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The value of resource reserves and changes in reserves were estimated for the period 1958–91 for major mineral resources using the four valuation methods just discussed./11/ The minerals valued include the fuels (petroleum, natural gas, coal, and uranium), the metals (iron ore, copper, lead, zinc, gold, silver, and molybdenum), and other minerals (phosphate rock, sulfur, boron, diatomite, gypsum, and potash). Petroleum and gas account for the lion's share of mineral production. The other minerals were selected because, of the minerals that have scarcity value, their value of production was relatively high.
The picture that emerges from the various estimates of the value of U.S. mineral stocks is broadly similar, regardless of which methodology is used:
The stock of proved reserves increased from $103-$182 billion in 1958 to $471-$916 billion in 1991. In constant dollars, the stock rose somewhat and then fell, but over the period showed little change: From $544-$1,077 billion in 1958, the real stock slipped only slightly to $530-$1,030 billion in 1991. The patterns vary by type of mineral and reflect the effects of prices and costs of production, the volatility in international minerals prices, increasing environmental regulation, and the effect of strikes and other factors specific to each industry.
For petroleum, despite periodic concerns that the United States was running out of oil, additions have offset depletion throughout the period as oil companies have responded to higher net returns by stepping up exploration and improved recovery techniques to produce stocks of proved reserves sufficient to meet current and intermediate-term needs in light of current prices, costs, and interest rates. The one spike in the constant-dollar oil and gas series was in 1970, the year of the Alaskan oil strike.
For coal, additions have exceeded depletions, resulting in a generally rising constant-dollar value of stocks over time. For other minerals, the stock patterns have varied, with declining stocks in metals reflecting large declines in the returns to metals.
The 1991 stock of mineral reserves would add 3–7 percent to the 1991 value of reproducible tangible wealth of $13,637 billion, of which private nonresidential structures and equipment were $5,440 billion. Over time, the mineral reserves share of an expanded estimate of national wealth has fallen; in 1958, mineral reserves would have added 9–17 percent to reproducible tangible wealth. This decline appears to reflect several factors, including the economy's increased reliance on foreign resources and the increased efficiency in the use of fuels and other minerals.
Although industry makes large investments in exploring and developing mineral resources, the value of the invested capital associated with oilfields and mines is small relative to the value of the mineral reserves themselves. In 1991, the value of subsoil assets was 2–4 times as large as the associated capital invested in mining. Addition of these stocks of productive natural assets provides a more comprehensive picture of both the assets and the returns in the mineral industries.
Treatment of natural resources symmetrically with investments in equipment and structures provides a very different picture of rates of return to mining. Rates of return in the mineral industries calculated using income and capital stock as measured in the existing accounts—specifically, by dividing property-type income by the replacement value of structures, equipment, and inventories—averaged 23.1 percent for 1958–91. The more complete IEESA estimate deducts depletion and adds additions to property-type income, and it adds the value of resource stocks to the value of structures, equipment, and inventories. Depending on the valuation method used, the IEESA rate of return would be 3.5–5.2 percent. The effects of including mining resources are so large that the rate of return to all private capital is reduced from 16.1 percent to 14.1–14.9 percent. These IEESA rates of return provide a significantly different picture of the social rate of return to investments in the mining industries and the sustainability of the industries' output./12/
As noted, the highest estimates of resource reserves are from the current rent method based on the value of capital stock invested in the industry./13/ The value of subsoil assets using this method was $916 billion in 1991. The lowest value in 1991, $471 billion, was obtained from the current rent method based on a normal return to invested capital. The present discounted value estimates fell somewhere in between—$638-$812 billion.
The replacement-cost and transactions-price estimates were computed only for oil and gas. The transactions-price estimates, despite considerable smoothing, were quite volatile and erratic. The replacement-cost estimates produced the lowest values among all the estimates for gas. The transactions-price estimates produced the lowest values for oil.
For some of the subsoil asset estimates, especially those employing the current rent method based on a normal return to invested capital, the resource stock values and stock changes are quite low. In certain industries, especially the metals industries, the estimates were negative (indicated with an asterisk in the tables). These negative values indicate that the gross rents in these industries are so low that any procedure that assumes a normal return to capital in that industry must attribute a negative residual rent to the resource if total factor returns are to add up to market output. One can imagine an alternative procedure that assumes a normal return plus a depletion allowance and derives a negative residual for the invested capital associated with the resource.
http://www.ngpedia.ru/id404035p1.html
Big Encyclopedia of Oil and Gas, 2013
Wind turbine
Wind turbines are performed mainly with a horizontal axis of rotation.
