors between the different units of energy.
As the required powers and energies are often very high, prefixes such as mega (M), giga (G), tera (T), peta (P), and exa (E) are frequently used (see Appendix A.1).
The second staple energy source at this time was firewood, which was so important that it probably changed the political face of Europe. It is believed today that the transfer of the Continent's centre of power from the Mediterranean to north of the Alps came about because of the abundance of forests and associated energy potential there. Although the Islamic world was able to maintain its position of power on the Iberian peninsula well into the fifteenth century, one of the reasons why it lost its influence was the lack of wood. The problem was that there was not enough firewood that could be used to melt down metal to produce cannons and other weapons. This goes to show that energy crises are not just a modern phenomenon (Figure 1.1).
Figure 1.1 Firewood, working animals, wind and water power supplied most of the energy needed in the world as late as the eighteenth century.
In addition to muscle power and firewood, other renewable energies were used intensively until the beginning of the twentieth century. Between 500 000 and 600 000 water mills were in operation in Europe at the end of the eighteenth century. The use of wind power was also widespread, particularly in flat and windy areas. For example, the United Netherlands had around 8000 working windmills at the end of the seventeenth century.
For a long time, fossil energy sources were only of secondary importance. Although coal from underground deposits was known to be a source of energy, it was largely avoided. It was not until a lack of wood in certain areas of Europe led to energy shortages that coal deposits began to be exploited. In addition, the higher energy density of coal proved to be an advantage in the production of steel. In 1800, 60% of coal was used to provide domestic heat, but 40 years later far more coal was used in ironworks and other factories than in homes.
Fossil Energy Sources – Stored Solar Energy
Fossil energy sources are concentrated energy sources that evolved from animal and plant remains over very long periods of time. These sources include oil, gas, hard coal, brown coal, and turf. The base materials for fossil energy sources could only develop because of their conversion through solar radiation over millions of years. In this sense, fossil energy sources are a form of stored solar energy.
From a chemical point of view, fossil energy sources are based on organic carbon compounds. Burnt in conjunction with oxygen, they not only generate energy in the form of heat, but also always produce the greenhouse gas carbon dioxide as well as other exhaust gases.
In around the year 1530, coal mines in Great Britain were producing about 200 000 tons of coal annually. By 1750 it was about 5 million tons, and in 1854 an astonishing 64 million tons. By 1900 three countries, Britain, the USA, and Germany, had an 80% share of world production [Köni99].
Renewable Energies – Not That New
The supplies of fossil energies, such as oil, natural gas, and coal, are limited, and they will be depleted within a few decades and cease to exist. Renewable energy sources, on the other hand, ‘renew’ themselves on their own. For example, if a hydropower plant takes the power of the water from a river, the river will not stop flowing. The energy content of the river renews itself on its own because the sun evaporates the water and the rain feeds the river again.
Renewable energies are also referred to as ‘regenerative’ or ‘alternative’ energies. Other renewable energies include wind power, biomass, the natural heat of the earth, and solar energy. Even the sun will eventually disappear in around four billion years. Compared to the few decades that fossil energy sources will still be available to us, this time period seems infinitely long.
Incidentally, renewable energies have been used by mankind for considerably longer than fossil fuels, although the current systems for using these fuels are vastly more advanced than in the past. Therefore, it is not renewable energies that are new, but rather the knowledge that in the long term renewable energies are the only option for a safe and environmentally compatible energy supply.
At the end of the twentieth century, worldwide coal production reached almost four billion tons. With an overall share of less than 3% of the world market, Germany and Britain had lost their former position of supremacy in the coal industry. China and the USA are currently the main coal-producing countries by a considerable margin. Most of the coal produced today is used in power plants.
1.1.2 The Era of Black Gold
Like coal, oil consists of conversion products from animal and plant substances, the biomass of primeval times. Over millions of years plankton and other single-celled organisms were deposited in sea basins. Due to the lack of oxygen, they were unable to decompose. Chemical processes of transformation eventually turned these substances into oil and gas. The biomass that was originally deposited originated from the sun, which means that fossil energy sources like coal, oil, and gas are nothing more than long-term conservers of solar energy. The oldest oil deposits are around 350 million years old. The area around the Persian Gulf where most oil is exploited today was completely below sea level 10–15 million years ago.
The oil deposits were developed much later than coal, because for a long time there were no practical uses for this liquid energy source. Oil was used in small quantities for thousands of years for medicinal and lighting purposes, but its high flammability compared to coal and charcoal gave it the reputation of being a very dangerous fuel. At the end of the nineteenth century petroleum lamps and later the invention of internal combustion engines finally provided a breakthrough.
Industrial oil production began in August 1859, as the American Edwin L. Drake struck oil whilst drilling at a depth of 20 m near Titusville in the US state of Pennsylvania. One name in particular is linked with further oil exploitation in America: John Davison Rockefeller. In 1862 at the age of 23 he founded an oil company that became Standard Oil and later the Exxon Corporation and incorporated large sections of the American oil industry.
However, it was still well into the twentieth century before fossil energy supplies, and specifically oil, dominated the energy market. In 1860 about 100 000 tons of oil were produced worldwide; by 1895 it was already 14 million tons. German government figures reveal that in 1895 there were 18 362 wind engines, 54 529 water engines, 58 530 steam engines and 21 350 internal combustion engines in use in the country [Gasc05]. Half of the drive units were actually still operated using renewable energy sources.
There was a huge rise in oil production in the twentieth century. By 1929 output had already risen to over 200 million tons and in the 1970s it shot up to over three billion tons (Figure 1.2). Today oil is the most important energy source of most industrialized countries. An average German citizen, including infants and pensioners uses 1700 l every year. This amounts to 10 well-filled bathtubs.
Figure 1.2 Oil production since 1860.
Being too dependent on a single energy source can become a serious problem for a society, as history shows. In 1960 OPEC (Organization of Petroleum Exporting Countries) was founded, with headquarters in Vienna. The goal of OPEC is to coordinate and standardize the oil policies of its member states. These include Algeria, Ecuador, Gabon, Indonesia, Iraq, Qatar, Kuwait, Libya, Nigeria, Saudi Arabia, Venezuela, and the United Arab Emirates, who between them at the end of the twentieth century controlled 40% of worldwide oil production. As a result of the Yom Kippur war between Israel, Syria, and Egypt, the OPEC states cut back on production in 1973. This led to the first oil crisis and a drastic rise in oil prices. Triggered by shortfalls in production and uncertainty after the revolution in Iran and the ensuing first Gulf War, the second oil crisis occurred in 1979 with oil prices rising to USD38 per barrel.
