We face a particularly interesting, anticipating this post with the presentation of the technology and fuel cells, in fact it is called a particular solution based on them called BloomEnergy.
It all started in February 2010 when between the media began to spread the news of a "revolution" on energy technologies capable of representing a viable, efficient and clean for the production of energy.
Abandoning ads sensationalist, and in the spirit of this column, let's now see what it really is, even without going into technical exhibitions too complicated.
BLOOMENERGY - WHAT IS IT?
BloomEnergy is the name of an American company founded in 2002 under the name Ion America and later renamed in 2006 under its current name, which has developed and produced a particular type of Fuel Cell based on technology from the aerospace industry developed by Ing. K.R. Sridhar while working on the project for NASA exploration of Mars.
The need of oxygen required the development of a device which, fed with methane and carbon dioxide, in addition obviously electricity, was able to produce precisely oxygen.
With the change of plans of NASA, Sridhar decided to "reverse the process" to produce electricity from natural gas, without passing through combustion.
Found the funds to create the structures necessary for the development of this technology, began the research phase itself which follows the creation of the BloomEnergy Box, or a stack of fuel cells enclosed in a container of small dimensions, made with the technology developed by the company.
The technology developed by BloomEnergy is based on solid oxide fuel cell (SOFC), and the "secret" which is based on their innovativeness is not very clear, there are hypotheses they consider this is the special coating of the anode and cathode, while other assumptions attribute these characteristics to the materials used for ceramic tiles that are the most obvious part of the fuel cell, but to date it does not seem clear what this peculiarity.
An image of a "slice" with the coating anode and cathode is the following:
To be able to provide substantial amounts of energy were made of the server, overo of large blocks of fuel cells enclosed in units of the size of small containers, which are connected between them can provide the scalibilità in terms of power and energy required by the loads:
Some servers have been installed and tested by several well-known companies in the U.S. and around the world, such as Ebay, Google, FedEx and others, and the results have been encouraging, according to BloomEnergy and companies that have hosted the server, allowing a substantial saving in economic terms compared to the purchase of energy.
BLOOMENERGY - HOW IT WORKS
The solution proposed by BloomEnergy resolutive appears as compared to the main problem which characterizes the production of energy, namely that relating to emissions, because of several parts was considered a clean technology as there is the presence of combustion.
The process requires as "fuel" methane or natural gas, but for simplicity it is better to refer to the methane whose chemical formula is known to most, which combines with oxygen in the air and produces carbon dioxide and water vapor as products :
CH4 + 2O2 → CO2 + 2H2O
From an analysis of such a chemical reaction will not notice any difference with the combustion of methane, except for the presence in the typical case of combustion of components such as nitrogen oxides NOx (in the case of combustion of natural gas or methane production has not of particulates and sulfur oxides), also this reaction produces an amount of CO2 absolutely identical to the amount produced by the same amount of fuel in case of use in a combustion system, and the energy released by the reaction and therefore usable for the purposes of conversion electricity is exactly the same.
From this first point is obvious as it may be considered a solution "green" only as long as you do not refer to CO2, the amount of which referred to the unit of methane consumed is the same.
An important point that can differentiate in environmental terms this solution resides in the efficiency compared to a conventional, or which is the percentage of primary energy (chemical energy of the fuel) which is converted into electrical energy actually measured at the points of connection of the plant with the network or with the user.
As far as a modern combined cycle plant efficiency that stands sul58 - 60%, with a growing trend towards 65% in the future, while the solution proposed by BloomEnergy (as calculated from the nominal power consumption indicated by the manufacturer) has a yield of about 52%.
The cost of this solution is approximately 800 thousand American dollars for the solution 100kW rated power, and the useful life is assessed in 10 years of operation.
These data certainly will be subject to an improvement with the industrialization of production, so it is desirable to reduce the cost of such devices and a longer useful life, mainly because the equivalent thermoelectric have operational lives over 20 years.
The cost per kWh is shown as more convenient than a conventional thermal power plant, although on this point there seem to be because of the validated data to evaluate the cost per kWh must also take into account the cost of the system and the large variability of Speeds in kWh for traditional technologies as a function of the type of plant and the fuel used, therefore the current state seems implausible that convenience.
From this analysis, the doubt remains as to which is the real benefit of this solution, heavily sponsored by celebrities such as former U.S. Secretary of State Colin Powell, and in fact it seems that the hype created around this technology is largely exaggerated , but we must recognize some interesting qualities, including all its compactness and scalability that allows a use for distributed generation, by which it is possible to reduce the energy losses of the distribution lines, but they introduce other hand problems network management that require careful design of the same.
Translated via software
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