Economy & Energy
Ano XII-No 66
February - March
2008
ISSN 1518-2932

 

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Convergence of Agriculture and Energy:

I.Celullosic Biomass Production for Biofuels and Electricity

Hydrogen and Fuel Cells

CO2 Emissões from Fuel Combustion

Comparison between the IEA Values and those of e&e/MCT

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O Crepúsculo do Petróleo
Mauro F. P. Porto

 

Hydrogen and Fuel Cells

Marcelo Linardi
mlinardi@ipen.br (*[1])

Introduction

The concept of the new energy equipment called Fuel Cell is attracting increasing interest in the general public and it is not restricted to the technical, scientific and entrepreneurial communities anymore. This concept has been always associated with the increasing concern regarding environment preservation, non-polluting electric cars and more efficient distributed energy generation. However, the fuel cell concept is more comprehensive and is inserted in the so called “Hydrogen Economy”.

Hydrogen

Hydrogen is the most abundant element in the universe. On Earth hydrogen is almost completely in the form of compounds corresponding approximately to 70% of the planet surface. It was identified by the British scientist Henry Cavendish in 1776 and denominated “inflammable air”/RIFKIN 2003/. Hydrogen gas (H2) is not present in nature in significant quantities and therefore it is an energy vector, that is, it is an energy carrier. For its use for energy purposes or not, it must be extracted from a primary source that contains it. The contained energy of 1.0 kg of hydrogen corresponds to the energy of 2.75 kg of gasoline. However, due to its specific mass (0.0899 kgNm-3 at 0°C and 1 atm), the energy of one liter of hydrogen is equivalent to the energy of 0.27 liters of gasoline/ HOFFMANN 2005/.

Its extraction is quite flexible and this is one of its most interesting characteristics. It can be obtained using electric energy (via water electrolysis) from hydroelectric, geothermal, eolic and photovoltaic sources and also from the electricity of nuclear power plants. It can also be obtained from biomass energy (via catalytic reform or gasification followed by purification) like ethanol, garbage, agriculture waste, etc. However, the more viable hydrogen sources are fossil fuels such as petroleum, coal and natural gas. This flexibility relative to its extraction permits each country to choose the best way of obtaining hydrogen according to its individual possibilities. Therefore, for example Russia has the hydrogen from the nuclear energy option /HTEP 2006/; Argentina, on the other hand, has chosen hydrogen from eolic source /HYFUSEN 2005/ and Brazil will produce hydrogen using bio-ethanol /MCT 2002/.

Presently, the non-energy applications of hydrogen correspond to 50%, petroleum refining, 40% and energy uses, 10%/ WINTER 2000/. Therefore the energy use of hydrogen is not a novelty. Whenever one hears about hydrogen one immediately thinks of a renewable and clean energy source. It is not exactly that. This idea is only true if hydrogen comes from a renewable source and in this case it is called “green hydrogen”. If the source is a fossil, it is called “black hydrogen”, which is produced emitting noxious products to the environment. Therefore, one should be careful to arrive at hasty conclusions about the subject.

The Hydrogen Economy

The history of humanity shows different periods of various uses of primary energy sources. One could mention wood as the first primary energy source used by men /MARCHETTI 1990/. It is followed by the coal era that, associated with technological developments, made possible the industrial revolution in England. This period is called the “Coal Economy” when a large part of the energy that fed the economy was coal. It was then followed by the “Petroleum Economy” which is the present one together with the rise of the “Natural Gas Economy”. It is interesting to notice that there was a progressive de-carbonization of the primary energy sources and methane is presently the cleanest source from the environment point of view /BARBIR 2005/. One is also living a growing “Nuclear Economy” era that however is growing slowly due to public acceptance and non-proliferation factors /MARCHETTI 1990/. Its future is uncertain even though some specialists affirm with some reason that in large scale it is not possible to prevent this form of energy production in the near future. /SCHNEIDER 2007//MACDONALD 2004/.

Another interesting consideration regards geography. All natural resources of primary energy were or are located in certain regions of the planet and naturally benefiting these regions. This inevitable fact has generated political-economical conflicts and even wars.