The drastic rise in oil prices set back world economic growth and energy use by about four years. The industrialized nations, which had become used to low oil prices, reacted sharply, resulting in schemes such as car-free Sundays and programmes promoting the use of renewable energies. Differences between the individual OPEC states in turn led to a rise in production quotas and a steep drop in price at the end of the 1980s. This also sharply reduced the commitment of the industrialized nations to use renewable energies.
From Alsatian Herring Barrels to Oil Barrels
Commercial oil production in Europe began in Pechelbronn in Alsace (now France) in 1735. Barrels that had previously been used to store herrings were cleaned and then used to store the oil, because in those days salted herring was traded in large quantities, which meant the barrels were comparatively cheap. As oil production increased, special barrels of the same size were produced exclusively for oil. The bottom of the barrels was painted blue to prevent any confusion with barrels used for food products. When commercial oil production began in the USA, the companies copied the techniques used in the Alsace region. This also included the standard size of herring barrels. Since then the herring barrel volume has remained the international measuring unit for oil. The abbreviation of barrel is bbl, which stands for ‘blue barrel’ and means a barrel with a blue base.
1 petroleum barrel (US) = 1 bbl (US) = 158.987 l (litres)
The dramatic collapse in the price of crude oil from almost USD40 a barrel to USD10 created economic problems for some of the production countries, and also made it unattractive to develop new oil sources. In 1998 unity was largely restored again among the OPEC states. They agreed on lower production quotas in order to halt any further drop in prices. In fact, prices rose even higher than originally intended. Now the lack of investment in energy-saving measures was coming home to roost. The economic boom in China and in other countries further boosted the demand for oil to such an extent that it was difficult to meet and, as a consequence, oil prices kept climbing to new record highs. Even though the oil price has fallen sharply again since the financial crisis, new record prices are expected again due to the limited supplies available.
Yet, there have been some fundamental changes since the beginning of the 1980s. In many industrialized countries, energy use has decreased despite rapid and sustained economic growth. The realization has set in that energy use and gross national product are not inextricably linked. It is possible for prosperity to increase even if energy use levels or drops. Nonetheless, the chance to develop true alternatives to oil and to make energy-saving options the norm was missed due to the long period of continuous low oil prices.
This is particularly apparent in the transport sector where cars became faster, more comfortable, heavier, and with more horsepower, but only minimally more fuel-efficient. Today, the fortunate drivers of company cars with 50 hp more than 20 years ago, regularly get stuck in traffic jams (made bearable by air-conditioning and high-tech stereo systems). The tank is also bigger, so that the heavier car, with virtually unchanged consumption, can reach the next petrol station selling cheap fuel. As a result of all the talk about climate change and high oil prices, car manufacturers are now scrambling to incorporate features into their cars that have not been demanded in decades: fuel efficiency and low emissions of greenhouse gases. Since many car companies are struggling with the new requirements, they continue to rely on tried and tested concepts. Because of their political influence, they are able to prevent or dilute the strict savings targets urgently needed for climate protection. Or, like the VW Group, they try to circumvent existing regulations with illegal methods. If Volkswagen had invested the fines paid in the USA in the development of emission-free electric cars, the company would no doubt have been a world leader in this field and would also have made an enormous contribution to climate protection. In retrospect, it is likely the VW scandal will turn out to be a great stroke of luck for Germany. It has shown the technical saving limits of conventional combustion engines and considerably accelerated the switch to electric cars. In the end, it may even have prevented German car makers from falling behind internationally by uncompromisingly sticking to old technologies.
As important as oil is as a fuel, that is not its only use, because it is also an important raw material for the chemical industry. For example, oil is used as a basic material in the production of plastic chairs, plastic bags, nylon tights, polyester shirts, shower gels, scents, and vitamin pills.
1.1.3 Natural Gas – The Newest Fossil Energy Source
Natural gas is considered to be the cleanest fossil energy source. When natural gas is burnt, it produces fewer harmful substances and climate-damaging carbon dioxide than oil or coal. However, this does not change the fact that the combustion of natural gas also produces far too many greenhouse gases for effective climate protection.
The base material for the creation of natural gas was usually green plants in the flat coastal waters of the tropics. The Northern German lowland plains were part of this area 300 million years ago. The lack of oxygen in coastal swampland prevented the organic material from decomposing and so it developed into peat. As time went by, new layers of sand and clay were deposited on the peat, which during the course of millions of years turned into brown and bituminous coal. Natural gas then developed from this due to the high pressure that exists at depths of several kilometres and temperatures of 120–180 °C.
However, natural gas does not consist of a single gas, but rather a mixture of different gases whose composition varies considerably depending on the deposit. The main component is methane, and the gas also often contains relatively large quantities of hydrogen sulphide, which is poisonous and even in very small concentrations smells of rotten eggs. Therefore, natural gas must often first be purified in processing plants using physiochemical processes. As natural gas deposits usually also contain water, the gas must be dried to prevent corrosion in the natural gas pipelines (Figure 1.3).
Figure 1.3 Left: Building a natural gas pipeline in Eastern Germany. Right: Storage facility for 4.2 billion m3 of natural gas in Rehden, 60 km south of Bremen.
Source: Photos: WINGAS GmbH.
Natural gas was not seen as a significant energy source until relatively recently. It was not until the early 1960s that natural gas was promoted and marketed in large quantities. The reasons for this late use of natural gas compared to coal and oil is that extracting it requires drilling to depths of several thousand metres. It also requires complicated transport. Whereas oil was initially still being transported in wooden barrels, gas requires pressure storage or pipelines for its transport. Nowadays, pipelines extend for thousands of kilometres from the extraction sites, all the way to providing gas heating to family homes. The world's largest gas producer is Russia, followed by the USA, Canada, Iran, Norway, and Algeria.
