Brief Information about Maxwell Technologies:
Maxwell Technologies is headquartered in San Diego, USA and for the past 45 years, Maxwell has been a global leader in developing, manufacturing, and marketing in energy storage and power delivery solutions. The current president and chief executive officer is David J. Schramm and the senior vice president is John J. Warwick. Have you ever bought 48v lithium battery pack
? Together and with a group other individuals, they lead the company in being industry leaders in the following markets:
Automotive
Heavy Transportation
Renewable Energy
Backup power
Wireless communications
Industrial & Consumer Electronics
Reliable Products at Value Driven Prices:
The company is able to provide solutions to their customers that offer superior performance, reliability, and value, backed by extraordinary application engineering and field support. Maxwell Technologies offers its customers the following product lines:
Ultra capacitors- Ultra capacitors are devices that are used in multiple applications such as hybrid buses, semi-trucks, hybrid and electric cars, electric trains, aircraft, energy grid, lifting loads, and backup power systems. These devices store and discharge energy very quickly. They complement a primary energy source like an internal combustion engine, fuel cell or battery that cannot repeatedly provide quick bursts of power. They provide green alternative energy. The ultra capacitors product line consists of the following:
PC10 series, HC series, D cell series, K2 series, 16 volt small modules, 16 volt large modules, 48 volt modules, 56 volt UPS modules, 75 volt power modules, 125 volt transportation modules, 160 volt modules, and engine start module.
Microelectronics- Maxwell Technologies offers the most up-to-date technical information and resources as they relate to our microelectronic solutions for space. The microelectronics product line consists of the following:
Single board computer for space, amplifiers for space, comparators for space, A to D converters for space, D to A converters for space, memories for space, switches & multiplexers for space, nuclear event detectors for space, and interface logic for space.
High Voltage- High Voltage capacitors are designed and manufactured to perform reliably for decades in all climates. The products for this line are usually used in the life tank and gas insulated switchgear circuit breakers for voltage distribution uniformity, dead tank switchgear circuit breakers for increasing the breaking power, generator breakers of power plants as well as capacitive voltage transformers for precise voltage measurement. The high voltage product line consist of the following:
MV capacitors & dividers, grading capacitors, coupling capacitors, GIS capacitors, capacitive voltage dividers, and specialty capacitors.
Maxwell Technologies Advantages:
Maxwell Technologies has provided reliable energy with an environmental focus. On November 10, 2013, Maxwell Technologies announced that their super capacitors are currently being used in Chinese hybrid buses. With the use of the capacitors, the buses will decrease the weight of the car and extend the range, making the buses overall more efficient. Look to Maxwell Technologies for more significant developments in the near future such as the one mentioned above.
Get more info at: 2v lead acid battery
2014年12月30日星期二
2014年12月29日星期一
Installing Solar Panels: What's the Difference Between Grid-Tied and Battery Energy Storage Systems?
When you decide to go the solar route, figuring out how you're going to store energy for use in times when there isn't enough sunlight to meet your power needs is one of the biggest elements to consider. Your solar panel installer can talk you through the different energy storage options that are available to you.
Together, you can decide what's best for your situation. However, going in to that conversation armed with a basic knowledge of the two basic setups--grid-tied versus battery solar panel systems--will ensure that you and your solar expert are on the same page, and that you make the best-informed decision possible.
A grid-tied solar panel system is, as it sounds like, connected to the general power grid. Because the sun is such a bountiful resource, it's quite possible that, at times, your solar panels will create more power than you can use. With a grid-tied system, that excess power is converted to AC current via a grid-tie inverter and then is essentially sold to the power company to be used elsewhere.
A metering program records how much of your power goes through this process, and you are credited that amount against your monthly electricity bill. On days when there isn't enough sun shining, you'll also be able to draw power from the grid to keep your lights on and your appliances running. A grid-tied solar power installation is great if you are using a combination of solar energy and traditionally generated electricity to power your home.
