A sustainable energy system is required globally to avoid catastrophic environmental impacts from continued reliance on non-renewable energy sources like fossil fuels. Currently 88% of global energy comes from sources like oil, coal and gas, emitting large amounts of carbon dioxide and other greenhouse gases. This overdependence on fossil fuels is the main driver of climate change through global warming. A transition is needed to an energy system based on renewable sources like hydropower, biomass, solar and wind power in order to minimize global warming and avoid future environmental disasters. This will require quadrupling renewable energy production and reducing oil and coal usage by half and 90% respectively by 2030 with renewable sources making up 70% of global energy.

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SUSTAINABLE ENERGY SYSTEM REQUIRED FOR THE WORLD
Fernando Alcoforado *
Energy is an essential input for the living beings and the economic and social
development. It can be stated that the most basic need of living beings is to search for
energy to keep their bodies functioning. This aspect, meeting the physiological need,
predominated in human history until to discover that he could control forms of energy
which would be useful as fire, which represented a significant milestone in the field of
human beings towards the use of thermal energy can cook their food and warmth. The
domestication of animals led humanity to the mechanical energy to transport,
agriculture, etc. A few millennia, rivers hydropower and wind began to be used.
However, only with the advent of the Industrial Revolution, some three centuries ago, is
that the use and production of energy assumed fundamental connotation in replacement
of men and animals by machines.
Since the domain of fire 750,000 years ago until the advent of the Industrial Revolution
there was no major change in the way humanity to utilize energy. But with the
Industrial Revolution occurred in England in 1786 and the subsequent industrialization,
the need for power increased and new primary sources, with higher energy density,
were introduced. The use of coal as an energy source marked the end of the era of
renewable energy represented by wood and hydraulic and meager wind farms to start on
non-renewable energy era, the era of fossil fuels. The use of electricity and the invention
of electric machines in the nineteenth century, along with the introduction of motor
vehicles, laid the groundwork for the introduction of modern consumer society,
characterized by an energy intensity never before seen in human history.
With the advancement of industrialization, new fuels of greater energy power were
needed, and the petroleum fuel that met these properties. Thus began a new phase in the
use of liquid fuels that endures to this day. More recently, after the Second World War,
nuclear power seemed a promising alternative for the generation of electricity, but
suffered a major setback due to the nuclear accident at Chernobyl in Ukraine in 1986
and Fukushima in Japan recently. There is no doubt that human activity on Earth cause
changes in the environment in which we live. Many of these environmental impacts are
from the generation, handling and use of energy.
The main reason for the existence of environmental impacts from the generation,
handling and use of energy lies in the fact that global consumption of primary energy
from non-renewable sources (oil, coal, natural gas and nuclear) corresponds to
approximately 88% of full, leaving only 12% renewables. This enormous dependence
on non-renewable sources of energy has caused, plus ongoing concern about the
depletion of these sources, the emission of large amounts of carbon dioxide (CO2) in
the atmosphere, which in 2013 was approximately 36.3 billion tons, about 3.9 times the
amount issued in 1960 (9.3 billion tons).
As a result of excessive use of fossil fuels, the concentration of carbon dioxide in the
atmosphere has steadily increased, leading many experts to believe that the increase in
the average temperature of the Earth's biosphere, which has been observed for several
decades, is due to an " greenhouse" caused by this increase in CO2 and other gases in
the atmosphere, now generically called "greenhouse gases". To avoid the catastrophic
future that portends for humanity resulting from global warming, it becomes an
imperative, among other measures, to reduce global carbon emissions by promoting

