The battle of Blue Fuel with Blue Energy - myth or reality?

This time I was forced to sit at the keyboard by a recent article in Vedomosti about the mysterious blue energy that threatens Gazprom’s power in Europe. The bold forecasts of the ladies' group of authors amazed with their prospects. According to their calculations, it turned out that by using the three largest rivers in the EU, the Danube, the Rhine and the Vistula, to produce blue energy, only 10% of the potential can produce electricity 3 times more than all EU countries managed to consume in 2012. It is promised that the cost of energy received after several years of technology improvements should drop to 8 eurocents. For comparison, today the cost of 1 kWh of wind electricity in Europe is 10-20 eurocents, and coal 6-10 eurocents, depending on the generation technology.

The conclusion made by the journalists was very bold. In just a few years of development, new technologies can significantly displace the use of gas as a source for generating electricity and allow the European Union to reduce gas demand by 35-40%. This means that if the “blue energy” is successful, Russian blue fuel will cease to be relevant for Europe.

I turned out to be less optimistic than the girls, and decided to dig deeper to understand whether Gazprom and the shale gas developers should be afraid of a new competitor. I invite those wishing to get acquainted with my micro-research under cat.

A brief excursion into history

As many have probably guessed from the context of entry, we are talking about energy obtained on the basis of the osmotic effect. The phenomenon of osmosis has long been known. It was first observed by A. Podlo in 1748, but a detailed study began a century later. In 1877, the German botanist Wilhelm Pfeffer first measured the osmotic pressure when studying aqueous solutions of cane sugar.


Wilhelm Pfeffer

In 1887, Van Hoff based on the data of Pfeffer's experiments established a law that determines the osmotic pressure depending on the concentration of the solute and temperature. He showed that the osmotic pressure of the solution is numerically equal to the pressure that the molecules of the solute would exert if they were in a gaseous state at the same temperature and concentration.

Technology

So, where rivers flow into the seas and oceans, we have huge sources of both fresh and salt water in the neighborhood - this is an ideal place for the construction of osmotic power plants. How to get energy? The easiest way is to place water in a tank that is divided into two compartments with a semi-permeable membrane.



Sea water is supplied to one compartment, and fresh to another. Due to the different concentration of salts in sea and fresh water, water molecules from the fresh compartment, trying to even out the salt concentration, pass through the membrane into the marine compartment. As a result of this process, excess pressure is generated in the seawater compartment, which in turn is used to rotate the hydroturbine generating electricity.

There are alternative ways. One of them was proposed by the Italian Doriano Brogioli. The basis of its technology is a double electric layer capacitor. “The basic idea is that the potential of the double electric layer depends on the concentration of ions,” says the inventor.

He proposed constructing such a capacitor from two plates made of highly porous carbon. First, seawater is fed into it, in which, as you know, a certain amount of chlorine and sodium ions is always present. To start the system in operation, voltage should be applied to the plates from the “starting” power source. Then a positive electrode will attract chlorine ions, and a negative one will attract sodium ions.

Next, fresh water is supplied to the device. The difference in salt concentration makes the ions leave the plates and go away, overcoming the action of electrostatic forces. The voltage at the electrodes increases noticeably. In the future, the system itself generates current, while the device receives salt and fresh water. A similar solution was proposed by physicist Roberto De Luca, also Italian, only his field created a permanent magnet.

Reality

However, only the first method went beyond laboratory research facilities. On November 24, 2009, Norway launched the first power plant in the world based on the osmotic effect.

It was built by Statkraft in the town of Toft, on the territory of the Södra Cell Tofte pulp and paper mill. The construction of the power plant cost $ 20 million and required ten years of research and development of technology.



1: Exterior view of a power plant in Tofte, south of Oslo. 2: Pre-filtering water to prevent clogging of membranes. 3: The membranes are rolled up in sealed vessels to create high pressure. 4: The turbine used to generate electricity.

Immediately after the launch, this power plant generated no more than four kilowatts of electric energy, however, in the course of improving the technology, the creators planned to increase this value to as much as 10 kilowatts. Have they succeeded so far in secrecy, covered with darkness, as well as whether the plans for the construction of a power plant for a village of 10 thousand private houses will come true this year.

Until recently, the power station in Norway was the only one in the world, but according to Vedomosti, the Netherlands joined the race. On November 26, 2014, a small REDstack BV plant was launched in Afsloitdeyk. According to some sources, the power of their experimental power plant may already be 50 kW. It was funded by the Dutch government.

Sleep well, our property! The battle is postponed.

So, theoretically, due to the osmotic effect, it is possible to obtain a pressure equivalent to a 120 meter column of water and using a flow of one cubic meter per second generate energy with a capacity of 1 MW. Almost today, this parameter is 2-3 watts. The immediate goal of scientists is to achieve a level of 5 watts, which, according to them, can bring technology closer to self-sufficiency.

It seems that while Gazprom can calm down, focusing its activities on the problems arising from the reduction in the cost of shale gas production and seeing how the plant launched in the Netherlands reaches its full capacity, sufficient to satisfy the needs of 800,000 residents, only in nightmares.

There are too many unsolved problems with the “blue water energy”. The main stumbling block in the membranes. It is necessary to increase their effectiveness in a revolutionary way, while reducing cost. Making membranes withstand tremendous pressure will not be easy either. And finally, we must not forget that the water must be very well cleaned before being fed to the power unit, otherwise the membranes will be too short. Creating cheap and effective filters will also be very difficult. Oh, where is Chubais with his Rusnano!

An important addition. Intrigue persists!

Thanks to the meticulous (in the good sense of the word) user, under the nickname AYrm, I managed to find information on what is meant by Blue Energy (BlueTech®). There are not too many details, but it is better than nothing. It turned out that the power plant built by REDstack and Fujifilm near Afsluitdijk in the Netherlands is based on Reverse Electro Dialysis (RED) technology. I specially retain the original names in order to facilitate the task for those who decide to try their luck in the search for details. Fujifilm's main contribution seems to be the development of a key component - membranes.
However, the additional information that was found so far is extremely stingy. It is clear that the bath technology does not use hydroturbines. It seems that it uses the principle proposed by the Italian Doriano Brogioli I mentioned above or very similar to it. The object itself seems to be built.

The project’s home site states that the launch of the pilot unit was scheduled for February 14, 2014, with a capacity of 50 kW. I could not find information about whether this event occurred on time and whether it turned out to be successful. Thus, the intrigue persists. Either the project is classified for the time being from the extra attention of energy monsters exploiting fossil fuels, or something went wrong. Time will tell if Gazprom can relax.
In conclusion, I quote a link to the REDstack company website promoting this technology. There is also an advertising video on which, however, you can watch only the laboratory setup.
http://www.redstack.nl/
The most detailed way to produce osmotic energy without using turbines proposed by Doriano Brojioli in Russian is described here:
http://elementy.ru/news/431152?page_design=print

Well, now my conscience is clear !