Considering that fossil sources are finite and therefore their prices of course grow progressively, its consumption is inefficient from the energy point of view, the location of its reserves generate political conflicts and finally, but not less important, its burning generates noxious emissions to the environment (except the nuclear), one could fancy a “Hydrogen Economy”. It is projected that in the 2080 decade 90% of the energy will come from hydrogen. It is projected that in the 2080s 90% of the energy will come fro hydrogen /MARCHETTI 1990/. Natural gas, as the main hydrogen source, will certainly be the bridge between the non-fossil black and green hydrogen in this period. Then around 2080 the polluting emissions to the environment would be insignificant; the chemical/electric energy conversion efficiency would be at least twice the present one and the geo-political conflicts would be attenuated. Is this future panorama just a dream? All the above mentioned factors are corroborated with the introduction of the “Hydrogen Economy” in our society. What are then the critical points regarding this development? The first one is the fact that hydrogen is an energy vector, that is, it is not available in nature and it must be obtained from a primary source that contains it and presently its costs are increasing to values that are not commercially competitive for energy ends in large scale. Other critical points would be its safe handling, storage and transport and not less important, the development and price of fuel cells, the most adequate equipment for its conversion into electric (and thermal) energy. The debate is ample, necessary and sometimes controversial but it’s open to discussion not only in the scientific community but also including the politicians responsible for the strategic actions and entrepreneurs of the sectors. 

However, one can mention some consensus regarding the accomplished future of hydrogen economy. The first one is that it has already started and so it is not a “future matter”, as it is frequently heard. The fuel cells technology from hydrogen production to storage and transport exist even though not mature. The environmental degradation and its consequences like global warming is an unsustainable fact in the medium and long run /IPCC 2000/. Therefore what is missing to accelerate the introduction of this new technology in the planet? In summary, costs reduction both in hydrogen and fuel cell production, development of the same technologies for automotive applications, stationary and portable, and installation of adequate infrastructure for its use. It is useful to make a comparison at this point. Imagine the initial times when cars were invented. There was no infrastructure for cars circulation which had prohibitive prices. Gasoline was neither cheap nor found at every corner. But approximately one hundred years later, cars became accessible, there are roads for its circulation and one can gas up anywhere, that is, we have learned to cope with the fuel, mass production and the market, prices have gone down. This same learning curve is obviously valid for the “Hydrogen Economy”. However, the technological development should start early enough in order to harvest the fruits in the appropriate time.

Another big change will be produced with the introduction of the “Hydrogen Economy”. The fuel cells are suited for distributed electric energy generation with units of relative small size (a few Watts to few MW), when compared to the present power plants (of up to million MW) /BARBIR 2006/. Distributed electric energy generation means in loco generation independent of the network, using hydrogen or more adequately a hydrogen-rich primary source, to be locally reformed. Another parallel is valid here: the big computers at the start of the 1980s (main frame) that represent the present centralized electric energy production system vis-à-vis the personal computer of everyone nowadays that represents the distributed electric energy generation that avoids expensive transmission lines and consequently increases the reliability of this locally produced energy avoiding or minimizing blackouts.

One final observation: since hydrogen can be obtained in different ways, any country or region of the planet can obtain it (see Hydrogen item in the present article). In this case with the introduction of the “Hydrogen Economy” we have for the first time in the history of humankind a democratization of the energy sources that for sure will generate more progress and less political tensions /RIFKIN 2003/.

The Fuel Cell

In principle fuel cells are batteries, that is, they directly convert chemical energy into electric or thermal one, that operate continuously (as opposed to conventional batteries) that produce continuous current through cold electrochemical combustion of a fuel, generally hydrogen /VIELSTICH 2003/. Therefore, considering cells that operate at low temperature in acid environment, hydrogen is oxidized to protons in the anode and liberating electrons, according to the reaction:

H2   ®   2H+   +   2e-                                                                                              (1)

In the opposite electrode, the cathode, one has the reaction:

2H+  +  2e-  +  ½O2  ®  H2O                                                                               (2)

The global reaction produces water and heat (exothermic):

H2   +   ½O2   ®   H2O                                                                                         (3)

The electrodes are electronic conductors permeable to the reacting gases and are separated from each other by an electrolyte (ionic conductor). The electrolyte can be a liquid, cation-conductor polymer (generally saturated by a liquid) or a solid.

