Imprimir

Energy

Ways of Hydrogen

Electrocell makes the final adjustments to the fuel cell that will be handed over to Eletropaulo

MIGUEL BOYAYANElectrocell’s first prototype produced 25 watts of electricity MIGUEL BOYAYAN

A piece of equipment 1.5 meters wide, 2 meters high and 1 meter deep, which produces electricity with hydrogen, is the result of five years of research carried out at the São Paulo company Electrocell. By the end of the year, it should be handed over to AES Eletropaulo, the electricity distribution company that serves 24 municipalities, including the capital, from the São Paulo Metropolitan Region. Installed inside it is the so-called fuel cell, a set of modules of electrodes and conductive membranes capable of producing 30 kilowatts (kW) of electricity, enough to supply two or three floors of a building or 40 small houses. It is going to work with hydrogen compressed in a cylinder, although it is also prepared to extract this fuel from natural gas and ethanol (the alcohol used in vehicles). This is the way that a new phase of energy getting started in São Paulo, which now joins a limited group of cities in the world where there are fuel cells in use, albeit still in an alternative and experimental fashion.

It is equipment that concentrates great technological interest and is considered by specialists in the area to be the novelty in energy with great chances for being disseminated now at the beginning of the century. Canadian, American and German companies have now been making the cells, but still to order, without any consistent production line, for a little more than five years. This commercial production comes in the wake of the American space program, started in the 1950’s, which produced cells for the spaceships of the Gemini and Apollo series and, afterwards, for the space shuttles. The objective in space was to produce, besides electricity, water for the astronauts, which is a by-product of this equipment. With technological advances in materials and electronics in the last 15 years, the cells have become cheaper and formatted for use in more commonplace situations.

Fuel cells work like a battery, transforming chemical energy into electrical energy, breaking up the hydrogen molecules that react with the oxygen in the air. In their stationary form, they perform the functions of a generator, though in a smaller size. The most important difference is that they do this in a silent way and without emitting pollutants. Anyone who has stood beside a diesel generator at work knows very well the noise and smoke that it gives off. Thus, the cells are breaking new ground and serve as a powerful tool where concern for the environment and silence win points.

For Eletropaulo, the cells may mean the start of alternative forms of producing electricity. “When we receive the cell, we are going to take it, probably, to a building, where replacement of a no-break (equipment that prevents the paralysis of a computer network) will be simulated”, explains electronic engineer Mara Ellern, a specialist in business analysis at Eletropaulo. “We are going to see how it works and the possible failures.” Before going for field testing, the cells are also going to undergo a final analysis by Professor José Antônio Jardini, from the Energy Engineering and Electrical Automation Department of the Polytechnic School of the University of São Paulo (USP).

The no-breaks usually supply the computer network for 15 minutes, work with huge batteries, and their cost works out at around US$ 1,000 per kW. For doing the same job, the cells tend to come to a price of around US$ 1,500 for the same kW. “The advantage of the cell is that it operates for a time that is limited only by the fuel storage capacity, and it may have an autonomy of many days in operation if connected to natural gas pipes. This means that there is less maintenance, besides which the physical space requirements and the emission of pollutants are diminished.”

“My dream is, in future, to put the cells into a noble application, like in a hospital, because, besides clean and silent electricity without any interruption, they can supply hot water for sterilization”, says Mara. The water is produced because the protons from the hydrogen (after the electrons have been channeled into the production of electricity), find oxygen on the other side, when they pass through the conducting polymeric membrane, in the inside of the cell.

