I have been off this page for quite sometimes now cause I have been busy with some other tasks. In recent times Power Supply has again become erratic and you sure can bet that a lot of Nigerians are once again calling for the heads of PHCN officials.
My primary focus on this page is to find alternative power schemes, that the average home user can easily secure to have continual power supply. You only need to see how dark the entire landscape appears once it's night time. In fact, I once saw a satellite picture of the World map showing properly illuminated outline of Europe, Asia and America, however the continent of Africa appeared very dark due to a very low luminance level. So I ask, is inadequate power supply one of the reasons for the 'dark continent' tag on Africa?
So how can the average home user in Nigeria for instance get electricity in the face PHCN inability to satisfy local consumptions?
I have previously on this page examined the choice of an Inverter circuit which helps you to generate electricity from batteries. The inverter goes along with a charger and battery cells. One could make locally depending on wattage for as low as N5,000 or import from Asia or America. I have come to discover that one could get good inverters cheaper from Asia than the US & the UK, but you need to really determine the type of applications you need the inverter for and also calculate your loads. (check previous posts for these). I got an inverter price list from China some months back and the lowest price was $37.
Comments are welcomed
Tuesday, November 13, 2007
Friday, November 2, 2007
DO YUO KNOW FUEL CELL ELECTRICITY?
A fuel cell is an electrochemical energy conversion device. A fuel cell converts the chemicals hydrogen and oxygen into water, and in the process it produces electricity.
CellsThe fuel cell will compete with many other energy conversion devices, including the gas turbine in your country's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently.
With a fuel cell, chemicals constantly flow into the cell so it never goes dead -- as long as there is a flow of chemicals into the cell, the electricity flows out of the cell. Most fuel cells in use today use hydrogen and oxygen as the chemicals, unlike batteries. A battery has all of its chemicals stored inside, and it converts those chemicals into electricity too but eventually "goes dead" and you either throw it away or recharge it.
Types of FuelCellsThe fuel cell will compete with many other energy conversion devices, including the gas turbine in your country's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently.
A fuel cell provides a DC (direct current) voltage that can be used to power motors, lights or any number of electrical appliances.
There are several different types of fuel cells, each using a different chemistry. Fuel cells are usually classified by their operating temperature and the type of electrolyte they use. Some types of fuel cells work well for use in stationary power generation plants. Others may be useful for small portable applications or for powering cars. The main types of fuel cells include:
Polymer exchange membrane fuel cell (PEMFC)
The PEMFC has a high power density and a relatively low operating temperature (ranging from 60 to 80 degrees Celsius, or 140 to 176 degrees Fahrenheit). The low operating temperature means that it doesn't take very long for the fuel cell to warm up and begin generating electricity.
Solid oxide fuel cell (SOFC)
These fuel cells are best suited for large-scale stationary power generators that could provide electricity for factories or towns. This type of fuel cell operates at very high temperatures (between 700 and 1,000 degrees Celsius). This high temperature makes reliability a problem, because parts of the fuel cell can break down after cycling on and off repeatedly. However, solid oxide fuel cells are very stable when in continuous use. In fact, the SOFC has demonstrated the longest operating life of any fuel cell under certain operating conditions. The high temperature also has an advantage: the steam produced by the fuel cell can be channeled into turbines to generate more electricity. This process is called co-generation of heat and power (CHP) and it improves the overall efficiency of the system.
Alkaline fuel cell (AFC)
This is one of the oldest designs for fuel cells; the United States space program has used them since the 1960s. The AFC is very susceptible to contamination, so it requires pure hydrogen and oxygen. It is also very expensive, so this type of fuel cell is unlikely to be commercialized.
Molten-carbonate fuel cell (MCFC)
Like the SOFC, these fuel cells are also best suited for large stationary power generators. They operate at 600 degrees Celsius, so they can generate steam that can be used to generate more power. They have a lower operating temperature than solid oxide fuel cells, which means they don't need such exotic materials. This makes the design a little less expensive.
