How to electricity barrels

[freddau]

Australian engineers have developed an electricity storage process based on the circulation of liquid electrolytes. Main application envisaged: regulating the production of wind turbines.

Located between Australia and Tasmania, King Island does not have the appearance of an island at the gates of the future. However, a large hangar built on its west coast houses an electricity storage system that could revolutionize wind energy.
King Island is not connected to the continental power grid. In addition to its small wind power plant, it has long depended on diesel generators to meet its electricity needs. But things changed in 2003, when the local electricity company installed a huge new generation accumulator, known as a vanadium circulation accumulator. When the wind is blowing hard, wind turbines produce more electricity than people need. The accumulator then stores the excess energy and releases it when the wind weakens. The use of this system has reduced by almost 50% the amount of fuel oil consumed by thermal generators, which also makes it possible to avoid each year the release of more than 2 tonnes of carbon dioxide into the atmosphere.

Wind energy share increased from 12 to 40%

Adapting supply to demand is particularly problematic with renewable energies. The wind does not always blow when it is needed, which forces the electricity companies to plan a conventional power plant for days when there is no wind and for periods of high consumption. This is why an efficient means of storing and redistributing electricity on a large scale would give renewable energies a welcome boost. Various types of accumulators already exist. But, if each technology has its advantages, circulation accumulators seem to meet a wider range of needs: they can store energy for both small generators and large networks, at a competitive price.
Their technology is more complex than that of conventional accumulators. In a lead-acid battery, for example, electricity is stored as chemical energy in the battery itself. In the case of circulating accumulators, two electrolytes [ion-conductive liquids] are used, which do not have the same redox potential (the affinity of electrolytes for electrons) and are contained in external reservoirs to the accumulator. When it is necessary to supply electricity, each of the electrolytes is pumped into half of a tank separated in two by a thin membrane. The difference in redox potential between the two liquids causes an exchange of electrical charges across the membrane, which generates a current which is recovered by electrodes. A current injected by an external energy source, here wind turbines, allows to reverse the electrochemical reaction and to regenerate the electrolytes, which can then be poured back into their tanks.
The origins of the King Island installation date back to the 1980s, when Maria Skyllas-Kazacos, a young Australian chemical engineer, began researching circulation batteries at the University of New South Wales in Sydney. After more than ten years of development, the license to exploit its technique has been granted to a Melbourne company, Pinnacle VRB. It was she who mounted the circulation accumulator on King Island. This works with 70 liters of vanadium sulphate solution stored in large metal tanks, and can supply 000 kilowatts for two hours straight. Since its commissioning, the average share of wind power in the island's network has increased from around 400% to 12%.
The lifespan of accumulators should greatly exceed that of two to three years of a lead-acid battery. Like lead-acid batteries, circulating accumulators restore up to 80% of the electricity used to charge them, but they keep this efficiency for several years. To increase the efficiency of the accumulator during peak periods, it is sufficient to add tanks. The amount of energy it stores can be increased almost endlessly by making larger tanks. It is therefore a technique that makes it possible to design accumulators capable of supplying 1 kilowatt hour (as much as a large automobile battery) as several hundred megawatt hours in a power plant.

Small vanadium circulation accumulators are already available in Japan, where they are used among other things as emergency generators in factories. In the United States, a 2 megawatt-hour accumulator installed in Castle Valley, in southeastern Utah, enabled the local electricity company, PacifiCorp, to respond to increasing demand peaks, without having to increase the capacity of the aging distribution line supplying the area. The technology developed at the University of New South Wales is now applied by VRB Power Systems, of Vancouver, Canada. The company signed a $ 6,3 million [4,8 million euros] contract last year to install a 12-megawatt-hour vanadium accumulator at the Sorne Hill wind power plant in Donegal, Ireland. The objective is to guarantee the supply of wind power and improve the financial situation of the plant. The latter may resell the electricity stored in the grid during peak periods, during which the tariffs are the highest.
The company has commissioned a new production line, which makes it possible to manufacture 2 000-kilowatt batteries each year. The first twelve are currently being tested by the National Research Council of Canada and one of the largest mobile operators in North America, among others. Today, like all new products, circulation accumulators are more expensive than their competitors. But the commissioning of the new production line could well be a game-changer.
In addition, the researchers are continuing their work. Since vanadium sulphate solutions cannot be very concentrated, vanadium circulation batteries store about half the energy of lead-acid batteries. They cannot therefore be used for applications where compactness and lightness are essential. This is why Maria Skyllas-Kazacos and her team are now looking to replace vanadium sulfate with vanadium bromide, at least twice as soluble. The results of their work should be known by 2008.
VRB Power Systems has already tested its accumulators in electric golf carts. Like existing electric vehicles, cars equipped with a circulation accumulator can be recharged by plugging them into an electrical outlet. Maybe even one day we can simply fill their tank with regenerated electrolyte, and the used solution can be recycled.
It doesn't matter whether or not we fill up with vanadium at the pump one day: King Island has proven that circulation accumulators already have a practical role to play, by allowing the energy produced by the wind to continue to spin in the power lines even when there is not a breath of air. You may not even realize that she is there, which is probably the best compliment that can be given to her.