The other commonly used option for how your solar energy is stored is a battery-based system. This is a closed system that is not connected to the power grid. Instead of excess power getting converted into electricity and being sold to the power company, that converted electricity is stored in rechargeable batteries. One of the main benefits of the battery model is that it puts you in total control of your power. You can use the stored electricity whenever you need it, particularly at night or on days when the sun isn't shining, and at no additional cost. If you decided to install solar panels in order to use solar energy as your primary power source, battery storage is an excellent option.
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Together, you can decide what's best for your situation. However, going in to that conversation armed with a basic knowledge of the two basic setups--grid-tied versus battery solar panel systems--will ensure that you and your solar expert are on the same page, and that you make the best-informed decision possible.
A grid-tied solar panel system is, as it sounds like, connected to the general power grid. Because the sun is such a bountiful resource, it's quite possible that, at times, your solar panels will create more power than you can use. With a grid-tied system, that excess power is converted to AC current via a grid-tie inverter and then is essentially sold to the power company to be used elsewhere.
A metering program records how much of your power goes through this process, and you are credited that amount against your monthly electricity bill. On days when there isn't enough sun shining, you'll also be able to draw power from the grid to keep your lights on and your appliances running. A grid-tied solar power installation is great if you are using a combination of solar energy and traditionally generated electricity to power your home.
The other commonly used option for how your solar energy is stored is a battery-based system. This is a closed system that is not connected to the power grid. Instead of excess power getting converted into electricity and being sold to the power company, that converted electricity is stored in rechargeable batteries. One of the main benefits of the battery model is that it puts you in total control of your power. You can use the stored electricity whenever you need it, particularly at night or on days when the sun isn't shining, and at no additional cost. If you decided to install solar panels in order to use solar energy as your primary power source, battery storage is an excellent option.
For More Information Visit: 10KW UPS
2014年12月25日星期四
The Economic Goldmine of Energy Storage
photo by: 12v 33ah battery
The concepts of solar, wind, and even water energy as a renewable power sources are not new by any stretch of the imagination. The sticking point for all of them has always been the same: the most reliable and economic way to store energy for later demand usage. The sun beats down during the day giving heat and light; there is less demand for electricity for lights and other items during the day when we are away from home at jobs and at school.
When we come home however, we like to have lights so that we do not bump into the furniture in the dark, and we like to be able to turn on the television for entertainment. Unfortunately, we do not have the sun to give us solar power at night; this means that we must be able to store that energy during the daytime to use when the sun has gone down. After all, no one has developed lunar power.
The best method for efficient, cost effective solar energy storage may be to store the heat in a solar thermal plant instead of storing the energy from the sun's rays in a battery. A solar thermal plant creates energy by "boiling water into steam and spinning a turbine" (Wald 2008). By harnessing and storing this power, the owner of a solar thermal plant could then sell this power.
New methods of building the best and most profitable energy storage systems are being explored every day. One method that looks hopeful is the salt tank system. "Molten salt can reach extremely high temperatures without reaching high pressure" (Wald 2008). This means that the salt can be stored in a tank and heated as much or as often as needed without the fear of it building enough pressure to expand, breach, or burst the holding tank.
There are some drawbacks to the use of a thermal solar plant. The molten salt system can be housed in a tower, which is limited only by the size of the actual tower. Another system stores the salt in pipes which must be warmed constantly or the salt settles and becomes solid, clogging the pipes.
A photovoltaic plant can lose its power on cloudy or rainy days. This is a big concern in some areas, not as big in others. The amount of power that can be lost will vary but it can be enough to cause an energy provider some deep concern.
2014年12月24日星期三
Large - Scale Wind Turbines: Grid Management and Energy Storage: The Facts and Factors of Wind Power
Grid management, predictability, and energy storage are a few of the most important, most key elements in determining how to execute the instillation of efficient energy generation by wind power equipment. There are possibilities for temporary loss of profit in such a proposition - but the more technology that goes into the generation of wind power the more likely this is not to occur. Do you need solar charge controller 48v ? When you want to have the most effective large - scale wind turbines possible there are details that those who design such wind turbines must seriously consider.