Phosphoric-acid fuel cell (PAFC)
The phosphoric-acid fuel cell has potential for use in small stationary power-generation systems. It operates at a higher temperature than polymer exchange membrane fuel cells, so it has a longer warm-up time. This makes it unsuitable for use in cars.
Direct-methanol fuel cell (DMFC)
Methanol fuel cells are comparable to a PEMFC in regards to operating temperature, but are not as efficient. Also, the DMFC requires a relatively large amount of platinum to act as a catalyst, which makes these fuel cells expensive.
Sunday, October 21, 2007
POWER FROM THE WIND IN INDIA
THE ARTICLE YOU ARE ABOUT TO READ SHOULD OPEN OUR EYES ON ELECTRICITY GENERATION IN AFRICA. INDIANS HAVE RECENTLY BEEN APPOINTED MANAGEMENT CONSULTANTS FOR NIGERIA"S TRANSMISSION COMPANY.
http://www.poweralternatives.com/nc/power_stories/display_news/article/wind-energy-is-growing-in-india/492.html
Wind Energy Is Growing In India
Power generation from wind has emerged as one of the most successful programmes in the renewable energy sector in India, even as this source of power is emerging as an alternative in fast-growing countries like India and China that are avidly seeking new energy sources.With a rapidly growing economy, India’s energy needs are increasing, and are largely met by electricity from oil and coal fired power stations.
Industry analysts say that energy is a major input for overall socio-economic development and renewables are expected to play a key role in accelerating development and sustainable growth in the second half of the current century, accounting then to 50 to 60 per cent of the total global energy supply.
Reports suggest that wind generation is the fastest growing energy source in this decade and is expanding at 25 per cent per year. The industry experts recognises India as a new "Wind Superpower".
Available figures suggest that at the end of April 2007 India had 7113.6 MW of wind generating capacity and is the fourth largest market in the world. There are about a dozen wind pumps of various designs providing water for agriculture, afforestation, and domestic purposes, all scattered over the country. The states of Tamil Nadu, Karnataka, Andhra Pradesh, Gujarat, Rajasthan and Maharashtra lead in the field of wind energy
The growth of power generating capacity in India is today driven largely by increasing energy needs. The short gestation periods for installing wind turbines, and the increasing reliability and performance of wind energy machines has made the sector a favoured choice for capacity addition.
South region Tamil Nadu is the state with most wind generating capacity and western Maharashtra is second only to Tamil Nadu in terms of generating capacity. Suzlon has been heavily involved in the state.
The technical potential that is based on the availability of infrastructure, for example the availability of grid, is estimated to be around 13, 000 MW. In India, the wind resources fall in the low wind regime, the wind power density being in the range of 250 -450 W/m. It may be noted that this potential estimation is based on certain assumptions.
With ongoing resource assessment efforts, extension of grid, improvement in the wind turbine technology, and sophisticated techniques for the wind farm designing, the gross as well as the technical potential would increase in the future.
The leading countries in wind power installation are Germany, Spain, the USA, India, and Denmark. India has overtaken Denmark and is the fourth largest wind market in the world.
Wind turbines offered in India range from 250 kW to 2 MW capacities. Currently, there are 7 manufacturers of wind turbine generators in India.
According to a recent study from Emerging Energy Research (EER) entitled Asia-Pacific Wind Power Markets and Strategies 2006-2015, Asia-Pacific is emerging as the new frontier of the global wind industry, with the region expected to add over 46,000 MW of wind power in the coming decade.
In fact, the region’s market leaders - China and India - are expected to add over 41,000 MW between them by 2015. Together they will represent over 80 per cent of the Asian wind market during the period. Japan and Australia will each add between 150 MW and 450 MW per year, followed by less developed markets in South Korea, New Zealand, Taiwan, Pakistan and the Philippines.
