Dividing CO2 emissions due to energy by four: the Negatep scenario

The Negatep scenario aims, in accordance with the 2005 energy orientation Act, to cut CO2 emissions by four. In addition to energy savings without which the '4 factor' would be unattainable, fossil fuel has to be replaced, as far as possible, by energy sources that do not send out carbon dioxide, both in direct heat or via the electricity vector. The 2007 version of the scenario was based on pre-2006 data. Since then, many studies have been published and several new elements have emerged, including the Grenelle de l'environnement, the European 'energy climate' directive referred to as '3 x 20' and the specific commitment by France to produce 23 % of its energy from renewable energy as from 2020. One can only acknowledge that not all the options resulting from the 'Grenelle' to reach the various objectives are optimised, failing having defined and applied economic criteria allowing to look for the best cost/ benefit compromise. A reassessment of Negatep was needed: that is the purpose of Negatep 2010, which confirms the major directions of Negatep 2007. In order to reach the 4 actor goal, the study shows that the following is needed: - almost eliminate oil and gas in the home and tertiary sector. Means exist, combining better insulation, renewable heat energies whether combined or not with heat pumps, and smartly used direct electricity. The main issue is financing, whose difficulties should lead to always look for the least costly approaches; - reduce the use of oil in transport. That is a dual revolution: rethinking mobility (public transportation, freight) and replacing oil with electricity either directly in hybrid or electrical chargeable vehicles or by providing all or part of the energy needed for biofuel synthesis; - seriously reduce fossil fuel in industry. This involves process changes (therefore massive investments); - increase strongly the share of electricity in the energy mix, maintain the sharp of nuclear energy in electricity production and as long as cost efficient storage means have not been developed, reduce the share of intermittent electricity to the level that the electrical network can bear without increasing the capacity of gas plants. (authors)