Unit cells present an open potential from 1 to 1.2 V and under load liberate from 0.5 to 0.7 V DC. These values are very low from the practical point of view. The need of stacking several cell units in series (from 200 to 300, also called module) is obvious so that one can have potentials from 150 to 200 V  /WENDT 2000/. One of the advantages inherent to fuel cells is its efficiency relative to the fuel. The maximum theoretical efficiency h of any process is the ratio between the Gibbs (DG) free energy and the total enthalpy (DH), that is, the part of the total energy of the reagents that can be converted into electric energy:

 h   =   DG/DH                                                                                                          (4)

 The theoretical electrochemical efficiency decreases from 86 to 70% in the 100 to 1000 °C temperature range. On the other hand, the Carnot efficiency increases from 0 to 70% in the same range and only at temperatures above 1000 °C it is larger than the theoretical electrochemical efficiency /APPLEBY 1989/. Therefore, hydrogen fuel cells present a theoretical efficiency significantly higher than Carnot machines, mainly at low temperatures.

Electrodic reactions in fuel cells involve in a general way the rupture of chemical bonds between two hydrogen and oxygen atoms. The breaking of the diatomic H2 and O2 molecules requires an activation energy of the same order of magnitude of its formation energies when the reactions are homogeneous and occur in the gaseous phase /TICIANELLI 2005/. However, in fuel cells both reactions are heterogeneous and occur at the electrode/electrolyte interface and are catalyzed at the electrode surface.

Generally the different types of fuel cells are classified by the type of electrolyte used and consequently by the operation temperature /VIELSTICH 2003/. The main types of low-temperature operation cells (from room temperature to 200°C) are /LINARDI 2002/:

(a) Alkaline Fuel Cell or simply AFC. This type of cell has presently an important role only regarding restricted applications such as spaceships or situations where ultra pure hydrogen is available. This type of cell is the precursor of the more modern cells;

 (b) Proton Exchange Membrane Fuel Cell, or PEMFC that operates from room temperature up to 80°C. They are the most promising ones as alternative to electro-traction, to substitute internal combustion engines. These cells present the advantages of being robust and being easily turned on and of, and having high efficiency and low (or zero) polluting emissions. They can also be used in stationary units for local energy generation like cell telephones and laptops. The determining factor for its commercialization is still its cost. As electrolitic polymer it is used the Nafion® membrane, composed of perfluorinated polymer from tetrafluoroethylene, where in one of its side one ether connects with perfluorinated ethyl-sulfonic (ionogenic group) acid. The ends of the chain, where the sulfonic acid is located, form a kind of bubble in the structure that swells in contact with water or water vapor. These bubbles, that are interconnected, are responsible for conducting protons and water through the membrane under the effect of an electric field /VIELSTICH 2003/. The commercial use of this type of cell was initially unimaginable due to the large quantity of platinum as an electric catalyst necessary for the electrode fabrication. The change occurred with the use of carbon black as platinum holder. Besides that, following the idea introduced by Raistrick and Gottesfeld /RAISTRICK 1986//GOTTESFELD 1992/, it was realized at the star of the 1990s that the platinum surface could be used more efficiently when the inner surface of the holder contacted the ionomer of the membrane. This process produces platinum nanocrystals dispersed in the holder that is in contact with the electrolite (Nafion®, DuPont). This fact has reduced the necessary platinum quantity and made viable the commercialization of this type of cell. The most studied R&D areas regarding PEMFC cells involve on one side the development of more active and specific electro-catalyst both for direct alcohols oxidizing (methanol and ethanol) with hydrogen-contaminated CO and on the other side the development of new electrolytes that permit the operation of these cells above 100°C, increasing their efficiency and longevity.

(c) Phosphoric Acid Fuel Cell or PAFC. Developed at the end of the 1960s, this type of cell represented a significant technological progress in the area. This cell is not sensitive to carbon dioxide and is little sensitive to carbon monoxide that poisons the catalyst in PEMFC cells permitting a content up to 1% of CO in the feeding gas at 200°C, its operation temperature. The development of this cell had from the start the objective of winning the important market of methane-burning plants/WENDT 2000/, reactions (5) and (6):

                CH4   +   H2O   ®   CO   +   3H2                                                                      (5)

                CO   +   H2O   ®   CO2   +   H2                                                                        (6)

In the PAFC cells silicon carbide with an average diameter of 0.1 mm is used as a holder material (matrix) to support the electrolyte (phosphoric acid). Even though this is presently the most commercialized type of cell in the world, the PAFC cells did not have either much progress in the last years or significant costs reduction relative to the present one, namely US$ 4.000 for installed kW.