Report further says that after a good year in 2006 in which around 1800 MW was added, India will retain its position as Asia’s leading wind power market in terms of total megawatts installed until 2015, when it will be overtaken by China.
Wind is a significant source of electricity in Denmark, Spain and Germany. Denmark generates 14% of its total electricity from wind sources, Spain 9% and Germany 5%. Among developing countries, wind was an important source of electricity in India, contributing around 1% to total electricity generation. Globally, wind generated electricity is still less than 1% of total electricity generation.
By T C Malhotrahttp://www.poweralternatives.com/nc/power_stories/display_news/article/wind-energy-is-growing-in-india/492.html
Sunday, October 14, 2007
UNDERSTANDING SOLAR ELECTRICITY
HI,
I AM SORRY I HAVE BEEN OFF THIS PAGE FOR QUITE SOMETIME NOW, BUT I CAN ASSURE YOU I AM BACK TO SERVE YOU BETTER, BECAUSE I STRONGLY BELIEVE IT'S HIGH TIME AFRICANS FIND WAYS OUT OF THE POWER SUPPLY DEBACLE THAT HAS TRULY KEPT THE CONTINENT DARK. SO I AM CONTINUING WITH ELECTRICITY FROM THE SUN. ENJOY READING AND PLEASE BE FREE TO POST YOUR COMMENTS
Energy from the sun for thousands of years has been harnessed for several purposes. However it is vital that we see this energy in three forms and properly understands the separate applications.
MODE OF OPERATION
Photovoltaic systems through cells convert solar radiation intoelectricity. The PV cell consists of one or two layers of a semiconductingmaterial, usually silicon. When light shines on the
cell an electric field is formed across the layers, hence electricity flows. The flow of electricity is detemined by the light intensity
There are three main types of solar cells viz
• Monocrystalline: made from thin slices cut from a single crystal of silicon. This has a typical efficiency of
15 per cent.
• Polycrystalline: made from thin slices cut from a block of silicon crystals. This has a typical efficiency of around12 per cent.
• Thin Film: made from a very thin layer of semiconductor atoms deposited on a glass or metal base. This has a typical efficiency of 7 per cent.
The PV cells are connected together to form a module. Modules are then linked and sized to meet a particular load (electrical energy demand). The result is a PV array which supplies power to the building it is fitted on. If the building has mains electricity, any excess electricity can be exported to the national grid (as is the case in the US and some parts of Europe).
Alternatively, when demand is high, extra electricity can be purchased from the national grid through the utility companies in addition to the PV electricity. In the event of a mains power failure, PV arrays can be
used to charge batteries.
PV arrays are in a variety of shapes and colours,ranging from grey 'solar tiles' that look like roof tiles, to
panels and transparent cells that you can use onconservatories and glass to provide shading as well as
generating electricity.
I AM SORRY I HAVE BEEN OFF THIS PAGE FOR QUITE SOMETIME NOW, BUT I CAN ASSURE YOU I AM BACK TO SERVE YOU BETTER, BECAUSE I STRONGLY BELIEVE IT'S HIGH TIME AFRICANS FIND WAYS OUT OF THE POWER SUPPLY DEBACLE THAT HAS TRULY KEPT THE CONTINENT DARK. SO I AM CONTINUING WITH ELECTRICITY FROM THE SUN. ENJOY READING AND PLEASE BE FREE TO POST YOUR COMMENTS
Energy from the sun for thousands of years has been harnessed for several purposes. However it is vital that we see this energy in three forms and properly understands the separate applications.
- Solar energy as passive heat: This we receive from the sun naturally and is taken into account in the design of buildings so that less additional heating is required.
- Solar thermal energy: Where the sun's heat provideshot water for homes or swimming pools.
- Photovoltaics (PV): where energy from the sun is employed to createelectricity which runs appliances and lighting.