The efficiency of the wind turbine depending on the wind velocity and the length of its blades. The quantity of energy produced is proportional to the cube of the wind speed and the square of the length of the blades. These dependencies caused economic profitability of constructing large wind turbines, which are designed to operate at high altitudes. Dependence on the height of the wind speed usually is logarithmic. Operating range of wind speeds large wind turbines from 5 to 15 m / s. When the wind speed is less than 5 m / sec the efficiency of the plant decreases. At wind speeds greater than 15 m / s is likely structural failure, especially blades. Distribution of the generators at high altitudes (where more speed) puts high demands on the structural strength of high masts, which should provide a strong hold to wind load of the rotor, gearbox and generator.
The energy output from a wind turbine depends on three factors: it is proportional to the wind speed to the third power, the rotor diameter (with the square) and the time during which the wind blows. Unfortunately, the places most favorable for wind energy, often have a beautiful natural landscape, or are far away from human settlements. The second of the factors listed above shows a very economical use of large wind machines, but their use may have some environmental impacts, such as wind turbine power 0 1 MW may cause distortion of television signals at a distance of 0 to 5 km. In 1977, it was assumed that by 1990 Canada will be set from 1 to 3 thousand wind turbines, each of which will produce 400 - 600 MW - hours per year.
In addition, bottom - Nurney workmanship vysokoskoros tion, variable speed and MOI tion turbines, shafts, regulators etc. still imperfect.
Thus, in Italy independent power producers on the basis of renewable energy received the right to sell its preferred price May 13 cents / (kWh), fixed for five years. In the U.S. Energy Policy Act in 1995, for every kilowatt - hour produced by wind turbines, relied subsidy January 5 cents.
The efficiency of the wind turbine depending on the wind velocity and the length of its blades. The quantity of energy produced is proportional to the cube of the wind speed and the square of the length of the blades. These dependencies caused economic profitability of constructing large wind turbines, which are designed to operate at high altitudes. Dependence on the height of the wind speed usually is logarithmic. Operating range of wind speeds large wind turbines from 5 to 15 m / s. When the wind speed is less than 5 m / sec the efficiency of the plant decreases. At wind speeds greater than 15 m / s is likely structural failure, especially blades. Distribution of the generators at high altitudes (where more speed) puts high demands on the structural strength of high masts, which should provide a strong hold to wind load of the rotor, gearbox and generator.
Inventory to determine possible areas of accommodation facilities and operate them. To compensate for the variability use a combination of settings such as including wind turbine and solar photovoltaics. Furthermore, wind power generators have a wide range of negative ecological effects, detected only after 70 - s. XX century.
Inventory to determine possible areas of accommodation facilities and operate them. To compensate for the variability use a combination of settings such as including wind turbine and solar photovoltaics. Furthermore, wind power generators have a wide range of negative ecological effects, detected only after 70 - s. XX century.
The experience of the development of wind power (Denmark, Germany, USA) shows that the state has a strong economic support for the direction of development of non-traditional energy sources. For example, appropriate independent producers legally guaranteed free access to the electric networks for the sale of electricity generated by wind turbines. Thus large energy companies are required to acquire this energy. For owners of wind turbines installed special reduced prices to ensure their increased profitability. Subject to partial subsidizing production costs for wind turbines. Preferential loans and interest-free loans for the purchase and installation of wind turbines.
Pages: 1
www.sworld.com.ua/simpoz3/7.pdf
IMPACT OF RENEWABLE ENERGY TO THE ENVIRONMENT
1.3. Solar Energy Power solar radiation absorbed by the atmosphere and the Earth's surface is 105 TWh (1017 W). This value seems huge compared to the current world power consumption of 10 TWh. Solar Energy - is the direction of renewable energy, based on the conversion of solar radiation to produce a thermal, mechanical and electrical energy. The basic methods of converting solar energy are primarily methods of direct use of solar energy - photovoltaic conversion and thermodynamic cycle. Photoelectric method of converting solar energy converter efficiency is up to 28%. In the process of producing electrical energy no mechanical moving parts installation structure. Photovoltaic systems require minimal maintenance, no need water and are well suited to remote and inaccessible areas. Efficiency of the photovoltaic module depends on three factors:
1. Orientation on the compass. Southern exposure is most preferred.
2. The angle of inclination. In the European part of Russia is the optimal angle range of 30 ° - 60 ° with a southern exposure.