In the low-temperature operating cells the reactions occur in the so called gaseous diffusion electrodes that are an electron-conducting porous structure of the electrode/electron-catalyst system with platinum base. The construction of these electrodes has the function of maximizing the gas-liquid-solid three-phase interface and therefore considerably increasing the electrodic processes velocity. The present R&D development in these type of cells involve new selective electron-catalysts, materials, components and more economic processes besides the optimization of the system engineering.

For fuel cells at high operation temperature there is no need of using noble metals as catalysts because in this temperature range the electrode metal itself is sufficiently active. The main types of high operation temperature cells are /LINARDI 2002/:

(a) Molten Carbonate Fuel Cell or MCFC. For molten carbonate cells that operate at 600°C nickel is used as the electrode material and nickel oxide with lithium incrustations in the cathode that is a p-type semiconductor. In the molten carbonate cells it is used a LiAlO2 particle matrix to accommodate the electrolyte, a mixture of molten carbonates. In this type of cell the natural gas endothermal reform for hydrogen generation can be carried out in the unit cell column itself and thus eliminating the reformer and at the same time cooling the cells, optimizing the system engineering and reducing costs;

 (b) Solid Oxide Fuel Cell or SOFC operate in the 800°C - 1000°C range .In the case of ceramic cells a Ni/ZrO2 cermet is used as anode material, that is, a zirconium oxide matrix stabilized with finely distributed nickel. In the cathode it is used a manganese and lanthanum compound doped with strontium, La(Sr)MnO3 and LaCrO3 is the material used as the stacking interconnection (power module). This type of cell presents some advantages relative to other types such as simple electrolyte management (because it is solid) and the unnecessary use of noble metals as catalysts. Furthermore, they have higher theoretical conversion values and have a high electricity/heat co-generation capacity. The high operation temperature favors the electrodic reactions kinetics and permits the reform of the primary fuel for hydrogen production in the cell structure itself. The main application of this type of cell is energy generation in stationary units. However, the high operation temperature brings technological limitations such favoring the degradation and fatigue of the different components, thermal stress, among others. Recent R&D developments try to find materials that permit its operation at temperatures below 800°Cand costs reduction.

These two types of cells, MCFC and SOFC, are presently in a technological development phase and technical-economical demonstration /FCSEMINAR 2007/.

The International Partnership for the Hydrogen Economy (IPHE)

Under the direction of the Ministry of Mines and Energy (MME) and with the collaboration of many specialist in the field, it was elaborated a preliminary document that will guide the Brazilian government actions to introduce the country in the “Hydrogen Economy” and it is called “Road for Structuring the Hydrogen Economy in Brazil”, available at /HTTP 1/.

The most relevant topics of this document are:

(a) In 2020 hydrogen will be part of the energy matrix of the country;

(b) Ethanol was chosen as the main hydrogen source. It is also considered its direct use (direct oxidizing in fuel cells);

(c) Hydrogen production via water electrolysis is considered, using the secondary electricity from hydroelectric power plants;

(d) Other biomass sources besides sugarcane should be used for hydrogen production, including biogas;

(e) The use of natural gas as hydrogen source will be the transition for the future with only green hydrogen;

(f) The applications of this energy source are in order of importance: distributed energy generation, energy production in isolated regions and urban buses.

At the world level it was created by the United States an international cooperation program called “International Partnership for the Hydrogen Economy”, (IPHE), with the participation of 17 countries with the main objective of implementing, promoting and establishing R$D$I activities and market development regarding hydrogen and fuel cells technologies.

The member countries are: Australia, Brazil, Canada, China, European Community, France, Germany, Iceland, India, Italy, Japan, South Korea, New Zeeland, Norway, Russia, United Kingdom and the United States. Brazil is the only Latin American member. These countries represent 85% of the world GDP with 3.5 billion people and more than 75% of the world electricity consumption besides more than 2/3 of CO2 emissions /HTTP 2/. Examining the member of this forum and the relevant data mentioned above one can notice the importance of the matter that demands a change in the model regarding the world energy matrix in the next decades.