MODE OF OPERATION
Photovoltaic systems through cells convert solar radiation intoelectricity. The PV cell consists of one or two layers of a semiconductingmaterial, usually silicon. When light shines on the
cell an electric field is formed across the layers, hence electricity flows. The flow of electricity is detemined by the light intensity
There are three main types of solar cells viz
• Monocrystalline: made from thin slices cut from a single crystal of silicon. This has a typical efficiency of
15 per cent.
• Polycrystalline: made from thin slices cut from a block of silicon crystals. This has a typical efficiency of around12 per cent.
• Thin Film: made from a very thin layer of semiconductor atoms deposited on a glass or metal base. This has a typical efficiency of 7 per cent.
The PV cells are connected together to form a module. Modules are then linked and sized to meet a particular load (electrical energy demand). The result is a PV array which supplies power to the building it is fitted on. If the building has mains electricity, any excess electricity can be exported to the national grid (as is the case in the US and some parts of Europe).
Alternatively, when demand is high, extra electricity can be purchased from the national grid through the utility companies in addition to the PV electricity. In the event of a mains power failure, PV arrays can be
used to charge batteries.
PV arrays are in a variety of shapes and colours,ranging from grey 'solar tiles' that look like roof tiles, to
panels and transparent cells that you can use onconservatories and glass to provide shading as well as
generating electricity.
Sunday, September 16, 2007
BEFORE YOU BUY THAT GENERATOR, READ THIS!
Electric Generator's Basic Principles!
Going shopping for an electric generator can be a daunting task for many people. Everyone
Seems to have their own ideas as to what is the best type of electric generator to buy. There are an enormous amount of makes and models now available, all vying for your money with
attractive colors, housings and price tags. Considering that for a large number of people the
electric generator is going to provide emergency or stand-by power, it is important to walk away from the deal with confidence and peace of mind that the correct decision has been made.
These are key factors that you must consider, which will help simplify the selection process.
1. How much electric power do you require? This of course is where you start from. There is no point in going out and purchasing an electric generator and hope that it is going to produce enough power for all your needs. Although you would be surprised at how many people do exactly that. First you need to determine which electrical devices you need to run and then add up the number of watts hat are required to run them - this will be shown either on manufacturer's labels or accompanying manuals. You also need to determine if they have a starting wattage requirement, such as a refrigerator. If they do, then use this reading instead. Once you have added all these together this will be the minimum wattage your electric generator will need to produce. It is always a good idea to add an extra 20 - 25% to give you some extra leeway
2. Diesel, gasoline, LP or natural gas? There are an enormous amount of gasoline electric generators on the market now which offer great warranties and are perfectly suited for small business, recreation, and emergency use. One thing that should be remembered with them is that they are not usually designed to work for long periods of time under load. If this is what you require of your electric generator then diesel would be a far better option. It is worth considering a diesel electric generator if you are looking for a prime power source. These are more fuel efficient and dependable.
3. Brand name? Recognized brand names which have a good reputation are best. You will have easy access to service centers, support and parts. Yamaha, Honda and Briggs and Stratton are well named brands who produce many different models of electric generator.
4. Emergency shutdown? There are some features that are very desirable on an electric generator which can mean the difference between a seized engine to one that has automatically shut itself down. Low oil shutdown is one of the most important ones and it is activated when the oil level drops below a safe operating level.
Times have changed and more and more people are finding that the electric generator brings them security, convenience and much peace of mind.
Courtesy- indieselgenerators.com
Going shopping for an electric generator can be a daunting task for many people. Everyone
Seems to have their own ideas as to what is the best type of electric generator to buy. There are an enormous amount of makes and models now available, all vying for your money with
attractive colors, housings and price tags. Considering that for a large number of people the
electric generator is going to provide emergency or stand-by power, it is important to walk away from the deal with confidence and peace of mind that the correct decision has been made.
These are key factors that you must consider, which will help simplify the selection process.