Plans and expectation
To obtain the equipment, Eletropaulo invested R$ 1.7 million in making the cell, with funds from the Sectorial Fund for Energy (CTEnerg), controlled by the Ministry of Science and Technology (MCT) and run by the Brazilian Electricity Regulatory Agency (Aneel). On the side of Electrocell, the expectation for delivering the first commercial product is great. “We developed the first prototypes under FAPESP’s Small Business Innovation Research (PIPE) Program, in work that started in 2000, and which made the company take off”, says electronic engineer Gilberto Janólio, one of the four partners. “Under the PIPE project, we made prototypes of 25 watts (W), 75 watts, and one of 10 kW.” In these projects, including the Eletropaulo project, which involves a final set of five modules of 10 kW each, the researchers from Electrocell are using 90% of the material developed in Brazil. The only imported product in the Proton Exchange Membrane (PEM), which characterizes the kind of cell. This polymer, called Nafion, regarded as the heart of this kind of cell, was developed in the 1960’s by the American company Dupont for the electrolytic production of chloride (using electrolysis, a chemical reaction using an electric current in an aqueous medium). This membrane is installed in the inside of the cell as if in a sandwich, with catalysts and electrodes, one positive and the other negative, on either side. This set goes by the name of Membrane Electrode Assemblies, or MEA.

To put the cell together, the four partners and another 20 collaborators developed the whole of the engineering that involve this equipment. “They are the engineering procedures for building the stack (a set of MEAs), for control, for energy processing, besides the processes of sealing, cooling and integration”, says Janólio. Another product prepared and manufactured by Electrocell are the graphite bipolar plates. These serve to carry and distribute the hydrogen gas within the cell, besides handling the connection between one MEA and another. Aside from the direct work on the cell, all the electrical system had to be set up for transforming the direct current (DC) electricity that the cell produces into the alternating current (AC) used in our daily life.

For Electrocell, the moment is one of assertion. “We are not risking any more, we are producing equipment that is the fruit of technological development”, explains Janólio. “Now, it is not possible to go wrong”, he says. “Our target is to set up a fuel cell factory for serial production in Brazil. To do so, we now have a layout planned to absorb a team of 58 members of staff”, says chemical engineer Gerhard Ett, another partner. Installed in the Technology Companies Incubator Center (Cietec), which is inside the building of the Institute of Nuclear Energy and Research (Ipen), in the campus of the University of São Paulo, the company enjoyed ample scientific and technological support. “In the area of theory and basic research, we had the collaboration of Professor Ernesto Gonzalez, from the São Carlos Chemistry Institute of the University of São Paulo (USP), and in the technological area, from Professor Marcelo Linardi, of Ipen”, says Janólio.

For working inside Ipen, the people from Electrocell, over the last few years, has been very close to Professor Linardi and his group of eight researchers. Amongst the institution’s contributions to Eletrocell’s projects, there is a formal contract for partnership in the development of the electrodes and catalysts. Linardi is finalizing the production in the laboratory of a new kind of MEA. “We have developed layers of electrodes and catalysts that are applied to the Nafion”, says the researcher from Ipen, which is also receiving finance from FAPESP and the Sectorial Fund for Oil and Gas (CTPetro). “We are now applying for a national patent over this product and we will be able to pass on the technology to Electrocell. For Linardi, adopting their own catalysts and electrodes will be very useful for reducing the price of Electrocell’s cell. Another important factor is that this equipment of the PEM type is a natural candidate for use in automobiles. “It is the most versatile kind of cell, for beingusedboth in vehicles and in the stationary form for generating electricity”, Linardi says. All the vehicle manufacturers are currently testing the PEM cell in experimental vehicles, to replace the combustion engine or to supplement it.

Another advantage of the PEM is that it works at low temperatures, of around 80° Celsius (C), which facilitates its installation in motor vehicles. If low temperatures facilitate automotive use, high temperatures bring new advantages. “In another project, we are developing a solid oxide fuel cell (Sofc, in short)”, says the researcher. This cell operates at high temperatures, between 800° and 1.000° C, and in a stationary station works as a co-generator, supplying steam for a boiler, and producing more electricity.

Whatever the type of cell, its dependence on hydrogen is total. And the simplest way of getting it, which would be to use the electrolysis of water, is a process that uses electricity and is very expensive. In these cases, the use of the cell is limited to hydroelectric power stations. As they have no means of stocking this kind of energy, the power stations may, outside peak times, produce hydrogen with the excess not used in the network.

