Primary and secondary sources
The numerous existing energy sources can be classified in different ways. Primary sources can be used directly, as they appear in the natural environment: coal, oil, natural gas and wood, nuclear fuels (uranium), the sun, the wind, tides, mountain lakes, the rivers (from which hydroelectric energy can be obtained) and the Earth heat that supplies geothermal energy.
Secondary sources derive from the transformation of primary energy sources: for example petrol, that derives from the treatment of crude oil and electric energy, obtained from the conversion of mechanical energy (hydroelectric plants, Aeolian plants), chemical plants (thermoelectric), or nuclear (nuclear plants). Electric energy is produced by electric plants, i.e. suitable installations that can transform primary energy (non-transformed) into electric energy.
Special reports
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13 May 2013
Small steps, great footprints
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18 January 2016
Ten years of oil demand
Eni has recently published the 14th edition of the 2015 World Oil and Gas Review...
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27 September 2012
Over 7 billion people on Earth
Demographers have estimated that on 31 October 2011 world population...
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18 May 2011
Artificial photosynthesis
The history of science and technology is packed with discoveries and inventions inspired by nature...
10 September 2020
A simple and ingenious invention
There are objects so simple and ordinary that we forget their existence when we don't need them. Their presence is…
17 March 2020
Energy and renewable sources: what is the current status?
The unstoppable growth of renewable sources continues…
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13 May 2013
Small steps, great footprints
Have you ever wondered how much space is taken up by an apple or a steak?...
-
18 January 2016
Ten years of oil demand
Eni has recently published the 14th edition of the 2015 World Oil and Gas Review...
-
27 September 2012
Over 7 billion people on Earth
Demographers have estimated that on 31 October 2011 world population...
-
13 May 2013
Small steps, great footprints
Have you ever wondered how much space is taken up by an apple or a steak?...
-
18 January 2016
Ten years of oil demand
Eni has recently published the 14th edition of the 2015 World Oil and Gas Review...
From the Multimedia section
Facts
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Where does energy come from?
Every day the Earth receives enough solar energy to satisfy the global energy need...
Electricity and electrons
In all electric plants, excluding photovoltaic solar plants, mechanic energy is transformed into electric energy through the same basic procedure...
Peat and peat-bogs
The age of coal starts towards the mid 1600s, stimulated by the need for finding an alternative energy source to…
-
Geographical distribution of energy
Every day the Earth receives enough solar energy to satisfy the global energy need. Unfortunately we cannot exploit all this…
Orimulsion
In order to improve supply security, and therefore the diversification of sources to produce electric energy...
Cracking operations
At the end of the fractional distillation, long hydrocarbon molecules can be transformed into lighter molecules by means of more…
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Hydrogen from biomass
Hydrogen is an energy carrier that allows to generate energy in an environmentally sustainable way...
ITER fusion reactor
The reactor that will be able to produce electronuclear energy without risk of explosion or radioactive waste...
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2 March 2011
Where does energy come from?
Every day the Earth receives enough solar energy to satisfy the global energy need...
Electricity and electrons
In all electric plants, excluding photovoltaic solar plants, mechanic energy is transformed into electric energy through the same basic procedure...
-
Peat and peat-bogs
The age of coal starts towards the mid 1600s, stimulated by the need for finding an alternative energy source to…
Geographical distribution of energy
Every day the Earth receives enough solar energy to satisfy the global energy need. Unfortunately we cannot exploit all this…
-
Orimulsion
In order to improve supply security, and therefore the diversification of sources to produce electric energy...
Cracking operations
At the end of the fractional distillation, long hydrocarbon molecules can be transformed into lighter molecules by means of more…
-
Where does energy come from?
Every day the Earth receives enough solar energy to satisfy the global energy need...
-
Electricity and electrons
In all electric plants, excluding photovoltaic solar plants, mechanic energy is transformed into electric energy through the same basic procedure...
-
Peat and peat-bogs
The age of coal starts towards the mid 1600s, stimulated by the need for finding an alternative energy source to…