panels capture solar energy or convert energy from sunlight. In all cases, the daily consumption and the generation of a solar system, it is energy, not "power."
watch the next page:
http://www.codeso.com/Calculo01A.html
Thursday, February 28, 2008
Fleas On Dogs Stomach
panels capture solar energy or convert energy from sunlight. In all cases, the daily consumption and the generation of a solar system, it is energy, not "power."
watch the next page:
http://www.codeso.com/Calculo01A.html
Tuesday, February 26, 2008
Racquel Darrian Raquel On Fire
solar battery solar electric
car accumulator. Called
battery, electric battery or just battery, the device that stores electrical energy using electrochemical methods and then returns almost entirely, this cycle can be repeated by a number of times. This is a secondary electric generator, ie a generator can not operate without electricity previously supplied him with what is called charging.
also often called battery as many times several of them are connected in series to increase the supply voltage. Thus, a car battery is made internally by 6 elements accumulator lead-acid type, each of which supplies electricity at a voltage of about 2 V, so that all the usual 12 V supply, or 12 items at 24 V for trucks.
The term battery in Castilian, called the non-rechargeable power generators. Both battery and battery are terms from the early days of electricity, in which several cells or cells - in the first case, one above another, "stacked", and the second, attached laterally, "on battery" , as is done today in order to increase the magnitude of electrical phenomena and to study them systematically. This explanation suggests that either serve to any names, but the custom has fixed the distinction. Contents
Operating Principles of Operation battery is based essentially on some sort of reversible process, ie a process whose components are not consumed or lost result, but merely transformed into another, which in turn can return to the state first in the right circumstances. These circumstances are, in the case of batteries, the closure of the external circuit during the discharge process and the implementation of a stream, just outside during the load.
turns out that such processes are quite common, oddly enough, in the relations between the chemicals and electricity during the process called electrolysis , and voltage generators or batteries . The nineteenth century researchers devoted many efforts to observe and investigate this phenomenon, which was named polarization.
An accumulator is thus a device that takes the polarization achievable limits, and generally consists of two electrodes the same or different material, immersed in an electrolyte . History
Alessandro Volta announced his invention of the stack to the Royal London Society, March 20 of 1800. Johann Wilhelm Ritter
built his electric battery 1803. Like many other that followed, was a theoretical and experimental prototype, with no possible practical application.
In 1860 , Gaston Plante developed the first model of lead-acid battery with pretensions to be a usable device, which was only very relatively, so it was not successful. In the late nineteenth century, however, the electricity was rapidly becoming everyday items, and when I planted again to publicly explain the features of your store, in 1879 , had a better reception, so it began to be manufactured and used almost immediately, beginning an intense and ongoing process of development to perfect it and ignore its deficiencies, a process that continues today.
Thomas Alva Edison invented in 1900 , another type of battery with electrodes of iron and nickel, whose electrolyte is potassium hydroxide (KOH). First commercialized in 1908 , and are the basis of current models alkaline rechargeable or not.
Also by 1900, in Sweden, Berg invented Junger and Ni-Cd battery, which uses cadmium anodes instead of iron, being very similar to that of ferronickel in other characteristics.
battery types
As their size and other characteristics external concerns, consult this list , since many of them are common to batteries and accumulators and are standardized.
As far as concerns their internal nature, are commonly found in trade accumulators of the following types:
lead accumulator is composed of two electrodes lead, so that when the device is downloaded , is in the form of lead sulfate (PbSO4 II) embedded in a matrix of metallic lead (Pb), the electrolyte is a solution of sulfuric acid . This type of battery is still used even in many applications, including in the car. Its operation is as follows:
During the initial charging, lead sulfate (II) is reduced to lead metal at the negative pole, while the anode forms lead oxide (IV) (Pb O2) . Therefore, it is a dismutation process . No hydrogen is released, since the reduction of protons to elemental hydrogen is kinetically hindered at a lead surface, a favorable characteristic is reinforced by including the small amounts of silver electrodes. Hydrogen evolution would cause slow degradation of the electrode, helping it crumble mechanically parts of it, irreversible changes that shorten the battery service life.
During discharge processes are reversed loading. Lead oxide (IV) is reduced to lead sulfate (II), while the elemental lead is oxidized to sulfate also give lead (II). Exploit the electrons exchanged in the form of electrical current through an external circuit. It is, therefore, of a switch. The term commences elementary processes are:
PbO2 + 2 H2SO4 + 2 e--> 2 H2O + SO42-
PbSO4 + Pb + SO42--> PbSO4 + 2 e-
low discharge in the concentration of sulfuric acid because it creates lead sulphate and increases the amount of water released in the reaction. As concentrated sulfuric acid has a density greater than the dilute sulfuric acid, the acid density can be an indicator for charging status of the device.
However, this process can be repeated indefinitely, because when the lead sulfate crystals form very large, and not respond well to the processes outlined, so you lose the essential characteristic of reversibility. We then say that the battery is sulfated and must be replaced by a new one.
The batteries of this type sold today use a paste electrolyte, which does not evaporate and does a lot more comfortable and safer to use.