However, the demand for natural gas is not constant over the whole year. In countries with cold winters the demand in winter is often double what it is in summer. As it is not economical to cut summer production by a half, enormous storage facilities are needed to balance the uneven seasonal demand. So-called salt caverns and aquifer reservoirs are used. Caverns are shafts dug in underground salt deposits from where the stored gas can quickly be extracted – for instance, to cover sudden high demand. Underground aquifer reservoirs are suitable for the storage of particularly large quantities of gas. Hence this rock is again filled with what it had stored for over 300 million years and taken from it in a few decades. In total, Germany has a natural gas storage capacity amounting to more than 30 billion cubic metres in operation, in planning or under construction. This corresponds to a cuboid with a base area of 20 by 20 km and a height of 75 m. Environmentally compatible hydrogen is expected to play an important role in future energy supply in the foreseeable future. The existing natural gas storage facilities are already sufficient to compensate for seasonal fluctuations in a completely renewable energy supply. Therefore, natural gas storage facilities and networks will very soon play a central role in securing a sustainable energy supply in the future.
1.1.4 Nuclear Power – Split Energy
In December 1938 Otto Hahn and Fritz Strassmann split a uranium nucleus on a simple laboratory bench at the Kaiser-Wilhelm Institute for Chemistry in Berlin-Dahlem, thereby laying the foundation for the future use of nuclear energy. The laboratory bench can still be admired today at the Deutsches Museum in Munich.
In the experiment a uranium-235 nucleus was bombarded with slow neutrons. The nucleus then split, producing two atomic parts, krypton and barium, as well as two or three other neutrons. With a large quantity of uranium-235, these new neutrons can also split uranium nuclei that in turn release neutrons, thus leading to a chain reaction. If enough uranium is available, the uncontrolled chain reaction will create an atomic bomb. If the speed of the chain reaction can be controlled, uranium-235 can also be used as fuel for power plants.
Germany as an Example of Nuclear History
The Paris Treaty of 5 May 1955 allowed Germany non-military use of nuclear energy. Expectations for the nuclear industry ran high. A separate ministry for nuclear energy was created, and the first minister was Franz Josef Strauss. On 31 October 1957, Germany put its first research reactor, called the nuclear egg, into operation at the Technical University in Munich. In June 1961 the Kahl nuclear power plant fed electricity into the public grid for the first time. In 1972 the Stade and Wuergassen commercial nuclear power plants began to provide electricity, and with Biblis the world's first 1200 MW block went into operation in 1974. In 1989 the last new power plant, Neckarwestheim, was connected to the grid. Until that point the federal government had invested over 19 billion euros in the research and development of nuclear energy. However, public concerns about the risks of nuclear energy continued to grow and prevented the building of new power plants. In 2000, Germany decided to phase out nuclear power. In 2011, another federal government significantly extended the operating times again, but the phase-out was reinstated in the same year, following the accidents at the Fukushima nuclear power plant. The last nuclear power plant in Germany is scheduled to be disconnected from the grid in 2022. Despite more than 50 years of nuclear energy use in Germany, the problem of end storage for highly radioactive waste has still not completely been resolved.
In nuclear fission there is a so-called mass defect, i.e. the total mass of the fission particles is less than that of the original uranium nucleus. A complete fission of 1 kg of uranium-235 produces a mass loss of a single gram. This lost mass is then completely converted into energy. An energy mass of 24 million kilowatt hours is thereby released. Around 3000 tons of coal would have to be burnt to release the same amount of energy.
After Hahn's discovery the use of nuclear energy was promoted mainly by the military. Albert Einstein, who emigrated to the USA in 1933 to escape Nazi persecution, sent a letter to US president Roosevelt on 2 August 1939 warning him that Hitler's Germany was making a serious effort to produce pure uranium-235 that could be used to build an atomic bomb. When the Second World War broke out on 1 September 1939, the American government set up the Manhattan Project with the aim of developing and building an effective atomic bomb.
The biggest problem turned out to be the ability to produce significant quantities of uranium-235 to maintain a chain reaction. If metallic uranium is refined from uranium ore, there is a 99.3% probability that it will consist of heavy uranium-235. This is practically useless for producing a bomb. It even has the characteristic of decelerating and absorbing neutrons, thus bringing any kind of chain reaction to a halt. Only 0.7% of available uranium consists of uranium-235, which must be enriched proportionally higher to create a chain reaction. No separation between uranium-235 and uranium-238 can be achieved by chemical means because chemically both isotopes are totally identical. Consequently, other solutions had to be sought. Ultimately, this separation succeeded through the use of a centrifuge, because the isotopes have different masses.
The Manhattan Project cost more than USD2 billion between 1939 and 1945. The desired results were finally achieved under the direction of the physicist J. Robert Oppenheimer: on 16 July 1945, two months after the capitulation of Germany, the first test of the atomic bomb was carried out in the US state of New Mexico. Using the bomb on Germany was no longer up for discussion, but shortly before the end of the Second World War the atomic bomb was dropped on the Japanese cities Hiroshima and Nagasaki – with the well-known aftermath.
The non-military use of nuclear energy came some years later. Although physicists like Werner Heisenberg and Enrico Fermi had been conducting tests in reactors since 1941, it was not until December 1951 in Idaho that the research reactor EBR 1 succeeded in generating electric current using nuclear energy.
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Friends of the Earth Germany info Satirical site on the use of nuclear energy IEA Power Reactor Information System World Information Service on Energy News and information about the UK nuclear industry |
Unlike the uncontrollable chain reaction that occurs when an atomic bomb explodes, nuclear fission in a nuclear power plant should occur in a controlled manner. Once a chain reaction has started, the number of new neutrons resulting from the nuclear fission must be kept to a limit. Each splitting of a uranium nucleus releases two to three neutrons, only one of which is allowed to split another nucleus. Control rods that capture the neutrons reduce the number of neutrons released. If this number is too high, the process gets out of control. The nuclear power plant then starts to act like an atomic bomb and an uncontrolled chain reaction occurs. Technically (and this was the prevailing view at the time), nuclear fission can be controlled, and undesired reactions eliminated.
The early euphoria that came with the use of nuclear energy died down when an accident occurred with a reactor on 28 March 1979 in Harrisburg, the capital of the US state of Pennsylvania. Large amounts of radioactivity escaped. Many animals and plants were affected and the number of stillbirths among the nearby population increased dramatically after the tragedy.
On 26 April 1986 another serious accident occurred in a nuclear reactor at Chernobyl, a city in the Ukraine. What was thought to be officially improbable actually happened: the chain reaction got out of control and the result was a nuclear meltdown. The radioactivity that was released produced high radiation levels in places as far away as Germany. Many helpers who tried to contain the damage on site paid for their efforts with their lives and thousands of people died of cancer in the years that followed.
