Solar Energy Perspectives - IEA

Chapter 1: Rationale for harnessing the solar resource
Chapter 1
Rationale for harnessing the solar resource
Solar energy has huge potential and its use is growing fast, yet in many quarters it is still
viewed with concern about costs and doubts over efficacy. All countries and economies
stand to gain by understanding solar energy’s potential to fill a very large part of total energy
needs economically, in a secure and sustainable manner in the future. It can also help to
reduce the greenhouse gases (GHGs) that threaten irreversible climate change for the planet.
Solar energy has been the fastest-growing energy sector in the last few years, albeit from
a very low basis. It is expected to reach competitiveness on a large scale in less than
ten years – but today most applications require support incentives, the cost of which is
a serious concern for some policy makers. Some see solar energy as a boost for economic
growth, others as a drag in the aftermath of a global financial crisis and in the context of
sovereign debts. Solar energy currently does little to abate GHG emissions, but it will play
an important and ever-growing role in climate-friendly scenarios in the coming decades.
Nevertheless, solar energy still barely shows up in recent energy statistics (Figure 1.1). Even
among renewable sources, direct uses of solar energy are outpaced by biomass, hydropower
and wind – three forms of renewable ultimately powered by the sun growing crops,
evaporating water and creating the pressure differences that cause wind (Figure 1.2).
Figure 1.1 Evolution of world total primary energy supply (Mtoe)
Other*
Biofuels
and waste
Hydro
Nuclear
Natural gas
Oil
Coal/peat
14 000
12 000
10 000
8 000
6 000
4 000
2 000
0
1971 1975 1980 1985 1990 1995 2000 2005 2009
Note: *Other includes geothermal, solar, wind, heat, etc.
Source: IEA, 2011a.
Key point
At present, only a tiny portion of solar energy's potential is used.
In one sense, the low penetration of solar is because economic analyses do not account for
the many benefits sunshine provides to humanity: keeping the earth’s surface temperature on
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© OECD/IEA, 2011