Alkaline Battery
ferronickel also called, the electrodes are shaped steel plates with honeycomb mesh inserts nickel oxide (NiO), which form the positive electrode, and ferrous oxide (FeO), the negative, being formed the electrolyte solution of potassium hydroxide (KOH). During the load is an anodic oxidation process and a cathodic reduction , becoming the nickel oxide in nickel and ferrous oxide in metallic iron. This reaction occurs in reverse during unloading.
In 1866, George Leclanché invented in France the "stack dry "(Zinc-Manganese Dioxide) system that still dominates the world market for primary batteries. Alkaline batteries (for "high power" or "long life") are similar to those of Leclanché, but instead of ammonium chloride, lead chloride, sodium or potassium. They last longer because zinc is not exposed to an acidic environment such as ammonium ions that cause the conventional battery. As the ions move more easily through the electrolyte, produces more power and a more stable flow.
The higher cost stems from the difficulty of sealing the cell against leakage of hydroxide. Almost all are shielded, which prevents the shedding of constituents. However, this shield does not have unlimited time. Alkaline dry cells are similar to common dry cells, with the following exceptions:
the electrolyte is basic (alkaline), because it contains KOH
the inner surface of the container of Zn is rough, this provides a larger contact area.
Alkaline batteries have a longer shelf life than the common dry cells to better withstand constant use.
voltage alkaline battery is close to 1.5 v. During unloading, the reactions in the alkaline dry cell are:
Anode: Zn (S) + 2 OH-(aq) Zn (OH) 2 (s) +2 e-
Cathode: 2 MnO2 (S) + 2 H2 O (l) + 2 e- 2MnO (OH) (s) + 2 OH-(ac)
Global: Zn (s) +2 MnO2 (s) 2H2O (l) Zn (OH) 2 (aq) + 2MnO (OH) (s)
The anode is made of a paste of zinc amalgamated with mercury (total 1%), carbon or graphite.
devices are used for complex and energy intensive. In versions 1.5 volt, 6 volt and 12 volts are used, for example, remote controls (remote control) and alarms.
alkaline manganese batteries with mercury content of around 0.1% of its total weight is an enhanced version of the previous stack, which has replaced the chloride ion conductor ammonium hydroxide Potassium (hence the name of alkaline). The battery container is steel, and disposition of zinc and manganese oxide (IV) is the opposite, placing the zinc powder now in the middle. The amount of mercury used to regulate the discharge is higher. This gives more time, more constancy in time and better performance. By contrast, the price is higher. It also provides an electromotive force of 1.5 V. It is used in most consumer devices such as portable recorders, motorized toys, electronic flashes.
The amalgamated zinc anode is the cathode material is a polarizer that is based on manganese dioxide, mercuric oxide intimately mixed with graphite, and in rare cases Ag2O silver oxide (the latter two are of use expensive, hazardous and toxic), to reduce its electrical resistivity. The electrolyte is a solution of potassium hydroxide (KOH), which presents a very low internal resistance, allowing not to take internal discharges and energy can be stored for a long time. This electrolyte in the battery business is hardened gelatin or cellulose derivatives.
This type of battery is manufactured in two ways. In one, the anode consists of a corrugated zinc strip, spirally wound from 0.051 to 0.13 mm in thickness, which is Amalgam after assembly. Two strips absorbent paper interdevanadas alkali resistant paper strip with zinc, zinc so that it extends to the top and bottom paper. The anode is insulated from the metal box with a polystyrene sleeve. The top of the stack is made of copper and makes contact with the strip of zinc to form the negative terminal of the battery. The battery is sealed with a grommet or eyelet made of neoprene. The battery casing is chemically inert to the ingredients and form the positive electrode.
Alkaline Zinc 14% (anode) Toys, tape players, cameras, recorders
22% manganese dioxide (cathode)
Coal: 2%
Mercury 0.5 to 1% (anode)
potassium hydroxide (electrolyte)
42% plastic and sheet
contains an alkaline compound called potassium hydroxide. Its duration is six times greater than that of zinc-carbon. It is composed of manganese dioxide, potassium hydroxide, zinc paste amalgamated with Mercury (total 1%), carbon or graphite. According to the European Directive of March 18, 1991, these batteries can not exceed the amount of 0.025% mercury.
This type of battery has some cons:
An alkaline battery can contaminate 175,000 liters of water, which becomes the average water consumption of all the lives of six people.
An ordinary battery, also called zinc-carbon, can contaminate 3,000 liters of water.
nasal septum perforations.
Zinc, Manganese, Bismuth, Copper and Silver: These are toxic substances that produce various alterations in human health. Zinc, Manganese and Copper are essential for life, in minute amounts, toxic in high doses. Bismuth and Silver are not essential for life.
Nickel Hydride Batteries (Ni-H)
utilize a hydroxide anode and cathode nickel alloy metal-hydride batteries. Each cell of Ni-H can provide a voltage of 1.2 V and a capacity between 0.8 and 2.3 Ah. Its energy density reaches 80 Wh / kg. These batteries are affected by the so-called memory effect, which is limited in each charging voltage or the capacity (because of a long, high temperature or high current), precluding the use of all its energy.
Nickel-Cadmium Batteries (Ni-Cd)
They use a nickel hydroxide anode and cathode of a compound of cadmium . The electrolyte is potassium hydroxide . This configuration of materials can recharge the battery once it is exhausted, for reuse. Each NiCd cell can provide a voltage of 1.2 V and a capacity between 0.5 and 2.3 Ah. No However, its energy density is only 50 Wh / kg, which means they have to be recharged every so often. They are also affected by memory effect.