The IPHE responsibilities can be summarized as follows: implement technical cooperation fields, support and select projects involving hydrogen and fuel cells, create task forces for developing strategies for development and dissemination of the hydrogen economy, create and expand roadmaps such as the “IPHE Priority Scorecard and Activities Matrix”.

This forum is composed of two committees that meet annually: the Steering Committee (SC) and the Implementation and Liaison Committee (ILC).

Due to this change of model that presupposes radical changes in well established sectors of the economy and society, the IPHE has decided to hold the 7th meeting of the Steering Committee in Brazil, São Paulo, from 23 to 26 April, 2007 in order to learn from the Brazilian experience regarding automotive fuels that introduced drastic changes from 1975 up to now concerning the introduction of renewable fuel, namely ethanol, in large scale.

The introduction of biodiesel was considered in this apprenticeship. That is, the international community wanted to know how Brazil had overcome the obstacles regarding the change in its transport energy matrix /HERALD 2005/. This apprenticeship can be useful for the transition to the “Hydrogen Economy”. The main highlights of this apprenticeship were presented by specialists from MME and MCT and some Brazilian scientists. The actions contemplated in 1975 by PROALCOOL are listed below:

(a) Maintenance of alcohol initial price below that of gasoline;

(b) Guarantee of the alcohol producer remuneration;

(c) Reduction of taxes and duties regarding alcohol-fueled cars;

(d) Incentives to alcohol producers in order to increase production capacity;

(e) Compulsory supply of alcohol in all fuel stations in the national territory;

(f) Maintenance of alcohol regulatory stocks.

It was pointed out to the Steering Committee members that the above measures were important in the initial phase and only after the technology development of the Flex type cars and the return of the fuel free market it was possible to have a successful program. Only the item c) was maintained until now, that is, tax reduction concerning the Flex cars. All other measures were eliminated.

A parallel with the “Hydrogen Economy” can be drawn, for example, incentives to initial hydrogen production, guarantee of competitive prices and compulsory supply to practical applications. The intensive development of fuel cell technologies always aiming at cost reduction for different applications is associated with these actions. The goals regarding costs are approximately US$ 2,000 per installed kW for stationary applications of electric energy and US$ 200 per installed kW for mobile applications. It was pointed out only the economic character of the technology but not the environmental ones which can become in the near future as important in our society just as the financial one.

The Brazilian Fuel Cell and Hydrogen Program

The Brazilian Hydrogen and Fuel Cell Systems Program (initially denominated PROCAC) was drawn up in 2002 by MCT with the participation of universities, research centers and Brazilian enterprises aiming at promoting integrated and cooperative actions for developing the national hydrogen and fuel cells systems technology so that the country could become an internationally competitive producer in this area. This program also intends to support the establishment of a national industry for the production and supply of fuel cells energy systems. Among the different identified challenges, besides the development of fuel cells, one can mention the production, storage and distribution of hydrogen, human resources training, and regulation regarding safety and standardization and the need of partnership involving governmental institutions, the industrial sector, the service sector, NGO, etc. In 2005 PROCAC was given a new name- Science, Technology and Innovation for the Hydrogen Economy - PROH2.

The program envisages the creation of research and development networks all over the country. For this purpose, it guarantees the rational use of invested resources and anticipates the achievement of the objectives.

The main PROH2 premises are:

(a) Develop integrated and cooperating actions that will permit the creation of national energy systems technology based on fuel cells aiming at the production of electric energy in a cleaner and more efficient way. It includes the following area: electrochemical, catalysts, fuel cell materials, PEM type fuel cells, SOFC type fuel cells, ethanol reform, natural gas reform, systems connected to fuel cells, etc;

 (b) Create conditions for the establishment of a national industry for the production of energy systems based on fuel cells that includes fuel cell producers, system integrators and service suppliers so that the country will become internationally competitive in this area;

 (c) Incentive to the installation of energy systems based on fuel cells;

 (d) Establish conditions so that the participating institutions will actively collaborate among them in the different involved aspects of research, development and application areas of this technology;

 (e) Promote with efficiency the technology transfer from universities and research centers to the enterprises aiming at increasing the Brazilian economy competitiveness inclusive through international cooperation mechanisms;

 (f) Install and improve the research infrastructure, prepare and train human resources in the area;

 (g) Establish technical norms and standards for certification of processes, technology and products in the area for the different stationary, mobile and portable applications;

 (h) Finance and use the purchase power of the different governmental agents in order to make viable demonstration projects related to the new technology so that they become visible, attract new investments, enable personnel training, carry out technical and economical studies, etc.

