15 WHERE ARE
ENERGY TECHNOLOGY PATHS
TAKING US?

• Neilton Fidelis da Silva is a professor at the Rio Grande do Norte Federal Education, Science and Technology Institute (Ifern). He has undergraduate degrees in electrical engineering from the Federal University of Rio Grande do Norte (UFRN) and electricity from the Federal Technological University of Paraná (UTFPR), an MA in electrical engineering from UFRN and a PhD in energy planning from the Federal University of Rio de Janeiro (UFRJ). He is currently an advisor to the Executive Secretariat of the Brazilian Climate Change Forum and a researcher at the International Virtual Global Change Institute (IVIG/Coppe-UFRJ).
  Luiz Pinguelli Rosa is a professor with the Energy Planning Program at the Federal University of Rio de Janeiro (UFRJ), where he directs the Alberto Luiz Coimbra Engineering Postgraduate Study and Research Institute (Coppe), and he is the executive secretary of the Brazilian Climate Change Forum. He has an undergraduate degree in physics from UFRJ, an MA in nuclear engineering from Coppe/UFRJ and a PhD in physics from the Catholic University of Rio de Janeiro (PUC-Rio). In the past he has served as the chairman of Eletrobras, a member of the Pugwash Council and a member of the Intergovernmental Panel on Climate Change (IPCC).
  Marcio Giannini Pereira is a researcher at the Eletrobras Electricity Research Center (Cepel), a consultant and speaker in the area of sustainability and energy, a member of the editorial council of Revista Brasileira de Tecnologia e Negócios em Petróleo (TN Petróleo), and a research fellow at the University of California, Berkeley’s Renewable & Appropriate Energy Laboratory (RAEL). He has an undergraduate degree in economics from the Federal University of Rio de Janeiro (UFRJ) Economics Institute and an MA and PhD in energy planning from Coppe/UFRJ. He has authored many articles published in specialist periodicals and papers for national and international events. He produces the “Energia, Sociedade e Mudanças Climáticas” (“Energy, Society and Climate Change”) blog.

Imagine the world with its current population of 7.3 billion people, but without the diversity of energy sources we now have. If we still lived in the era of work done only using our own muscles and heat produced from burning biomass, there would certainly not be enough food and firewood for so many people; our life expectancy would be much shorter (the population would probably not be as large as it now is); and we would be very far from enjoying the comfort and productivity that technology offers us.

The whole human development process has a close relationship with the evolution of our mastery and use of energy sources available in nature, and our relationship with these sources is strongly connected to our structures for the production and consumption of goods and services. Developed over time, our different technologies for converting energy have conditioned various forms of use, with different yields, which in turn have created multiple impacts in socioeconomic and environmental spheres.

We ought to ask ourselves how we will proceed from now on. What paths will we choose? What will our technological options be? Driven by what type of energy? Although some of the world’s population is investing in more efficient conversion technologies (that expand the use of energy with lower consumption of natural resources and lesser environment impacts), the use of techniques dating back to before the steam engine is still significant on the planet. Thus, despite the technological advances recently achieved, and that are still to come, in many regions the energy future remains linked to yesterday’s choices.

To understand this history, from the start we need to remember that, at any time or place, the most complex energy conversion system that humans use resides in our own body. Through digestion, we process converted chemical energy, present in food, into heat and power in our muscles and brain. When transferring necessary work production beyond its body, the human being has two basic ways of converting energy: organic (the use of animal labor to produce mechanical energy, firewood, etc.) and inorganic (waterwheels, windmills, electric machines and internal combustion engines, among other things).

The human being has evolved by exchanging organic converters for inorganic ones. Human and animal traction in the production of goods gave way to mechanized industry, driven firstly by steam and then electricity.