Details such as Grid management, Predictability, and Energy Storage are very important. However, there have been negative effects due to intermittency, or the idea of pouring money into wind power generation, which put the idea into question. There are several considerations as to which kind of alternative power source will best suit your needs. Wind power could be the answer for you. But there are also other options to explore -- wind farms have been very effective, and so have smaller wind turbines, under certain conditions.
1. Grid Systems:
o There are specific grid systems responsible for the routine distribution of the amount of energy that wind power equipment can collect.
o The control of wind turbine grid systems or rather, the grid management of these systems is controlled by cycling on certain timescales.
o The most important wind power grid systems of today are those belonging to larger - scale wind turbine farms.
o Many well - designed grid systems have an amazing amount of control over the demands the system requires in order to work properly.
2. Predicting The Wind:
o Many of the critics who are hesitant to allow wind power funding over other alternative sources of energy. This is because of the variability and unpredictability of the wind.
o However, in the case of research and funding for solar power, cloud cover is also an unpredictable factor. Therefore, you can see why there would be such a conflict of interest between the funding of science for researchers on either side.
o I suppose that the real question is what kind of natural energy source can be best predicted, wind, sunlight, or even rain.
3. Storing Wind - Power Energy
o Many supporters of wind power systems note that the tools used to manage the existing issues of the wind's unpredictability.
o There are also arguments that, these tools are among the many advantages of generating wind power already established - and already proven to exist.
The three concerns about wind power addressed in this article are similar, if not the same, as many other concerns. The milestones to overcome brought up in wind power generation as well as the research and development of other kinds of alternative energy are, quite debatably, equally important.
What it is most important to determine is which form or forms of natural energy resources will be the most effective to our overall environmental, economical and scientific goals. Do you know 12v 65ah battery? When you are considering the use of a small - scale type of alternative electrical energy, i.e., a natural solution - perhaps your particular environment will help you decide what to do. And remember, you can (and likely should) consult at least one professional in the process.
2014年12月23日星期二
Solar Power, Photovoltaics, Energy Storage
Photovoltaics are used to convert sunlight into electricity, also the use of lenses or mirrors can be used to concentrate sunlight along with a tracking system to create the sunlight into a small beam. Have you known about 72v lithium battery? Conversion with Photovoltaics is done by the Photoelectric effect. Solar power has great potential, but does not supply much of the world's needs.
There exist many different technologies of photovoltaics, such as polycrystalline silicon and amorphous cells.
It is still unknown which of all the types will be the most favored choice.
Solar cells were limited until the 1970's due to the high cost. Another drawback has been the high cost of installation, which also has been decreasing over the recent years.
CONCENTRATING SOLAR POWER
The lenses or mirrors along with the tracking system are used to focus sunlight into a small beam.
There are several types of mirrors and lenses used, but all are used to heat up fluid, which is used for power generation or storage.
PHOTOVOLTAICS
This solar cell converts the light energy into electric current through the photoelectric effect. Solar cells have been in use since the 1880"s, the early types used selenide in place of copper oxide, which did not convert nearly as much sunlight into electric current. The early cells were not very efficient and very expensive, but led to the research of where we are today.
ENERGY STORAGE
Concentrating solar power is not a type typically used in a home environment, so we will talk about photovoltaic cell storage. Do you know 36v solar charge controller? Rechargeable batteries are the most common source of storage. With the use of a grid tied system the excess electricity can go back to the transmission grid for a credit on what you do not use. Normally the credits roll over from month to month with an annual surplus settlement.
There exist many different technologies of photovoltaics, such as polycrystalline silicon and amorphous cells.
It is still unknown which of all the types will be the most favored choice.
Solar cells were limited until the 1970's due to the high cost. Another drawback has been the high cost of installation, which also has been decreasing over the recent years.
