(Need-Want-Desire) The basic thing that leads people towards the sky high success in 3 dimensional life
Tuesday, May 29, 2012
Do not listen to him
While I was young, wise man use to say, “Son; make your fate by your own”. I always been very attentive to wise man as well careful too. But one thing confused me that; how do I can create my own fate while there is one god and he send us in the world and nothing can happen with out his permission. It was very confusing to me. I never thaught abut religion before that. I use to follow my parents and that my guardians tell me to do. I use to have my prayer regularly by going to mosque. At the age of sixteen, in sweet sweet sixteen some thing happened to me and I started experimenting of my luck and religion also.
At the first step I just start deny of existence of religion and god and any luck of mine. I expressed it to my guardians and relatives and friends too. I knew it was safe because they will not atleast do any thing like the extremist Muslims; particularly the follower of Bin-Laden or Taleban of afganisthan.
Love was the barricade of them.
I observed that they are getting angry with my talkings and thaught. When ever I use to discuss about religion they became hrash with me. I took note it in my head. Then agian I start searching for the answer to my question of thaught. At the age of 18 I got a chance to visit India for doing my honors graduation in University of Delhi. I alone visited all the mosque of Delhi as well the temple of Delhi. Not only that I visited the famous places where pilgrims use to go for showing their devotaion towards God the almighty.
I think I learn huge thing that people will get surprise when they know it. In one sentence I can say to all what I learnt there.I learnt that going any where in search of God is the most foolish job in this world and making experiment with life is always dangerous for bright future.
Last of all my advice is to the young is, never listen to wise man if you meet him any where in any part of this world
Saturday, May 12, 2012
Delaying to use the alternative and renewable energy? – Know detail about electricity storing system in a solar PV system
Earlier I have discussed on the necessity of using alternative clean and green energy such as solar photo voltaic (PV) panels for the resources of clean and green energy. Fossil fuel and other resources of power and electricity has limit and will be finished off with in near future. In early version I have discussed on PV panels and how they work. Not only in my early article; there are many readings and books are available to take knowledge on solar PV panels in market now a days. Many analyst and expert had discussed on solar PV panels in different magazine and news paper in recent time.
There are some more components and equipments are using in a solar powered electric system. Those equipments are very important role to play in a solar powered system. I think people should know about these for their knowledge and usability.
One important component in the PV panels is the storage system. It is required to have a storage system in a solar powered electricity generating system. The major role of this storage system is to store the electricity and release it when ever required for. As we know Electric power is generated only during day time by PV panels. But we need light at night. So some sort of storage systems has to be used with PV system. Although various types of batteries are available in the market, lead-Acid batteries are widely used in PV systems. Many of us may know that In 1859 French physicist Gaston Planté invented this rechargeable battery. Despite having a very low energy-to-weight ratio and a low energy-to-volume ratio, they have the ability to supply high surge current and relatively large power-to-weight ratio. These features, along with their low cost, make them attractive for use in motor vehicles and now in PV systems. Their huge Ampere-Hour capacity makes them suitable for PV system.
The lead acid batteries may be divided in to some parts.
Parts of a Lead-acid Battery:
A battery consists of a number of cells and each cell of the battery consists of (1) positive and negative plates (2) separators (3) electrolyte and (4) the container. Different parts of a lead-acid battery are described below:
(1) Plates. A plate consists of a lattice type of grid of cast antimonied lead alloy which is covered with active material. The grid not only serves as a support for the fragile active material but also conducts electric current. Grids for the positive and negative plates are often of the same design although negative- plate grids are made some¬what lighter.
(2) Separators. These are thin sheets of a porous material placed between the positive and negative plates for preventing contact between them and thus avoiding internal short-circuiting of the battery. A separator must, however, be sufficiently porous to allow diffusion or circulation of electrolyte between the plates. These are made of especially-treated cedar wood, glass wool mat, micro porous rubber (mipor), micro porous plastics (plastipore, miplast) and perforated p.v.c. In addition to good porosity, a separator must possess high electrical resistance and mechanical strength.
Separators: (1) and (2) Miplast type (3) Perforated type
(3) Electrolyte. It is dilute sulphuric acid which fills the cell compartment to immerse the plates completely.
Battery container
Followings are the parts of the lead acid battery picture shown as parts separately.
1. Negative plate 2. Separator 3. Positive plate. 4. Positive group 5. Negative group 6. Negative group grooved support block 7. Lug 8. Plate group 9. Guard screen 10. Guard plate 11. Cell cover 12. Plug washer 13. Vent plug 14. Monoblock jar 16. Supporting prisms of + ve group 16. Inter-cell connector 17. Terminal lug 18. Screw 19. Washer 20. nut 21. Rubber packing 22. Sealing compound.
Discharging:
When the cell is fully charged, its positive plate or anode is Pb02 and the negative plate or cathode is Pb. When the cell discharges i.e. it sends current through the external load, then H2SO4 is dissociated into positive H2 and negative S04 ions. As the current within the cell is flowing from cathode to anode, H2 ions move to anode and SO4 ions move to the cathode.
At anode (Pb02), H2 combines with the oxygen of Pb02and H2SO4 attacks lead to form PbS04.
CHARGING
When the cell is recharged, then H2 ions move to cathode and S04 ions go to anode and the following changes take place:
Hence, the anode and cathode again become PbO2 and Pb respectively.
It will be noticed that during charging :
The anode becomes dark chocolate brown in color (Pb02) and cathode becomes grey metallic lead (Pb)Due to consumption of water, specific gravity of H2SO4. is increased
There is a rise in voltage,
Energy is absorbed by the cell
Efficiency:
Ideally, the charging and discharging processes of the lead-acid system should be reversible. In reality, however, they are not. Some of the electrical energy intended for charging is lost in the internal resistance and is converted to heat. When hydrogen is lost, it also represents an energy loss. Typically, the charging process is about 95% efficient. The discharge process also results in some losses due to internal resistance of the battery, so only about 95% of the stored energy can be recovered. The overall efficiency of charging and discharging a lead-acid battery is thus about 90%.
Since battery losses to internal resistance are proportional to the square of the current, this means that high current charging or high current discharging will tend to result in higher internal losses and less overall performance efficiency.
