Feature Report: Solar, an Energy of the Future

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Solar in the Global Energy Mix


Solar, in all its forms, accounts for less than 1% of today’s global energy mix. However, its exponential growth should ensure it plays a vital role in the future energy mix.

The rooftop solar array on the Colorado Convention Center in Denver, in the United States. © SUNPOWER CORP

Right now, the share of solar (photovoltaic and solar thermal) in final energy consumption is tiny. Solar heatIn the field of statistical thermodynamics today, heat refers to the transfer of the thermal agitation of the particles making up matter... and powerIn physics, power is the amount of energy supplied by a system per unit time. In simpler terms, power can be viewed as energy output... provide just 87 million of the more than 12 billion tons of oil equivalentUnit of energy measurement corresponding to the energy produced by the combustion of a ton of oil... (toe) consumed worldwide, making up 0.7% of the global energy mixThe range of energy sources of a region.. Fossil fuels dominate, representing 78% of the energy mix. Looking at electricityForm of energy resulting from the movement of charged particles (electrons) through a conductor... alone, photovoltaic solar accounts for a mere 0.5% of the world’s electricity output.1

Low-temperature solar thermal energy for local use accounts for 70% of solar energy

Nevertheless, the extremely rapid growth of installed solar capacity has convinced most analysts that this share will increase spectacularly in the future. From 2020, photovoltaic energyEnergy produced by the photovoltaic effect. could cover 2.2% of power generation worldwide, and could increase to 30% in the second half of the century.

Geographical Distribution of Different Types of Solar Energy

There are different types of solar energy, and they are not all developing in the same way.2 (See close-up: "The Two Types of Solar Energy, Photovoltaic and Thermal").

Low-temperature solar thermal energy, which directly uses the Sun’s heat in small, stand-alone installations, represents the biggest share of solar energy at over 70%. Installed capacityThe power generation capacity of a particular plant. It is usually expressed in megawatts (or sometimes even gigawatts)... doubled in the five years between 2007 and 2012, to 233 gigawatt-hours (GWh). China, which has invested heavily in solar collectors, is the biggest user of this source of heat, with close to two thirds of global capacity, followed by the United States and Germany.

0.7% solar’s share of global final energy consumption

The use of solar energy to generate electricity is growing at an even faster pace.

Installed photovoltaic capacity, which now accounts for more than 30% of total solar energy, was multiplied by 10 in the period 2007-2012. At the end of 2013, installed capacity stood at 134 GWh. Germany still leads the sector, but China is now experiencing faster growth.

Concentrated solar power — large thermodynamic solar power plants that produce electricity from heat — only accounts for 0.7% of solar energy, but it is expanding fast. Installed capacity was multiplied by six between 2007 and 2012 and stood at 3.1 GWh at the end of 2013. There are 70 plants in nine countries worldwide, with two flagship countries: Spain (48 plants) and the United States (13 plants). Others are under construction or in the pipelinePipeline used to transport gas over a long distance, either on land or on the seabed., particularly in India and China.


Sources :

(1) Renewable Energy (french only)

(2) CNRS review (french only)

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