CONCENTRATING SOLAR POWER
The lenses or mirrors along with the tracking system are used to focus sunlight into a small beam.
There are several types of mirrors and lenses used, but all are used to heat up fluid, which is used for power generation or storage.
PHOTOVOLTAICS
This solar cell converts the light energy into electric current through the photoelectric effect. Solar cells have been in use since the 1880"s, the early types used selenide in place of copper oxide, which did not convert nearly as much sunlight into electric current. The early cells were not very efficient and very expensive, but led to the research of where we are today.
ENERGY STORAGE
Concentrating solar power is not a type typically used in a home environment, so we will talk about photovoltaic cell storage. Do you know 36v solar charge controller? Rechargeable batteries are the most common source of storage. With the use of a grid tied system the excess electricity can go back to the transmission grid for a credit on what you do not use. Normally the credits roll over from month to month with an annual surplus settlement.
2014年12月22日星期一
Learn How to Recondition Rechargeable Batteries for Home Uses
If you are looking to start a small business, perhaps one you can operate
from home, and that has potential for growth, then an enterprise that ticks all
of these boxes is battery reconditioning. The reasons for this is that in the
next few years demand for battery storage is going to grow. This is because
home renewable energy like solar, and wind, need somewhere to store power that
they create. This stored power is used if the sun isn't shining, or the wind
isn't blowing.
If you want to learn how to recondition portable storage system, and also
find some top tips on where to get cheap deep cycle batteries, for home
renewable energy storage, then read on.
Usage in home energy projects.
Often the most expensive component of a renewable energy system is the storage
battery bank. This bank will usually comprise of a number of deep cycle
lead-acid batteries. The number of batteries needed will depend on the expected
power usage, but it will be anything from ten upwards. These batteries are not
cheap, and they don't last forever.
So as more and more people "go green," and start producing their
own clean power, you can imagine how much demand their will be for cheap deep
cycle batteries, and also for someone who can recondition existing battery
banks.
What is a deep cycle lead-acid battery?
Deep cycle refers to the fact that this kind of battery is designed to go
from fully charged to almost flat, and produce a steady current all through
this range. Unlike automotive style batteries that are designed to remain
almost fully charged all the time, and produce a high starting current to the
engine.
Free batteries.
Deep cycle batteries are found in golf carts, or wheelchairs, and are used
for marine applications like running electrical equipment in boats. The great
news is that you can probably pick up ones that you can recondition for free,
from golf clubs, or boat yards. This is because once they no longer hold charge
most people just replace them, and consign the old ones to the dump. They will
be only too pleased to let you take them away.
Testing.
Most of the batteries you get this way can be restored. However the first
job is to test them, as a few will prove to be faulty. This test involves
giving them a charge, and using a tool you can make yourself to check each plate
to make sure it is functioning well. Once yours passes this test you can start
the reconditioning process.
Reconditioning.
Reconditioning them involves removing sulfation from the plates, and
replacing or rejuvenating the fluid, (electrolyte.) Substances found in these
kinds of units can be harmful, and so it is important that you take some safety
precautions. Do you need 20KW off grid inverter? Everything you will need however can be found locally, and your
whole kit will cost very little. Your start-up costs will be more than covered
from your first few sales.
As you can see learning how to recondition rechargeable batteries, and
starting a service providing cheap deep cycle batteries for home renewable
energy storage, is one that will be more and more in demand. Plus by giving
these batteries a longer life you keep them out of landfill, so you will be
helping the environment too.
Energy Storage System - Pros and Cons
The development of an adequate, cost effective way to store solar energy cannot come fast enough. Different methods are being used currently, and others are being experimented with and explored. Some home solar energy 12v 150ah battery
users have had great success with their systems, but solar systems may not be appropriate for all areas of the world, nor would they be good on a larger scale. If solar energy is to be the replacement for other less environmentally friendly energy sources, then there must be a way to store it on a larger scale that is still safe and affordable for everyone.