Amount of stored energy:
The amount of energy stored in a battery is commonly measured in ampere hours. While ampere hours are technically not units of energy, but, rather, units of charge, the amount of charge in a battery is approximately proportional to the energy stored in the battery. If the battery voltage remains constant, then the energy stored is simply the product of the charge and the voltage.
Effect of DOD on Life-Cycle:
The following Figure shows how the depth of discharge affects the number of operating cycles of a deep discharge battery. The PV system designer must carefully consider the trade-off between using more batteries operating at shallower discharge rates to extend the overall life of the batteries vs. using fewer batteries with deeper discharge rates and the correspondingly lower initial cost.
Lead-acid battery lifetime in cycles vs. depth of discharge per cycle
Vented and nonvented batteries:
In certain lead-calcium batteries, minimal hydrogen and oxygen are lost during charging. This means minimal water is lost from the electrolyte. As a result, it is possible to seal off the cells of these batteries, making them essentially maintenance free. The trade-off, however, is that if these batteries are either purposely or inadvertently discharged to less than 75% of their maximum charge rating, their expected lifetime may be significantly shortened.
Lead-antimony electrodes, on the other hand, may be discharged to 20% of their maximum rating. This means that a 100 Ah lead-calcium battery has only 25 Ah available for use, while a 100 Ah lead-antimony battery has 80 Ah available for use, or more than 3 times the availability of the lead-calcium unit. However, the lead-antimony unit produces significantly more hydrogen and oxygen gas from dissociation of water in the electrolyte, and thus water must be added to the battery relatively often to prevent the electrolyte level from falling below the top of the electrodes. Water loss can be reduced somewhat by the use of cell caps that catalyze the recombination of hydrogen and oxygen back into water, which returns to the cell.
Chemistry of the Nickel Cadmium Storage Battery:
Ni-Cd batteries use nickel oxi-hydroxide for the anode plates and finely divided cadmium for the cathode plates.
The electrolyte in the Ni-Cd system is potassium hydroxide (KOH).
The NiOOH anode is generally made of nickel fibers mixed with graphite- or nickel-coated plastic fibers. Small quantities of other materials such as barium and cobalt compounds are also added to improve performance. The cathode is also frequently made of a cadmium-coated plastic fiber. If the cathode is not a coated plastic, then it is commonly mixed with iron or nickel. The fiber structures of anode and cathode maximize the surface area while minimizing the amount of relatively expensive nickel and cadmium required for the electrodes.
On discharge, the NiOOH of the positive plate is converted to Ni(OH)2 and the cadmium metal of the negative plate is converted to Cd(OH)2.
The basic reactions are:
At the positive plate: NiOOH + H2O + e- = Ni(OH)2+OH
At the negative plate: Cd + 2OH- = Cd(OH)2 + 2e-
Overall: 2NiOOH + Cd + 2H20 = 2Ni(OH)+Cd(OH)
The voltage of the fully charged cell is 1.29 V. Unlike the lead-acid system where the specific gravity of the electrolyte changes measurably during discharge or charge, the KOH electrolyte of the Ni-Cd system changes very little during battery operation.
Ni-MH: (Nickel Metal Hydride) `
Another technology that is becoming very popular, particularly in smaller applications such as camcorders and laptop computers, is the nickel-metal hydride (NiMH) battery. This battery replaces the cadmium cathode with an environmentally benign metal hydride cathode, allowing for higher energy density at the cathode and a correspondingly longer lifetime or higher capacity, depending on the design goal. The anode is the same as in the Ni-Cd cell and KOH is used as the electrolyte. The overall discharge reaction is
MH + NiOOH = M + Ni(OH)2
Lithium Ion (Li-Ion) Battery:
Lithium-Ion battery is an advanced battery. Lithium ion batter has high energy density, low self discharge and no memory effect. These batteries are used where smaller and light weight batteries are required such as cell phones and laptop computers.
However the main disadvantages of these batteries are the high price and fewer charge/discharge cycles
Saturday, February 11, 2012
Right time to use Solar Photo Voltaic (PV) panels and Solar System Solution for power and electricity
. What will happen when the fossil fuel and other resources of power and electricity will end within few years? With the current world situation this question has the most logical base and why not the reserves of crude oil is over 1000 billion barrels that is available for usage and it is assumed that with the current utilization of 84.1 millions barrels a day, the world can run only another 32 (Thirty Two) years. After the stock report of fossil fuel; let’s check out where this fuel is utilizing: - the main consumption of fossil fuel is to produce the power and electricity. The second most usage is to run the vehicle and to run a smooth transportation system too. Other than these: mills, factories, heavy industrial instruments and equipments are run by the fuel. So, it is natural to come in mind what will happen after 32 years from now when we will finish off all the reserve of oil. Will we stop our power and electricity production? Will we stop the heavy industries? Will we stop the transportation and vehicle? Any one can guess that is not possible for us. World can’t pass a second with out power and energy nowadays. So, there is need to use of alternative and renewable energy resources to make substitute of the fossil fuel and the coal & natural gas. The sustainable renewable energy is getting popular as clean and green energy. Most of the countries are investing on this natural and renewable energy sector. There is no other way left for the human civilization ahead other than this. The next generation survival is depending on the perfection of proper utilization of invested capital in research of sustainable and renewable energy resources production and implementation system. USA president Mr. Barak Obama called for the country to reduce its oil import by one third by the year 2025. This is not that they are in short of budget for buying oil from other countries but they would like to secure its energy supply in the future. May be question will arise how? We can mention Mr. Obama’s speeches here,” When I was elected to this office, America imported 11(eleven) million barrels of oil a day. By little more than a decade from now we will cut that by one third”. Actually his emphasis on using of alternative of oil and fossil fuel; he said “The only way for American energy supply to be truly secure is by permanently reducing our dependence on oil. We are to have to find ways to boost our efficiency so we use less oil. We have got to discover and produce cleaner renewable sources of energy that also produce less carbon pollution”. He said that meeting this new goal of cutting US oil dependence depends largely on two things finding and producing more oil at home and reducing our dependence on oil with cleaner alternative fuels and greater efficiency. The USA president pointed