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Hybrids on the streets

Buses with electric and conventional traction, produced in São Bernardo, win international prominence

By running along the streets and avenues of São Bernardo do Campo, in the industrial regional of the ABC in Metro São Paulo, the bus produced by a company called Eletra marks another point for this traditional center of the Brazilian automobile industry. Equipped in an innovative way that combines two forms of propulsion in one and the same vehicle, electricity and a diesel engine, it is a bus that has led the company to be one of the seven finalist institutions in the energy category for the World Technology 2003 award, out of a total of 15 nominated by 700 researchers and organizations from 50 countries that make up the World Technology Network. The award, regarded as a sort of Oscar for technology, is sponsored by companies and organizations of the stature of Nasdaq, Microsoft, DuPont and Time magazine.

This kind of technology is present on a commercial scale in automobiles from the Japanese companies Toyota, with its Prius car, and from Honda, with the Insight. Among buses, there are few manufacturers in the world offering these characteristics – besides Brazil, only the United States has this kind of bus in commercial operation. Amongst the advantages over the conventional ones, there are their low price and environmental gains. According to measurements by the Graduate School and Research in Engineering of the Federal University of Rio de Janeiro (Coppe-UFRJ), the reduction in particulates, or black exhaust fumes, can be as much as 90%, compared with conventional buses. In the overall balance, the emission of pollutants is 63% lower. “With these levels of emission of particulates, our bus already meets the Euro V standard, which will only come into force in Europe in 2008”, says electronic engineer Antônio Vicente de Souza e Silva, the company’s technical director and responsible for the development of the hybrid bus. “In Brazil, Euro II is still in force”, he compares.

The functioning of this bus is based on a system with an internal combustion engine, an electric motor, a generator, and a set of batteries managed by an electronic system that calculates the energy requirements of the vehicle at every moment. “Unlike conventional vehicles, the combustion engine is used only to activate the generator that supplies the vehicles with electricity. The electric motor is responsible for moving the bus and gets the electricity from the generator and from the bank of batteries”, the engineers says. When compared with a trolley bus, the hybrid has the advantage of not depending on the network of overhead wires to get electricity. “The network calls for constant maintenance, is open to mishaps like falling trees and lightning, and it restricts the vehicle’s movement.”

Even when it is at a standstill, the hybrid bus is supplied with the electricity coming from the generator that recharges the batteries. On the flat stretches, when the demand on the electric motor is small, the excess energy is also stored. Making good use of energy also occurs when the brakes are applied. “In a conventional vehicle, the energy of movement is transformed into heat in the braking system and ends up getting lost. In the hybrid bus, the command for braking is recognized by the electronics, which transform the electric motor into a generator, accumulating energy in the batteries, instead of dissipating it in the braking system.”

The fact that the combustion engine is used only to activate the generator makes it possible for its power to be far less than is used in conventional vehicles of the same size. To move a standard bus 12 meters (m) with a conventional traction system, for example, an engine of at least 210 horsepower (hp) is needed, while the hybrid only calls for 80 hp – the power for a van. This reduces the consumption of fuel and lubricating oil, besides reducing expenditure on maintenance of the engine.The company’s sales argument, though, is centered on the reduction of pollutants, of expenditure on fuel and maintenance, and on the durability of the vehicle, which, according to Silva, is at least twice as long. “The useful life of the traditional bus is from five to seven years, while the hybrid ones last the same as trolley buses, that is, 15 years.” With fuel, also according to Coppe, savings vary from 15% to 30%, depending on the route. The reduction in operating costs also extends to the lubricating oil, brake linings, tires and maintenance of the engine.

Multi-make vehicle
The technology of the hybrid buses is adaptable to practically all the makes of bodywork and chassis, which can be chosen in accordance with the needs of the customer. Up until now, bodywork from Marcopolo and Buscar has been used, and chassis from Volvo, Mercedes and Volkswagen. The same happens with the engines. The hybrids produced by Eletra have combustion engines from International or Mercedes and electric motors from Weg and Equacional. “This is important, because the customer sometimes has a fleet with chassis and bodywork of a given make and wants to carry on with it, to facilitate maintenance”, the engineer says.

A standard hybrid 12-meter bus, for example, costs 30% more than a conventional one. The difference falls to 10% in the 18 m articulated model, and goes up to 40% in a minibus. The reason for the variation is that the electronic system has a fixed cost, without any direct relation to the size of the vehicle. Silva guarantees, though, that the 30% difference in the standard bus is paid for in roughly three years, with the savings in consumption and maintenance. A standard 12-m vehicle can be sold on the international market for US$ 150,000. In the United States, a similar model costs around US$ 370,000. According to him, the difference in price occurs for the fact that Brazil is one of the largest producers of bodywork and chassis in the world and has low labor costs.

Eletra still has a timid production. According to the director-president, Maria Beatriz Setti Braga, the company has 14 buses in commercial circulation and is working on the production of 51 vehicles that will be delivered by the end of the semester. “When we begin to produce in larger quantities, our price will come close to the price of a conventional bus”, she promises. She makes it clear, though, that the company does not intend to go into the mass production market, because there is no intention of competing with the major vehicle manufacturers. “Our work will always be to order, as happens with Embraer’s aircraft”, is the example she uses.

Beatriz and her brother João Antônio are the owners of ABC Urban Transports, which has been operating 90 years in São Bernardo. They created Eletra four years ago, to meet a demand from the bus company. “We wanted a vehicle that did not pollute, that wasn’t noisy, and that didn’t consume much fuel. To start with, we thought of buying electric battery buses, but we decided to take advantage of the experience of engineer Antônio e Silva, who worked for many years on the design and production of trolley buses, and to make our own hybrid bus”, says Maria Beatriz.

Paulistão and export
The development of the first bus lasted 12 months and cost about US$ 500,000. According to the president, Eletra’s first buses came into circulation in 1999, a little before the American hybrids, which only started to run in 2000. Four years later, with patents applied for in Brazil, in the United States, in Chile, in Panama and in the countries of the European Union, the company is beginning to close its first big contracts. The first is for the City Hall of São Paulo’s “Paulistão” project, which will be carried out exclusively with hybrid buses. According to the director-president, the contract for producing the first 15 buses has now been signed. Since the end of 2002, Metra – Metropolitan Transport System has been testing three of Eletra’s hybrid buses, on a route of 33 kilometers between the districts of São Mateus and Jabaquara, in São Paulo, which passes through the cities of São Bernardo and Santo André. Exports are also beginning to materialize. The company has one vehicle on demonstration in Chile, where it is going to take part in a large tender to replace the urban fleet of the city of Santiago.

The prestige achieved with the award may speed up the process of the company’s growth. After all, the Brazilian hybrid was chosen from amongst the best projects of technological development in the area of energy by an international jury, competing with companies and universities from various parts of the world. The winner in this category was the Lawrence Berkeley Laboratory, of the University of California, in the United States, for its set of works in the field of energy that resulted in greater efficiency and a reduction in environmental impacts. Amongst the finalist companies, Eletra had Brazilian company in other categories. In the area of social entrepreneurism, the first place was conquered by the teacher of information technology and businessman Rodrigo Baggio, who created the Center for the Democratization of Information Technology, an entity focused on digital inclusion. Also as a finalist in this area, there was the director of the Viva Rio project, Rubem César Fernandes, who offers courses in information technology in poor communities of Rio de Janeiro.