Lithium-Ion Battery (Li-ion) batteries
The Lithium-Ion (Li-ion) use a lithium anode and a cathode Ion. Its development is more recent, and can reach densities of around 115 Wh / kg. Also, do not suffer from memory effect .
Lithium Polymer Batteries (Li-Poly)
are a variation of Lithium-Ion Battery (Li-ion) . Its characteristics are very similar, but allow higher energy density and a significantly higher discharge rate.
Fuel Cells
The fuel cell is not an accumulator itself, although it converts chemical energy into electricity and is rechargeable. Works with hydrogen . (Other fuels such as methane or Methanol are processed prior to hydrogen).
high capacity condenser
Although high-capacity capacitors electrochemical batteries are not strictly speaking, are now getting enough capacity large (several farads, F) so that they can be used as a battery when the power supplied are small.
parameters of a battery voltage
The or potential (in volts ) is the first parameter to consider, as is what usually determines whether the accumulator should use to which it is intended. Is fixed by the reduction potential of redox couple used, generally between 1 V and 4 V per cell.
The current that can supply the item, as ampere (A), is the second factor. Is particularly important in some cases the maximum current obtainable; p. eg., starter motors for cars require brutal efforts of the battery when put into operation (tens of A), so you must act for a short time.
electrical capacity is measured in practice by reference to the time of loading and discharge in Ah. SI unit is the coulomb (C).
1 Ah = 1000 mAh = 3600 C, 1 C = 1 Ah/3600 = 0.278 mAh.
Note, however, that, when you get indications on the body of batteries or packs, as Please charge at C/10 for 12 hours the letter C does not refer to Coulomb, but maximum load may receive the battery, so that in the previous case, if they were battery capacity 1200 mAh, you should apply a charging current = 120 mA during 1200-1210 the number of hours indicated.
The stored energy is usually measured in Wh ( watt-hour), the SI unit is the joule (unit) .
1 Wh = 3600 J = 3.6 kJ 1 J = 0.278 mWh
The resistance of the batteries is much lower than that of the batteries, allowing them to supply loads more intense than the latter, especially as transient. For example, the internal resistance of a lead-acid battery is of 0.006 ohm , and other Ni-Cd, from 0.009 ohm.
Finally, another important feature of a battery is its mass, ie, weighing, and the relationship between it and the electrical capacity (Ah / kg) or energy (Wh / kg) that can restore. In some cases it may also occupy a significant volume (m3 or liters).
The yield is the percentage ratio between the power received in the process of loading and delivery to the battery during discharge. The lead-acid battery is rated at over 90%.
batteries as contaminants
As seen, the batteries contain heavy metals and chemicals, many of them harmful environment. It is very important not to throw them away (in most countries this is not allowed) and take them to a recycling center. Currently, most vendors and specialty shops are also in charge of the batteries.
In Mexico, the release of mercury in batteries has occurred as a result of using three types of batteries: the oxide of mercury, the C-Zn and alkaline. In the first type, the metal content is 33% and were used in presentation and in other button sizes, from 1955. Theoretically, it ceased production in 1995, although there are sources that indicate that this process continues in Asia and distributed in the international market. For the second and third types of batteries, it is known that for several decades before 1990, they added mercury (0.5 to 1.2%) for best performance, with the highest alkaline content, also containing coal is sometimes contaminated with this metal naturally. In 1999, the INE requested an analysis of samples from three different brands of AA batteries normally consumed in Mexico, of which two were of Asian origin (of C-Zn) and alkaline European origin. The results were as follows: for those of Asian origin, the values \u200b\u200bwere between 0.18 mg / kg and 6.42 mg / kg, in terms of European origin the result was 0.66 mg / kg, and these amounts, equivalent to parts per million, does not exceed the limits of 0.025% under the Protocol on heavy metals taken in 1998 in Aarhus, Denmark, by members of the Economic Commission for Europe (UNECE). The previous sample was an isolated incident and it would be in the future to further analyze the mercury content in the largest possible number of brands. According to calculations presented in Table 10, an estimated 1,232 tons have been released over the past 43 years. In Mexico, the other sources of mercury are industry chlorine / soda, which is used in the process, and also products such as thermometers, various types of switches and fluorescent lamps. According to official information and is not removed mercury in Mexico, although data on imports amounting to 130 tonnes in the last three years. Mercury is a local and global pollutant par excellence. Environmental chemistry for this toxic metal is very complex, given its properties, it evaporates at room temperature, the atoms travel far, to be deposited in bodies of water are transformed into organic mercury (methyl mercury) for aerobic and anaerobic mechanisms , this is how it becomes contaminated, among others, seafood. Another form of mercury poisoning is inhalation of vapors from the mercury in its metallic form indoors. Methyl mercury can cross the placenta, accumulate and cause damage to the brain and tissues of infants who are particularly sensitive to this substance. There may also be exposed to mercury through breast milk, in this case, the effects can cause developmental problems, delays in walking, speech or mental lack of coordination, blindness and seizures. In adults, chronic exposure through ingestion of contaminated food, usually fish, can cause personality changes, loss of vision, memory or coordination, deafness, or problems in the kidneys and lungs. The International Agency for Research on Cancer (IARC, for its acronym in English) of the World Health Organization (WHO) considers to methyl mercury and its compounds as possibly carcinogenic to humans (Group 2B). Methyl mercury, which is the most toxic, accumulates in fish tissue, the larger specimens and older tend to concentrate higher levels of mercury.