on not to make a quick fix of the solution. Here we can mention another project that is completely hydro project and the location is in Himachal. This project is established by a consortium of TATA Power and Norwegian hydro power company. This project is build to produce 236 Mega Watt of electricity in Chenab Valle in Himachal Pradesh, India. In Srilanka rural electricity schemes has launched very recently. Several projects are going to establish by the government of Srilanka to achieve target of 100 percentages electricity needs of country’s rural sectors by 2012 set by Minister Patali Chapika Ranwake. The 4th project is for lighting Srilanka, Ranpura, Kague, Central province. The rural electricity project No.8 issued by the power and energy commission is the project under which new electricity connection had been provided for 720 houses in the Galle and Matara districts. There is a plan to another 516 electricity schemes of Rs. 85.7 million are in operation covering Elipitya, Nagoda, Karon, Deniya, Yakkalamulla,Beddegama and Thavalama divisions in the Gale district. While 203 electricity schemes will be started at the cost of Rs. 134.1 million of cover Kotapola, Pitabed, Passara, Dickweili and Akuresra DS divisions in Matara district. The International Energy Agency 794(IEA) is saying that the wide spread development of “Smart Grids” networks that monitors and manage the transport of electricity from all sources to meet the varying electricity demands of end users is crucial to achieving a more secure and sustainable future. Not only that the World Bank has taken an initiative to allocate the loan and subsidies in the sector of renewable energy nowadays. The IMF has prepared fund for set up the renewable energy plant, such as; the electricity production by the photo voltaic (PV) solar cell
I have tried to give some detail discussion and information in this article so that people can get a general idea about the solar panel that is used for generation of electricity. Basically the solar Photovoltaic (PV) or solar cells are PN junction Semiconductor devices. It converts sun light into direct current electricity. There are some types of solar cells or PV solar panels in market. Such as:
Mono Crystalline Solar cell
Poly Crystalline Solar Cell
Amorphous silicon solar cell
Flexible amorphous silicon
We can remember that one silicon solar cell produces 0.5V to 0.6V; these cells are combines together to get a module. Usually 33/36 cells are connected together to make one module. This connection are made keeping the fact in tact the cells are connected electrically in series and/or parallel circuits to produce higher voltages, currents and power levels. One module is capability to produce enough voltage to charge 12 volt batteries and run pumps and motors. The PV module is basic building block of a PV power system. Most of the time PV modules are combined in series parallel manner to make PV array of required power complete power-generating unit.
For two cells connected in series, the current through the two cells is equal. The sum of total voltage produced is the total of the individual cell voltages. As the current should same, a mismatch in current means that the total current from the configuration is equal to the lowest current.
Incase of parallel connected solar cell the voltage across the cell combination is always the same and the total current from the combination is the sum of the currents in the individual cells.
The performance of PV modules and arrays are generally rated according to their maximum DC power output (watts) under. Standard Test Conditions (STC).
Standard Test Conditions are defined by a module (cell) operating temperature of 25o C (77 F), and incident solar irradiance level of 1000 W/m2 and under Air Mass 1.5 spectral distribution. Since these conditions are not always typical of how PV modules and arrays operate in the field, actual performance is usually 85 to 90 percent of the STC rating.
Today’s photovoltaic modules are extremely safe and reliable products, with minimal failure rates and projected service lifetimes of 20 to 30 years.
With the above PV modules the solar systems and electricity generating solutions are developed.
These solutions can be different in category. Following is the category of solution those are possible to develop usually. They are:
1. Stand-alone PV systems
(a) Simple single module DC system (PV Home system)
(b) Large DC PV system
(c) PV system for DC and AC power
2. Hybrid PV systems:
(a) Hybrid-PV diesel
(i) Hybrid PV-Diesel system for DC and AC power
(ii) Hybrid PV-Diesel system for DC and AC with generator
for rectified DC
(c) Hybrid PV-Thermal systems
(d) Hybrid PV-Wind systems
3.Grid-connected PV power systems
(a) Self-commutated
(b) Line commutated
> Simple single module DC PV systems (PV Home systems) are used for low cost rural electrification. Usually a single module is connected to the load for sunny day use.
> Simple single module DC PV system (PV Home system) is connected to a single low cost battery through a simple charge controller as the regulator that is connected to a CFL. The regulator may have a relay that could tern off the light if the battery voltage became too low. The user would have to wait until the module charged the battery back to an acceptable intermediate voltage before they could turn on the light again.
> Large DC PV power system consists of large number of modules and large number of batteries to drive heavy DC loads. A large heavy duty controller having high current driving capability is required. Usually Loads are connected through the charge controller via DC circuit breaker distribution box.
> PV system for DC and AC power consists of large number of modules. Charge controller regulates the charging and discharging of the battery and the DC loads are supplied power through controller. Inverter generates AC power for the AC loads such as computers, fax machine, radio, TV, VCR and CD players.
Hybrid PV-Diesel system
(i) Hybrid PV-Diesel system for DC and AC power:
Instead of relying purely on PV system for power, a system can be designed with other generators available as well. A common choice is a diesel generator. This generator produces AC power for AC loads which can be passed directly on to AC loads through transfer switches. Generator power can also be used after (converting AC to DC) rectification to charge batteries or to supply required DC input to the inverter.
(ii) Hybrid PV-Diesel system for DC and AC with generator
for rectified DC
A hybrid system can be designed to have the generator act only as a battery charger. AC power is not used to run the AC loads. All AC loads are driven by the power generated by the inverter only. The generator is turned on when the battery voltage is very low or weather is bad. After rectification generator output is used to charge the battery.
The generator needs to operate only for few hours to recharge batteries.
Generator is operated at its full rated output for maximum output and
long life. When batteries are sufficiently recharged, the generator is turned off, and the finishing charge is supplied by the solar modules. If the bad weather continues, the generator is turned on again for a few days, and repeats the charging process. In this way the battery is kept fully charged having longer useful life.