The Cons to Solar Energy Storage
The sun is not entirely predictable or reliable. Clouds can block the sun's rays for seconds, minutes, or even hours causing a storage system to lose megawatts of energy. The loss of megawatts can result in power loss for the users. If the system in place is not big enough to store enough energy for these times, it will not be useful in the long run.
The sun is not a good choice in certain parts of the world where the weather is generally cloudy and overcast. Even in places where there is a lot of sun, days of rain and clouds could shut down a system in a matter of hours.
The salt tank systems are adequate on a small scale. On a larger scale, they could face the same NIMBY protests that other types of energy plants face whenever a new one is proposed.
Solar panel systems can be expensive, especially at start up. A photovoltaic system that is large enough to run an entire household can cost $50,000 -far out of the reach of many budgets in these times.
The Pros to Solar Energy Storage
Solar energy is renewable, non-polluting, and easy to harness for use. A new home that is built with solar panels or an existing home that adds them can qualify for a tax credit or other financial incentives. This makes the concept even more attractive. The current systems for solar energy storage include a photovoltaic system and a molten salt system, but each has drawbacks.
Solar power can be used to offset or replace electrical costs from the utility company. This, in turn, forces the utility company to become more competitive in their pricing. If one family in a neighborhood sets up solar panels and reduces their energy costs by half or more and the utility company increases the rates for the next door neighbors, it is not long before the next door neighbors are going to consider going to solar power as well.
Solar power is safer to use than other energy sources, especially those that rely on coal which must be mined from the earth and then transported around the country, or oil which is expensive and must be obtained from foreign countries. It's important to advocate 20KW off grid inverter . Harnessing the sun's heat may be the easiest way to store the energy for later use in solar thermal systems.
The Cons to Solar Energy Storage
The sun is not entirely predictable or reliable. Clouds can block the sun's rays for seconds, minutes, or even hours causing a storage system to lose megawatts of energy. The loss of megawatts can result in power loss for the users. If the system in place is not big enough to store enough energy for these times, it will not be useful in the long run.
The sun is not a good choice in certain parts of the world where the weather is generally cloudy and overcast. Even in places where there is a lot of sun, days of rain and clouds could shut down a system in a matter of hours.
The salt tank systems are adequate on a small scale. On a larger scale, they could face the same NIMBY protests that other types of energy plants face whenever a new one is proposed.
Solar panel systems can be expensive, especially at start up. A photovoltaic system that is large enough to run an entire household can cost $50,000 -far out of the reach of many budgets in these times.
The Pros to Solar Energy Storage
Solar energy is renewable, non-polluting, and easy to harness for use. A new home that is built with solar panels or an existing home that adds them can qualify for a tax credit or other financial incentives. This makes the concept even more attractive. The current systems for solar energy storage include a photovoltaic system and a molten salt system, but each has drawbacks.
Solar power can be used to offset or replace electrical costs from the utility company. This, in turn, forces the utility company to become more competitive in their pricing. If one family in a neighborhood sets up solar panels and reduces their energy costs by half or more and the utility company increases the rates for the next door neighbors, it is not long before the next door neighbors are going to consider going to solar power as well.
Solar power is safer to use than other energy sources, especially those that rely on coal which must be mined from the earth and then transported around the country, or oil which is expensive and must be obtained from foreign countries. It's important to advocate 20KW off grid inverter . Harnessing the sun's heat may be the easiest way to store the energy for later use in solar thermal systems.
2014年12月21日星期日
Continue Your Green Education Today With Solar PV 103 - Energy Storage
If you have been following the series on Solar PV, then you know that it
has covered power generation thus far. The idea is, in the most simple of
terms: Sun shines, appliances work. This is great, but most of us are not home
during the day to use 10KW UPS
. Is this power wasted? What happens at night
when American Idol airs and there is no sunlight? (I know you will see the
other parents in the school parking lot tomorrow morning; rest assured, you
will be in the loop). The real question is, 'How is this energy stored?'
and Solar PV 103 aims to answer just that.
