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Won't "the technique" save us ?

September 2003

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Periodically various technical solutions are evoked that woulf allow us to "go on living like today" (that is use energy sources that lead to CO2 emissions) without increasing the greenhouse gases emissions, waiting calmly that energy efficiency allows to cut them by two. What can we hope exactely ?

First of all it is important to know that it is not possible to filter the atmosphere to remove the gases we have already emitted. "Technique" hence cannot do much for this, and won't avoid us an ultimate global warming of at least 1 °C.

This being said, we can hope and/or expect a large number of innovations. But today it seems difficult to state that these innovations to come will prevent us from having to change some habits anyway :

First we can put back under the ground the CO2 produced when we burn coal, gas or oil. It is technically feasible, but is limited to massive sources of CO2 (power plants and large factories), what leaves apart 50% of the CO2 emissions and all the emissions of the other greenhouse gases. In addition any factory will probably not be fitted with thess complex installations in a couple of years, at least not with the present priority management.

We can improve the energy efficiency : it means that we can get the same unitary service while burning less fossil fuels. But, as surprising at it may seem, this does not necessarily lead to reductions if a constraint on the global consumption is not set otherwise.

For example, the improvements made for the last 15 years on car engines have been completely nullified by the fact that people now buy heavier cars, with more equipment (air con) that consume energy.

The result of all this is that the average consumption of a new car sold in France has increased - and not a t all decreased - over the last 15 years.

Getting a reduction would have required that everybody avoided from replacing an old "inefficient" subcompact car by a new "efficient" large family car, but replaced the old subcompact by a new subcompact, reducing emissions then ranking higher in the priority list than comfort.

We can change of sources of primary energy. But as these sources are often less convenient to handle than oil ans gas, or more expensive, or require more precautions (like nuclear), or just can't deliver the same power, for example for renewables, it seems likely that we can't reach an "energetically virtuous"" world just with technical innovations.

A more general argument might possibly be called to illustrate the limitations of "technique". Indeed, if efficiency is achieved without a constraint on perpetual growth, it can paradoxically lead to an increase of the global pressure : by offering products or services that each are less "nocive" for the environment, we increase their social acceptability, and we diminish their unit cost (every user will pay less in natural resources or in pollution costs), and this generally leads to an expansion of the use that does more than compensate the unit gains.

For example, if the only available air transport today was that of private jets, most certainly the consumption per passenger would be much higher than today, but this very fact would bar air transportation to most people (who could not afford to pay for such a consumption), and the global consumption of kerosene would probably be much lower. In the same idea, if our engineers never could achieve better than cars doing 50 liters/100 km (that is 5 miles to the gallon), with the same gasoline price (in Europe), it is probable that the overall consumption of oil would be much lower, because nobody could afford driving a car.

In short, without any socially accepted constraint on the global demand, it can be quite well pleaded that an enhanced unit efficiency generates probably an increase of the global consumption and not a diminution.

If there is a consensus on the idea of reducing the fossil energy consumption, the most efficient way to do it, historicaly, is to raise the prices, that is to increase the taxes.

It happens that on the long run the main factor that governs the consumption is not the efficiency of the devices that require energy (houses, cars, planes, fridges...) but basically its price. In other terms, if we really wish to solve the climate change problem, it is not the path of increasing the energy efficiency which is to be explored first, but the fiscal approach. Refusing the possibility of growing taxes (a growth that can be progressive, of course) on the greenhouse gases emissions (and thus on anything that comes from oil, gas or coal) is quite alike refusing to act voluntarily against the process.


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