(iii) Hybrid PV-Thermal systems
Hybrid PV-thermal systems, sometimes known as hybrid PV/T systems or PVT, are systems that convert solar radiation into electrical and thermal energy. These systems combine a photovoltaic cell, which converts electromagnetic radiation (photons) into electricity, with a solar thermal collector, which captures the remaining energy and removes waste heat from the PV module. Photovoltaic (PV) cells suffer from a drop in efficiency with the rise in temperature due to increased resistance. Such systems can be utilized to carry heat away from the PV cells thereby cooling the cells and thus improving their efficiency by lowering resistance.
Hybrid PV-Wind systems
There are some places where wind speeds are often low in periods when the sun resources are at their best. On the other hand, the wind is often stronger in seasons when there are less sun resources. That can make solar PV-wind hybrid solutions an alternative to consider. Even during the same day, in many regions worldwide or in some periods of the year, there are different and opposite wind and solar resource patterns. And those different patterns can make the hybrid systems the best option for electricity production.
Hybrid PV-Wind system is the combination of PV and wind turbine for the generation of electricity.
Grid-connected PV systems
DC power generated by PV is converted into AC and is supplied to the national grid. Energy storage is not necessary in this case. On sunny days, the solar generator provides power, e.g., for the electrical appliances in the house. Excess energy is supplied to the national grid. During the night and overcast days, the house draws its power from the grid. In this way, the electricity grid can be regarded as a large “storage unit”. In the case of a favorable rate-based tariff for PV electricity, as in force in some countries, it is more advantageous to feed all solar electricity into the grid.
Grid-connected PV systems can be subdivided into two kinds
Decentralized Grid-connected PV systems and
Centralized Grid-connected PV systems
Single phase less than or equal to 25kW
Three phase less than or equal to 300kW
Decentralized Grid-connected PV systems
Decentralized Grid-connected PV systems have mostly a small power range and are installed on the roof-top of buildings (roof-top or flat-roof installation) or integrated into building facades.
For example, in Germany around 80% of the more than 50,000 existing grid-connected PV systems are installed either on the roof-top of a building or integrated into a building façade. The benefit of the installation of a PV system into or onto a building is that no separate area for the solar generator is needed.
Central Grid-connected PV systems:
Central Grid-connected PV systems have an installed power up to MW range. With such central photovoltaic power stations it is possible to feed directly into the medium or high voltage grid. Mostly central photovoltaic power stations are set on unused land, but in some cases an installation on buildings, mostly on the flat roof of greater buildings, is also possible.
The main equipments in a solar home and commercial system connection set-ups are:
1. PV solar panels/module
2. Battery for storing the electricity
3. Charge controller for the battery indicator
4. Inverter for converting the DC current to AC out put usage equipment
5. Accessories as cable, switch board, switch, clip, array junction box for large system, main junction box, and steel frame structure to set-up the PV panels and some more as required to design and looking the solution in descent shape.
I have tried to give some detail discussion and information in this article so that people can get a general idea about the solar panel that is used for generation of electricity. Basically the solar Photovoltaic (PV) or solar cells are PN junction Semiconductor devices. It converts sun light into direct current electricity. There are some types of solar cells or PV solar panels in market. Such as:
Mono Crystalline Solar cell
Poly Crystalline Solar Cell
Amorphous silicon solar cell
Flexible amorphous silicon
We can remember that one silicon solar cell produces 0.5V to 0.6V; these cells are combines together to get a module. Usually 33/36 cells are connected together to make one module. This connection are made keeping the fact in tact the cells are connected electrically in series and/or parallel circuits to produce higher voltages, currents and power levels. One module is capability to produce enough voltage to charge 12 volt batteries and run pumps and motors. The PV module is basic building block of a PV power system. Most of the time PV modules are combined in series parallel manner to make PV array of required power complete power-generating unit.
For two cells connected in series, the current through the two cells is equal. The sum of total voltage produced is the total of the individual cell voltages. As the current should same, a mismatch in current means that the total current from the configuration is equal to the lowest current.
Incase of parallel connected solar cell the voltage across the cell combination is always the same and the total current from the combination is the sum of the currents in the individual cells.
The performance of PV modules and arrays are generally rated according to their maximum DC power output (watts) under. Standard Test Conditions (STC).
Standard Test Conditions are defined by a module (cell) operating temperature of 25o C (77 F), and incident solar irradiance level of 1000 W/m2 and under Air Mass 1.5 spectral distribution. Since these conditions are not always typical of how PV modules and arrays operate in the field, actual performance is usually 85 to 90 percent of the STC rating.
Today’s photovoltaic modules are extremely safe and reliable products, with minimal failure rates and projected service lifetimes of 20 to 30 years.
With the above PV modules the solar systems and electricity generating solutions are developed.
These solutions can be different in category. Following is the category of solution those are possible to develop usually. They are:
1. Stand-alone PV systems
(a) Simple single module DC system (PV Home system)
(b) Large DC PV system
(c) PV system for DC and AC power
2. Hybrid PV systems:
(a) Hybrid-PV diesel
(i) Hybrid PV-Diesel system for DC and AC power
(ii) Hybrid PV-Diesel system for DC and AC with generator
for rectified DC
(c) Hybrid PV-Thermal systems
(d) Hybrid PV-Wind systems
3.Grid-connected PV power systems
(a) Self-commutated
(b) Line commutated
> Simple single module DC PV systems (PV Home systems) are used for low cost rural electrification. Usually a single module is connected to the load for sunny day use.
> Simple single module DC PV system (PV Home system) is connected to a single low cost battery through a simple charge controller as the regulator that is connected to a CFL. The regulator may have a relay that could tern off the light if the battery voltage became too low. The user would have to wait until the module charged the battery back to an acceptable intermediate voltage before they could turn on the light again.
> Large DC PV power system consists of large number of modules and large number of batteries to drive heavy DC loads. A large heavy duty controller having high current driving capability is required. Usually Loads are connected through the charge controller via DC circuit breaker distribution box.
> PV system for DC and AC power consists of large number of modules. Charge controller regulates the charging and discharging of the battery and the DC loads are supplied power through controller. Inverter generates AC power for the AC loads such as computers, fax machine, radio, TV, VCR and CD players.
Hybrid PV-Diesel system
(i) Hybrid PV-Diesel system for DC and AC power:
Instead of relying purely on PV system for power, a system can be designed with other generators available as well. A common choice is a diesel generator. This generator produces AC power for AC loads which can be passed directly on to AC loads through transfer switches. Generator power can also be used after (converting AC to DC) rectification to charge batteries or to supply required DC input to the inverter.