On March 11 2011, the Japanese nuclear power plant Fukushima Daiichi was hit by a strong earthquake and a severe tsunami. The plant was not designed for such an event, and the reactor cooling system failed. As a result, nuclear melts and several explosions occurred, which destroyed four of the six reactors and released considerable amounts of radioactivity. Around 150 000 residents of the area were evacuated and hundreds of thousands of animals, which had been left behind, starved to death.
Another problem with the civilian use of nuclear energy is the disposal of radioactive waste. The use of uranium fuel elements in nuclear power plants produces large quantities of radioactive waste that will create a deadly threat for centuries to come. No safe way has yet been found to dispose of this waste.
Technically, the use of nuclear energy is fascinating and the prospect of generating electricity from relatively small amounts of fuel is very tempting. But there are serious risks involved. Germany has therefore agreed to a general decommissioning of its nuclear energy plants. Once the last nuclear energy plant has been switched off, the country's venture into this field will have cost the German federal government alone more than 40 billion euros in research and development. Germany's most expensive leisure park has become a bizarre showpiece for the incredibly bad investment in nuclear energy. The prototype for a fast breeder reactor was erected at a cost of four billion euros in the North Rhine-Westphalian town of Kalkar. Due to safety concerns, including those relating to the highly reactive cooling agent sodium, the nuclear plant was never put into operation. Today the Kernwasser Wunderland Kalkar leisure park is located in the industrial ruins of the nuclear plant (Figure 1.4).
Figure 1.4 The Kernwasser Wunderland leisure park is in the grounds of a fast breeder reactor in Kalkar that was never put into operation. Source: Photos: Wunderland Kalkar, www.wunderlandkalkar.eu.
Conservative politicians and some companies have repeatedly cited nuclear energy as a technology of the future. However, only a small proportion of the many projects announced in recent years have been implemented. Above all, the enormous costs of new nuclear power plants usually quickly end any nuclear dreams. High subsidies are necessary in order to facilitate new nuclear power plants in Europe. For the controversial new Hinkley Point C project in Great Britain, guaranteed electricity prices have been offered that are significantly higher than those for solar and wind power plants. If nuclear energy, which after all is a highly controversial technology, can no longer even offer economic benefits, its days are certainly numbered.
In 2017 there were 449 nuclear power plants in operation worldwide. Yet nuclear energy is relatively unimportant for the global supply of energy. Its share is lower than hydropower and much lower than firewood. If a major effort were made to replace the majority of fossil power plants with nuclear energy, uranium supplies would be depleted within a few years. In this sense, nuclear power plants are not a real alternative when it comes to protecting the environment – although this is how some politicians, and specifically the companies that would profit from the use of nuclear power, often like to present the option to the public.
In the long term there are high hopes for a totally new variant of atomic energy: nuclear fusion. The model for this technology is the sun, which releases its energy through a nuclear fusion of hydrogen nuclei. The aim is to duplicate this process on Earth without the danger of triggering an undesirable chain reaction like Chernobyl or Fukushima. But there is a hitch to this plan: the particles must be heated to temperatures of several million degrees centigrade to initiate the momentum of nuclear fusion. There is no known material that can permanently withstand such temperatures. Therefore, other technologies, such as the use of strong magnetic fields to contain reaction materials, are being tested. These technologies have seen some success, but despite the enormous amounts of energy used during the ignition, the reactors always go out by themselves.
Currently no one has seriously predicted whether this technology will ever actually work in practice. Critics point out that the proponents of nuclear fusion have been saying for years that it will take 50 years for a commercial functioning reactor to be connected to the grid. Despite the passage of time that 50-year time frame never reduces – the only thing about nuclear fusion that can be said with any certainty.
However, even if this technology became advanced enough to use, there are two good reasons for opposing the development of nuclear fusion. Firstly, this technology is decidedly more expensive than nuclear fission today. As already mentioned, financing conventional nuclear power plants is difficult today. For economic reasons, preference would be given to alternatives such as renewable energies. Greater investment in fusion testing means less investment in alternative energies. At present we would be happy if we could get a fusion reactor up and running at all. The use of this technology for balancing the grid is therefore hardly conceivable from today's perspective. However, this is precisely what would be needed for fusion power plants to operate in conjunction with renewable power plants, such as solar and wind. Fusion technology is therefore unsuitable for the age of renewables. Not to mention the fact that nuclear fusion plants also produce radioactive substances and waste that present a risk. So, there are very few reasons why government money should continue to be used for this technology.
1.1.5 The Century of Fossil Energy
Whereas traditional renewable energies covered most of the energy needs of mankind until the end of the nineteenth century, the twentieth century can be seen as the century of fossil energy. By the middle of the century fossil fuels in internal combustion engines had almost completely replaced the classic renewable energy systems, such as windmills, water wheels, and vehicles and machines driven by muscle power. Modern hydropower for the generation of electricity and biomass, which was mainly used as fuel, were the only renewable energies of any significance.
After the Second World War the demand for energy soared, and fossil energy sources were able to increase their share substantially. In 2016 fossil energies covered around 79% of the world's primary energy needs (see box p. and Figure 1.5). Hydropower and nuclear energy had a share of around 6% and 4%, respectively, and biomass around 9%. The other renewable energies amounted to just under 3%. Meanwhile, the situation has started to change. Solar and wind power have continuously high growth rates for new capacity, so their contribution to meeting global energy demand will increase significantly in the coming years. There was a slight decline in the use of coal in 2015 and 2016, while the demand for oil and gas is currently still increasing. If this trend continues, renewable energies could stop the growth in fossil fuels in just a few years and thus initiate effective climate protection measures.
Figure 1.5 Development of primary energy demand worldwide.
1.1.6 The Renewables Century
Although the share of renewable energies is still comparatively low at present, and the consumption of fossil fuels continues to rise despite all climate protection commitments, the twenty-first century is already on its way to becoming the century of renewables. Many cannot yet imagine a rapid change. Renewable energies share this fate with a multitude of new technologies. Emperor Friedrich Wilhelm II, for example, is said to have initially doubted the change in the transport sector: ‘I believe in the horse. The automobile is a temporary phenomenon’.
