The recovery objective as provided for in recent laws is not subject to any quantified obligation, just as it does not establish any hierarchy between on the one hand the material recovery, which consists in the production of new raw materials from the recycling of materials or the composting of organic materials, and on the other hand energy recovery, that is to say the production of electricity or district heating from thermal processes including more common is incineration.

Faced with the increase in incineration capacities, quantified recovery targets will be introduced (targets quantified by type of material (packaging), etc.) and attempts to establish a hierarchy between the recovery methods. The recovery effort that became widespread in the 1990s focused mainly on packaging. For several years now, there has been a trend towards recovery based on an approach of end-of-life products (tires, end-of-life vehicles, waste electrical and electronic equipment). This development which stems in particular from European regulations, gives rise to the production of specific regulations by sector, in a logic of producer responsibility.

In addition to the constraints of a regulatory nature, the lever of financial aid is used to impose valuation objectives, or even to establish a hierarchy between the valuation methods. Incineration is only subsidized on condition that it includes energy recovery. Then from 1996 the incineration aid paid to communities was based on the results obtained in terms of recycling and composting.

Thus there is a differentiation between the recovery methods: energy recovery must be preceded by one or more forms of material recovery. It was in 1998 that an ambitious 50% material recovery target was set, thereby establishing a hierarchy between material recovery and energy recovery. That said, this new objective, set at the national level, gave rise to confusion as to its translation into departmental plans.

Despite these inflections the insufficiency of aid intended for the financing of separate collections and composting, coupled with a lack of legal incentive in recovery, will not allow a commitment of the communities towards advanced recovery systems, to the benefit of a shift towards incineration and energy recovery, which appear to be easy solutions combining high technical reliability and social acceptability assumed to be greater than landfilling. Incineration plant projects carried out by local authorities, supplying district heating networks and or the electricity distribution network, become energy recovery units.

The issues of valuation and prioritization will be renewed at the turn of the year 2000 with the rise of concerns about climate change. The waste sector, mainly producing methane and CO2, estimated to be responsible for 3% of global greenhouse gas emissions is invited to take part in the national effort to reduce emissions.

The climatic challenge thus updates the link between waste management and energy production born with the oil shock of the 1970s. Taking into account the atmospheric and energy impacts of waste takes on a double meaning: the waste sector, called upon to helping to reduce atmospheric emissions (especially methane through the recovery of biogas from landfills), also appears to be an alternative energy supplier sometimes qualified as renewable.

With the fight against climate change, the recovery and recovery of energy from waste treatment (incineration with production of heat and electricity, anaerobic digestion, landfill biogas) see their interest increase. The waste is indeed part of the biomass and therefore participates in the production of renewable energy.

The abandonment of the idea of ​​hierarchy between types of recovery then prevails within the institutional and professional spheres, reinforced by the development of methods for assessing environmental pressure which promote a global understanding of impacts such as the analysis of life cycles.

The concern for a global environmental assessment integrating the question of atmospheric impacts is included in the regulations relating to waste management planning: from 2005, departmental and regional plans for the elimination of household and industrial waste are subject to an environmental report.

This redesign of the impact assessment, marked by the attention paid to greenhouse gas emissions, however comes up against difficulties in circumscribing the scope of the measure: should we, for example, take transport into account? impact assessment of waste management systems?