We previously discussed the global energy context dominated by fossil fuels.
Let us focus now to the environmental,
on climate change context.
This issue was the subject of the recent global conference
held in Paris in late 2015, COP 21.
The following curve, which comes from the IPCC,
illustrates a continuous increase of emission of greenhouse gases, GHG.
The annual growth rate exceed two percent since the beginning of the 21st century.
Energy represent 69% of the issue followed by agriculture,
11%, on industrial processes, six percent.
The carbon dioxide produced by fossil fuels, oil, gas,
and coal, represent almost the two-third of the overall emission.
Thus, it can be inferred that massive use of fossil fuels
leads to a major environmental problems whatever the level of resources.
This CO2 is distributed very unevenly in the world.
The gross of this issue is in part due to
the recent development of major Asian economies,
China and India as seen in this figure.
China became the largest emitter of CO2 in the world since about 25.
However, per capita, Americans are by
far the biggest emitters as shown in the second figure.
As you know, global warming is attributed
to the growth of the emission of greenhouse gases.
One of the key elements to consider is the stability of CO2.
Once emitted into the atmosphere,
CO2 can stay there for a very long time even a century.
We must therefore take into account the cumulative quantities.
The extrapolation of current trends GHG increase
above two percent per year will lead to an environmental disaster.
Temperature increase greater than three degrees in 2100.
Red curve, the scenario is much more proactive corresponding to
an increase of less than two degrees in both a sharp degree of GHG.
Bottom curve, this requires a break in
the power generation modes with a sharp decrease in the consumption of fossil fuels.
What alternative sources are available?
Global demand for electricity,
heat on total energy are indicated on the red-dotted lines.
Estimated of renewable resources correspond to the blue rectangles.
They are clearly variable note as compared to the demand.
In particular, geothermal and wind power can cover
the world electricity demand regardless of economic criteria.
But it is clear that the solar resource is by far the most abundant.
It is several orders of magnitude higher than
the global demand for energy and other renewable resources.
It of course remains to estimate the cost of energy.
This figure represent a realistic energy scenario in the medium term.
The current energy panorama is dominated by fossil sources.
It will always be the case in 2035 where they still
represent 74% of global production, gas overtaking coal.
The share of nuclear power should remain constant,
about six percent of the total.
Renewable energy, wind, solar is going strongly,
although the contribution remains rather weak,
six percent in 2035.
In the longer term,
2050, end of the century,
the share of fossil fuels should decline to
limit global warming as foreseen in the German scenario.
The share of solar energy should become
dominant in the second-half of the 21st century, yellow curve.
In summary, renewables appears very
promising in the energy on climate context of the 21st century,
especially solar energy which is by far the most abundant.
The use of this energy is booming.
We will discuss later the different uses of solar energy. Thank you.