Manganese: As the most used battery types are alkaline and C-Zn (approximately 76% of total batteries), the oxide manganese content in them is the pollutant that increased volume has been released into the environment over the past four decades, which is about 145.917 tons (Table 10). Regarding adverse effects on human health caused by this substance, several studies suggest serious neurological effects from oral exposure to manganese. For example, a study by the WHO reports that in 1981 poisoning was reported in a community in Japan, due to near a water well were buried around 400 pieces of batteries at a distance of approximately two meters, causing 16 cases of poisoning, three were fatal (including suicide). Manganese levels detected in water from that well was 14 milligrams per liter, while in other two wells reached levels 8 and 11 milligrams per liter. Community subjects exhibited disorders of psychological and neurological related to intoxication. 
car accumulator. Called
battery, electric battery or just battery, the device that stores electrical energy using electrochemical methods and then returns almost entirely, this cycle can be repeated by a number of times. This is a secondary electric generator, ie a generator can not operate without electricity previously supplied him with what is called charging.
also often called battery as many times several of them are connected in series to increase the supply voltage. Thus, a car battery is made internally by 6 elements accumulator lead-acid type, each of which supplies electricity at a voltage of about 2 V, so that all the usual 12 V supply, or 12 items at 24 V for trucks.
The term battery in Castilian, called the non-rechargeable power generators. Both battery and battery are terms from the early days of electricity, in which several cells or cells - in the first case, one above another, "stacked", and the second, attached laterally, "on battery" , as is done today in order to increase the magnitude of electrical phenomena and to study them systematically. This explanation suggests that either serve to any names, but the custom has fixed the distinction. Contents
Operating Principles of Operation battery is based essentially on some sort of reversible process, ie a process whose components are not consumed or lost result, but merely transformed into another, which in turn can return to the state first in the right circumstances. These circumstances are, in the case of batteries, the closure of the external circuit during the discharge process and the implementation of a stream, just outside during the load.
turns out that such processes are quite common, oddly enough, in the relations between the chemicals and electricity during the process called electrolysis , and voltage generators or batteries . The nineteenth century researchers devoted many efforts to observe and investigate this phenomenon, which was named polarization.
An accumulator is thus a device that takes the polarization achievable limits, and generally consists of two electrodes the same or different material, immersed in an electrolyte . History
Alessandro Volta announced his invention of the stack to the Royal London Society, March 20 of 1800. Johann Wilhelm Ritter
built his electric battery 1803. Like many other that followed, was a theoretical and experimental prototype, with no possible practical application.
In 1860 , Gaston Plante developed the first model of lead-acid battery with pretensions to be a usable device, which was only very relatively, so it was not successful. In the late nineteenth century, however, the electricity was rapidly becoming everyday items, and when I planted again to publicly explain the features of your store, in 1879 , had a better reception, so it began to be manufactured and used almost immediately, beginning an intense and ongoing process of development to perfect it and ignore its deficiencies, a process that continues today.
Thomas Alva Edison invented in 1900 , another type of battery with electrodes of iron and nickel, whose electrolyte is potassium hydroxide (KOH). First commercialized in 1908 , and are the basis of current models alkaline rechargeable or not.
Also by 1900, in Sweden, Berg invented Junger and Ni-Cd battery, which uses cadmium anodes instead of iron, being very similar to that of ferronickel in other characteristics.
battery types
As their size and other characteristics external concerns, consult this list , since many of them are common to batteries and accumulators and are standardized.
As far as concerns their internal nature, are commonly found in trade accumulators of the following types:
lead accumulator is composed of two electrodes lead, so that when the device is downloaded , is in the form of lead sulfate (PbSO4 II) embedded in a matrix of metallic lead (Pb), the electrolyte is a solution of sulfuric acid . This type of battery is still used even in many applications, including in the car. Its operation is as follows:
During the initial charging, lead sulfate (II) is reduced to lead metal at the negative pole, while the anode forms lead oxide (IV) (Pb O2) . Therefore, it is a dismutation process . No hydrogen is released, since the reduction of protons to elemental hydrogen is kinetically hindered at a lead surface, a favorable characteristic is reinforced by including the small amounts of silver electrodes. Hydrogen evolution would cause slow degradation of the electrode, helping it crumble mechanically parts of it, irreversible changes that shorten the battery service life.
During discharge processes are reversed loading. Lead oxide (IV) is reduced to lead sulfate (II), while the elemental lead is oxidized to sulfate also give lead (II). Exploit the electrons exchanged in the form of electrical current through an external circuit. It is, therefore, of a switch. The term commences elementary processes are:
PbO2 + 2 H2SO4 + 2 e--> 2 H2O + SO42-
PbSO4 + Pb + SO42--> PbSO4 + 2 e-
low discharge in the concentration of sulfuric acid because it creates lead sulphate and increases the amount of water released in the reaction. As concentrated sulfuric acid has a density greater than the dilute sulfuric acid, the acid density can be an indicator for charging status of the device.