Energy storage is no simple task. The goal is to answer the following: how
can we use energy available now to power something later on; it is like asking,
how can I cook breakfast, lunch and dinner now so that it will have that fresh
from the oven taste and temperature at meal time?
You probably know the most common way to store energy, batteries, but
there are actually many ways of doing so. One technique is the use of
flywheels. Sparing much of the technical detail, electricity is used to power a
motor which spins very heavy wheels. These wheels remain spinning until
electricity needed, at which point they transfer their spinning force to a
generator to re-create electricity. Another popular choice is the Fuel Cell.
This can get very technical as well, but the basic idea is that energy is used
to store Hydrogen. When the demand for electricity arises, the stored Hydrogen
is combined with Oxygen from air and with the use of a catalyst, a chemical
reaction takes place which produces electricity, heat and water, making it a
very clean solution (storing the Hydrogen is the tricky part).
Clearly these solutions are rather scientific, so what if there were other
ways? Some ideas start by asking the question, 'What will I need this energy
for?' and designing a specific solution for that need. Some buildings in New
York City, for example, take power at night when electricity is quite cheap and
create ice such that during the day, when electricity rates are very high, the
building is cooled by blowing air over these very large ice blocks. It is in
this way that energy available now may be used later.
But there is another idea: the "I'll scratch your back; you scratch
mine" approach. That is, I will give you my readily available power now in
exchange for yours when I need it. This is the crucial idea when thinking about 36v solar charge controller. All day as your system is pumping out electricity, it is
being sent back to the grid for use by other homes and offices that do not have
power sources of their own. The grid knows that you are doing it a favor and
issues you a credit (Your home or office is outfitted with an electric meter
that will actually spin backwards when you are supplying power). Therefore,
at night, when your solar array is dormant, you draw power from the grid
working against this credit. Solar installers have copious data on average
sunlight and can quite accurately size your system such that this day/night
issue, as well as seasonal effects will result in the near-elimination of your
electricity bill.
Of course, solar power does not have to be grid-tied, but going off grid
means additional costs for battery backup, battery maintenance, and the loss of
many financial incentives available to grid-tied systems (topics which will
be discussed in more advanced lessons later).
I hope you have enjoyed this lesson on energy storage; please keep an eye
out for Solar PV 104 - Racking.
2014年12月19日星期五
Living And Working In Sustainable Environments - Energy Storage
There are many types of electrical energy storage; from capacitors,
fly-wheel to rechargeable batteries of various technologies. However, in a
home, office or factory environment only a few are practical or affordable.
On the battery side, as the most practical form of storage, there are some
challenges and trade-offs that have to be considered. For example the cost of battery for electric bike
and their specific performance in terms of charging efficiency,
discharging efficiency and self-depletion performance versus price.
Charging from Solar or Wind will be most economical for a deep depleted 12
Volt flooded lead acid battery (10.7 volts at no load) to about 87% of charge
with an efficiency of ~91%. From 87% to 100% the charging efficiency drops to
55% unless it is charged very slowly which will not be possible for daily
cycles. The initial cost for a Raw Watt hour (R-Wh) for flooded lead
acid batteries is approximately $0.24.. $0.19. The size of the battery capacity
also depends on the way you want to use the battery. There will be two numbers
of importance, the cost per Usable Watt hour (U-Wh) and the expected life
time in cycle days.
The U-Wh are significantly lower than the R-Wh advertised by the
manufacturer and depend on a number of other factors like the general area of
operation between 55% discharge and 13% discharge. When operating in this area
the charging efficiency is maximized to about 91% but the cycle life of a lead
acid battery is greatly reduced and charts from the battery manufacturer have
to be used to determine the realistic cycle life. When used with solar
generation or load-balancing, a cycle day is mostly a day of the year.
