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Renewable energy sources: at what price? |
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At present, oil and gas are still relatively cheap, despite the fact that prices climbed to record highs in mid-2007. This situation is the principal obstacle to the development of renewable energy options, which are more expensive. In the future, the price of fossil sources should continue to increase. At the same time, renewable options should become cheaper, principally due to technical progress and the growth of long-run production of equipment.
In the meantime, renewable energy is dependent on government aid if it is to progress. It is no secret : renewable energy options develop the most rapidly where they are best-supported; in Germany, for example, where their use is encouraged by a particularly advantageous legal framework.
The limits to renewable energy sources are the limits on the surface areas that can be devoted to their production :
Grants and direct aid;
Purchase of the electricity produced at preferential tariffs, higher than normal tariffs (this is the solution imposed by the French government on the EDF, the French electricity distributor);
Tax breaks for individuals who install systems of renewable energy production in their homes.
The limits of renewable energy are physical limits: the maximum area of cultivation that one can devote to the biomass for energy purposes, the number of wind turbines that can be installed on a site where the wind blows frequently, the surface area that can be devoted to the panels of a solar heating installation…
In the medium-term future, even if many of them have significant development potential, the renewable sources will not be able to supply the volumes of energy that the planet consumes by using fossil energy. The WETO 2003 report (World Energy, Technology and Climate Policy Outlook) of the European Commission even forecasts that the share of renewable energy in world energy consumption is going to decrease progressively, from 13% to 8% between 2000 and 2030, despite the expected development of these new energy sources. This is because our consumption of energy will increase faster than the production of energy from renewable sources.
This certainly does not mean that renewable energies have an insignificant role to play. Continued development and further research into even more efficient technologies must be pursued. Because in the longer term, it is those energy sources that will certainly take over from fossil sources when the latter approach exhaustion. However, these developments will go on alongside very significant energy savings, resulting in major changes in our lifestyle, movement and work.
The countries which have chosen this direction:
All renewable sources taken together hardly represent 2.5% of world energy consumption (excluding wood for heating, which accounts for about 10% of the total). The majority of the 'renewables' are used to produce electricity, as is the case, for example, with the principal source of renewable energy exploited at present: hydroelectricity (2.15% of total world energy production). |
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Electricity production from hydroelectric sources (billions of kWh).
Source : Energy Information Administration / Department Of Energy |
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The example of hydroelectric energy.
World hydroelectric generation by country (2005)
| Country |
Hydroelectric Generation (billions of kWh) |
| China |
397 |
| Canada |
360 |
| Brazil |
334 |
| United states |
270 |
| Russia |
173 |
| Norway |
134 |
| India |
99 |
| Japan |
77 |
| Venezuela |
74 |
| Sweden |
72 |
| France |
51 |
| Paraguay |
51 |
| Turkey |
46 |
| Italy |
41 |
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Electricity production from geothermal, solar, wind, wood and biomass sources (billions of kWh).
Source : Energy Information Administration / Department Of Energy |
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The hydroelectricity-producing countries are also the consumers, even if some, like France, export a little electricity to neighbouring coutries (thanks to the contribution of nuclear energy). Hydroelectric energy appears to be more evenly spread across continents than fossil energy sources.
The principal countries producing electricity from other renewable energy sources are the following:
2005 levels of production of electricity from renewable energy sources: geothermal + solar + wind + wood + energy from waste (incineration and methane production)
| Country |
Electricity Generation from renewable energy sources excluding hydroelectricity (billions of kWh) |
| United States |
99.7 |
| Germany |
42.9 |
| Japan |
23.3 |
| Spain |
23.2 |
| Brazil |
18.3 |
| United Kingdom |
15 |
Italy
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14.2 |
| Canada |
10.1 |
| Danemark |
10.1 |
| Mexico |
9.5 |
| Finland |
9.4 |
| Philippines |
9.4 |
| Sweden |
8.8 |
| Netherlands |
8.6 |
| India |
7.7 |
| France |
6.3 |
| Indonesia |
6.3 |
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It is largely the developed countries that are involved, even if Brazil (biomass), the Philippines (geothermal energy) and India (wind energy) stand out as pioneers of renewable energy among developing countries. Worthy of note is the tiny contribution from renewable energy in Russia and, above all, the situation in Africa where solar energy would nevertheless appear to be a promising energy source.
Research and technical progress for the future
The technological principles of renewable energies are available, but much more can be expected from research into the improvement of efficiency of the techniques, for example:
Improvement in yields of photovoltaic cells: research is ongoing into crystalline forms of silicon or other semi-conductors capable of going beyond the best yields currently attainable (15%);
Improving the yields of plants grown as green fuels and finding ways of using the whole of the plant;
Productivity improvements for plants destined as green fuel;
Continuation of tests of different installations for the capture of energy from waves and maritime currents, in order to select the most efficient methods before generalising their use;
Improvement in procedures for the management of electrical energy, so that electricity resulting from intermittent energy sources, such as the wind and the sun, can be better integrated into the distribution network.
The really positive surprise for mankind could come from the success of long-term research, already begun, aimed at controlling nuclear fusion.
Nuclear fusion could theoretically allow us to achieve the energy dream: inexhaustible supplies in large quantities. But we won’t have an answer before 40 years at best.
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