Renewable and non-renewable

Some sources are renewable, i.e. they provide energy, which is constantly regenerated by means of chemical transformations (e.g. biomass) or physical transformations (e.g. water power, solar, wind power, etc.). In particular the sun, the wind, the water cycle, the tides, the heat of the Earth are non-exhaustible sources, which are always available and will never end. Biomass, instead, can re-generate within times that are similar to man’s life. With reference to wood, for example, it is always possible to have some combustible available, even though sometimes it is necessary to consume a small quantity of it and reforest in those areas where trees have been cut down.
Non-renewable sources, instead, are characterised by long regeneration times, so long (millions of years) that after they have been exploited they are considered depleted. They are those energy sources that took millions of years to form, like fossil fuels (oil, coal, natural gas) or when our planet was formed, such as uranium. These sources, although there is still plenty of them, are limited and represent a sort of energy warehouse on the Earth.  In 2013, only 13.5% of the energy consumed in the world derives from renewable sources. All the rest derives from non-renewable sources, mainly from fossil fuels (81.7%) and 4.8% from nuclear plants (International Energy Agency (IEA) – Key World Energy Statistics 2015).

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Facts

  • 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…

  • 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...

    Phyto-depuration

    A very interesting project has been carried out by Lombardy region...

  • 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…