The internet and mobile phones have shown us how quickly new technologies can become established. Wind power and photovoltaics are currently expanding rapidly, with growth rates reminiscent of the introduction of the internet and mobile communications. Germany has long been a pioneer in the use of renewable energies. The millionth solar plant was opened there as early as 2011 (Figure 1.6). However, since 2013, when the German government significantly restricted the expansion of renewable energies, other countries, for example China, have taken over Germany's lead role in the expansion of renewable energies. Yet there is no doubt: The age of renewable energies has already begun worldwide. Soon they will break the dominance of fossil energies. The only question remains whether the replacement will come in time to stop climate change, which is progressing at an ever-faster pace. Nevertheless, the chances of this happening may be better than many currently dare to hope.
Figure 1.6 Left: Despite the intensive use of fossil fuels, the expansion of wind energy is booming in the USA. Right: The one-millionth PV installation in Germany. Source: Photos: Dennis Schwartz/REpower Systems SE and BSW-Solar.
1.2 Energy Needs – Who Needs What, Where, and How Much?
Demand for energy is distributed unevenly across the world. Six countries, namely China, the USA, Russia, India, Japan, and Germany, use more than half the available energy.
The USA alone needs one-sixth of the energy used in the world, even though less than one-twentieth of the worldwide population lives there. If every citizen of India were to use as much energy as the average American, global demand for energy would rise by about 60%. If all the people on Earth developed the same hunger for energy as the USA, demand would increase threefold (Figure 1.7).
Figure 1.7 Primary energy usage per head related to the world average.
Energy Cannot be Consumed, Actually
Anyone who has taken physics at high school will have learned about the concept of energy conservation. According to this principle, energy cannot be consumed or produced, but only converted from one form into another.
The car is a good example. The fact that cars consume too much is something we are keenly aware of each time we fill up with petrol. The petrol that a car needs, and we wince every time we pay for it, is a type of stored chemical energy. Combustion produces thermal energy. This is converted by an engine into kinetic energy and transferred to the car. Once all the petrol has been consumed, the car stops running. However, this does not mean that the energy has disappeared. Instead, it has been dispersed into the environment in the form of waste heat from the engine and heat generated as a result of air resistance and tyre friction. However, this ambient heat is no longer available for practical use; we are unable to produce petrol from ambient heat. When a car is driven, the usable energy content of the petrol is changed into an ambient heat that is no longer usable. This means that this energy is lost to us and thus consumed, even if this is not correct in terms of the laws of physics.
A photovoltaic system is a different matter. It converts sunlight directly into electric energy. It's often said that a solar system produces energy. From the point of view of physics, this is also incorrect. A solar system merely converts hard-to-use solar radiation into high-quality electricity.
When discussing which countries consume the highest amounts of energy, it is important to look beyond overall consumption figures. Population numbers also play an important role in any comparison. In absolute terms, India consumes more energy than Germany or the UK. But this is to be expected with a population of more than one billion people. Consumption per head in India is less than one-sixth of that in Germany or the UK. Although India is the country with the fourth highest use of primary energy in the world, its consumption per head is less than half the world average.
Figure 1.7 shows global primary energy needs per head of population. It is evident that the Western industrialized states and countries with large supplies of crude oil have a high rate of consumption because prosperity and cheap energy prices boost consumption. When it comes to the geographical pattern of consumption, the map clearly shows that the countries with very high consumption – with the exception of Australia, New Zealand, and South Africa – are all in the Northern hemisphere. Germany, France, the UK, and Italy together consume more than the entire African continent with its population of more than one billion.
Primary Energy, Apple Energy, and Orange Energy
If we compare our own electricity and gas consumption, we see that our consumption will almost always be higher if we heat our homes with gas. A comparison of the gas and electricity bills will not show much of a difference, though. Electricity and natural gas are two types of energy or energy sources that, like apples and oranges, cannot be compared directly like-for-like. Two to three kilowatt hours of gas have to be burnt in a power plant in order to produce 1 kWh of electricity from gas. The rest usually disperses unused into the environment as heat. When comparing different forms of energy, a distinction is therefore made between primary energy, final/secondary energy, and useful energy.
Primary energy is energy in its natural and technically unconverted form, such as coal, crude oil, natural gas, uranium, sunlight, wind, wood, and cow dung (biomass).
Final energy or secondary energy is energy in the form in which it is channelled to users. This includes natural gas, petrol, heating oil, electricity, and district heating (the use of a centralized boiler installation to provide heat for several buildings).
Useful energy is energy in its eventual form, such as light for illumination, warmth for heating and power for machines and vehicles.
The different forms of energy are most frequently compared on a primary energy basis. More than 90% of the original energy content is lost during the conversion of primary energy to usable energy. The classification of renewable energies is not always fully consistent. According to the definition, electricity from solar or wind power plants would be a final energy. However, many statistics refer to it as primary electricity and regard it as primary energy. We can only speculate about the reasons. On the one hand, the statistical identification of the ‘real’ primary energy relating to renewable electricity is difficult; on the other hand, the renewables resource is so large that efficiencies in the conversion from primary to final energy become less significant. Analogous to electricity from renewable power plants, hydrogen produced from renewable sources is also rated as primary energy in many statistics, although this is also a type of final energy in the narrower sense.
Countries with especially high energy consumption mostly use fossil energy sources to satisfy their energy needs. However, there are exceptions such as Iceland, where geothermal energy and hydropower dominate. On the other hand, countries with particularly low energy needs rely to a large degree on traditional biomass. This includes firewood and other conventional animal or plant products, such as dried animal dung. More than two billion people worldwide use firewood and charcoal for cooking and heating. In sub-Saharan Africa about 90% of the population is totally dependent on fuels from traditional biomass.
Big differences, however, also exist between the industrialized countries. Whereas many of them, such as Germany and the USA, use fossil fuels or nuclear energy to cover more than 80% of their primary energy demand, certain other industrialized countries have already increased their share of renewable energy use considerably. The Alpine countries, Norway, and Sweden use a noticeably high proportion of hydropower. Biomass also plays a big role in some countries like Sweden and Finland. In Iceland the natural heat of the earth is the energy form with the highest share. Hydropower and geothermal energy together cover well over 80% of Iceland's energy demand.
Ethiopia, on the other hand, is a typical example of one of the poorest countries in the world. More than 90% of the energy it uses is still based on traditional biomass. Figure 1.8 shows the difference in how four countries use key forms of energy to cover their energy needs.
Figure 1.8 Percentage of different energy sources covering primary energy demand in the DR Congo (2015), Germany (2016), Iceland (2015), and the USA (2016).