The program uses resources from Sectoral Funds (CTPetro; CTEnerg and Verde-Amarelo) and has R$ 7 million available for research from December 2006 onwards and it is managed by FINEP. The program also contemplates some isolated actions of interest according to the Task modality such as, for example, the “Hydrogen Generation from Ethanol Reform”, coordinated by the National Technology Institute” (INT) and has as co-executers the Energy and Nuclear Research Institute (IPEN) and Eletrobrás’ Electric Energy Research Center (CEPEL) that will have R$ 5.8 million available that, besides the development of the reform process, envisages the construction of a PEM type cell module with 5kW nominal electric power using national technology.

Associated with the scientific and technological program one could mention a project for supporting the network laboratories infrastructure managed by the Technology Institute for Development, LACTEC, already finalized, and MSc, PhD and DTI scholarships managed by CNPq, specifically for the human resources formation program.

In the electric-traction application two programs in the country can be highlighted, even though not included in the PROH2 Brazilian program:

 (a) The first one is called “ Energy Environmental Strategy: Bus with Hydrogen Fuel Cell  for Brazil” and envisages the fabrication of 8 test buses using fuel cells (PEM Type from the Ballard enterprise) with hydrogen from electrolysis. Petrobrás will construct hydrogen fuel stations. This project is conducted by the United Nation Global Environment Facility/PNUD (US$ 12.5 million), MME (R$ 4 million) and managed by the São Paulo Metropolitan Urban Transport Enterprise EMTU.

 (b) Project of an urban bus prototype using hydrogen from natural gas reform, coordinated by the COPPE/LACTEC/Petrobras/ELEBRA consortium.

Bio-Hydrogen in Brazil

The Brazilian option, namely hydrogen from ethanol, is due to several factors that makes this choice an interesting one. Ethanol is a liquid fuel that is easy to store and transport and there is in Brazil all the infrastructure for its production, storage and distribution in the whole country. Furthermore, ethanol has other very important characteristics such as presenting low toxicity and it is a biofuel and therefore, renewable. It is a hydrogen-rich input. Ethanol’s share in the national energy matrix has been growing in the last years (in 2006 it corresponded to 14% /MME 2006/), mainly due to two factors: its mixture to gasoline (from 20 to 25%) and the large development and commercial success of the so-called FLEX cars.

Brazilian ethanol produced from sugarcane is presently the most productive biofuel in the world with 6,000 liters/hectare/year, at a cost of US$ 0.22 per liter (anhydrous).This productivity can grow up to 14,000 liters/hectare.year with the development of new technologies. Just for comparison corn ethanol in the USA has a productivity of 3,000 liters/hectare.year. Another interesting point is its excellent energy balance. Each non-renewable Joule used in ethanol production produces 9 renewable Joules. Again for comparison, this ratio for the USA alcohol is 1,5 and the German biodiesel is 3.0 /IEA 2005/.

The present Brazilian production is approximately twenty billion liters per year that corresponds to an occupied plantation area of 3 million hectares (0.35 % of the national territory). The appropriate area for this culture is 12% of the national territory. The Brazilian vegetal cover is 851 million hectares of which 464 million hectares (9%) are fields and savannahs and 17 million hectares (2%) are cities, rivers and others. Mainly the degraded pasture areas could be used for increasing this plantation without impairing therefore our natural resources or food production/MME 2006/.

For the indirect use of ethanol aiming at hydrogen production there are three possible processes: partial oxidizing reform, steam reform and auto-thermal reform. Each process has its own characteristics, advantages and disadvantages. However, auto-thermal reform that consists of a combination of the other two processes has an optimal thermal balance with a reaction temperature of approximately 700°C, reaction (7). The advantages of this process are: high hydrogen yield and the best thermal balance. The main disadvantage is hydrogen dilution with nitrogen that can be circumvented by wrapping up the reactor with a palladium membrane that purifies the final gas.