If your energy use is lower at the weekends this can extend lead acid battery
life as anti-sulfurization charging can be applied during that period.
Charging Efficiency 91% (at U-Wh 32% of R-Wh)
Battery Type / Expected Cycle-Life (days)
Supermarket Chain Store 12 Volt Car Battery / 300 (less than a year)
Marine Deep Cycle / 400 (little more than a year)
Flooded Sealed Lead Acid (250 Ah/12 Volt) / 900 (2..3 years)
Flooded Managed Lead Acid (1000 Ah/12 Volt) / 1400 (4..5 years)
Supermarket Chain Store 12 Volt Car Battery / 300 (less than a year)
Marine Deep Cycle / 400 (little more than a year)
Flooded Sealed Lead Acid (250 Ah/12 Volt) / 900 (2..3 years)
Flooded Managed Lead Acid (1000 Ah/12 Volt) / 1400 (4..5 years)
When flooded lead acid batteries are used in the area of operation between
90% charged and 70% charged (10% discharged to 30% discharged) the cycle life
is greatly improved but the charging efficiency is not that good unless the
batteries are charged very slowly in which case the charging efficiency can be
improved to about 83%. In this case the battery capacity is derived from the
most efficient charging rate resulting in very large battery banks.
Charging Efficiency 55% (U-Wh 20% or R-Wh)
Battery Type / Expected Cycle-Life (days)
Supermarket Chain Store 12 Volt Car Battery / 350 (less than a year)
Marine Deep Cycle / 450 (more than a year..1.5 years)
Flooded Sealed Lead Acid (250 Ah/12 Volt) / 1000 (5..6 years)
Flooded Managed Lead Acid (1000 Ah/12 Volt) / 1600 (7..10 years)
Supermarket Chain Store 12 Volt Car Battery / 350 (less than a year)
Marine Deep Cycle / 450 (more than a year..1.5 years)
Flooded Sealed Lead Acid (250 Ah/12 Volt) / 1000 (5..6 years)
Flooded Managed Lead Acid (1000 Ah/12 Volt) / 1600 (7..10 years)
Charging Efficiency 95% (U-Wh 70% of R-Wh)
When using LiFePO or also known as Lithium Iron Phosphate
batteries, the charging and discharging efficiency is significantly higher at
around 95% at a higher percentage of U-Wh versus 100% of R-Wh, but the cost can
be 2 to 3 times the cost of flooded lead acid having 2x extended cycle life at
80% of original capacity. Total economics work out to be exactly the same cost
over 10 years as the equivalent flooded lead acid battery system for approximately the same storage and discharge performance. However, the storage
space and weight for the same capacity is heavily in favour of LiFePO
with 1/3-rd of the volume and weight of lead acid batteries, and half the
weight and volume of Ni-Fe batteries. Also, when you start looking at nonideal
conditions (cold, hot, unpredictable charge and depth of discharge), the lead
acid battery performance falls off dramatically and it is worth the current
cost of a LiFePO battery system.
Charging Efficiency 90% (U-Wh 80% of R-Wh)
When space and weight are not so critical a Ni-Fe Battery is a solution,
it requires a storage and operating environment of 0°..45° C (32°..117°F) and
therefore has to operate in-doors or in a crudely climate controlled area or
more sophisticated cooling built into the battery cell. However, charging and
discharging efficiency is high with 90% and the cycle time is in the 3000-plus
cycles giving it a life time of 10 years plus. Ni-Fe batteries have been known
to last 20 years retaining full capacity.
What this means for load-balancing systems based on batteries is
that the cost for the equipment to charge the batteries efficiently as well as
the correct battery size to optimize charging efficiency and life time (time to
replacement) have to be carefully taken into account to determine system sizes
that can produce a payback from load-balancing.
Both systems, flooded lead acid and LiFePO, will benefit from each
cell fully managed by an appropriate charger controller rather than using multi-cell
batteries that do not allow individual cell management or replacement. Ni-Fe
batteries are more forgiving to overcharge and under-charge but require
water-refilling on a regular basis or an automatic system to accomplish their
automatic maintenance.