1.3 ‘Anyway’ Energy
According to statistics, only around 1.4% of Germany's primary energy consumption came from solar energy in 2016. In the UK and the USA, the percentage is even lower. The proportion of other renewable energies is also still quite low, making it difficult for most of us to imagine that renewable energies will be riding to the rescue of the environment in a few years. In reality however, renewable energies already constitute over 99% of German energy resources if one looks at the complete picture of energy use.
Winston Churchill supposedly said: ‘The only statistics you can trust are the ones you have falsified yourself’. It is widely believed that fossil fuel sources cover the lion's share of our energy needs. At least this is what all the usual statistics on energy claim. But it is only true if we define our energy demand in a very narrow way.
The heat of a radiator, the light provided by a conventional light bulb, and the driving energy of a ship's diesel engine generally form an integral part of our energy demand. What is not included in any statistics on energy is the warming effect of the sunshine streaming through windows, the sunlight that illuminates houses and streets so that artificial lighting can be switched off during daylight, and the wind that can propel sailing boats right across the Atlantic. A heated greenhouse that uses artificial light to grow useful plants is included in the statistics on energy; on the other hand, a covered early planting of vegetables that uses only natural sunlight is not included. The floodlight illumination of a stadium during an evening football game falls under our energy needs. If the football game takes place in the bright sunlight, the statistics on energy will claim that the football arena that is brightly lit up by the sun actually does not need any light. If we switch on snow blowers to compensate for the ever-decreasing amount of snow available in ski areas, this becomes a case for the statistics, whereas natural snow is not. When we fill our drinking water storage containers using electric pumps, we have to pay for the energy used. If rain fills the storage containers, this is not considered in the statistics. The high amount of electricity needed to run electric dryers also increases energy use. On the other hand, if the washing is dried by the wind and the sun on a conventional clothesline, this does not constitute an energy need as far as the statistics are concerned.
Natural and technically unconverted forms of energy are not a component in our energy demand in a conventional sense. Yet it should not make any difference where we derive the energy needed to heat our bath water, grow our plants, or provide light. We take the availability of natural renewable energy forms such as solar energy so much for granted simply because they are there anyway and thus, appear to have so little value that they do not even merit a mention in the statistics. However, this distorts our impression of our energy demand and puts the possibilities of renewable energy in a false light.
This can be illustrated using the example of energy consumption in Germany. Germany covers an area of 357 093 km2 and the annual solar radiation is on average 1064 kWh m‑2. Germany therefore benefits from 380 trillion kilowatt hours of energy from the sun each year. This is about 100 times as much as the primary energy consumption recorded in the statistics for Germany, and even more than the entire primary energy needs of the world. Part of this radiation heats the earth and the air; another part is converted into plant growth, thus producing biomass.
Around 800 mm or 0.8 m3 of rain fall per square metre in Germany. The annual rainfall for all of Germany adds up to 286 billion cubic metres. The sun evaporates this water before it reaches the Earth in the form of rain. One cubic metre of water requires 627 kWh to evaporate. This means the annual rainfall contains around 170 trillion kilowatt hours of energy.
About 2% of solar energy is converted through the movement of the wind. In Germany this amounts to around eight trillion kilowatt hours. Sun, wind, and water together produce abound 567 trillion kilowatt hours of energy in Germany each year. Geothermal and ocean energy are not even included in these figures. If this quantity of energy were to drop by a small percentage, the result would be drought and arctic winters (Figure 1.8).
The statistics of 2016 listed Germany's primary energy demand as being around 13 petajoules. This converts to close to just under four trillion kilowatt hours. Of course, the statistic includes solar energy, hydropower, and wind energy. The proportion of all renewable energies combined in the primary energy demand totals 0.5 trillion kilowatt hours. This is the amount that technical installations convert into renewable energy. The natural forms of renewable energy that exist anyway are totally omitted from this statistic. This explains the small obvious statistical discrepancy for the previous calculation of 567 trillion kilowatt hours for renewable energy resources. The difference between this and conventional statistics is clarified in Figure 1.9, where the natural renewable forms of energy that previously were not recorded in the statistics are referred to as ‘anyway’ energy – in other words, energy that exists anyway.
Figure 1.9 Total energy resources in Germany taking into account ‘anyway’ energy; that is, natural renewable forms of energy.
Anyone who thinks that these calculations amount to statistical hair-splitting is wrong. As the facts about climate change have now become public knowledge, there is a general interest in replacing fossil fuels with renewable energies as quickly as possible. But many people are under the impression that this is difficult to implement and almost impossible to accomplish within a reasonable period of time. The claim that solar energy only constitutes an insignificant share of energy resources is repeated like a prayer wheel. If this claim were true, this scepticism would be justified. In fact, it is fossil and nuclear energies that make up 0.6% of the energy resources in Germany. And no one could seriously doubt that 0.6% is replaceable in the foreseeable future.
The eruption of the Tambora volcano in Indonesia in 1815 shows us what happens when even a fraction of ‘anyway energy’ is lost. The gigantic quantities of volcanic gases and dust that were emitted into the atmosphere reduced the amount of sunlight available in the following years. In 1816 and 1817 Europe experienced massive crop failures. Ten thousand people died of starvation. If something like this happened today, we would suffer similar consequences. A large proportion of the energy that safeguards our food supply comes from a natural source – the sun. The small and diminishing supply of fossil and nuclear energy could not come anywhere close to compensating for even relatively minor fluctuations in natural energy.
The question then is what is ‘anyway energy’ worth? In Europe in 2017 oil cost more around 3 cents (euro) per kilowatt hour before tax; natural gas was around 1.7 cents, and rising. Because solar radiation and wind power cannot be stored as easily as oil and natural gas, their value is assumed to be less than that of natural gas, say 1 cent per kilowatt hour. Hydropower, on the other hand, could be set at 1.5 cents per kilowatt hour because it is easier to store. The total value of ‘anyway energy’ works out as around 6.5 trillion euros per year. According to this calculation, ‘anyway solar energy’ alone is worth around 3.8 trillion euros. In the USA, it is worth the equivalent of 100 trillion euros.
Natural renewable forms of energy in the order of 567 trillion kilowatt hours are not recorded as a separate entry in statistical calculations in Germany. This means that the public perception of the energy supply is distorted. We are left with the false impression that fossil and nuclear energy sources make up the major portion of our energy supply. In reality, the share from these sources is less than 1% and we should be replacing this with renewable energies as soon as possible to protect the climate. Natural renewable forms of energy to the value of around 6.5 trillion euros per annum are available to us today free of charge. We cannot afford to ignore this option.