1. How much electric power do you require? This of course is where you start from. There is no point in going out and purchasing an electric generator and hope that it is going to produce enough power for all your needs. Although you would be surprised at how many people do exactly that. First you need to determine which electrical devices you need to run and then add up the number of watts hat are required to run them - this will be shown either on manufacturer's labels or accompanying manuals. You also need to determine if they have a starting wattage requirement, such as a refrigerator. If they do, then use this reading instead. Once you have added all these together this will be the minimum wattage your electric generator will need to produce. It is always a good idea to add an extra 20 - 25% to give you some extra leeway
2. Diesel, gasoline, LP or natural gas? There are an enormous amount of gasoline electric generators on the market now which offer great warranties and are perfectly suited for small business, recreation, and emergency use. One thing that should be remembered with them is that they are not usually designed to work for long periods of time under load. If this is what you require of your electric generator then diesel would be a far better option. It is worth considering a diesel electric generator if you are looking for a prime power source. These are more fuel efficient and dependable.
3. Brand name? Recognized brand names which have a good reputation are best. You will have easy access to service centers, support and parts. Yamaha, Honda and Briggs and Stratton are well named brands who produce many different models of electric generator.
4. Emergency shutdown? There are some features that are very desirable on an electric generator which can mean the difference between a seized engine to one that has automatically shut itself down. Low oil shutdown is one of the most important ones and it is activated when the oil level drops below a safe operating level.
Times have changed and more and more people are finding that the electric generator brings them security, convenience and much peace of mind.
Courtesy- indieselgenerators.com
SOLAR ELECTRICITY
HAVE YOU EVER THOUGHT ABOUT SOLAR ELECTRICITY, THAT IS, ELECTRICITY FROM THE SUN?
IN AFRICA THESE IS NOT PREDOMINANT DESPITE THE AVAILABLE AND ABUNDANT SOLAR RESOURCES, BUT SOLAR ELECTRICITY IS A VIABLE ALTERNATIVE TO CONVENTIONAL POWER SUPPLY.
HOW DO WE GET SOLAR ELECTRICITY?-
Using solar power to produce electricity is not the same as using solar to produce heat. Solar thermal principles are applied to produce hot fluids or air. Photovoltaic principles are used to produce electricity.
A solar panel (PV panel) is made of the natural element, silicon, which becomes charged electrically when subjected to sun light.
Solar panels are directed at solar south in the northern hemisphere and solar north in the southern hemisphere (these are slightly different than magnetic compass north-south directions) at an angle dictated by the geographic location and latitude of where they are to be installed.
This electrical charge is consolidated in the PV panel and directed to the output terminals to produce low voltage (Direct Current) - usually 6 to 24 volts. The most common output is intended for nominal 12volts, with an effective output usually up to 17 volts. A 12 volt nominal output is the reference voltage, but the operating voltage can be 17 volts or higher much like your car alternator charges your 12 volt battery at well over 12 volts. So there's a difference between the reference voltage and the actual operating voltage.
Let’s consider some fallacies about the solar cells
1. PV is too costly and will never compete with "the big boys" of power generation. Besides, you can never get the energy out that it takes to produce the system.
The cost of producing PV modules, in constant dollars, has fallen from as much as $50 per peak watt in 1980 to as little as $3 per peak watt today. This causes PV electricity costs to drop 15¢-25¢ per kilowatt hour (kWh), which is competitive in many applications
2. Solar electricity cannot serve any significant fraction of world electricity needs.
PV technology can meet electricity demand on any scale. The solar energy resource in a 100-mile-square area of Nevada could supply the United States with all its electricity (about 800 gigawatts) using modestly efficient (10%) commercial PV modules.
3. Solar electricity can do everything — right now!
No way. Solar electricity will eventually become a major player in the world's energy portfolio. The industry just doesn't have the capacity to meet all demands right now. But assuming that the proper investments are made now and are sustained, the industry will become significant in the next few decades.