Tim thwaites
New Scientist
http://www.newscientist.com/

http://www.courrierinternational.com/ar ... j_id=70316

[Woodcutter]

Very well, here is which allows to answer a little to the arguments of "wind of Anger" ...

[jean63]

that's a good job .... well done if it works, there's more to install a lot of wind turbines and regulate with this system.

[the Egyptian]

Very informative, a pleasure to read you

[elephant]

super interesting your article, freddau, bravo.

I still believe that the simplest and cheapest way is to make hot water:

I develop my point of view:

1) it is obvious that we cannot count "only on wind power" whose continuity is insufficient

2) it is indeed very interesting for the consumer to free themselves from external suppliers and develop their autonomy to the maximum (and for the states to free themselves from oil suppliers)

3) in a household, the biggest energy costs are heating (25 kW / day and more) and domestic hot water (9 kW / day for 4 people)

4) a 150 liter tank costs 200 to 400 euros depending on the qualities

5) electronic management of the supply of this kind of energy is very simple and will end up becoming very cheap, unlike power electronics (converters)

6) batteries of all types pose end-of-life waste problems, even if they are huge batteries which can be replaced and recycled.

This is why I recommend, in the current state of the available technique to locally generate hot water to relieve the traditional means of energy production

that said, this opinion does not prevent us from looking for solutions ....

[I Citro]

A few years ago, I read that Bordeaux researchers were working on a similar project.
The goal was to design a regenerable electolyte battery.
The interest was to preserve the energy distribution networks We therefore continued to fill up at the service station with a specific filling system which would suck up the discharged electrolyte while filling up with charged electrolyte.
The problem is that any good handyman would also be able to recharge his electrolyte at home, without going to the "TATOL" station and that, neither the public authorities, nor the oil companies want it ...

[zac]

that said, this opinion does not prevent us from looking for solutions ....

Hello

Although not very favorable to wind power, I use a "solution"

In our island there is no recycling of batteries, so the majority ended up in the ravine then in the sea; some are shipped to China supposedly to be recycled there. so with my friend since the batteries at the end of their life are abundant we prefer to restore them and sell them at half the price of the new one (we save 70/100).

considering the stocks that exist it wouldn't be a problem, with political will, to constitute a deposit to fill up by exchange, but there I must stop dreaming

@ + [/ b]

[jean63]

In our island there is no recycling of batteries, so the majority ended up in the ravine then in the sea; some are shipped to China supposedly to be recycled there. so with my friend since the batteries at the end of their life are abundant we prefer to restore them and sell them at half the price of the new one (we save 70/100

What are you doing to restore them? I have 2 to bring to the landfill.

[zac]

What are you doing to restore them? I have 2 to bring to the landfill.

"Normal" battery edta in electrolite + correction of the pH of the electrolite + cycle of charge and discharge with a pulse charger; maintenance-free battery (big problem) we open as we can even treatment and close as we little.

you see it's very simple

@+

PS: Must not take the priests with split plates or without fleet for 10 years

[Woodcutter]

super interesting your article, freddau, bravo.

I still believe that the simplest and cheapest is to make hot water: [...]

Well, it's not stupid, that ... Did you try to simulate a domestic installation to see?
Do you have an isolated reserve of very hot water or are you plugging directly into the heater?