However, this process can be repeated indefinitely, because when the lead sulfate crystals form very large, and not respond well to the processes outlined, so you lose the essential characteristic of reversibility. We then say that the battery is sulfated and must be replaced by a new one.
The batteries of this type sold today use a paste electrolyte, which does not evaporate and does a lot more comfortable and safer to use.
Alkaline Battery
ferronickel also called, the electrodes are shaped steel plates with honeycomb mesh inserts nickel oxide (NiO), which form the positive electrode, and ferrous oxide (FeO), the negative, being formed the electrolyte solution of potassium hydroxide (KOH). During the load is an anodic oxidation process and a cathodic reduction , becoming the nickel oxide in nickel and ferrous oxide in metallic iron. This reaction occurs in reverse during unloading.
In 1866, George Leclanché invented in France the "stack dry "(Zinc-Manganese Dioxide) system that still dominates the world market for primary batteries. Alkaline batteries (for "high power" or "long life") are similar to those of Leclanché, but instead of ammonium chloride, lead chloride, sodium or potassium. They last longer because zinc is not exposed to an acidic environment such as ammonium ions that cause the conventional battery. As the ions move more easily through the electrolyte, produces more power and a more stable flow.
The higher cost stems from the difficulty of sealing the cell against leakage of hydroxide. Almost all are shielded, which prevents the shedding of constituents. However, this shield does not have unlimited time. Alkaline dry cells are similar to common dry cells, with the following exceptions:
the electrolyte is basic (alkaline), because it contains KOH
the inner surface of the container of Zn is rough, this provides a larger contact area.
Alkaline batteries have a longer shelf life than the common dry cells to better withstand constant use.
voltage alkaline battery is close to 1.5 v. During unloading, the reactions in the alkaline dry cell are:
Anode: Zn (S) + 2 OH-(aq) Zn (OH) 2 (s) +2 e-
Cathode: 2 MnO2 (S) + 2 H2 O (l) + 2 e- 2MnO (OH) (s) + 2 OH-(ac)
Global: Zn (s) +2 MnO2 (s) 2H2O (l) Zn (OH) 2 (aq) + 2MnO (OH) (s)
The anode is made of a paste of zinc amalgamated with mercury (total 1%), carbon or graphite.
devices are used for complex and energy intensive. In versions 1.5 volt, 6 volt and 12 volts are used, for example, remote controls (remote control) and alarms.
alkaline manganese batteries with mercury content of around 0.1% of its total weight is an enhanced version of the previous stack, which has replaced the chloride ion conductor ammonium hydroxide Potassium (hence the name of alkaline). The battery container is steel, and disposition of zinc and manganese oxide (IV) is the opposite, placing the zinc powder now in the middle. The amount of mercury used to regulate the discharge is higher. This gives more time, more constancy in time and better performance. By contrast, the price is higher. It also provides an electromotive force of 1.5 V. It is used in most consumer devices such as portable recorders, motorized toys, electronic flashes.
The amalgamated zinc anode is the cathode material is a polarizer that is based on manganese dioxide, mercuric oxide intimately mixed with graphite, and in rare cases Ag2O silver oxide (the latter two are of use expensive, hazardous and toxic), to reduce its electrical resistivity. The electrolyte is a solution of potassium hydroxide (KOH), which presents a very low internal resistance, allowing not to take internal discharges and energy can be stored for a long time. This electrolyte in the battery business is hardened gelatin or cellulose derivatives.
This type of battery is manufactured in two ways. In one, the anode consists of a corrugated zinc strip, spirally wound from 0.051 to 0.13 mm in thickness, which is Amalgam after assembly. Two strips absorbent paper interdevanadas alkali resistant paper strip with zinc, zinc so that it extends to the top and bottom paper. The anode is insulated from the metal box with a polystyrene sleeve. The top of the stack is made of copper and makes contact with the strip of zinc to form the negative terminal of the battery. The battery is sealed with a grommet or eyelet made of neoprene. The battery casing is chemically inert to the ingredients and form the positive electrode.
Alkaline Zinc 14% (anode) Toys, tape players, cameras, recorders
22% manganese dioxide (cathode)
Coal: 2%
Mercury 0.5 to 1% (anode)
potassium hydroxide (electrolyte)
42% plastic and sheet
contains an alkaline compound called potassium hydroxide. Its duration is six times greater than that of zinc-carbon. It is composed of manganese dioxide, potassium hydroxide, zinc paste amalgamated with Mercury (total 1%), carbon or graphite. According to the European Directive of March 18, 1991, these batteries can not exceed the amount of 0.025% mercury.
This type of battery has some cons:
An alkaline battery can contaminate 175,000 liters of water, which becomes the average water consumption of all the lives of six people.
An ordinary battery, also called zinc-carbon, can contaminate 3,000 liters of water.
nasal septum perforations.
Zinc, Manganese, Bismuth, Copper and Silver: These are toxic substances that produce various alterations in human health. Zinc, Manganese and Copper are essential for life, in minute amounts, toxic in high doses. Bismuth and Silver are not essential for life.