4. Photovoltaic is a polluting industry.
The PV industry is neither "squeaky clean" nor a major environmental, safety, or health problem. When it comes to emissions, PV's electricity-generating portion of the fuel cycle is the clear winner versus fossil fuel sources.
Watch out for more details in subsequent posts, but if you need more details, please contact me. I would be showcasing some inverters in the maeket shortly and the price ranges. I will also be comming up with some special packages on inverters and others very soon.
IN AFRICA THESE IS NOT PREDOMINANT DESPITE THE AVAILABLE AND ABUNDANT SOLAR RESOURCES, BUT SOLAR ELECTRICITY IS A VIABLE ALTERNATIVE TO CONVENTIONAL POWER SUPPLY.
HOW DO WE GET SOLAR ELECTRICITY?-
Using solar power to produce electricity is not the same as using solar to produce heat. Solar thermal principles are applied to produce hot fluids or air. Photovoltaic principles are used to produce electricity.
A solar panel (PV panel) is made of the natural element, silicon, which becomes charged electrically when subjected to sun light.
Solar panels are directed at solar south in the northern hemisphere and solar north in the southern hemisphere (these are slightly different than magnetic compass north-south directions) at an angle dictated by the geographic location and latitude of where they are to be installed.
This electrical charge is consolidated in the PV panel and directed to the output terminals to produce low voltage (Direct Current) - usually 6 to 24 volts. The most common output is intended for nominal 12volts, with an effective output usually up to 17 volts. A 12 volt nominal output is the reference voltage, but the operating voltage can be 17 volts or higher much like your car alternator charges your 12 volt battery at well over 12 volts. So there's a difference between the reference voltage and the actual operating voltage.
Let’s consider some fallacies about the solar cells
1. PV is too costly and will never compete with "the big boys" of power generation. Besides, you can never get the energy out that it takes to produce the system.
The cost of producing PV modules, in constant dollars, has fallen from as much as $50 per peak watt in 1980 to as little as $3 per peak watt today. This causes PV electricity costs to drop 15¢-25¢ per kilowatt hour (kWh), which is competitive in many applications
2. Solar electricity cannot serve any significant fraction of world electricity needs.
PV technology can meet electricity demand on any scale. The solar energy resource in a 100-mile-square area of Nevada could supply the United States with all its electricity (about 800 gigawatts) using modestly efficient (10%) commercial PV modules.
3. Solar electricity can do everything — right now!
No way. Solar electricity will eventually become a major player in the world's energy portfolio. The industry just doesn't have the capacity to meet all demands right now. But assuming that the proper investments are made now and are sustained, the industry will become significant in the next few decades.
4. Photovoltaic is a polluting industry.
The PV industry is neither "squeaky clean" nor a major environmental, safety, or health problem. When it comes to emissions, PV's electricity-generating portion of the fuel cycle is the clear winner versus fossil fuel sources.
Watch out for more details in subsequent posts, but if you need more details, please contact me. I would be showcasing some inverters in the maeket shortly and the price ranges. I will also be comming up with some special packages on inverters and others very soon.
YOUR INVERTER'S BATTERY
We can not really talk about the inverter without talking about the battery which powers it (though in some application we shall be seeing later, this may not be necessary). Here are tips you need to know about the battery
HOW LONG CAN MY BATTERY POWER THE INVERTER?
As how long as you want your load to run? The load to be supported by the inverter can be determined. After this is known, specific calculations can be made to determine the proper battery bank size.
WHAT TYPES OF BATTERIES ARE APPROPRIATE FOR MY INVERTERS?
There are two principal types of batteries: starting and deep-discharge. Batteries can be either sealed or non-sealed (vented).
Deep discharge types
The battery types recommended for use in an inverter system are: Flooded Lead Acid
(FLA), Sealed Gel Cells (GEL), Sealed Absorbed Glass Mat (AGM); and alkaline types
such as Nickel-iron (NiFe) and Nickel-Cadmium (NiCad).