1.4 Energy Reserves – Wealth for a Time
When we use fossil energy sources today, we are utilizing solar energy that was stored millions of years ago – but without the possibility of renewing this source in the foreseeable future. Yet our current hunger for energy is so great that most of the known fossil deposits will be used up during the twenty-first century. Also, suitable deposits of uranium fuel for conventional nuclear plants are becoming rarer.
Conventional or Non-Conventional, that is the Question
No two oil fields on Earth are alike. Some oil deposits are stored in liquid form only at a depth of 100 m below the ground. Others lie at a depth of 10 000 m or are mixed with sand and can only be mined at very high costs, if at all. In order to obtain a better overview of possible ranges, a distinction is therefore made between reserves and resources as well as conventional and unconventional deposits when indicating remaining reserves of crude oil, natural gas, coal, and uranium.
Reserves are proven energy feedstocks that can be economically extracted with today's technology at current prices.
Resources are proven but currently technically and/or economically not recoverable and not proven but presumed, i.e. purely speculative quantities of energy feedstocks. Only a fraction of the resources will therefore be accessible. If technology develops further or raw material prices rise, some resources are gradually added to reserves. Reserves then increase and resources decrease.
Total potential is the sum of reserves and resources. As things stand today, it will not be possible to fully exploit this potential. However, it is possible that new, unexpected deposits may still be found, thus increasing reserves or resources and thus the total potential.
Conventional deposits are reserves or resources that can be developed with conventional production methods. These include crude oil or natural gas in underground cavities that can be extracted via a simple well.
Non-conventional deposits are reserves or resources that are accessible with complex and innovative extraction methods. These include oil sands, oil shale, bitumen or crude oil, and natural gas in smaller cavities in impermeable layers, which first have to be broken up using a so-called fracking process. The extraction of unconventional deposits is often significantly more expensive than conventional ones.
For decades pessimists have been warning about the imminent end to fossil energy reserves. Yet, this end never quite seems to be in sight, and most people take no heed of the warnings. It was not until oil prices started to rise again in 2000 that the message that ‘black gold’ would one day run out finally sank home.
But the number of new finds, specifically of oil, has declined substantially during recent years, and new supplies cannot be exploited fast enough to meet rising demand. In the long term, oil prices will therefore continue to rise, even if brief dips in prices seem to signal an easing of the situation. On one hand, demand is rising, whereas supplies tend to be dwindling; and on the other hand, the effort needed to exploit new supplies is increasing along with the costs.
During the first commercial drilling in America in 1859, oil could be found at depths of 20 m, whereas today drilling at depths of up to 10 000 m is quite common. Significant technical progress has also been made in locating possible deposits, and so we know far more today about possible finds than we did several decades ago. However, this also makes it highly unlikely that any major new finds will be discovered.
1.4.1 Non-Conventional Reserves – Prolongation of the Oil Age
The strong increase in oil and gas prices since the 1990s has led to interest in developing completely new deposits that are mined using unconventional methods. A veritable new oil and gas fever has broken out in North America. In just a few years' time, the continent on the other side of the Atlantic could even briefly overtake the Middle East in oil and gas production.
In Venezuela, and in the Canadian province of Alberta, enormous quantities of oil sands have been found. These are retrieved in opencast mines. The Canadian mining region covers a gigantic area of 149 000 km2. This corresponds to approximately the size of England. The clearing of forests alone releases enormous volumes of carbon dioxide. The oil is then separated from the sand using large amounts of water and energy. What remains is heavily polluted wastewater and a devastated landscape. Due to the high energy consumption in oil sands production, carbon dioxide emissions continue to increase. Taking into account the release of greenhouse gases from deforestation, Canada's greenhouse gas emissions rose by an ‘impressive’ 46% between 1990 and 2010. The end of the oil age is already beginning to leave its dirtiest traces.
In the USA, the era of oil production was already largely over. Most of the exploitable conventional deposits have been exploited. New deposits in Alaska or the deep sea could only be developed to a very limited extent due to the enormous risks for the local environment. The strong military commitment of the USA in the Middle East in recent years has been due in no small measure to securing access to the energy feedstocks there.
But now a new technology has revolutionized the extraction of crude oil and natural gas in the USA: so-called fracking. First, a deep bore opens up the bedrock. Then a liquid is pressed into the well at high pressure, which causes cracks in the rock at depth. The idea is that gas or oil trapped in the rock will escape through these cracks and reach the surface via the borehole. If pure water were used for the process, the cracks would close immediately when the water is pumped back. This is why the water is mixed with sand and numerous chemicals, some of which are very toxic. This is intended to keep the cracks open, facilitate the outflow of oil or gas and prevent the growth of bacteria.
Environmentalists criticize numerous incalculable risks associated with fracking (Figure 1.10). Blasting the cracks in the ground can cause small earthquakes. Fracking chemicals can be released into the environment if handled improperly. The disposal of the large quantities of contaminated wastewater that is pumped back is problematic, and chemicals or natural gas can contaminate the groundwater and thus ultimately the drinking water via cracks and gaps. In the USA, drinking water has already been so polluted in various places, thus allowing this water to be ignited by the flammable methane dissolved in it. If natural gas escapes unused into the atmosphere, it also increases the greenhouse effect. The question remains whether a fairly short extension of the oil and gas age justifies such environmental impacts.
Figure 1.10 Operating principle and risks of natural gas fracking.
1.4.2 An End in Sight
In the past, constant technological advances in the exploitation of oil and natural gas have always resulted in a revision of the forecasts about the lifetimes of reserves. The large coal reserves still available worldwide in particular, could enable us to use fossil energy sources for decades or even another century.
At the current rate of production, the known supplies in the USA, Europe, and Asia will soon be depleted. This increases the dependency, particularly of the industrialized nations, on a small number of producing countries. The USA is trying to reduce this dependence by exploiting unconventional deposits. China is securing more and more access to deposits in other regions such as Africa. More than 60% of extractable oil supplies are found in the Middle East (Figure 1.11). The biggest oil producers in the region are Iraq, Iran, Kuwait, Saudi Arabia, and the United Arab Emirates.
Figure 1.11 Distribution of oil reserves on earth by region (2016). Source: BGR [BGR17].