(ii) Hybrid PV-Diesel system for DC and AC with generator
for rectified DC
A hybrid system can be designed to have the generator act only as a battery charger. AC power is not used to run the AC loads. All AC loads are driven by the power generated by the inverter only. The generator is turned on when the battery voltage is very low or weather is bad. After rectification generator output is used to charge the battery.
The generator needs to operate only for few hours to recharge batteries.
Generator is operated at its full rated output for maximum output and
long life. When batteries are sufficiently recharged, the generator is turned off, and the finishing charge is supplied by the solar modules. If the bad weather continues, the generator is turned on again for a few days, and repeats the charging process. In this way the battery is kept fully charged having longer useful life.
(iii) Hybrid PV-Thermal systems
Hybrid PV-thermal systems, sometimes known as hybrid PV/T systems or PVT, are systems that convert solar radiation into electrical and thermal energy. These systems combine a photovoltaic cell, which converts electromagnetic radiation (photons) into electricity, with a solar thermal collector, which captures the remaining energy and removes waste heat from the PV module. Photovoltaic (PV) cells suffer from a drop in efficiency with the rise in temperature due to increased resistance. Such systems can be utilized to carry heat away from the PV cells thereby cooling the cells and thus improving their efficiency by lowering resistance.
Hybrid PV-Wind systems
There are some places where wind speeds are often low in periods when the sun resources are at their best. On the other hand, the wind is often stronger in seasons when there are less sun resources. That can make solar PV-wind hybrid solutions an alternative to consider. Even during the same day, in many regions worldwide or in some periods of the year, there are different and opposite wind and solar resource patterns. And those different patterns can make the hybrid systems the best option for electricity production.
Hybrid PV-Wind system is the combination of PV and wind turbine for the generation of electricity.
Grid-connected PV systems
DC power generated by PV is converted into AC and is supplied to the national grid. Energy storage is not necessary in this case. On sunny days, the solar generator provides power, e.g., for the electrical appliances in the house. Excess energy is supplied to the national grid. During the night and overcast days, the house draws its power from the grid. In this way, the electricity grid can be regarded as a large “storage unit”. In the case of a favorable rate-based tariff for PV electricity, as in force in some countries, it is more advantageous to feed all solar electricity into the grid.
Grid-connected PV systems can be subdivided into two kinds
Decentralized Grid-connected PV systems and
Centralized Grid-connected PV systems
Single phase less than or equal to 25kW
Three phase less than or equal to 300kW
Decentralized Grid-connected PV systems
Decentralized Grid-connected PV systems have mostly a small power range and are installed on the roof-top of buildings (roof-top or flat-roof installation) or integrated into building facades.
For example, in Germany around 80% of the more than 50,000 existing grid-connected PV systems are installed either on the roof-top of a building or integrated into a building façade. The benefit of the installation of a PV system into or onto a building is that no separate area for the solar generator is needed.
Central Grid-connected PV systems:
Central Grid-connected PV systems have an installed power up to MW range. With such central photovoltaic power stations it is possible to feed directly into the medium or high voltage grid. Mostly central photovoltaic power stations are set on unused land, but in some cases an installation on buildings, mostly on the flat roof of greater buildings, is also possible.
The main equipments in a solar home and commercial system connection set-ups are:
1. PV solar panels/module
2. Battery for storing the electricity
3. Charge controller for the battery indicator
4. Inverter for converting the DC current to AC out put usage equipment
5. Accessories as cable, switch board, switch, clip, array junction box for large system, main junction box, and steel frame structure to set-up the PV panels and some more as required to design and looking the solution in descent shape.
Monday, February 28, 2011
Sunday, February 20, 2011
Laughter is the best medicine
When the steamer started the sun was direct on the head and it was about 11: 50 in the morning. There were almost 300 passengers aboard on the steamer. All were heading through an unknown place. It was a refreshment journey program set by the office management where wise man got a new job. It was the third day of his office. The destination was not set up before journey that seems very existing to wise man and same to all the office staff. It was decided the steamer will continue its movement for 4 hours. After 4 hours it will sail back to the dock again.
It was a shiny morning of winter. The steamer sailed for an unknown goal. On rooftop there were some umbrella tables and chairs to sit on. Wise man stayed there for couple of hour and came down at the 2nd floor of the steamer where a stage had been made for musical, magical and some other cultural program.
A band was performing and presenting song to the guest. But the audience seems a bit bored with the song presenter. Although the instrument player were skilled and proving it by presenting quality music. One of the audiences sends a request to the singer for singing a song of a popular band. The singer talked with the instrument player and start song with rhythm. But the surprise was he sang with the wrong tune and the whole music stopped at the time. The music start and the singer again and fail to put the tone in his voice again. That proved him as an inexpert customer in this business. It became fun to every body. To keep his prestige the singer shouted that the sound system was not good and left the stage.
Wise man laughed a lot at the scene. And one critic from audience took the mike and started a folk song. But his voice was worse than the singer and all the audience start leaving the floor. No sooner the singer made his scale higher, the sound system circuit blown up and the electric wire was caught by fire. And all the audience start running to the stage and push out the singer from mike. Some hurriedly run on ground floor and took water and put off the fire. Every body experienced a divine punishment towards the singer to irritate the gentle men during their refreshment.
At the end every body feel very refreshed off when they are back to the port again.
Wise man thought laughter is the best medicine of all.
It was a shiny morning of winter. The steamer sailed for an unknown goal. On rooftop there were some umbrella tables and chairs to sit on. Wise man stayed there for couple of hour and came down at the 2nd floor of the steamer where a stage had been made for musical, magical and some other cultural program.
A band was performing and presenting song to the guest. But the audience seems a bit bored with the song presenter. Although the instrument player were skilled and proving it by presenting quality music. One of the audiences sends a request to the singer for singing a song of a popular band. The singer talked with the instrument player and start song with rhythm. But the surprise was he sang with the wrong tune and the whole music stopped at the time. The music start and the singer again and fail to put the tone in his voice again. That proved him as an inexpert customer in this business. It became fun to every body. To keep his prestige the singer shouted that the sound system was not good and left the stage.
