To obtain Pu for this purpose or for use in manufacturing nuclear weapons , spent fuel from nuclear generating stations is reprocessed.
Other trans-uranium elements and any remaining U as well as non-fissile U can also be recovered and be used to manufacture new fuel for reactors. So-called fast-breeder reactors are designed to optimize the production of Pu which occurs when an atom of U absorbs a neutron to produce U, which then forms Pu by the emission of two beta electrons.
Although fast-breeder reactors have been demonstrated, they have not been commercially developed. However, there are limits to the process because the original quantity of U is eventually depleted.
Therefore, both U and Pu should be considered to be non-renewable resources. A number of important environmental problems are associated with nuclear power. These include the small but real possibility of a catastrophic accident such as a meltdown of the reactor core, which can result in the release of large amounts of radioactive material into the environment as happened at the Chernobyl reactor in Ukraine in Nuclear reactions also produce extremely toxic, long-lived radioactive by-products such as plutonium , which must be safely managed for very long periods of time up to tens of thousands of years.
Fusion is another kind of energy-producing nuclear reaction. This process occurs when light nuclei are forced to combine under conditions of extremely high temperature millions of degrees and pressure, resulting in an enormous release of energy.
Fusion usually involves the combining of hydrogen isotopes. One common fusion reaction involves two protons two hydrogen nuclei, 1 H fusing to form a deuterium nucleus composed of one proton and one neutron, 2 H , while also emitting a beta electron and an extremely large amount of energy. Fusion reactions occur naturally in the interior of the Sun and other stars, and they can also be initiated by exposing hydrogen to the enormous heat and pressure generated by a fission nuclear explosion, as occurs in a so-called hydrogen bomb.
However, nuclear technologists have not yet designed a system that can control fusion reactions to the degree necessary to generate electricity in an economic system. If this technology is ever developed, it would be an enormous benefit to industrial society. It would mean that virtually unlimited supplies of hydrogen fuel for fusion reactors could be extracted from the oceans, which would essentially eliminate constraints on energy supply.
So far, however, controlled fusion reactions remain the stuff of science fiction. Hydroelectric energy involves harnessing the kinetic energy of flowing water to drive a turbine that generates electricity.
Because the energy of flowing water develops naturally through the hydrologic cycle, hydroelectricity is a renewable source of energy. There are two classes of technologies for the generation of hydroelectricity. All of these facilities have large reservoirs to store water.
Although hydroelectric energy is renewable, important environmental impacts are associated with use of this technology. Changes in the amount and timing of water flow in rivers cause important ecological damages, as does the extensive flooding that occurs when a reservoir is developed see Chapter Hydroelectricity is a renewable source of energy.
This facility taps part of the flow of the Niagara River to generate electricity. Solar energy is continuously available during the day, and it can be tapped in various ways as a renewable source of energy. For example, it is stored by plants as they grow, so that their biomass can be harvested and combusted to release its potential energy see Biomass Energy, below.
Solar energy can also be trapped within a glass-enclosed space. This happens because glass is transparent to visible wavelengths of sunlight, but not to most of the infrared. Solar energy can also be captured using black, highly absorptive surfaces to heat enclosed water or another fluid, which can then be distributed through piping to warm the interior of a building.
Solar energy can also be used to generate electricity using photovoltaic technology solar cells , which converts electromagnetic energy directly into electricity. In another technology, large, extremely reflective parabolic mirrors are used to focus sunlight onto an enclosed volume that contains water or another fluid, which becomes heated and generates steam that is used to drive a turbine to generate electricity.
Geothermal energy can be tapped in the very few places where magma occurs relatively close to the surface and heats ground water. The boiling-hot water can be piped to the surface, where its heat content is used to warm buildings or to generate electricity. In addition, the smaller energy content of slightly warmed geothermal water, which is present almost everywhere, can be accessed using heat-pump technology and used for space heating or to provide warm water for a manufacturing process. Geothermal energy is a renewable source as long as the supply of groundwater available to be heated within the ground is not depleted by excessive pumping.
The kinetic energy of moving air masses, or wind energy, can be tapped and used in various ways. A sailboat uses wind energy to move through the water, a windmill may be used to power the lifting of groundwater for use at the surface, and wind turbines are designed to generate electricity. Extensive wind-farms, consisting of arrays of highly efficient wind-driven turbines, have been constructed to generate electricity in consistently windy places in many parts of the world.
Wind is increasingly being used as a source of commercial energy in Canada. These wind turbines are operating near Tilbury in southwestern Ontario.
Tidal cycles develop because of the gravitational attraction between Earth and the Moon. In a few coastal places, tidal energy, the kinetic energy of tidal flows, can be harnessed to drive turbines and generate electricity. The Bay of Fundy in eastern Canada has enormous tides, which can exceed 16 m at the head of the bay. There is potential for much more tidal power development within the Bay of Fundy, and there are ongoing technological studies to install additional facilities at various places there.