Nickel Hydride Batteries (Ni-H)
utilize a hydroxide anode and cathode nickel alloy metal-hydride batteries. Each cell of Ni-H can provide a voltage of 1.2 V and a capacity between 0.8 and 2.3 Ah. Its energy density reaches 80 Wh / kg. These batteries are affected by the so-called memory effect, which is limited in each charging voltage or the capacity (because of a long, high temperature or high current), precluding the use of all its energy.
Nickel-Cadmium Batteries (Ni-Cd)
They use a nickel hydroxide anode and cathode of a compound of cadmium . The electrolyte is potassium hydroxide . This configuration of materials can recharge the battery once it is exhausted, for reuse. Each NiCd cell can provide a voltage of 1.2 V and a capacity between 0.5 and 2.3 Ah. No However, its energy density is only 50 Wh / kg, which means they have to be recharged every so often. They are also affected by memory effect.
Lithium-Ion Battery (Li-ion) batteries
The Lithium-Ion (Li-ion) use a lithium anode and a cathode Ion. Its development is more recent, and can reach densities of around 115 Wh / kg. Also, do not suffer from memory effect .
Lithium Polymer Batteries (Li-Poly)
are a variation of Lithium-Ion Battery (Li-ion) . Its characteristics are very similar, but allow higher energy density and a significantly higher discharge rate.
Fuel Cells
The fuel cell is not an accumulator itself, although it converts chemical energy into electricity and is rechargeable. Works with hydrogen . (Other fuels such as methane or Methanol are processed prior to hydrogen).
high capacity condenser
Although high-capacity capacitors electrochemical batteries are not strictly speaking, are now getting enough capacity large (several farads, F) so that they can be used as a battery when the power supplied are small.
parameters of a battery voltage
The or potential (in volts ) is the first parameter to consider, as is what usually determines whether the accumulator should use to which it is intended. Is fixed by the reduction potential of redox couple used, generally between 1 V and 4 V per cell.
The current that can supply the item, as ampere (A), is the second factor. Is particularly important in some cases the maximum current obtainable; p. eg., starter motors for cars require brutal efforts of the battery when put into operation (tens of A), so you must act for a short time.
electrical capacity is measured in practice by reference to the time of loading and discharge in Ah. SI unit is the coulomb (C).
1 Ah = 1000 mAh = 3600 C, 1 C = 1 Ah/3600 = 0.278 mAh.
Note, however, that, when you get indications on the body of batteries or packs, as Please charge at C/10 for 12 hours the letter C does not refer to Coulomb, but maximum load may receive the battery, so that in the previous case, if they were battery capacity 1200 mAh, you should apply a charging current = 120 mA during 1200-1210 the number of hours indicated.
The stored energy is usually measured in Wh ( watt-hour), the SI unit is the joule (unit) .
1 Wh = 3600 J = 3.6 kJ 1 J = 0.278 mWh
The resistance of the batteries is much lower than that of the batteries, allowing them to supply loads more intense than the latter, especially as transient. For example, the internal resistance of a lead-acid battery is of 0.006 ohm , and other Ni-Cd, from 0.009 ohm.
Finally, another important feature of a battery is its mass, ie, weighing, and the relationship between it and the electrical capacity (Ah / kg) or energy (Wh / kg) that can restore. In some cases it may also occupy a significant volume (m3 or liters).
The yield is the percentage ratio between the power received in the process of loading and delivery to the battery during discharge. The lead-acid battery is rated at over 90%.
batteries as contaminants
As seen, the batteries contain heavy metals and chemicals, many of them harmful environment. It is very important not to throw them away (in most countries this is not allowed) and take them to a recycling center. Currently, most vendors and specialty shops are also in charge of the batteries.
In Mexico, the release of mercury in batteries has occurred as a result of using three types of batteries: the oxide of mercury, the C-Zn and alkaline. In the first type, the metal content is 33% and were used in presentation and in other button sizes, from 1955. Theoretically, it ceased production in 1995, although there are sources that indicate that this process continues in Asia and distributed in the international market. For the second and third types of batteries, it is known that for several decades before 1990, they added mercury (0.5 to 1.2%) for best performance, with the highest alkaline content, also containing coal is sometimes contaminated with this metal naturally. In 1999, the INE requested an analysis of samples from three different brands of AA batteries normally consumed in Mexico, of which two were of Asian origin (of C-Zn) and alkaline European origin. The results were as follows: for those of Asian origin, the values \u200b\u200bwere between 0.18 mg / kg and 6.42 mg / kg, in terms of European origin the result was 0.66 mg / kg, and these amounts, equivalent to parts per million, does not exceed the limits of 0.025% under the Protocol on heavy metals taken in 1998 in Aarhus, Denmark, by members of the Economic Commission for Europe (UNECE). The previous sample was an isolated incident and it would be in the future to further analyze the mercury content in the largest possible number of brands. According to calculations presented in Table 10, an estimated 1,232 tons have been released over the past 43 years. In Mexico, the other sources of mercury are industry chlorine / soda, which is used in the process, and also products such as thermometers, various types of switches and fluorescent lamps. According to official information and is not removed mercury in Mexico, although data on imports amounting to 130 tonnes in the last three years. Mercury is a local and global pollutant par excellence. Environmental chemistry for this toxic metal is very complex, given its properties, it evaporates at room temperature, the atoms travel far, to be deposited in bodies of water are transformed into organic mercury (methyl mercury) for aerobic and anaerobic mechanisms , this is how it becomes contaminated, among others, seafood. Another form of mercury poisoning is inhalation of vapors from the mercury in its metallic form indoors. Methyl mercury can cross the placenta, accumulate and cause damage to the brain and tissues of infants who are particularly sensitive to this substance. There may also be exposed to mercury through breast milk, in this case, the effects can cause developmental problems, delays in walking, speech or mental lack of coordination, blindness and seizures. In adults, chronic exposure through ingestion of contaminated food, usually fish, can cause personality changes, loss of vision, memory or coordination, deafness, or problems in the kidneys and lungs. The International Agency for Research on Cancer (IARC, for its acronym in English) of the World Health Organization (WHO) considers to methyl mercury and its compounds as possibly carcinogenic to humans (Group 2B). Methyl mercury, which is the most toxic, accumulates in fish tissue, the larger specimens and older tend to concentrate higher levels of mercury.