This region has been the scene of major conflicts in recent years, and its large oil reserves are likely to increase tensions even further in the future. The dependency of the industrialized nations on the OPEC countries will also increase because these countries have almost three-quarters of the known reserves.
The current extent of availability can be calculated by dividing the known exploitable reserves by current production. In the case of oil, this is about 39 years (cf. Figure 1.12). The non-conventional reserves can extend the range by just 16 years. This range could drop further if there is an increase in annual production. In addition to the known reserves, new deposits are also being developed, which are currently still managed as a resource. It is estimated that the reserves will increase by between 50% and 100% due to these additional deposits. If production remains constant over the next few decades, the oil reserves will last another 100 years or so. However, in just the last 50 years, however, oil demand has almost tripled worldwide. Nevertheless, we can be pretty sure that oil will no longer be relevant as an energy source at the end of this century.
Figure 1.12 Range (in years) of known energy reserves and resources based on current production. Source: Data: BGR [BGR17].
The situation with natural gas and coal supplies is not quite so critical. Based on current production levels, the known gas reserves will be depleted in 52 years. In contrast to oil, the estimated additional resources are considerably more extensive than the reserves known to date. This is partly because the deposits are located at a lower depth than oil, and also because industrial production and the search for new supplies began much later. Over the last 50 years, however, the demand for natural gas has increased more than fivefold. Due to the continuing high level of consumption, natural gas supplies will also be running out during this century. Coal is the only fossil fuel that may still be available at the dawn of the next century.
1.4.3 The End of Fission
A key point about fuel supply, and one that most people are unaware of, is that even uranium supplies are very limited. Although there is more uranium in the Earth's crust than either gold or silver, less than 1% of the purest natural uranium can be used to create energy. Power plants can only use natural uranium after the usable part of uranium has been enriched with uranium U-235.
The share of ore must be higher than average to enable an effective exploitation of natural uranium. Canada is the only country that has deposits with a uranium ore content of more than 1%. If the uranium ore content drops, considerably larger amounts of it need to be mined for its degradation. This substantially increases the energy required to extract the ore and contributes to the costs.
Despite intensive efforts by some countries to develop nuclear energy, at 4%, its share of worldwide primary energy supply is still relatively low. A few countries like France are using nuclear power plants to cover up to 80% of their electricity demand. However, even in France cars cannot be run on nuclear power, and only some houses use nuclear energy for heating. Consequently, nuclear energy only really constitutes around 40% of the total primary energy supply, even in France.
The uranium deposits would be depleted in just a few years if nuclear energy were used to replace all fossil energies. Power plants could use other technologies, such as the risky fast breeder technology, to increase the amount of energy they are able to exploit, but this would do very little to change the fact that the supply of uranium is limited. The fact is that the uranium deposits that can be exploited economically will run out in a few decades at the most – which does not make a convincing argument for building new nuclear power plants with a lifespan of 30–40 years. For these reasons alone, nuclear energy is not a viable alternative to fossil energies.
1.5 High Energy Prices – the Key to Climate Protection
The low energy prices of the 1970s were the foundation not only of the economic miracle in several industrial countries, but of the massive rise in energy consumption. The founding of OPEC and the politically motivated limiting of production in 1973 led ultimately to a dramatic increase in oil prices. The industrialized countries were stunned and reacted with relative helplessness. In 1973 they founded the International Energy Agency (IEA) to coordinate their energy policies and ensure that the supply of energy remained secure and affordable.
The purpose of strategic oil reserves is to guarantee availability when the oil supply is interrupted and to stabilize prices. For example, Germany stockpiles 25 million tons of crude oil or crude oil products that can cover the country's oil demand for around 90 days.
The US strategic petroleum reserve is the largest in the world and holds up to 99 million tons. The commitment to developing the use of renewable energies also increased in the 1970s. However, a large number of failed mammoth projects showed that cost-effective and sustainable energy supply is not something that can be forced through; it can only be the outcome of long-term, ongoing development. Nevertheless, the oil crisis in the 1970s paved the way for the current boom in renewable energies.
The 1990s were marked by extremely low oil prices. As a result, efforts to save energy and to develop renewable energies stagnated. Due to booming global economic activity and extremely high demand, especially from China, oil prices reached new heights after the year 2000. The lack of commitment to reduce oil consumption took its revenge. Oil prices in 2012 were almost double what they were at the time of the oil crises in the 1970s (cf. Figure 1.13). Up to now this has only had a limited effect on the world economy. This can be explained by considering the inflation-adjusted oil prices. In 1980 one US dollar bought around three times as much as it could buy in 2017. The inflation-adjusted oil price at the time was therefore three times as high. Another reason is that the economy today depends considerably less on energy prices than at the time of the oil crisis. However, increasing oil prices would have significant impact on the world economy.
Figure 1.13 Development of oil prices with current prices and inflation-adjusted prices.
As the supplies of fossil energies begin to run out, oil, natural gas, and coal prices will rise further. The dip in prices since 2015 due to an international price war offers a short breather at best. Another round of price increases is a certainty. Political risks and a growing reliance on certain countries rich in raw materials also conceal the considerable possibility of another sudden hike in prices. For economic reasons it is important that some urgency be given to developing an alternative energy supply beyond fossil or nuclear energy sources.
During the period of transition, supply, and demand will also allow a fluctuation in the price of renewable energies, as was shown by the price increase for wood-burning fuels in 2006. However, in the long term the prices for renewable energies will continue to drop as a result of ongoing technical advances and more efficient production, whereas the price of fossil energy sources and nuclear energy will continue to rise.
Renewable energies are already fully competitive with fossil alternatives in many areas. In 2017, solar plants were already able to undercut prices of 2 cents per kWh−1 in tenders in the sunny regions of the world and are thus well below those of new fossil-fuel power plants. Even in less sunny Germany, solar plants can now undercut new fossil-fuel power plants, as there is practically no difference in the price of electricity from new solar and wind power plants at the current stock exchange electricity price.
However, the fossil age is massively supported by subsidies. Worldwide, the unimaginable sum of USD5.3 trillion was spent on subsidies for oil, gas, and coal in 2015. Without this support, the fossil age would soon be over for economic reasons alone. However, further increases in energy prices will sooner or later make this subsidy insanely unaffordable and thus initiate a rapid change towards a sustainable energy supply. Countries that started the transformation process early on will find it easier to master the challenges of the transition.