How often you have to change your batteries or supplement with extra
capacity will affect your ROI or cost per stored and released Watt hour (Wh).
You may decide it is more cost-effective to add 20% new batteries at the end of
the 80% cycle life if your type of battery will continue to lessen its capacity
at the same rate per cycle as it did up to the 80% capacity point. In this case
you have to plan the space required for the extra 20% beforehand. You can then
decommission 20% when the total capacity has reached 80% again and replace with
20% of new batteries and so on.
Disclaimer
In this article no claim is made as to the accuracy of any values, prices or
other information given as they are rough indications or estimations based on
publicly available information and the author's experience.
Tips for Selecting a Battery
Some portable storage unit manufacturers are masters in misrepresenting the true performance of their products.
Some portable storage unit manufacturers are masters in misrepresenting the true performance of their products.
Although a Supermarket Chain Store battery normally has a 1 year
warranty, it has no Amp hour (Ah) nor a Wh rating and would only survive 150
deep discharge to fully charged cycles depleting its capacity to 50% or failing
completely.
Do not use batteries for which you can not obtain cycle life diagrams
showing after how many deep cycles the 80% mark of capacity is reached.
Starting a car or tractor once a day is not a deep cycle, cranking power
and cranking cycles have no relevance in a load balancing application.
A battery made for the
application will have an Ah and or a Wh rating. Be aware that if your
application is mission critical design the capacity taking the 80% of capacity
at end of life into account.
2014年12月18日星期四
What Is the Next Step In Energy Storage and Preventing Inefficiency?
One of the challenges with solar and wind energy and some other
alternative energies is that we don't have access to them all the time. For
instance, hydro-electric electricity in some places may not be available in the
summer months, rather more readily available with the run-off of spring when
the ice melts in the mountains or during the rainy seasons when the water cycle
is doing its main business.
For solar, it's a similar issue, as "The Sun notoriously doesn't
shine at night," and although that sounds hilarious and obvious, I heard
that quote from a Nobel Lariat giving a speech on solar pump
at a local
university in 2011. Wind power is similar in this regard because when the wind
is not blowing you cannot collect energy. If the wind blows more steadily at
night, but humans need the draw down in energy during the day, then we have a
problem don't we?
The answer of course is to find a way to store the energy created and then
use it at a later date. Some ideas have been to pump pressure underground in
giant tanks, which would take the energy being created at the time, and that
pressure would blow out during the day turning an energy generation device. That
could work.
There was an article in Discover Magazine in September of 2012 titled;
"Tornado Tech - Excess Heat from Power Plants or Seawater Could be Twisted
into a Renewable Energy Source," which brings up a very interesting topic
of vortex flows and efficiency of heat engines, propulsion and energy
generation.
Such a scheme obviously makes sense, but what will the next step be in
energy storage? Remember every time we collect energy from one place and
convert it into electricity for something else we lose a little bit of energy,
we never get 100% efficiency. In the case of wind power and then creating
pressure, we lose a little bit of energy in the pumps which pump up the
pressure, and we lose a little bit of energy from the friction of the device which
turns to generate electricity. Not to mention the energy loss from the friction
of the blades turning, and the system itself.
We also lose energy in transmission lines. The trick is to prevent
inefficiency. And as long as were talking about inefficiency, then we need to
be honest with ourselves that when we convert sunlight from solar cells and
energy, they aren't very efficient, in the future they may be, but right now
they are not. We need to work on efficiency, energy storage, and we need to use
the laws of physics without trying to be so politically correct that we fail in
these large projects.
It does no good to set up a very large energy generation system, give out
all sorts of tax credits to help it compete in the free market, when it isn't
as efficient as what we already have producing our green energy storage
. That just wouldn't
be smart business, nor does it stick with the conservation of energy or laws of
physics in this domain. Please consider all this and think on it.
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