Energy reform
But what will guarantee the success of fuel cells are the reformers, pieces of equipment capable of extracting hydrogen from natural gas, gasoline or methanol. Along these lines, in July this year, the Hydrogen Laboratory of the Physics Institute of the State University of Campinas (Unicamp) presented a reformer of ethanol, the alcohol produced from sugarcane. “It’s a thermochemical reaction, in which reagents and catalysts are used to transform ethanol into hydrogen”, explains researcher Antônio José Marin Neto. The idea of Professor Ennio Peres da Silva, the coordinator of the laboratory and also the executive secretary of National Reference Center for Hydrogen Energy (Ceneh), likewise housed at Unicamp, is to perfect this prototype and put it into a light truck (see Pesquisa Fapesp n° 82) equipped with a fuel cell that is being put together at Ceneh and should be ready at the beginning of 2004.

A world-wide race

In the 1970’s, it was a dream. The so-called “Hydrogen Age” arose in the midst of the great oil crisis, when the producing countries decided on a large increase in the price of crude oil and left doubts in the air as to the real capacity of their reserves. And so the chemical element most encountered on the planet began to be pointed out as the replacement for fossil fuels. But the crisis passed, and hydrogen was forgotten until the 1990’s, when the degradation of the environment, pollution and the greenhouse effect lead to a quest for clean energies. A disquiet that became real at the World Forum in Kyoto in 1997, when a major part of the countries undertook to lessen the level of pollutants in the atmosphere. Environmental concern, added to the emergence of new materials and the cheapening of fuel cells, also one of the gains of the last decade, has led hydrogen once again to come up in discussions on energy.

Since then, billions of dollars are being spent every year to implement and to popularize the cells that produce electricity in a clean and silent manner. The American government alone should invest US$ 5.5 billion on cells over the next ten years. In June this year, the president of the European Commission, Romano Prodi, announced that the member countries are going to invest – 2 billion over five years on researches with hydrogen. In Prodi’s communiqué, there is also the intention to put this fuel and the cells at the head of the energy economy within 20 or 30 years. In Japan, the government’s intention is that 50,000 vehicles driven by fuel cells should be on the streets by 2010. It is a country where, in 2003 alone, US$ 190 million will be spent on research into hydrogen.

With all this, it is to be expected that Brazil will not remain far behind, even though the financial resources here may not be so generous. The country has already shown the capacity for producing fuel cells with two companies, Electrocell and Unitech (see Pesquisa Fapesp n° 70), which have fuel cell prototypes ready. Several research and teaching institutes in the country are engaged in studying the cells and their components, and several companies from the sphere of energy are financing research and development projects, such as Eletropaulo, Petrobras, Copel (PR) and Cemig (MG). Last year, under the coordination of the Ministry of Science and Technology (MCT) and of the Sectorial Fund for Energy, the Brazilian Fuel Cell Program was established. The intention was to group together researchers in this type of equipment in the country, besides setting a target of 50 megawatts (MW) – by way of comparison, the Itaipu hydroelectric power station produces 12,000 MW – for the production of electricity fromcells in ten years.

But up until now, little has been done. “It’s all at a standstill”, says the coordinator of the National Center of Reference for Hydrogen Energy (Ceneh), Ennio Peres da Silva. “Funds have yet to be allocated for this year and the next, and the groups are not working in an integrated manner and they lack a healthy concentration of efforts.” Just as well that there is still time to make a correction to this route, before the country starts buy, in a systematic way, fuel cells from other countries.

The Project
Development of Fuel Cells Integrated with Software and Hardware for Monitoring, Diagnosing, Controlling and Peripherals (nº 00/13120-4); Modality Small Business Innovation Research Program (PIPE); Coordinator Gerhard Ett – Electrocell; Investment R$ 241,580.00 and US$ 24,000.00

Republish