In our homes, the use of natural biomass to cook and generate heat has been progressively replaced by stoves, heaters and other domestic appliances, the result of technical and scientific advances that have enabled the use of previously inaccessible energy sources. We have enormously expanded our use of coal, natural gas, petroleum, electricity and nuclear power. Accordingly, each energy source has filled its own distinctive niche, expanding the use and harnessing of energy resources.

In this process, we see that the evolution of humanity took place through mechanization and the replacement of the rural labor force, whose effect was the migration of a large share of agricultural workers to the services sector and the expansion not only of trade, but also cultural goods. These changes have generated enormous benefits for the population, including the reduction and replacement of tiring work, improvements to health and education, and greater security, longevity and income. Furthermore, with the increase in the controlled energy rate, advances have spread beyond the domestic, agricultural and industrial areas, reaching shipping, railroads, and individual and public transport, benefiting new sectors of production based on mechanical and thermal energy.

As can be seen in the following timeline, energy consumption started to increase at an accelerated rate at the end of the 19th century, and grew even more intensely as of the second half of the 20th century.

• CHANGE IN GLOBAL ENERGY CONSUMPTION OVER TIME [1]

• 1700 WORLD CONSUMPTION PREDOMINANTLY RENEWABLE (FIREWOOD AND BYPRODUCTS)

• 1800 CONSUMPTION GREW 25% DURING THIS CENTURY

• 1850 IN HALF A CENTURY (1800-1850), WORLD CONSUMPTION GREW 47%

• 1900 BETWEEN 1850 AND 1900, WORLD CONSUMPTION NEARLY DOUBLED. AS FIREWOOD USE DECLINED, COAL BECAME THE LARGEST COMMERCIAL SOURCE. OIL, NATURAL GAS AND ELECTRICITY JOINED THE GROUP OF COMMERCIAL SOURCES (ALTHOUGH TOGETHER THEY ACCOUNTED FOR JUST 2%).

• 1950 FROM 1900 TO 1950, GLOBAL ENERGY CONSUMPTION GREW ALMOST TWO AND A HALF TIMES. OIL 24% | NATURAL GAS 8%

• 1970 BETWEEN 1950 AND 1970, WORLD CONSUMPTION OF OIL, GAS AND ELECTRICITY PRACTICALLY TRIPLED. THE OIL CRISIS SPURRED RESEARCH INTO NEW ENERGY SOURCES.

• 1990 FROM 1970 TO 1990, GROWTH IN CONSUMPTION WAS RESTRICTED TO SLIGHTLY UNDER 35%. ACCIDENTS AT NUCLEAR POWER PLANTS. DEMAND AND SUPPLY ACTIONS DUE TO OIL CRISIS.

• 2000 AS THE CENTURY ENDED, FOSSIL FUELS MADE UP 80% OF TOTAL ENERGY CONSUMPTION. CONFLICTS (SCARCITY AND RESTRICTIONS TO ACCESS SOURCES).

In a first evolutionary phase, coal became the main fuel for steam engines, rapidly expanding its frontier of use to a wide range of industries. It soon became the energy symbol of the Industrial Revolution. From then on, the generalized mass use of fossil fuels by humanity constituted a new milestone in the harnessing of natural energy accumulation and concentration processes.

As we know, fossil fuels originate in solar energy accumulated in plants and/or animals subjected to a series of concentration and compaction processes lasting millions of years. There is therefore no possibility for replenishment on the economic timescale demanded by society. Thus, when the use of coal expanded and led to the use of petroleum and natural gas, humanity entered the era of consumption of natural non-renewable energy stocks.

In the initial stage of this era, petroleum was only used in lighting and heat generation, through the use of kerosene. Many changes took place as new technologies were mastered, oil came to be used to directly generate mechanical energy, and it very rapidly became the main energy source for transport.

When it came to gas natural, the evolution was slower. At first it was considered an obstacle to oil production. Discoveries of huge reserves and, above all, the continuous growth of energy needs and the multiplication of energy uses, were decisive for the natural gas industry’s development. Once the barriers imposed by transport costs had been overcome, natural gas became a major fuel.

