Luiz Augusto Horta Nogueira

Uso racional: a fonte energética oculta

Modern energy systems are complex exploitation networks of natural resources with successive conversion and energy transportation processes and a high level of losses. These losses constitute a virtual energy source that must be better exploited in order to provide economic and environmental advantages. Here, the concept of energy system loss and the evolution of Brazilian institutional framework to enhance the promotion of a rational use of energy will be presented, as well as the perspectives to reduce energy waste in end uses: domestic refrigeration, residential water heat, light vehicles and cogeneration. The estimated total capacities of electric energy and fuel economy (by consuming sectors) are also presented.

Feedstocks for biodiesel production: Brazilian and global perspectives

ABSTRACT Soybean, rapeseed, and palm oil are the main raw materials for biodiesel production worldwide. However, there are other potential feedstocks for biodiesel production. Speculations swirl around the agreements signed at the 21st Conference of the Parties to reduce carbon emissions from the transportation sector and stimulate the biofuel blending. As an increase in the biodiesel demand is expected, Brazil can be an important player in the international market because of the availability of land and the diversity of raw materials. This paper discusses current global oil and biodiesel scenarios and reviews several potential feedstocks focusing on the prospects, limitations, food–fuel nexus, and opportunities to develop added-value products. Despite the variety of potential feedstocks, the biodiesel sector is likely to pursue its development based on large-scale economically competitive alternatives. Animal fat and waste frying oil are options for a short-term scenario. Palm oil is a promising choice for medium term, while algae and second generation routes may contribute to the biodiesel supply in the long term. Development of competitive chains, investment in technologies, processes and logistics, and domestication of species are essential to guarantee the inclusion of such feedstocks in the world biofuel mix.

Perspectives for Sustainable Aviation Biofuels in Brazil

The aviation industry has set ambitious goals to reduce carbon emissions in coming decades. The strategy involves the use of sustainable biofuels, aiming to achieve benefits from environmental, social, and economic perspectives. In this context, Brazilian conditions are favorable, with a mature agroindustry that regularly produces automotive biofuel largely adopted by Brazilian road vehicles, while air transportation has been growing at an accelerating pace and a modern aircraft industry is in place. This paper presents the main conclusions and recommendations from a broad assessment of the technological, economic, and sustainability challenges and opportunities associated with the development of drop-in aviation biofuels in Brazil. It was written by a research team that prepared the initial reports and conducted eight workshops with the active participation of more than 30 stakeholders encompassing the private sector, government institutions, NGOs, and academia. The main outcome was a set of guidelines for establishing a new biofuels industry, including recommendations for (a) filling the identified research and development knowledge gaps in the production of sustainable feedstock; (b) overcoming the barriers in conversion technology, including scaling-up issues; (c) promoting greater involvement and interaction between private and government stakeholders; and (d) creating a national strategy to promote the development of aviation biofuels.

Ethanol from Sugarcane in Brazil: Economic Perspectives

Abstract Since 1931 the gasoline sold in all Brazilian gas stations has been mandatorily blended with ethanol from sugarcane, adopting in average 7.5% of this biofuel. As a reaction to the oil shock in the 1970s, from 1975 the production and use of ethanol in Brazil registered a strongexpansion due to government incentives to increase ethanol blending to 25% and introducevehicles able to use pure hydrous ethanol. In this period, a considerable reduction in production costs and productivity gainswereobserved. In the 2000s, with the advent of flex-fuel cars and the growing concern about sustainability of energy systems, the ethanol industry returned to growth. However, inrecent years government hasintroduced gasoline subsidies, reducing ethanol consumption and inhibiting investments in greenfield ethanol production units. In this paper, the development of ethanol production and use in Brazil are commented, presenting the evolution of ethanol costs and prices.

Incentives and Barriers for Liquid Biofuels in Brazil

Bioenergy has been an important share of the Brazilian energy matrix, supported by an ample basis of natural resources, an appropriate climate, large availability of land and water, and enough expertise on agriculture and forestry management. Currently, ethanol and biodiesel supply about 20% of road transport fuel in Brazil, with the major contribution of ethanol. Since the early 1900s, ethanol-blended gasoline has been used in Brazil, but a national program aimed at market development was only launched in the 1970s. Further, the production and use of biodiesel started just in 2005 with progressive blends with diesel. Gasoline has more than 20% anhydrous ethanol by volume, and hydrated ethanol is traded freely. In turn, biodiesel is blended with diesel at 7% by volume, with plans to increase to 10%. Both Brazilian biofuel programs demonstrate the relevance of adopting efficient agroindustrial strategies as well as the possibility of sound coexistence between bioenergy and other uses of agriculture. This chapter presents a summary of the evolution of ethanol and biodiesel programs in Brazil, focusing on the institutional aspects and the decisive role of public policies to foster the development of the biofuel market.

Biomass Gasification for Ethanol Production

For a sustainable future, it is essential for mankind to access the largely untapped solar resource by innovative bioenergy routes, an important way to overcome fossil fuel dependence and mitigate related environmental impacts. In this framework, as a good example of the potential to be exploited, among the several biomasses under scrutiny to be used for energy supply, sugarcane appears as one with the most interest and potential, with estimates that about 142 million hectares currently are available for such culture, taking into consideration rain feed areas in tropical countries and without significant impact on food production and the environment (Fischer et al.2008).

REPOWERING: AN OPTION FOR REFURBISHMENT OF OLD THERMAL POWER PLANTS IN LATIN-AMERICAN COUNTRIES

The operational rules for the electricity markets in Latin America are changing at the same time that the electricity power plants are being subjected to stronger environmental restrictions, fierce competition and free market rules. This is forcing the conventional power plants owners to evaluate the operation of their power plants. Those thermal power plants were built between the 1960´s and the 1990´s. They are old and inefficient, therefore generating expensive electricity and polluting the environment. This study presents the repowering of thermal power plants based on the analysis of three basic concepts: the thermal configuration of the different technological solutions, the costs of the generated electricity and the environmental impact produced by the decrease of the pollutants generated during the electricity production. The case study for the present paper is an Ecuadorian 73 MWe power output steam power plant erected at the end of the 1970´s and has been operating continuously for over 30 years. Six repowering options are studied, focusing the increase of the installed capacity and thermal efficiency on the baseline case. Numerical simulations the seven thermal power plants are evaluated as follows: A. Modified Rankine cycle (73 MWe) with superheating and regeneration, one conventional boiler burning fuel oil and one old steam turbine. B. Fully-fired combined cycle (240 MWe) with two gas turbines burning natural gas, one recuperative boiler and one old steam turbine. C. Fully-fired combined cycle (235 MWe) with one gas turbine burning natural gas, one recuperative boiler and one old steam turbine. D. Fully-fired combined cycle (242 MWe) with one gas turbine burning natural gas, one recuperative boiler and one old steam turbine. The gas turbine has water injection in the combustion chamber. E. Fully-fired combined cycle (242 MWe) with one gas turbine burning natural gas, one recuperative boiler with supplementary burners and one old steam turbine. The gas turbine has steam injection in the combustion chamber. F. Hybrid combined cycle (235 MWe) with one gas turbine burning natural gas, one recuperative boiler with supplementary burners, one old steam boiler burning natural gas and one old steam turbine. G. Hybrid combined cycle (235 MWe) with one gas turbine burning diesel fuel, one recuperative boiler with