Wise man laughed a lot at the scene. And one critic from audience took the mike and started a folk song. But his voice was worse than the singer and all the audience start leaving the floor. No sooner the singer made his scale higher, the sound system circuit blown up and the electric wire was caught by fire. And all the audience start running to the stage and push out the singer from mike. Some hurriedly run on ground floor and took water and put off the fire. Every body experienced a divine punishment towards the singer to irritate the gentle men during their refreshment.
At the end every body feel very refreshed off when they are back to the port again.
Wise man thought laughter is the best medicine of all.
Thursday, February 10, 2011
Wise man wrote article
Wise man had to earn from online. So he complete profile and apply at oDesk. The First interview was taken for writing an article. Al though wise man had some writing experiences but this was the first time he was writing professionally. So a rare kind of feeling about the writing worked for wise man. The key word given to him was “FURNITURE RELATED WEBSITE”
I took permission to publish the writing at my blog you can find it as below:
There is a common saying in our society; might not be pleasant for females to hear with, “Wife becomes furniture after 2(Two) years of marriage”. Neither have I wanted to go for any argument with it. Rather I like to discuss on the furniture related website. Furniture remains no longer a necessity; it became part and parcel of our daily life. For the reason now a day the show rooms of furniture are mushrooming all around the locality. Of course there are lots of people who are not capable to visit all those show rooms whenever the requirement arises due to work load and lack of time. There are many of them who may have no idea that they can deal with these problems by visiting furniture related web sites. One can buy furniture no matter weather he/she is seating at home or in office. There are lots of reputed and renowned companies are having their own websites. All the products with their images and price list are available in their website also. So an individual can select an item by his/her own preferences. Most of the companies have home delivery system. Once the order is taken place and the payment terms had been settled; it’s the responsibility of delivery team to reach the product to destination. The companies may have the data from customers by website hit count down system and feed back form. These data may help to boost up their business also. The opportunity of business becomes much more expanded by website and online transaction system. More over the scope for foreign business gets increased by dint of virtual effect of World Wide Web. People, who want to use the luxurious imported furniture, can be guided to desired company and product of their preferences as well. So, we can say at the end that the furniture related website can help to bloom and develop the business, customers and products.
I took permission to publish the writing at my blog you can find it as below:
There is a common saying in our society; might not be pleasant for females to hear with, “Wife becomes furniture after 2(Two) years of marriage”. Neither have I wanted to go for any argument with it. Rather I like to discuss on the furniture related website. Furniture remains no longer a necessity; it became part and parcel of our daily life. For the reason now a day the show rooms of furniture are mushrooming all around the locality. Of course there are lots of people who are not capable to visit all those show rooms whenever the requirement arises due to work load and lack of time. There are many of them who may have no idea that they can deal with these problems by visiting furniture related web sites. One can buy furniture no matter weather he/she is seating at home or in office. There are lots of reputed and renowned companies are having their own websites. All the products with their images and price list are available in their website also. So an individual can select an item by his/her own preferences. Most of the companies have home delivery system. Once the order is taken place and the payment terms had been settled; it’s the responsibility of delivery team to reach the product to destination. The companies may have the data from customers by website hit count down system and feed back form. These data may help to boost up their business also. The opportunity of business becomes much more expanded by website and online transaction system. More over the scope for foreign business gets increased by dint of virtual effect of World Wide Web. People, who want to use the luxurious imported furniture, can be guided to desired company and product of their preferences as well. So, we can say at the end that the furniture related website can help to bloom and develop the business, customers and products.
Tuesday, January 18, 2011
It is expensive to become kind hearted nice man
Now a days government of Bangladesh has taken decision to implement the formula “Food for work”. This is because many of the people newly immigrant to capital city choose the begging as profession to maintain their lively hood.
Being the third world country we are already lays behind in terms of financially. For the reason all other department and business sector is also backwards. But early in the 15th or 16th century Bangladesh and India reason were very rich. From the ancient ages people remain a bit philosophical. They are mostly as like as a priest of temple or disciple of any saint. And to maintain their own life they used to beg from door to door, village to village or to a distance area.
Because of the non social and non business funda, people never saw this profession negatively. The practice remains keep going on and now a days lots of beggar in the street making their lively hood from begging. Their income is not bad at all. They can earn more than any new/provision/internee officer. But this is making trouble and getting a headache of general people. Often we lack of worker and barrier to making of specialist worker. There are both positive and negative sides of this profession. So let the social father’s deicide weather it should continue or not.
Wise man was always had a large mind. He was a great and kind hearted man. But being that great his family decided to find a bride for him. It was the age for marriage and his family decided that an arranged marriage should they look for. Wise man was new in capital and doing a new job. So he gave the responsibility to his family for the wedding. They will find bride for him and arrange all other program me of wedding ceremony.
As wise man was very great it was natural that he would help some poor people around him. I am talking about a boy who used to beg in front of a café near to his office. Wise man used to give 500 taka starting each month. But after getting marriage wise man had to cut the budget for the lad he used to give 500 bucks. Now he started to give the boy only 250 bucks. After 3 years wise man had a kid. Now he stops giving the lad money.
The poor lad catches wise man at bus stop. The 300 bucks is also a lot for him. The lad asked wise man “What happen to you? Why you stop giving money to me?”
Wise man got understands his feelings. All knew wise man had a great mind. He replied the boy” My son I have a kid now. So it is getting hard for me to give you 300 bucks per month. I have to feed my kid. So, I had to cut your budget now. But I am sorry about the situation. You can come my home some times and can have meal with us”.
The lad said,”Forget about the meal. First you answer me how much you spend my money till now to your wife and kid?”
Although wise man again made the budget and started giving money to the lad.
But I was thinking any way it is always expensive to become kind hearted nice man. Only a rich can be kind and nice person.
Being the third world country we are already lays behind in terms of financially. For the reason all other department and business sector is also backwards. But early in the 15th or 16th century Bangladesh and India reason were very rich. From the ancient ages people remain a bit philosophical. They are mostly as like as a priest of temple or disciple of any saint. And to maintain their own life they used to beg from door to door, village to village or to a distance area.