CH3CH2OH(v) + 2H2O(v) + ½O2(g) ® 2 CO2 (g) + 5H2(g) + 50,0 kJ                    (7)

Other reasons could be pointed out for using ethanol as hydrogen renewable storage, besides its large production and distribution all over the country: the previous experience regarding norms and commercialization, the fact that it is less toxic than methanol, environmental questions (emission effects from ethanol burning are not well studied yet) /MACEDO 2004/ and efficiency regarding its direct combustion and finally the fact that its distribution is viable in isolated regions of the country.

The Energy and Nuclear Research Institute (IPEN) Program

IPEN has a past of important achievements in the nuclear area. Experience regarding R&D, innovation and coordination of multidisciplinary domains permitted achievements such as nuclear fuel cycle mastering, engineering, construction and operation of research nuclear reactors, radio-pharmaceuticals production, etc. In the educational area, the association with the São Paulo University permitted the implementation of a post-graduation program in the nuclear area that is highly reputed in the country.

Following the world trend, IPEN started in 2000 a new study area concerning more efficient energy sources that have low environmental impact and therefore it has chosen the study and development of systems associated with fuel cell technology. The initial studies were carried out in the materials area using the previous experience of the nuclear area development.

The main objectives of this institutional program include generation of scientific-technological knowledge, innovation and human resources training in the fuel cell area. The program includes institutional actions, safeguarding the intellectual property concerning technological development and innovation. The focus of the program is on distributed electric energy generation. The program has also the responsibility of participating in the group that defines the Brazilian policy for hydrogen (MME) and has intense participation in the organization and operation of PROH2 (MCT).

The organization chart of the program is divided in four groups for scientific-technological development, namely PEMFC, SOFC, HYDROGEN PRODUCTION and SYSTEM. Furthermore, IPEN has a post-graduation course in the area with eight disciplines.

Conclusions

The hydrogen and fuel cells technologies have greatly developed in the last years and they have different applications such as energy generation for electric traction, stationary units and portable ends. The large differential is the low (or zero) environmental impact and high efficiency. Fuel cells are the most appropriate apparatus for using hydrogen as energy vector.

The obstacles to the introduction of the so called “Hydrogen Economy” are not insurmountable. On the contrary, they indicate a list of opportunities for the creation of new enterprises of goods and services in the country, corroborated by the emerging technologies in the sector.

The fuel cell technology has been growing in the last 40 years due to different factors such as the development of the materials area and the growing demand of clean and efficient energy sources. As already established and commercial technologies one could mention the phosphoric acid cell system (PAFC) of the UTC enterprise. But one can talk about economic success only when other competitors will offer similar systems in the market. The perspectives of high-temperature operation cells are certainly promising but there is no offer in large scale of this type of system. The PEMFC type cell technology has not only vehicle applications but also small and medium size stationary units (residences, hospitals, etc.) besides portable uses (laptops and cell phones).

Even tough the fuel cell technology is not completely established its implementation in the market will not take long because it is guaranteed in some niches where the environmental factor is preponderant. Furthermore, depending on its technological development, this energy source in the medium term will have an important role in the world energy panorama.

Fuel cells research in Brazil has been developing since the end of the 1970s in different institutions /TICIANELLI 1989/. The Brazilian government has started late its important and concrete actions in areas relative to other countries (2002) but it is already part of IPHE that manages to establish the “Hydrogen Economy” in our society.

Brazil is elaborating its roadmap for the “Hydrogen Economy” and has a research and development program for fuel cell and hydrogen. Presently various Brazilian institutions are involved in this sector with several projects in progress. New enterprises have presented products for this new technology (Electrocell, Unitech and Novocell, among others). IPEN has played an important role in the national panorama for the development of this technology.

The city of São Paulo does not have to wait a long time in order to have buses moved by fuel cells circulating in the streets. An ambitious environmental project was signed between the United Nations and the Brazilian government through the Ministry of Mines and Energy. This project aims at the use of different buses using hydrogen with PEMFC electric traction in collective transport in the city of São Paulo.

All these considerations permit to say that the “Hydrogen Economy” has already began also in Brazil and it is not merely a matter for the future.

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[1] Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN-SP

 

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