Starting Automotive (starting) batteries
Are designed to provide high starting current for short periods of time and are not appropriate for inverter applications.
Deep-cycle Flooded Lead Acid (FLA)
Description- A flooded lead acid battery is designed to be deep-discharged before being recharged, making it suitable for inverter applications. Flooded batteries require periodic maintenance consisting mainly of adding distilled water to the cells.
Sealed Batteries (Gel and AGM)
Description- Gel Cell and Absorbed Glass Mat (AGM) batteries are sealed and do not require the addition of distilled water. Since these batteries are valve regulated, over-charging can
cause irreversible damage.
NiCad and NiFe Batteries
These types of batteries can be used but may not be the best for your inverter for the
following reasons:
• Alkaline batteries, such as NiCad and NiFe types, have a nominal cell voltage of 1.2
volts per cell, whereas most inverters and battery chargers are optimized for use with lead acid
batteries having a nominal 2.0 volts per cell (that is, 12 cells for a 24-volt system and
24 cells for a 48-volt system).
• Alkaline batteries require a higher charge voltage to fully recharge, and drop to a
lower voltage during discharge compared to a similarly sized lead-acid type battery.
Battery Capacity Ratings
Amp-hour capacity-
Every deep cycle battery has a capacity which is measured in amp hours. Amp hours are a measure of current flow over time. An amp-hour figure is derived simply by multiplying
current (amperes) by the amount of time the current flows (hours) andare frequently referred to by the abbreviations A-h
As how long as you want your load to run? The load to be supported by the inverter can be determined. After this is known, specific calculations can be made to determine the proper battery bank size.
WHAT TYPES OF BATTERIES ARE APPROPRIATE FOR MY INVERTERS?
There are two principal types of batteries: starting and deep-discharge. Batteries can be either sealed or non-sealed (vented).
Deep discharge types
The battery types recommended for use in an inverter system are: Flooded Lead Acid
(FLA), Sealed Gel Cells (GEL), Sealed Absorbed Glass Mat (AGM); and alkaline types
such as Nickel-iron (NiFe) and Nickel-Cadmium (NiCad).
Starting Automotive (starting) batteries
Are designed to provide high starting current for short periods of time and are not appropriate for inverter applications.
Deep-cycle Flooded Lead Acid (FLA)
Description- A flooded lead acid battery is designed to be deep-discharged before being recharged, making it suitable for inverter applications. Flooded batteries require periodic maintenance consisting mainly of adding distilled water to the cells.
Sealed Batteries (Gel and AGM)
Description- Gel Cell and Absorbed Glass Mat (AGM) batteries are sealed and do not require the addition of distilled water. Since these batteries are valve regulated, over-charging can
cause irreversible damage.
NiCad and NiFe Batteries
These types of batteries can be used but may not be the best for your inverter for the
following reasons:
• Alkaline batteries, such as NiCad and NiFe types, have a nominal cell voltage of 1.2
volts per cell, whereas most inverters and battery chargers are optimized for use with lead acid
batteries having a nominal 2.0 volts per cell (that is, 12 cells for a 24-volt system and
24 cells for a 48-volt system).
• Alkaline batteries require a higher charge voltage to fully recharge, and drop to a
lower voltage during discharge compared to a similarly sized lead-acid type battery.
Battery Capacity Ratings
Amp-hour capacity-
Every deep cycle battery has a capacity which is measured in amp hours. Amp hours are a measure of current flow over time. An amp-hour figure is derived simply by multiplying
current (amperes) by the amount of time the current flows (hours) andare frequently referred to by the abbreviations A-h
Discharge rate
Deep cycle batteries have their amp-hour rating expressed as "at the x-hour rate". This is
an average rate of current flow that would take x number of hours to discharge the
batteries. Common amp-hour figures are at the 6-hour rate, the 20-hour rate and the 100-
hour rate. A battery is classified as having fewer amp-hours if is being discharged at a
faster rate, such as the 6-hour rate. There is an inevitable amount of heat associated with
the flow of current through a battery. The higher the amount of current, the greater the
amount of heat generated. The heat is energy which is no longer available to the battery to
power loads. Hence, at a higher discharge rate, the batteries effectively have fewer amp
hours available. Generally the 20-hour rate is the most common one.