Because of the non social and non business funda, people never saw this profession negatively. The practice remains keep going on and now a days lots of beggar in the street making their lively hood from begging. Their income is not bad at all. They can earn more than any new/provision/internee officer. But this is making trouble and getting a headache of general people. Often we lack of worker and barrier to making of specialist worker. There are both positive and negative sides of this profession. So let the social father’s deicide weather it should continue or not.
Wise man was always had a large mind. He was a great and kind hearted man. But being that great his family decided to find a bride for him. It was the age for marriage and his family decided that an arranged marriage should they look for. Wise man was new in capital and doing a new job. So he gave the responsibility to his family for the wedding. They will find bride for him and arrange all other program me of wedding ceremony.
As wise man was very great it was natural that he would help some poor people around him. I am talking about a boy who used to beg in front of a café near to his office. Wise man used to give 500 taka starting each month. But after getting marriage wise man had to cut the budget for the lad he used to give 500 bucks. Now he started to give the boy only 250 bucks. After 3 years wise man had a kid. Now he stops giving the lad money.
The poor lad catches wise man at bus stop. The 300 bucks is also a lot for him. The lad asked wise man “What happen to you? Why you stop giving money to me?”
Wise man got understands his feelings. All knew wise man had a great mind. He replied the boy” My son I have a kid now. So it is getting hard for me to give you 300 bucks per month. I have to feed my kid. So, I had to cut your budget now. But I am sorry about the situation. You can come my home some times and can have meal with us”.
The lad said,”Forget about the meal. First you answer me how much you spend my money till now to your wife and kid?”
Although wise man again made the budget and started giving money to the lad.
But I was thinking any way it is always expensive to become kind hearted nice man. Only a rich can be kind and nice person.
Monday, January 17, 2011
Wise man in HENI
Wise man asked Ibrahim, “Why people want to be sad/sorry and unhappy?” Ibrahim had stared at wise man face hold his sight for few seconds then he looked at ground.
“He started thinking”; thought wise man. Now wise man also making list what Ibrahim can think now. He was making guesses and tried to make the list of accurate thoughts of Ibrahim. Wise man started making the sequences and possibility of the probable thought lists of Ibrahim also.
Wise man guessed:
1. Ibrahim is judging Wiseman. More accurate to say Ibrahim is trying to estimate wise man’s question.
After a few seconds nearly about a minute Ibrahim again looked at wise man’s face. Then Ibrahim again looked at ground.
Wiseman guessed again:
2. Ibrahim was trying to make the category of the question. Most probably he wanted to know weather it is a fun or wise man is serious.
Again Ibrahim looked up and his view went to the distance far from the position he was seating. There was an infinite thing in his view. And most possibly about his own sorrows and life. People of Bangladesh is very emotional. They love emotions and often they call their own bad luck. Wise man was also in that group. But one thing was most common among people that they love them selves very much. This was a thing that can motivate the people for their own progress. There is another thing common in people of the Bangladesh, people have EGO also. Although some people see EGO and emotion in negative way. They think that to get progress these 2 things have to remove from the human character.
Any way looking at Ibrahim wise man said ;”Ibrahim, OK no problem you do not have to answer it right now. I will come again to HENI again with is few days. You can answer to it then.”
Actually wise man knew he did not ask the question to get the answer. Actually the thing was that Ibrahim is a very talented GUY and got frustrated of waiting. He was waiting to change his own luck, his family luck. He wanted to get financially sound. He wanted to take his mother and his wife to tour around the world. But those remain dream to him yet. Now-a-days he bought an auto rickshaw and leading his life. Ibrahim is a very good singer of emotional song. In any local social, family, cultural and events he presents his songs But one thing is very good about Ibrahim is that he was very loyal to the people to whom he has to be.
Wise man noted some point of his not getting success of his life.
Wise man knew that Ibrahim will remember the question and will think about the life again and again whenever he will be alone. After a certain period wise man will make him think the thing, emotion is some thing if you define and apply it in negative way; you will ruin your life.
Some times I found wise man very great also. Oh god!!! thanks a lot; even I mixed great people in my life.
“He started thinking”; thought wise man. Now wise man also making list what Ibrahim can think now. He was making guesses and tried to make the list of accurate thoughts of Ibrahim. Wise man started making the sequences and possibility of the probable thought lists of Ibrahim also.
Wise man guessed:
1. Ibrahim is judging Wiseman. More accurate to say Ibrahim is trying to estimate wise man’s question.
After a few seconds nearly about a minute Ibrahim again looked at wise man’s face. Then Ibrahim again looked at ground.
Wiseman guessed again:
2. Ibrahim was trying to make the category of the question. Most probably he wanted to know weather it is a fun or wise man is serious.
Again Ibrahim looked up and his view went to the distance far from the position he was seating. There was an infinite thing in his view. And most possibly about his own sorrows and life. People of Bangladesh is very emotional. They love emotions and often they call their own bad luck. Wise man was also in that group. But one thing was most common among people that they love them selves very much. This was a thing that can motivate the people for their own progress. There is another thing common in people of the Bangladesh, people have EGO also. Although some people see EGO and emotion in negative way. They think that to get progress these 2 things have to remove from the human character.
Any way looking at Ibrahim wise man said ;”Ibrahim, OK no problem you do not have to answer it right now. I will come again to HENI again with is few days. You can answer to it then.”
Actually wise man knew he did not ask the question to get the answer. Actually the thing was that Ibrahim is a very talented GUY and got frustrated of waiting. He was waiting to change his own luck, his family luck. He wanted to get financially sound. He wanted to take his mother and his wife to tour around the world. But those remain dream to him yet. Now-a-days he bought an auto rickshaw and leading his life. Ibrahim is a very good singer of emotional song. In any local social, family, cultural and events he presents his songs But one thing is very good about Ibrahim is that he was very loyal to the people to whom he has to be.
Wise man noted some point of his not getting success of his life.
Wise man knew that Ibrahim will remember the question and will think about the life again and again whenever he will be alone. After a certain period wise man will make him think the thing, emotion is some thing if you define and apply it in negative way; you will ruin your life.
Some times I found wise man very great also. Oh god!!! thanks a lot; even I mixed great people in my life.