A second evolutionary phase may be presented in line with the development of a series of technologies that arose in the late 19th and early 20th centuries, which facilitated the spread of electricity use. At the same time, the invention of the alternating current electric generator and electric induction transformers permitted the harnessing of hydraulic energy to be once more included in planning of energy market expansion. Power transmission networks also played an important role in this revival, by enabling the long-distance transportation of hydraulic energy available in reservoirs.

All these discoveries permitted the simultaneous use of multiple energy sources (firewood, coal, oil and hydraulic) in a very flexible way, with higher yields and better quality. This diversity of available energy sources, combined with the accumulation of new technologies, consequently allowed the development of the complex energy system we have today.

Alongside this, mastery of the controlled nuclear fission process made possible the technological transformation of matter into energy. As a result, it seemed that a third phase of energy use had started, given that, as well as having lower costs, this energy source was considered to be unlimited. However, although nuclear energy now accounts for 9.7% of the supply of primary energy on the planet, through installed and functioning systems, there is recurring debate about its viability, as it has been shown to suffer from financial and environmental problems, most notably risks that threaten the population’s safety.

Although nuclear energy now accounts for 9.7% of the supply of primary energy on the planet, through installed and functioning systems, there is recurring debate about its viability, as it has been shown to suffer from financial and environmental problems, most notably risks that threaten the population’s safety.

Another important and more recent development is the large-scale exploration of shale gas – natural gas found inside a type of porous rock known as shale. To remove the gas from this rock, the hydraulic fracturing (or “fracking”) process is used, which involves injecting water, sand and chemical products. There is great potential for contaminating the population’s water supplies, and some people associate this process with the occurrence of earth tremors. Despite the risks, shale gas production has increased rapidly since the year 2000, especially in the United States, where it is expected to make up 50% of total American natural gas in the mid-2030s.

The current global context is therefore marked by extreme dependence on the production and use of fossil energy and ventures linked to the energy chain that impose high impacts on the natural environment, feeding growing distrust among consumers regarding the use of non-renewable energy sources. This has led industrial society to rediscover energy flows based on renewable natural resources and seek processes more in harmony with human life and ecosystems’ carrying capacity. Such flows, associated with new developments in the realms of technology and the organization of production, may enable an increase in energy supply while lessening global dependence on fossil and nuclear fuels.

Among new renewable technologies, technological advances at an international level have been obtained in thermal solar energy, photovoltaic solar energy, bioenergy, wind power and use of solid waste to generate electricity.

Industrial society is led to rediscover energy flows based on renewable natural resources and seek processes more in harmony with human life and ecosystems’ carrying capacity.

The development of alternative energy production techniques based on renewable resources will make it possible to establish multiple, flexible energy systems, which use the diversity of available energy sources and technologies in an integral, coordinated and decentralized manner, and without neglecting energy efficiency actions. Accordingly, if used within certain parameters, new energy production may help to minimize the environmental impacts arising from the functioning of the global energy market, aligning itself with the demands of a society concerned about sustainability.

Finally, one should pay special attention to recent debate about the recording and forecasting of increases in the planet’s average temperature arising from rising concentrations of greenhouse gases, whose main source is the use of fossil fuels. Many scientists tend to agree with the evidence for close links between energy production and usage and so-called global warming. [2]

Among other strategies, renewable energy sources offer the planet the opportunity to reduce carbon emissions and resume the trajectory of inclusive economic development, aligned with environmental balance, which used to be part of humanity’s civilization process, as it was based on renewable energy generation.

• [1] Jean-Marie Martin, “A economia mundial da energia”, São Paulo: Unesp, 1992.
  [2] The Intergovernmental Panel on Climate Change (IPCC), “Fourth Assessment Report: Synthesis Report”, Cambridge, United Kingdom and New York: Cambridge University Press, 2007.