Manganese: As the most used battery types are alkaline and C-Zn (approximately 76% of total batteries), the oxide manganese content in them is the pollutant that increased volume has been released into the environment over the past four decades, which is about 145.917 tons (Table 10). Regarding adverse effects on human health caused by this substance, several studies suggest serious neurological effects from oral exposure to manganese. For example, a study by the WHO reports that in 1981 poisoning was reported in a community in Japan, due to near a water well were buried around 400 pieces of batteries at a distance of approximately two meters, causing 16 cases of poisoning, three were fatal (including suicide). Manganese levels detected in water from that well was 14 milligrams per liter, while in other two wells reached levels 8 and 11 milligrams per liter. Community subjects exhibited disorders of psychological and neurological related to intoxication.
Monday, February 25, 2008
List Of Pokemon The Original 151
1.
INTRODUCTION 2. Transformation NATURAL ENERGY
3. SOLAR ENERGY COLLECTION DIRECT
1 flat plate collectors
2 Collectors concentration
3 Solar Ovens
4 solar receivers
5 solar Cooling
4. PHOTOVOLTAIC ELECTRICITY
5. SOLAR ENERGY IN SPACE
6. STORAGE DEVICES
INTRODUCTION
Sun the star by the gravitational pull of its mass, dominates the planetary system that includes the earth. By the radiation of electromagnetic energy, directly or indirectly provides the energy that sustains life on Earth, because all foods and fuels are derived ultimately from plants using energy from sunlight
solar energy, radiant energy produced in the Sun as a result of nuclear fusion reactions. Reaches the Earth through space in quanta of energy called photons (see electromagnetic radiation, photons), which interact with the atmosphere and land surface. The intensity solar radiation at the outer edge of the atmosphere, considering that the Earth is at its average distance from the sun, called solar constant and its average value is 1.37 × 106 erg/s/cm2, or about 2 cal/min/cm2.
However, this amount is not constant, since it seems to vary by 0.2% over a period of 30 years. The intensity of actual power available at Earth's surface is less than the solar constant due to absorption and scattering of radiation that causes the interaction of photons with the atmosphere.
This solar house in Corrales (New Mexico, United States) a flat-plate solar collector (bottom right) provides power to heat water pumped through the mill. Water is stored in large drums.
The intensity of solar energy available at a given point on Earth depends on a complicated but predictable, the day of the year, time and latitude. In addition, the amount of solar energy can be collected depends on the orientation of the receiver.
NATURAL TRANSFORMATION OF THE SOLAR ENERGY
natural collection of solar energy is produced in the atmosphere, oceans and plants on Earth. The interactions of the sun's energy, oceans and atmosphere, for example, produce winds, used for centuries to turn mills. Modern systems use wind power propellers strong, lightweight, weatherproof and aerodynamic design that, when attached to generators, produce electricity for local and specialist or to feed the grid in a region or community.
Nearly 30% of solar energy reaching the outer edge of the atmosphere is consumed in the water cycle, producing rain and potential energy of the mountain streams and rivers. The energy generated by these moving water passing through modern turbines is called hydropower. See also Dam, Weather, Water supply. Thanks to
process of photosynthesis, solar energy contributes to the growth of plant life (biomass), together with wood and fossil fuels from the geological point of view derived from ancient plants, can be used as fuel. Other fuels such as alcohol and methane can also be extracted from biomass.
addition, the oceans are a natural type of solar energy collection. As a result of its absorption by the oceans and ocean currents, temperature gradients occur. In some places, these vertical variations reach 20 ° C over distances of several hundred meters. When large masses of different temperatures, the thermodynamic principle predict that you can create a power generating cycle that extracts energy from the mass with higher temperature and transfer an amount to the mass with lower temperature (see thermodynamics). The difference between these energies manifests itself as mechanical energy (to drive a turbine, for example), you can connect a generator to produce electricity. These systems, called systems of ocean thermal energy conversion (OTEC), require huge energy exchangers and other devices in the ocean to produce power on the order of megawatts. See also Ocean and Oceanography.
DIRECT ENERGY COLLECTION SOLAR
The active solar heating systems include equipment that uses energy from the sun to heat and cool structures. Passive systems involve design of structures that use solar energy for cooling and heating. For example, in this house, a space solar collector used in winter when the blinds are open and the refrigerator or cooler in summer when closed. Thick concrete walls allow for fluctuations in temperature because they absorb heat in winter and outside in summer. Water tanks provide a thermal mass to store heat during the day and release it at night.