3. Opacity. When installing photovoltaic cells need to be considered shade from nearby trees or buildings.
http://librarum.org/book/2838/516
Truhin VI, Pokazeev KV, VE Kunitsyn - General and environmental geophysics, 2005
Wind power
Mankind has been using wind energy. Sailing court - the main form of transport, which for centuries provided the link between people from different continents, are most striking example of the use of wind energy. Another well-known example of the effective use use of wind energy - windmills. First wind windmill appeared in Iran about 2000 years ago. They IME have a vertical axis of rotation. In Europe, windmills ppeared much later and had a horizontal axis of rotation. In Holland, windmills were widely used until recently for grinding grain and pumping water from polders (diked reduced land areas). In the middle of the XIX century. has been extended with a windmill a large number of blades. These windmills are widely multibladed used to supply water from wells. At the end of the XIX century, a new stage use wind turbines – they began to be used for power generation. In the 30- ies, XX century. wind power generators millions of eye - about 1 kW used in rural areas in Europe, America, Asia. In the Soviet Union in 1931, was built in the Crimea wind power station with a capacity of 100 kW, while she was the most powerful of the world. In 1956, the USSR produced nine thousands of wind turbines with capacity of 20 - 50 kW. However, as the central electric distribution - power supply, the emergence of economical and reliable diesel generator wind power generators spread plummeted. With the rising cost of fossil fuels and eco- awareness environmental impact of its application the hopes of many studies researchers again began to contact with wind energy. A phase of wind energy revival. Consider Following [ 31, 108, 146], its current state. Indeed, the wind potential is huge – about 2000 TWh of power of the wind flow in the atmosphere. Using even a small part of this power would to solve the energy problems of mankind. Practically, you can use no more than 10 % of these stocks. For the system systematization of wind characteristics drawn the so-called wind energy inventories.
http://ecology.my1.ru/index/0-92
Biomass, 2014
Biomass on land is very sensitive to rainfall, since water is involved in the biological cycle and serves as a source of hydrogen and oxygen to living matter.
Phytoplankton biomass and production of their organic matter varies in different regions of the ocean over a wide range, due to different levels of security elements organogens. Highest biomass observed in the coastal waters of the oceans and inland seas. For example, in the Azov Sea, it is an average of 2.4 g / m (0.3 to 9 g/m3) (Nesterov isoavt.
Biomass broadleaf forests close to the biomass of the southern taiga (,).
Biomass as a source of energy, used since ancient times. In the process of photosynthesis, solar energy is stored as chemical energy in the green mass of plants. Stored in biomass energy can be used as human or animal food or energy in the home and workplace. Currently 15 % of the energy in the world is produced from biomass. One ton of sawdust modern technology allows to obtain 700 kg of liquid fuel in Russia is 20 % of the forest resources of the planet.
Biomass, productivity, competition, population develops ecosystem on a lifeless surface. And what happens if the ecosystem is destroyed by fire.
If the biomass is present in the reactor in the form of biofilm or flo -cules speed cleaning process may be limited by diffusion. As a rule it is typical for reactors biofilters, but can also occur when using activated sludge. In both cases, there may be situations that can not be explained without considering the possibility of diffusion limitations of the reaction. To understand what is happening, not only the fact that diffusion limits the reaction rate, but also that the diffusion limitations lead to the formation of biomass in zones with different redox potentials. A good example is the simultaneous occurrence of the above-described in the aerobic biofilm removal of organic matter and denitrification. But this phenomenon has a more general nature.
As a result of the zooplankton biomass in the regulation period is a clear trend towards a significant reduction, which significantly complicates the ecological situation in the region.
www.muctr.ru/doc/tdism/4-kurs-ekologiya-prom-ekologiya-iii-2.doc
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