CCA rating-Starting batteries are rated in CCA (Cold Cranking Amps), or other types of "cranking
amps". This expresses battery capacity in terms of its ability to provide large amounts of
current instantaneously to start an engine. It has no time factor, such as hours, taken into
account. This is one reason that starting batteries are not appropriate for inverter systems.
However, batteries such as marine starting batteries, are rated in both CCA and amp
hours. This type is appropriate.
Running time and size
The battery bank’s size determines the length of time the inverter can supply AC output
power. The larger the bank, the longer the inverter can run and the longer the recharge
time.
Depth of discharge. In general, the battery bank should be designed so the batteries do not discharge more than 50% of their capacity on a regular basis. Discharging up to 80% is acceptable on a limited basis, such as a prolonged utility outage. Totally discharging a battery can reduce its effective life or permanently damage it.
Deep cycle batteries have their amp-hour rating expressed as "at the x-hour rate". This is
an average rate of current flow that would take x number of hours to discharge the
batteries. Common amp-hour figures are at the 6-hour rate, the 20-hour rate and the 100-
hour rate. A battery is classified as having fewer amp-hours if is being discharged at a
faster rate, such as the 6-hour rate. There is an inevitable amount of heat associated with
the flow of current through a battery. The higher the amount of current, the greater the
amount of heat generated. The heat is energy which is no longer available to the battery to
power loads. Hence, at a higher discharge rate, the batteries effectively have fewer amp
hours available. Generally the 20-hour rate is the most common one.
CCA rating-Starting batteries are rated in CCA (Cold Cranking Amps), or other types of "cranking
amps". This expresses battery capacity in terms of its ability to provide large amounts of
current instantaneously to start an engine. It has no time factor, such as hours, taken into
account. This is one reason that starting batteries are not appropriate for inverter systems.
However, batteries such as marine starting batteries, are rated in both CCA and amp
hours. This type is appropriate.
Running time and size
The battery bank’s size determines the length of time the inverter can supply AC output
power. The larger the bank, the longer the inverter can run and the longer the recharge
time.
Depth of discharge. In general, the battery bank should be designed so the batteries do not discharge more than 50% of their capacity on a regular basis. Discharging up to 80% is acceptable on a limited basis, such as a prolonged utility outage. Totally discharging a battery can reduce its effective life or permanently damage it.
Battery Configurations
The battery bank must be wired to match the inverter’s DC input voltage specifications. In
addition, the batteries can be wired to provide additional run time. The various wiring
configurations are:
The battery bank must be wired to match the inverter’s DC input voltage specifications. In
addition, the batteries can be wired to provide additional run time. The various wiring
configurations are:
1. Series Wiring batteries in series increases the total bank output voltage. This voltage MUST
match the DC requirements of the inverter or inverter and/or battery damage may occur.
2. Parallel Wiring the batteries in parallel increases the total run time the batteries can operate the AC loads. The more batteries connected in parallel the longer the loads can be powered from
the inverter.
3. Series-Parallel Series-parallel configurations increase both the battery voltage (to match the inverter’s DC requirements) and run-time for operating the AC loads. This voltage must match the DC requirements of the inverter.
match the DC requirements of the inverter or inverter and/or battery damage may occur.
2. Parallel Wiring the batteries in parallel increases the total run time the batteries can operate the AC loads. The more batteries connected in parallel the longer the loads can be powered from
the inverter.
3. Series-Parallel Series-parallel configurations increase both the battery voltage (to match the inverter’s DC requirements) and run-time for operating the AC loads. This voltage must match the DC requirements of the inverter.
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