The direct collection of solar energy requires artificial devices called solar collectors designed to collect energy, often after concentrating the rays of the sun's energy, once collected, is used in thermal processes or photoelectric or photovoltaic. In thermal processes, solar energy is used to heat a gas or a liquid which is then stored or distributed. In the photovoltaic process, solar energy is converted into electricity without any intermediate mechanical device. Solar collectors fall into two main types: flat plate and concentrating.
flat plate collectors
In thermal processes collectors flat plate solar radiation intercepted an absorber plate by passing the so-called carrier fluid. This, in liquid or gaseous form is heated to cross the channel by heat transfer from the absorber plate (see Heat, Heat Transfer). The energy transfer from the carrier fluid, divided by the solar energy striking the collector and expressed as a percentage, is called the collector instantaneous efficiency. Flat plate collectors generally have one or more transparent cover plates to try to minimize heat loss from the absorber plate in an effort to maximize efficiency. Are capable of heating carrier fluids up to 82 ° C and get between 40 and 80% efficiency.
flat plate collectors have been used effectively for heating water and heating. Typical systems used for home-room fixed collectors mounted on the roof. In the northern hemisphere are oriented towards the south and in the southern hemisphere toward the North. The optimum angle for mounting the collector depends on latitude. In general, for systems that are used throughout the year, such as producing hot water collectors are inclined (to the horizontal plane) at an angle equal to 15 ° latitude and are oriented 20 ° or 20 ° S latitude N. latitude
addition
plate collectors flat, the typical systems of heating and hot water are formed by circulating pumps, temperature sensors, automatic controllers to activate the pump and a storage device. The fluid can be both air and liquid (water or water mixed with antifreeze), while bedrock or an insulated tank used as a means of storing energy.
The collector plates using the sun's energy to heat a fluid carrier, in turn, provides heat for use in a home. The carrier fluid, water in this case, flows through copper pipes in the solar collector during the process some of the energy absorbed solar. Then moves to a heat exchanger where it heats the water to be used at home. Finally, a bomb once again leads the fluid to the solar collector to repeat the cycle. Collectors
concentration
For applications such as air conditioning and central power generation and heat to meet industry needs large, flat plate collectors do not provide, in general, fluids with temperatures high enough to be effective . Can be used in a first phase, and then the fluid is treated with conventional means of heating. Alternatively, you can use concentrating collectors more complex and costly. These are devices that reflect and concentrate solar energy incident on a small receiving area. As a result of this concentration, the intensity of solar energy and temperature increases of receptor (called 'white') can come to several hundreds or even thousands of degrees Celsius. Concentrators must move to follow the sun if they are to operate effectively, the devices used for this are called heliostats.
solar ovens solar ovens are an important application of high temperature hubs. The largest, located in Odeillo in the French Pyrenees, has 9,600 reflectors with a total surface of about 1,900 m2 to produce temperatures of 4,000 ° C. These ovens are ideal for research, for example, materials research, which require high temperatures in environments free of pollutants.
central Receivers
centralized generation of electricity from solar energy is under development. The concept of central receiver or power tower, an array of reflectors mounted on computer-controlled heliostats reflect and concentrate the sun's rays on a water boiler located on the tower. The generated steam cycles can be used in conventional power plants and generate electricity.
Solar cooling
cold may occur with the use of solar energy as a source of heat in an absorption cooling cycle (see Refrigeration). One of the standard system components by absorption cooling, called generator, you need a heat source. Since, in general, require temperatures above 150 ° C for absorbing devices work effectively, concentrating collectors are more suitable than flat plate.
PHOTOVOLTAIC ELECTRICITY In a photovoltaic cell, light excites electrons between layers of silicon semiconductor materials. This produces electrical currents.
solar cells made from thin wafers of silicon, gallium arsenide or other semiconductor material in the crystalline state, convert radiation directly into electricity. Cells are now available with conversion efficiencies greater than 30%. Through the connection of many of these cells into modules, the cost of photovoltaic electricity has been greatly reduced. The current use of solar cells is limited to low power devices, remote maintenance free, as buoys and spacecraft equipment.
SOLAR ENERGY IN THE SPACE
A futuristic project proposed to produce large-scale power to situate solar modules in orbit around the Earth. They concentrated energy of sunlight become microwave antennas to be issued to land for conversion into electrical energy. To produce as much power as five large nuclear power plants (one billion watts each) would have to be assembled in orbit several square kilometers of collectors, with a weight of more than 4000 t, would need an antenna on the ground of 8 m in diameter. It could build smaller systems for islands remote, but the economy of scale advantages for a single high-capacity system (see Astronautics).
ENERGY STORAGE DEVICES FOR SOLAR
Due to the intermittent nature of solar radiation as energy source during periods of low demand the excess is stored solar energy to cover needs when availability is insufficient. In addition to simple storage systems such as water and rock, can be used, particularly in refrigeration applications, more compact devices that rely on phase changes characteristic of eutectic salts (salts that melt at low temperatures). The batteries can be used to store excess electricity produced by wind or photovoltaic devices (see Drums). A global concept is to deliver power over existing networks and use these as additional sources when solar availability is insufficient. However, the economy and reliability of this project sets limits for this alternative.
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