Wednesday, January 12, 2011
Logic is ILLOGICAL
Logical things are acceptable. It’s not written any where but fact is; the matter with illogic is not accepted. This is common on the earth. The fact means logic plus incidence. And if I deduct the logic from fact, it becomes story. Story is good to listen but without the logic it is not acceptable in the society.
Fact is, “A man died by accident. The body is taken to hospital for checking, Doctor gave certificates of death and the dead body is buried. There is some witness who saw the accident by their own eyes”. It’s a fact because there are lots of logic and witness behind it. This whole incidence is containing several facts which are containing logic also. As the accident happen the doctor has to do some thing on it etc.
If I say, “A man died in accident. The sub-human has taken to the work shop; the cyborg certified the body as bad sector, needed a full defragmentation” this is a story because it’s not containing the logic.
So question arise what is logic? Wise man says logic is a set up. That is containing a chain of work set. I asked the wise man how you will describe the setup. Wise man replied set up is the nature. Nature has some particular way of working those are known as setup. Such as human born by two different human. The born grow, work and die. This is a set up. And when nature will not want it will destroy the setup. And I asked again what the chains of work set are. Wise man replied Human gives birth of a kid, human take care and brought up the child. The child grows and gives birth of another kid. These are known as the chain of work.
I asked the wise man is the setup is already been set up?? Wise man replied positively. The set up has been made before the human generation is beginning to grow. Some people respect the super natural power as GOD the Almighty.
I got very impressed with the narration. And logic
Then I begin to think in my way. I think I should not think the thing. Because what I found the logic is not logical either. If there is already been a setup then up on which logic this logic is set up. There should logic. And if Logic is illogical then why should logic required. It is much more logical of being illogical. And people will do the most illogical thing rather doing logical things because it’s human nature not to obey the law and order. IF logic proves to be illogical then every thing will go by their own and the total society will collapse. And I got into very much tension if the society gets collapse then what will happen to the human civilization. And whole night could not sleep because of tension.
In the morning I wake up with a heavy eyes full of sleep and thought. I SHOULD NOT THINK ABOUT THE LOGIC weather it is logical or not logical.
Oh god what will happen to me.
Fact is, “A man died by accident. The body is taken to hospital for checking, Doctor gave certificates of death and the dead body is buried. There is some witness who saw the accident by their own eyes”. It’s a fact because there are lots of logic and witness behind it. This whole incidence is containing several facts which are containing logic also. As the accident happen the doctor has to do some thing on it etc.
If I say, “A man died in accident. The sub-human has taken to the work shop; the cyborg certified the body as bad sector, needed a full defragmentation” this is a story because it’s not containing the logic.
So question arise what is logic? Wise man says logic is a set up. That is containing a chain of work set. I asked the wise man how you will describe the setup. Wise man replied set up is the nature. Nature has some particular way of working those are known as setup. Such as human born by two different human. The born grow, work and die. This is a set up. And when nature will not want it will destroy the setup. And I asked again what the chains of work set are. Wise man replied Human gives birth of a kid, human take care and brought up the child. The child grows and gives birth of another kid. These are known as the chain of work.
I asked the wise man is the setup is already been set up?? Wise man replied positively. The set up has been made before the human generation is beginning to grow. Some people respect the super natural power as GOD the Almighty.
I got very impressed with the narration. And logic
Then I begin to think in my way. I think I should not think the thing. Because what I found the logic is not logical either. If there is already been a setup then up on which logic this logic is set up. There should logic. And if Logic is illogical then why should logic required. It is much more logical of being illogical. And people will do the most illogical thing rather doing logical things because it’s human nature not to obey the law and order. IF logic proves to be illogical then every thing will go by their own and the total society will collapse. And I got into very much tension if the society gets collapse then what will happen to the human civilization. And whole night could not sleep because of tension.
In the morning I wake up with a heavy eyes full of sleep and thought. I SHOULD NOT THINK ABOUT THE LOGIC weather it is logical or not logical.
Oh god what will happen to me.
Tuesday, January 11, 2011
IMPOSSIBLE
Some times I think what is impossible but end with the thought that it is impossible to believe the existence of impossible. But many of the people can say that it is ridicules and impossible. Even they will give some examples of impossible things. Such as can you fly like a bird with wings? Although I use to dream to become a bird. There is a poem in bangle on this. If I translate it the meaning will be nearly “ ….RATHER I WOULD BE A BIRD SAME AS A WILD BIRD…..” Although it is impossible for the time being but who knows how long it will remain impossible. Now a days it is possible to fly by aircraft and rocket. 200 years ago people would say mad if you tell about aircraft. Because it was impossible so possibility of impossible is rarely possible. For the time being the dream remains impossible but in near future the impossible dream gets the shape of fact and become possible. So we have to find out the possible obstacle to the impossible dreams and plan. So if the possible obstacle is removed by possible logical action then the most possible action that can happen is that our object is achieved.
So my opinion if any one has to achieve a sky high/impossible target; we have to plan for the possible obstacle first. When it is possible to find out the possible obstacle then the most impossible target becomes possible. So it is not to determine the job is possible or impossible at first it is to determine the possible obstacle and possible benefit from the job and make a possible logical planning. Then the most possible result is success.
It is also narrated by the wise guy that it is the fool who thinks all that is impossible. But certainly it is possible and not is impossible and possibly it should not be the word impossible in the dictionary.
And all the end I found my self “OH I AM IPOSSIBLE. WHAT I HAVE WRITTEN!!!!!” it’s impossible!!!!!!!!!!!!!!!!
So my opinion if any one has to achieve a sky high/impossible target; we have to plan for the possible obstacle first. When it is possible to find out the possible obstacle then the most impossible target becomes possible. So it is not to determine the job is possible or impossible at first it is to determine the possible obstacle and possible benefit from the job and make a possible logical planning. Then the most possible result is success.
It is also narrated by the wise guy that it is the fool who thinks all that is impossible. But certainly it is possible and not is impossible and possibly it should not be the word impossible in the dictionary.
And all the end I found my self “OH I AM IPOSSIBLE. WHAT I HAVE WRITTEN!!!!!” it’s impossible!!!!!!!!!!!!!!!!
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