The new installations will use tidal-powered turbines that are laid on the bottom or suspended in the water column, which avoids the environmental damage associated with a dam. Waves on the ocean surface are another manifestation of kinetic energy. Wave energy can be harnessed using specially designed buoys that generate electricity as they bob up and down, although this technology has not yet been developed on a commercial scale.
The biomass of trees and other plants contains chemical potential energy. This biomass energy is actually solar energy that has been fixed through photosynthesis. Peat, mined from bogs, is a kind of sub-fossil biomass. Like hydrocarbon fuels, biomass can be combusted to provide thermal energy for industrial purposes and to heat homes and larger buildings. Biomass can also be combusted in industrial-scale generating stations, usually to generate steam, which may be used to drive a turbine that generates electricity.
Biomass can also be used to manufacture methanol, which can be used as a liquid fuel in vehicles and for other purposes. If the ecosystems from which biomass is harvested are managed to allow post-harvest regeneration of the vegetation, this source of energy can be considered a renewable resource.
Peat, however, is always mined faster than the slow rate at which it accumulates in bogs and other wetlands, so it is not a renewable source of biomass energy. The consumption of energy varies greatly among countries, largely depending on differences in their population and degree of development and industrialization Table In general, the per-capita use of primary energy this refers to fuels that are commercially traded, including renewables used to generate electricity in less-developed countries is less than about 1 toe per person per year.
The use of traditional fuels is not reflected in the data of Table Countries that are developing rapidly are intermediate in their per-capita energy consumption, but their rates of energy use are increasing rapidly due to their industrialization.
While the use of energy has grown in these and other rapidly developing countries, their reliance on traditional fuels has dropped. This happens because traditional fuels are relatively bulky, smoky, and less convenient to use than electricity or fossil fuels, particularly in the urban environments where people are living in increasingly large numbers.
In addition, the supplies of wood, charcoal, and other traditional fuels have become severely depleted in most rapidly developing countries, particularly near urban areas. Relatively developed countries have a high per-capita consumption of energy Table Consumption of Primary Energy in Selected Countries in Primary energy refers to fuels that are commercially traded, including renewables used to generate electricity.
National energy consumption mostly reflects the size of the economy of a country and its population, while per-capita use allows for a comparison of the lifestyle-intensity of average people. Source: Data from BP In terms of the total amounts of energy being used, the largest consumers are China 2, toe in , the United States 2, , and Russia toe.
Canada is a highly developed country, but because of moderately-sized population and economy, it uses considerably less energy in total, about toe. The fact that per-capita energy use increased much less quickly than national consumption suggests that Canadians have become more efficient in their use of energy, especially during the more recent period.
Smaller automobiles, improved gas economy of vehicles, better insulation of residences and commercial buildings, and the use of more efficient industrial processes have all contributed to this increased efficiency. Nevertheless, although these gains of energy efficiency have been substantial, they have been more than offset by growth in the per-capita ownership of automobiles, consumer electronics, and other energy-demanding products and technologies.
Also important have been large increases in industrial energy use associated with oil-sands developments in Alberta during the past several decades. These latter changes have caused the overall use of energy in Canada to increase substantially. Trends in the Consumption of Primary Energy in Canada. Sources: Data from British Petroleum The intensive energy usage by Canadians reflects the high degree of industrialization of our national economy.
Also significant is the relative affluence of average Canadians compared to the global average. Wealth allows people to lead a relatively luxurious lifestyle, with ready access to energy-consuming amenities such as motor vehicles, home appliances, space heating, and air conditioning. Canada is also a large country, so there are relatively large expenditures of energy for travelling.
In addition, the cold winter climate means that people use a great deal of energy to keep warm. As was examined in Chapter 12, a sustainable enterprise cannot be supported primarily by the mining of non-renewable sources of energy or other resources. Therefore, a sustainable economy must be based on the use of renewable sources of energy. However, most energy production in industrialized countries is based on non-renewable sources.
Averaged across the relatively developed countries shown in Table With such a small reliance on non-renewable sources, it is clear that the major economies of the world are not close to having developed sustainable energy systems. Considering the rapid rate at which reserves of non-renewable energy resources are being depleted, one wonders how long the energy-intensive economies of developed nations can be maintained.
Energy Consumption in Selected Countries in Data are in units of tonnes of oil equivalent. There are also, of course, environmental impacts of the harvesting of trees and other kinds of biomass for use as fuel see Chapter Sources of Primary Energy in Canada. The data are for and are in units of tonnes of oil equivalent.
Electricity produced by public or private utilities accounts for much of the energy used by industry, institutions, and residences in Canada. Non-renewable resources are always diminished as they are used. Although non-renewables can be used with great enthusiasm to achieve economic growth, they cannot be the basis of a sustainable economy.
