In the space of 10 years, EDF has brought down its atmospheric emissions per kilowatt-watt generated by 60%. This reduction was achieved by combining several technologies.
Improving the quality of fuels used
To reduce atmospheric emissions from the fossil-fired generation fleet, the first step was to use better-quality fuels, such as coal with lower ash content and fuel oil with low sulphur content. The fuel oil-fired Porcheville and Cordemais power plants, for example, now use fuel of very low sulphur content (less than 0.55% sulphur).
Equipping coal-fired plants with scrubbers
Several technologies have been introduced at the Le Havre and Cordemais plants:
• Flue gas desulphurisation, or “scrubbing”, reduces sulphur dioxide emissions by 90%. The process consists in channelling the flue gas through water saturated with lime before it reaches the stack
• Denitrification eliminates 80% of nitrogen oxide emissions. Used for the first time on this scale in France, denitrification anticipated application of the European Directives by nearly 10 years. “Low NOx” burners installed on two fuel oil-fired plants in 2011 and 2012 reduced these emissions 50–70%
• Dust collectors remove virtually all (99%) of the flyash generated by coal combustion
Innovative technologies for the environment
The combined cycle gas turbine power plants currently being developed have excellent energy efficiency – up to 62% at the Bouchain power plant under construction – and emit only half the amount of CO2 discharged by conventional coal-fired plants.
High-efficiency coal-fired plants (45%) and very-high-efficiency coal-fired plants (50%) achieve optimum environmental performance.
Lastly, the Group is continuing its research on carbon capture. For more than two decades, EDF has been measuring its CO2 emissions. Since 2005, the results have been audited by accredited independent bodies. By 2016, EDF had reduced the volume of its CO2 emissions by 50% from their 1990 level.