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changes in the current global energy production based mainly on fossil fuels (coal and
petroleum), by another structured based on renewable energy resources, hydropower,
biomass and sources of solar and wind power to avoid or minimize global warming and
hence the occurrence of catastrophic changes in Earth's climate.
The International Energy Agency (IEA) warned that "the world will go to a
unsustainable energy future" unless governments adopt "urgent measures" to optimize
available resources [See Article AIE: mundo se encaminha para futuro energético
insustentável (IEA: the world is heading for unsustainable energy future) published in
website <http://g1.globo.com/mundo/noticia/2011/11/aie-diz-que-mundo-se-encaminha-
para-futuro-energetico-insustentavel.html>]. To the IEA, by 2035 the world would need
an investment of U.S. $ 38 trillion in energy infrastructure - two-thirds in countries
outside the Organization for Economic Cooperation and Development (OECD) - to
meet the growing demand, 90% to supply the emerging countries like China and India.
To optimize the energy resources available on the planet, we need to implement a
sustainable energy system on a planetary scale. With sustainable energy system, it is
very possible that natural gas pass to be, among the fossil fuels, the predominant energy
resource in the future. Nuclear energy is not an important source of energy in a truly
sustainable energy system. This is due largely to accidents at Three Mile Island in the
United States, Chernobyl in the former Soviet Union and in Japan Fukushima. A
sustainable energy system will only be possible if energy efficiency is also greatly
improved.
Quadruple the global production of renewable energy is also essential to obtain a
sustainable energy system in the future. This will require the use of biomass and
hydropower, especially in countries with great potential, as is the case of Brazil. Require
also that solar, wind and geothermal energy will be part of the "mix" of the energy
world. The technologies are already available to begin this historic transition of energies
that will only occur through fundamental changes in energy policy in most countries.
The first step is to redirect a large number of government policies so that they are
intended to achieve the core objectives of energy efficiency and reducing the use of
fossil fuels. For example: rewarding the acquisition of efficient vehicles, encourage
alternative mass transport high capacity to replace the automobile industries, restructure
and raise energy taxes on fossil fuels.
In a sustainable energy system, the world oil production should be halved and coal 90%,
while renewable sources of energy should grow nearly 4 times. In 2030, renewable
energy should be of the order of 70% of the total energy of the planet. These are the
requirements of a sustainable energy system worldwide. Regardless of the various
solutions that may be adopted to eliminate or mitigate the causes of the greenhouse
effect, the most important is undoubtedly the adoption of measures to help eliminate or
reduce the consumption of fossil fuels in energy production as well as for your more
efficient use in transport, industry, agriculture and cities (residential and commercial),
given the use and production of energy is responsible for 57% of greenhouse gases
emitted by human activity. In this sense, it is essential to implement a sustainable
energy system.
The use of renewable energy will lead to changes of great magnitude across the globe
highlighting, among them the creation of entirely new industries, the development of
new transport systems and modification of agriculture and cities. The big challenge for
today is to continue the development of new technologies that efficiently and

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economically leverage the energy using renewable resources. This is the energy
scenario that can avoid compromising the global environment.
* Fernando Alcoforado , 74, member of the Bahia Academy of Education, engineer and doctor of
Territorial Planning and Regional Development from the University of Barcelona, a university professor
and consultant in strategic planning, business planning, regional planning and planning of energy
systems, is the author of Globalização (Editora Nobel, São Paulo, 1997), De Collor a FHC- O Brasil e a
Nova (Des)ordem Mundial (Editora Nobel, São Paulo, 1998), Um Projeto para o Brasil (Editora Nobel,
São Paulo, 2000), Os condicionantes do desenvolvimento do Estado da Bahia (Tese de doutorado.
Universidade de Barcelona, http://www.tesisenred.net/handle/10803/1944, 2003), Globalização e
Desenvolvimento (Editora Nobel, São Paulo, 2006), Bahia- Desenvolvimento do Século XVI ao Século XX
e Objetivos Estratégicos na Era Contemporânea (EGBA, Salvador, 2008), The Necessary Conditions of
the Economic and Social Development-The Case of the State of Bahia (VDM Verlag Dr. Muller
Aktiengesellschaft & Co. KG, Saarbrücken, Germany, 2010), Aquecimento Global e Catástrofe
Planetária (P&A Gráfica e Editora, Salvador, 2010), Amazônia Sustentável- Para o progresso do Brasil e
combate ao aquecimento global (Viena- Editora e Gráfica, Santa Cruz do Rio Pardo, São Paulo, 2011)
and Os Fatores Condicionantes do Desenvolvimento Econômico e Social (Editora CRV, Curitiba, 2012),
among others.