- Home
- Report n°4: summary
Report n°4: Summary
How Much to Spend for the Protection of Health and Environment: A Framework for the Evaluation of Choices - October 2005
Objectives and methodology
The objective of this research is to design a tool for aiding decision-making and risk management. The tools is based on an evaluation of the costs and benefits of proposed measures to reduce risks in various sectors. This tool is relevant for the activities of the Group Véolia Environnement, including water supply, waste management, energy production, and transport. The tool comprises two parts:
• the ranking of measures in terms of cost-effectiveness (cost per year of saved life);
• recommendations for choosing the actions to implement, consistent with local needs and preferences (in particular the "value of a life year", different in different countries, especially between developing countries and the EU).
The development of the tool is undertaken along two lines. The first consists of quantifying the mortality risks (e.g., years of life lost per kg of particulates emitted by a waste incinerator). The risks are quantified in terms of years of life lost rather than a number of premature deaths, in order to be able to compare risks that involve very different loss of life expectancy per death, such as car accidents and mortality due to the air pollution or smoking. The risks due to pollution are quantified by carrying out an analysis of impact pathways, i.e. the chain emission - immission - dose-response function - monetary valuation, based on the methodology developed by the ExternE (External Costs of Energy) project series of the EC. For each estimate of a risk the confidence interval of the estimate is indicated.
The second line concerns the economic and sociological aspects of different risks. Insofar as data are available, the costs of risk reduction measures in various sectors (e.g., public health, road safety, air pollution regulations) are listed. These costs are compared with the benefit calculated by using "the value of a life year". The evaluation of actual expenditures for the reduction of risks in various sectors will make it possible to reveal any inconsistencies, and it can help determine an appropriate value of a life year.
Results
Some key results of this project are shown in Figures 1-3 and Tables 1 and 2. Figure 1 shows the damage costs for the most important air pollutants, in € per kg of pollutant emitted to air. For primary pollutants that are harmful mainly by inhalation, the cost varies strongly with site of the source and stack height; in this case the values indicated are for typical industrial sources ("urban"), but for the PM the costs are also indicated for sources in Paris and in a rural zone.
Figure 1
A possible format for representing the uncertainty of damage costs. The numbers are for LCA applications in the EU15 [ExternE 2004]. The error bars indicate the 68% confidence interval; on the logarithmic scale they are symmetric around the median (= geometric mean of lognormal distribution). The broad hollow bars and the numbers are the mean which is larger than the median. The gray S-shaped curve indicates the probability that the true cost is above a specified value.
For greenhouse gases the cost is taken as 0,019 €/kgCO2éq
As for variation with site and stack height, the following rules can be recommended for modifying factors:
- no variation for globally dispersing pollutants such as CO2;
- weak variation for As, Pb and dioxins because non-inhalation pathways dominate: ≈0.7 to 1.5;
- weak variation for secondary pollutants: ≈0.5 to 2.0;
- strong variation for primary pollutants: ≈0.5 to 5 for site, ≈0.6 to 3 for stack conditions (up to 15 for ground level emissions in big city).
Using these costs per kg of pollutant, the damage costs ("external costs") of incineration and landfill are evaluated for various scenarios for the recovery of energy and materials. The stages of the life cycle taken into account are transport (from the sorting station to the incinerator or discharge, the waste treatment itself, and the recovery of energy and materials. A summary of the comparison of the external costs of incineration and landfill is shown in Figure 2. It highlights the importance of energy recovery for such a comparison.
For that reason we consider a fairly large number of options (indicated in the figures by labels such as E=c+o, c being coal, o oil, g natural gas and n nuclear):
for incineration:
- recovery of heat and electricity, for typical installations in France, according to ADEME [2000] (E=..., H=...),
- recovery of electricity (E=...),
- recovery of heat (H=...);
for landfill:
- no energy recovery,
- recovery of electricity, by motor (reciprocating engine) (E=...),
- recovery of electricity, by turbine (E=...),
- recovery of heat (H=...).
Figure 2
Results of total damage cost for all options. If electricity displaces nuclear, damage costs are essentially the same as for the case without energy recovery.
Figure 3 presents, for several of the scenarios, the detail of the total external cost. For a landfill, the external cost is dominated by greenhouse gases, especially because not all of the methane can be captured. On the other hand, the recovery of energy has a strong influence on the result for incineration. In the case of an optimal recovery (e.g. Saint Ouen, just north of Paris) the total impact can be positive (negative external cost). In France recovery in the form of electricity brings only one very small benefit in terms of external cost, by contrast to other European countries, since the electricity produced by an incinerator supplies the base load, thus displacing nuclear power.
Figure 3
Some detailed results, by stage and pollutant. "Other" = dioxins and toxic metals.
Table 1 : Damage cost of Pb in drinking water at several concentration levels. The cost of an IQ point is taken as 3000 €.
Table 2 : Damage cost of As in drinking water at several concentration levels. The cost of a cancer is taken as 2 M€.
