EDF, an environmentally-friendly company
Water intensity: water consumed / electrical production of fleet (l/kWh)
- Target (2015-2030): <1 l/k average over 5 years
- 2019: 0.87
- 2018: 0.86
- 2017: 0.94
Key non-financial performance indicator (see concordance table with the non-financial performance statement in section 8.5.4). For the scope and methodology of this indicator, see section 3.4 “Indicators and methodology”. This indicator refers to key stake no. 9 “The circular economy and conservation of biodiversity, water, air, soils and rare resources” described in section 3.6.2 “Description of key stakes in the materiality matrix”.
Taking account of the expected variation in generation resources and the different actions taken to optimise water, total Group-wide fresh water withdrawal and consumption should fall in the coming years. The stated aim is to progressively reduce specific water consumption by 2030 from the 2015 level (0.96l/kWh), and not exceed the target of 1l/kWh on average over 5 consecutive years. This threshold, which is much lower than the industry average, particularly in the US(1), serves to put an exceptional climatic year, which will significantly increase or decrease the annual indicator, into perspective. 2015-2019 average water intensity was 0.91l/kWh.
The optimisation of water used in EDF’s generation activities is vital to ensuring management of water resources and to honouring the Group’s commitment to guarantee multi-purpose water resources (drinking water, water for irrigation, tourism, etc.) and the needs of local authorities. The EDF group works in a number of ways to optimise its water usage and to reduce pressure on the environment:
Water consumption reduction and withdrawal limitation measures
In French overseas departments, where EDF is investing in new thermal power stations in order to balance demand and supply, R&D teams have designed dry air cooling systems for engine cooling, which reduce water withdrawal by 700,000 cubic metres per year per power plant. Now, EDF PEI’s power plants are no longer cooled with saltwater. In 2019, the Golfech nuclear power plant began atrial with a local EMS to reduce its water withdrawals from the Garonne river, as well as use of chemicals to produce demineralised water (300,000m3 /year). In Chile, following a long drought that caused the water table to fall by 1m in less than a year, specific measures were taken for the combined cycle power plant in Nueva Renca, enabling halving of process water, which plummeted from 12t/h in2018 to 6t/h in 2019. In Brazil, a plan for a second combined cycle power plant after Norte Fluminense is under consideration, featuring an air- rather than water-based cooling system from the design phase.
Reuse and recycle water
The recycling of process and cooling water is growing throughout the Group, whereappropriate. In China, the Ultra-supercritical power plant of Fuzhou reuses all itsprocess water sequentially and depending on the quality of water (from cooling towatering ash to gardens). In Dalkia’s large biomass combustion facilities, processwastewater is used to cool bottom ash to limit the volume of liquid effluent to betreated. In France, EDF’s thermal power plants in Cordemais and Martigues recoverrainwater or recycle their effluents so as to reduce their consumption of tap waterby half. In the UK, rainwater is recovered and reused on the Hinkley Point Cconstruction site to eliminate site dust. The new R&D centre in Saclay usesrainwater recovery to supply 50% of toilet water of the site.
In some cases, the supply of part of the water from the heated cooling circuit of certain nuclear power plants for different uses (agricultural, industrial, etc.) is authorised within the framework of specific regulatory requirements.
Desalinating water
EDF has several desalination unit trials on its sites: a desalination unit has been in operation since 2016 at Flamanville 3 to produce demineralised water for processes as well as for other existing reactor units. In southern Corsica, EDF has designed the cold water source for a thermal power plant by installing a sea water inlet, which reduces the consumption of fresh water significantly. In Guadeloupe, the TAC power plant in Jarry Sud also has a sea water desalination facility, which has made it possible to stop using tap water and save around 50,000m3 of fresh water per year. Since the end of 2016, Edison has had one CCG plant (Simeri Crichi) in Italy with sea water desalination systems to replace freshwater withdrawals.
A pilot test of a new technology is ongoing on the combined cycle power plant site in Martigues. If it proves a success, this technology could be used to produce process water from seawater on several sites. The principle, called AquaOmnes, consists of extracting sodium chloride salts (NaCl) from seawater using liquid resins. The liquid resin is heat-regenerated. The purpose of the process is to produce desalinated water (for process water) at a low cost, due to the abundant availability of seawater.
3.3.2.2.1.2 Sharing water
2019 was the hottest year ever worldwide and there were also an increase in the number of extreme events. In Laos, the dry season was longer and more intense, causing a reduction in generation at Nam Theun 2 between May and August. The rainy season was late and intense, featuring two typhons in two weeks (late August) that filled the reservoir more quickly than normal: 240hm3 had to be discharged via the overfall. In France, 2019 was an unusual climatic year with more than nine very dry months and two heat waves in one month, which were exceptionally intense but short-lived, followed by record rain over the last two months. Absolute air temperature records and major thermal impacts on water temperatures were seen on some sites. This situation led to severely low water levels on many waterways and rivers from summer to autumn. To cope with these unusual and even exceptional climatic conditions on certain rivers like the Meuse or the Moselle, various levers were therefore activated within EDF to optimise production(2) and meet the expectations of the stakeholders. Special restrictions were introduced at six dams from June to August and water was released multiple times to provide external back-up in 2019, with a record of 725 billion m3 removed from storage to meet water users’ different needs under the terms of hydroelectric concession specifications or water-sharing agreements. Two dams were requisitioned in accordance with prefectural by-laws to provide additional back-up when water levels were low. Overall, EDF met its commitments to stakeholders in terms of low-water replenishment and agricultural support, as well those concerning flow rate restitution and observance of water levels for tourist-related purposes. Only the Serre-Poncon tourist water level could not be maintained in the final fortnight of August.
Despite particularly dry and hot summer conditions, the loss of nuclear generation in France (ratio of lost-to-produced net energy) related to temperatures and/or river flow rates was limited to 0.35% (i.e. 1.4TWh), down by nearly 50% on 2018 (which was also a particularly hot year).
(1) Intensity ranging between 1.43 and 3.54l/kWh, see “Regional water consumption for hydro and thermal electricity generation in the United States” – Applied Energy journal– May 2017.
(2) These are river-side power plants using fresh water; seaside power plants are not concerned by the issues of temperature rise and flow rates.