Only renewable resources can play that fundamental role. For instance, the life index of the global reserves of copper is only about 39 years, while that of nickel is 30 years, and zinc 19 years. Natural gas is widely used for cooking and for heating homes. Natural gas can be pumped out through the same wells used for extracting crude oil.
Coal is a solid fossil fuel that is used for heating homes and generating power plants. It is found in fossilized swamps that have been buried beneath layers of sediment. Since coal is solid, it cannot be extracted in the same manner as crude oil or natural gas; it must be dug up from the ground. Nuclear energy comes from radioactive elements, mainly uranium , which is extracted from mined ore and then refined into fuel.
Unfortunately, human society is—for the time being—dependent on nonrenewable resources as its primary source of energy. Approximately 80 percent of the total amount of energy used globally each year comes from fossil fuels. We depend on fossil fuels because they are energy-rich and relatively cheap to process. But a major problem with fossil fuels, aside from their being in limited supply, is that burning them releases carbon dioxide into the atmosphere.
Rising levels of heat-trapping carbon dioxide in the atmosphere is the main cause of global warming. Alternative energy sources, such as wind and solar energy, are a possible solution to the depletion of nonrenewable sources. Both of these clean energy sources are available in unlimited supply. Also called diesel oil and diesel fuel. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
The Rights Holder for media is the person or group credited. Minerals, used for making metals, are also nonrenewable natural resources. Nonrenewable natural resources are things that take longer than a person's lifespan to be replaced. In fact, they can take millions of years to form. Fossil fuels such as oil, coal, and gas will not last forever. They are nonrenewable.
People are trying hard to find new fuels that are clean and will provide the power we need. Wind, solar, and hydrogen power are renewable resources that offer hope for the future. People use both types of natural resources to produce the things they need or want. Our homes, clothing, plastics, and foods are all made from natural resources. Let's look at each one of these to be sure.
Your home is in a building. Buildings are made out of wood and minerals. Wood is from trees. Minerals are mined from the ground. Bricks, cement, and metals are made from minerals. How about your clothes?
Most of your clothing is made from cotton, polyester, or nylon. Cotton comes from cotton plants. Polyester and nylon are made from oil.
Plastics are made from oil too. How about your food? People eat grains, fruits, and other parts of plants. You may also enjoy dairy products and meat from animals. Everything we have or use is made from a natural resource. Which of those mentioned here are renewable? Which are nonrenewable? All natural resources should be used wisely. We must conserve natural resources. Conserve means to not use up, spoil, or waste things.
This is especially true for the nonrenewable resources. However, even some renewable natural resources can run out if they are all killed or overused. We must also protect our natural resources from pollution. Pollution occurs when people put harmful chemicals and other things into nature.
Oil spilled in water, toxic chemicals in the air, or garbage dumped on the side of the road are examples of this problem. You can reduce, reuse, and recycle! For example, turn off the lights when you are not in a room. This process releases greenhouse gases into the atmosphere, contributing to toxic air pollution and climate change. Gas and oil are nonrenewable energy fuels that also function as main energy resources. Petroleum is formed from the remains of ocean-dwelling phytoplankton that died approximately million years ago.
Natural gas is found as a component of petroleum, as well as in gaseous deposits separate from petroleum. Both of these energy sources release carbon dioxide into the atmosphere and natural gas also releases methane due to leaks in the process of extracting it. The extraction of oil fuel has caused major damage to marine ecosystems from oil rig malfunctions and spills in our oceans and from runoff caused by extraction on land. Steel and aluminum are metals that are extracted from the earth and are nonrenewable.
These resources are part of our daily lives, whether they make up our appliances or manufacturing equipment or enable the agricultural processes that feed our planet to work. Aluminum and iron ore, a main component of steel, are acquired from open-pit mining which is detrimental to the earth and ecosystems, resulting in pollutant-filled runoff and climate problems.
The extraction of rare earth metals is complicated as these elemental structures are connected with other minerals. Rare earth metals are an important nonrenewable resource that is an essential component in all our electronic and high-tech devices.
The extraction of these rare earth metals from the earth is harmful to our environment and our extreme dependence on them as nonrenewable resources is a cause for concern. It is time to start studying and exploring renewable solutions to create our high-tech gadgets. Phosphates, which come from the element phosphorus, are an extremely important resource in our daily lives. This resource is so important in conventional agriculture, much of farming and cultivating is actually dependent on phosphates in fertilizer to feed our plants and animals.
Phosphates are mined from minerals inside of the earth and refined and purified for its application in many widespread products.
However, continued massive extraction of this nonrenewable resource is not sustainable, as Julia Rosen notes in The Atlantic. Alas, there are renewable solutions that cause exponentially less harm to the environment and could enable a cleaner future.
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